Resolution 025-2017RESOLUTION NO. 025 -2017
A RESOLUTION OF THE BOARD OF COUNTY COMMISSIONERS
OF MONROE COUNTY, FLORIDA. ADOPTING THE FINAL REPORT
OF THE TIDAL FLOODING ROADS DEMONSTRATION PROJECTS
WHICH RECOMMENDS ROAD IMPROVEMENT PROJECTS IN TWO
COMMUNITIES AND TO MOVE FORWARD WITH THE DESIGN
PHASE TO IMPLEMENT THE RECOMMENDATIONS; PROVIDING
FOR AN EFFECTIVE DATE.
WHEREAS, Monroe County roads have been impacted by tidal flooding in 2015 and 2016 from King
Tides; and
WHEREAS, knowing that Monroe County would be impacted by increased annual flooding from King
Tides, storm events and /or sea level rise countywide, the County decided to move forward with a "Pilot
Roads Project" to test methods for determining future flood risk scenarios and set a policy framework for
making road elevation decisions relative to future road improvement projects; and
WHEREAS, the Board of County Commissioners accepted the GreenKeys Sustainability Action Plan in
2016 which included Recommendation 1 -19 for a "Pilot project to conduct a Comprehensive Feasibility
Study for Enhanced Stormwater and Tidewater Criteria (prioritizing areas) for near -term areas subject to
inundation risk, including nuisance flooding (in two locations) "; and
WHEREAS, specific roadway areas were chosen within two communities for the study where impacts
from the 2015 King Tides were the highest, including the Twin Lakes Community in Key Largo (Shaw
Drive, Crane Street and Adams Drive) and the Sands Community in Big Pine Key (Father Tony Way and
the Avenues); and
WHEREAS, the Final Report for the Monroe County Pilot Roads Project: The Sands and Twin Lakes
Communities includes a Methodology and Technical Background (Part 1), Recommendations and Legal
and Policy Analysis (Part 2), Appendix 1: A Draft Ordinance, and Appendix 2: "Methodology for
development of flood level estimates for the two communities "; and
WHEREAS, different approaches to conceptual designs for the roads in the Twin Lakes and Sands
Communities were evaluated, including stormwater features, and the Final Report makes specific design
recommendations for incorporating sea level rise projections and an annual level of acceptable flooding
not to be exceeded; and
WHEREAS, the Final Report for the Monroe County Pilot Roads Project: The Sands and Twin Lakes
Communities includes Section 4.5 which is a Final Technical Recommendation using a methodology not
to exceed an annual level of acceptable flooding more than 7 days and to include sea level rise projections
(IPCC AR5 Median from the Southeast Regional Climate Compact's Unified Sea Level Rise Projection,
2015) to provide relief from periodic flooding; and
WHEREAS, the Pilot Project has provided valuable technical, design and policy information, including
specific recommendations for each of the two Communities.
THE REMAINDER OF THIS PAGE PURPOSELY LEFT BLANK.
THEREFORE BE IT RESOLVED by the Board of County Commissioners of Monroe County that:
1. The above recitals are hereby incorporated into this resolution as restated herein constitute the
legislative findings and intent of the Board of County Commissioners of Monroe County, Florida.
2. The Board of County Commissioners shall approve the Final Report for the Monroe County Pilot
Roads Project: The Sands and Twin Lakes Communities.
3. The Board of County Commissioners hereby directs staff to budget funds in the FYI 7/18 budget
and to move forward with the design phase to implement the Recommendations included under
Section 4.5 of the Final Report for the Monroe County Pilot Roads Project: The Sands and Twin
Lakes Communities.
4. This resolution shall take effect immediately upon adoption.
PASSED AND ADOPTED by the Board of County Commissioners of Monroe County Florida,
at a regular meeting of said Board held on the 18'' day of January, 2017.
Mayor George Neugent
Yes
Mayor Pro Tem David Rice
Yes
Commissioner Heather Carruthers
Yes
Commissioner Danny L. Kolhage
Yes
Commissioner Sylvia Murphy
Yes
MADOK, CLERK BOARD OF COUNTY COMMISSIONERS
OF MONROE COUNTY, FLORIDA
B �vv.►
Deputy Clerk
,�..
By. 14407;r,
Mayor
APP,6,OVLi
ASS i;�i
.e-- , /
r--3
S2
. I
2
--J
'-
C
a
cn
CD
jam!'\'`F ;,... 't v.,1F, 7' q •y•. , _ -T_ ..- i1i r ..•r^' ..,
it +` t' ,}.i• •s'-•r ..ti4`1yC%L7 '. ` rye, ; .. ..'
.41
.-. .-..-1,• ..:,, ... ... . . 3.. t• ....%,
'MIK'I -• . - — — • — . . .--
MO N R O E COUNTY PILOT
ROADS PRO JECT:
THE SANDS AND TWIN LAKES COMMUNITIES
f" I'''..''''.-} Monroe County, Florida
4
ERIN L. DEADY, P.A.
11�/ id
�. ♦♦ S BRINCKERHOFFONS
�
f: -
Monroe Cou nty Pilot Roads Project Twin lakes and sands Communities
Final Report
Contents
1 Executive Summary ................................................................. ..............................1
2 Introduction ............................................................................ ............................... 4
3 Part I: Methodology and Technical Background ..................... ............................... 8
3.1 Tidal Flooding Assessment .......................................................... ..............................8
3.2 Climate Change and Sea Level Rise . ............... ........ .... .. ...... .................................. 11
3.3 Engineering Design Assessment ................................................. .............................13
4 Recommendations .................................................................. .............................23
4.1 Establishing a Baseline for Decision- Making ...... ................. ............................... 23
4.2 Example Decision - Making ... ................................... .... ........................................ .... .24
4.3 Stormwater Management Design Alternatives and Recommendations ...................27
4.4 Pavement Design and Inundation ............................................. .............................28
4.5 Final Technical Recommendation ............................................... .............................29
5 Part II: Legal and Policy Analysis .......................................... ............................... 32
5.1 Legal Analysis/ Background ......................................................... .............................32
S.2 Case Studies .............................................................................. .............................38
5.3 Recommendation on Policy ....................................................... .............................42
5.4 Conclusions ............................................................................... .............................46
6 Appendix ................................................................................. .:...........................48
6.1 Appendix 1 - Methodology for Development of Flood Level Estimates for the Two
Communities.......................................................................... .............................48
6.2 Appendix 2 — Draft Ordinance., ............................................................................... so
J a- a r y 7 0 1 7 1 r a g e i
Monroe County Pilot Roads Project Twin I okes and So nds Communities
Final Report
Figures
Figure 1 - Communities Selected for the Pilot Project ....................... ............................... 4
Figure 2 - Study Location - Twin Lakes Community, Key Largo .......... ............................... 5
Figure 3 - Study Location -- Sands Community, Big Pine Key ............. ............................... 5
Figure 4 - Project Technical Work Flow ............................................. ............................... 7
Figure 5 - Vaca Key Tide Gauge Water Level - 1996 to 2016 ............. ............................... 9
Figure 6 - 2015 Tidal Record for Vaca Key Tide Gauge -- Highlighting 2015 Event .......... 10
Figure 7 - Sea Level Rise Projections - Southeast Florida Regional Climate Change
Compact......................................................................... ............................... 12
Figure 8 - Stormwater Pumping Equipment .................................... ............................... 17
Figure 9 - Control Box - Big Pine Key ............................................... ............................... 17
Figure 10 - Current Elevations in the Twin Lakes Community ......... ............................... 18
Figure 11 - Current Elevations in the Sands Community ................. ............................... 19
Figure 12 - Conditions Potentially Impacting Roadway Design (Conceptual) .................. 21.
Figure 13 - Sample Process Evaluation ........................................... ............................... 46
Tables
Table 1 - Analysis of Tidal Water Levels for the Vaca Key Tide Gauge and Estimated
Levels for Two Pilot Communities .................................. ............................... 11
Table 2 - Tidal Condition and Flooding Estimates for Two Communities for Two SLR
Values............................................................................ ............................... 13
Table 3 - Tidal Water Elevations and Recurrence Periods for Big Pine Key ..................... 15
Table 4 - Tidal Water Flevations and Recurrence Periods for Key Largo ......................... 16
Table 5 - Cost Estimates for Reconstructing Roadways in the Two Communities........... 19
I able 6 - Design Scenario Options - Noting Differences .................. ............................... 26
P a g e i i a u z- y i 0- 7
Monroe County Pilot Roods Project Twin Cokes and Sonds Communities
Final Report
1 Executive Summary
This report summarizes the preliminary results of a Pilot Project conducted in Monroe County,
Florida to assess the implications of sea level rise on its roadway improvement program in two
communities. This effort was motivated by two significant events. The first was the release of the
County's GreenKeys! Sustainability Action Plan ( "GreenKeys! Plan ") which made
recommendations to address climate and sustainability issues throughout the County. The
second was the King Tide Event of 2015, which due to a combination of tidal and storm
conditions, caused long -term, disruptive flooding.
The County conducted this pilot study and engineering technical analysis based on a data - driven
method to identify the appropriate design response to potential sea level rise effects on
roadways for two communities. The County's Team developed an approach to define alternatives
for road improvements in the two pilot communities based on several elements:
• Assessed past tidal events in the Keys by analyzing a 20 -year historic tidal record and
determining the statistical probability of tidal flooding for certain events based on that
assessment.
• Used the Intergovernmental Panel on Climate Change ( "IPCC ") AR5 Median and United
States Army Corps of Engineers ( "USACE ") High sea level rise scenarios, used by the
Southeast Florida Regional Climate Change Compact ( "Compact "), to identify potential
rates of increase expected over a 25 year road improvement project lifetime for the road
improvements. These values were then added to those derived from past events to define
flooding recurrence scenarios for the year 2040.
• Developed four design response strategies (6 ", 12 ", 18" and 28" of road elevation) to
evaluate flooding impacts and the benefits gained from those responses.
• Compared design scenarios to tidal flooding recurrence in 2015 and in 2040 to define the
performance of design options under various scenarios.
• Developed design cost estimates for the various identified road elevation scenarios to
understand the relative differences in cost between various design options.
• Provided recommendations on implementation strategies for future road elevation and
drainage improvements.
Part I of this Final Report includes a thorough discussion of the data collected, analyzed and used
to develop a technical recommendation for road improvement projects in the Twin Lakes and
Sands Communities that can also be applied for other road improvement projects. Stormwater
solutions and designs are discussed as well as local factors that may influence design options such
as elevations of adjacent properties and impacts to environmentally sensitive lands. Ultimately
Part 1 of the Report provides a technical basis for harmonizing future sea level rise impacts and
a threshold for flooding (in terms of days not exceeded) that can be replicated. Appendix 1
supports the implementation of the Technical Recommendations in Section 4.5 and creates a
standard methodology for developing the elevations of future road improvement projects based
Janua!y 7 0 "7 ?age
Monroe County Pilot Roads Project Twin lakes ord San Communities
Final Report
on 1) a future sea level rise projection and 2) not exceeding a certain number of days of flooding
annually. Combined these two values create the target design elevation outlined in the Appendix
1 methodology.
Part 2 of this Final Report includes a legal and policy overview including the state of the current
law related to infrastructure, flooding and sea level rise implications. Applicable state law and
case law are analyzed to answer questions related to a local government's duties for levels of
service related to roads. An overview of case studies from other local governments (and agencies)
that have begun to address levels of service related to flooding or future flooding, and have
adopted policies doing so, is included in Part 2. Appendix 2 has been developed as a Draft
Ordinance for future consideration in adopting this policy framework. Drawing upon the legal
and policy foundation, and applying it to the technical work performed in Part 1, a policy
framework is described which is based on a three - pronged approach to:
1. Define a target "Design Criteria"
2. Evaluate a list of Local Conditions that may affect implementation
3. Create a designation for areas where the design criteria cannot be met
In Section 4.5, the Final Report includes recommendations for elevations in the Twin Lakes
Community in Key Largo and the Sands Community in Big Pine Key as follows:
• In the Twin Lakes Community, the recommendation is that portions of the roadways be
raised to approximately 5" of elevation NAVD88 (4.4 inches as noted in technical material)
to provide flooding relief, and extend the life of the road to 2040.
In the Sands Community, the recommendation is that portions of the roadways be raised
to approximately 11" of elevation NAVD88 (10.3 inches as noted in technical material)
based on a similar assessment.
The full list of steps in the Methodology can be found in Appendix 2 to arrive at these
recommended elevations. When accounting for sea level rise and a point at which flooding does
not exceed 7 days annually, the data resulting from evaluating the 6" and 12" scenarios identified
in Section 3.3 show a conceptual picture of what elevating to 5" and 11" will actually require. In
summary:
Note: Scenario Considered means the scenario evaluated in this analysis that is the closest to the
recommendation when applying the Methodology in Appendix 2.
Finally, the GreenKeys! Sustainability Action Plan (accepted by the Board of County
Commissioners in April 2016) includes recommendations that support this Pilot Project, and also
recognizes that a larger countywide roads effort is needed to fully understand the planning and
Page 2 January 7 0" 7
Scenario Considered
Elevation Length
Conceptual Cost
Recommendation for Twin Lakes
6
.3 Miles
$0.92 Million
Community in Key Largo of 5"
Recommendation for Sands
12"
.34 Miles
$2.63 Million
Community in Big Pine of 11"
Note: Scenario Considered means the scenario evaluated in this analysis that is the closest to the
recommendation when applying the Methodology in Appendix 2.
Finally, the GreenKeys! Sustainability Action Plan (accepted by the Board of County
Commissioners in April 2016) includes recommendations that support this Pilot Project, and also
recognizes that a larger countywide roads effort is needed to fully understand the planning and
Page 2 January 7 0" 7
Monroe County Pilot Roads Project Twin I akes and Sands Communities
Final Report
economic implications of comprehensively planning for future County road improvement
projects. Lessons learned from this effort have been valuable, but the larger County effort will be
better able to provide the information needed to support a fully developed capital planning
program going forward. That said, this Pilot Project, and the specific recommendations identified
for the two communities resulting from it, serve as a basis to move forward to the design and
implementation phases. This will continue the process of developing valuable results- oriented
information for future use.
JaILary 7017 1 D�.ge
Monroe County Pilot Roads Project Twin lakes and Sands Communities
Final Report
2 Introduction
Monroe County accepted the GreenKeys! Plan in early 2016, which made several
recommendations concerning infrastructure planning in light of future sea level rise. The County
also experienced flooding from higher-than-normal King Tides in 2015 and 2016, causing
extended periods of flooding in some communities along the Keys. King Tides refer to the higher-
than-average annual high tides that occur in the Fall each year when the moon, sun and Earth
are aligned in such a way that gravitational forces produce the greatest tidal fluctuations. King
Tides generally provide a preview of what the County can expect as sea levels continue to rise,
but the levels experienced in 2015 were particularly high and resulted in a visual indication of
what types of impacts will be seen in the future. These King Tide impacts will also be exacerbated
by higher sea levels. Knowing that increased flooding from King Tides, storm events and general
sea level rise will likely occur in the future, and that the County will have to address this issue
countywide,the County moved forward with a "pilot effort."The goal of this pilot effort is to test
methodologies for determining future flood risk scenarios and to develop a policy framework for
making these decisions relative to new roadway improvement projects. Two communities were
chosen for this study, one in Key Largo (Twin Lakes Community) and one in Big Pine Key (Sands
Community). Figure 1 below identifies the locations of the two communities chosen. Specific
roadway areas within those communities were further defined as the primary area of focus (see
Figure 2 and Figure 3).
Figure 1 - Communities Selected for the Pilot Project
i ‘ -c'A :111/1;
c l
. .. a- -. k:ey Le'go
q ' ,Key largo-
L /v
4 ,.. -
g
ii
LI "
v
;�
81 Big Pine Key
C>a
\ `!„ ..
fah4. .�
IMEMO Lenasai
Key West 20 6 Googie Go•:le eart
t
Monroe County Pilot Roads Project Twin lakes and Sands Communities
Final Report
Figure 2 -Study Location - Twin Lakes Community, Key Largo
e j6
t
- ,
= i# ' * '
, . ;
, . .
llt- 1':-•'' ,
•iiii .. ii, 'Pe; 0,0., '
• 2 le -- , , ,.1 . ...Nth,
.ii,„; % s•..r.•-.to„--7. criisiatv _ Vo„j., Ilan ta Are'Y•
r 41kec egitsAl_ . ., 7-.,tv, cl'',4 *- •
t.'m Pi foto! , " -z, .'
ia, . . ..,.rt-T . .. ,v4,.. GlItrqt•:. . .
...
• ,co 41 ,I 1* • 1
r 44,0 ,,,_ ...
— 4
,t • Ili-. -,L,ft.C1-2./ i oilins :- , . , *••
• /1! 1116:„11(3. •;fr/Sh
;IP c°. *7 , InSbun,,ii.J.Dr,
'Dr ''S` 'IV- .
, 4,"•
gi. wn_3?.• u, • 4, 7 .
CO 1 ta"; s' ,-, - •
1'
,,,, vikl•1 bil" k
S.
a .'
kt-St \7 (/ s-. Go(
—,--itrAnti-V6 25°0806 40-N BO 2401 38..a.ele,
Figure 3-Study Location-Sands Community, Big Pine Key
1.
- ----I ' - - - ii,
..,.51—pwRa. r- - • I' s
-
4.1 let 4111....4 iv.-: . liAsliznif‘_--,_.
-'-' f okie... 4: IP • • 'I"'W,."
.?• 4 1 4 '
c. •2 ../ ••.g '. .. ',
'
ye • •' '' -", .,.., a
Lt.._ ,...L.
li • •
ri---i Jo
r ' ' •• I t kfi iitureff•iiii
isi-s17 o • y,'IP -"Ft.yrtaillitp
4' 40.41.. , 4, , t 4 •, ir 0
•'Edvisar•d•Rd ..."""
..•iv,- g',1. r . .
2ntl-Ln -.. ..... ,
A •O• Ar I 14. I* AM,ii 10,•••• •.- .
• FiltrIOC 1,9 ' ts......:U 1 .. 1,E,i,
g .-..:MI - 1...44,• .., •.t.ggAl to. vs, . i . 0. ....,
.........• II° . 4 .. '
. ;(1) • • 41 I I . g•t II 4-•Il •
. ...)-27,1 _ ........" • • a It .1.a• 0 4 i I Ati s
A
4 It,I'n ••.. :- r• c •-." 0. i . ..„ I. .-. ....•I I•.s'7.1/....I •
.tJ •
c ••••. • a . •
.. t.;L.' . i JE ., .. '"''' ‘, . • i .F 4•14-— ..
• . .1 •.1, - - . ....,,,...,, ., .or.
:s - vij 143
:i. ne K- ' . '1.- /11!A T. II f', --- . 'il 4. ell—
...
Ski s w, — , „, [" . ' e-At
•.?
6,-
. ,
%lir'
.._----•-• ... k...41 l ..,..
I A',
Sin-Ave r„...,=,e?.,....2 fol. .11, ,, t,4!-•
zr • I-4, - k.1,00
- .0
, ifrieV t,
Illibit
. 1 2 4 4 0 4 5 68 Ner 7. •• jley in ••• • Eye
Monroe County Pilot Roads Project Twin I okes and Sands Communities
Final Report
County road improvement projects should consider the following questions:
• How are levels of service established in the face of uncertainty with a changing climate
and projected levels of sea level rise that are based on a range of future conditions?
• What is a reasonable level of service for County road projects impacted by flooding and
the amount of time a given road is inundated?
• What would be considered a cost - effective response given the needs of these
communities now, the broader needs of Monroe County in the future, and the limited
resources the County has or will have to address capital improvements?
• What is a model policy approach for future decision - making on road levels of service
countywide?
Part I of this report presents the history of, and the technical work performed for, the assessment
of the potential responses to tidal flooding in the two County communities. This work reflects
pertinent GreenKeys! Plan recommendations to better plan for future road flooding risk. The
focus of this effort has been to develop a method to estimate future tidal flood potential, based
on analyses of historical events and projected levels of sea level rise, as well as develop
conceptual design and cost estimates for road and drainage improvements in the two
communities.
Final designs for these two communities serve as a pilot effort to take lessons learned from this
process and extend them to other County road improvement projects. The analysis for this
project is specific to the two pilot communities: Twin Lakes Community in Key Largo and the
Sands Community in Big Pine Key.
Part II of this report includes a legal overview of the duties and responsibilities for local
governments to maintain and upgrade roads, as well as an approach for a policy direction,
outlining a set of factors for the County to consider in establishing service levels for future flood
risk related to road projects. Many of the outcomes of this project may be translated to other
road improvement projects, which is why a comprehensive policy addressing future sea level rise
in road design projects is also included.
The GreenKeys! Plan indicated that approximately 144 miles of roadways may be exposed to
nuisance flooding by 2030 under the "low" sea level rise scenario (3 -7 inches), and that 188 miles
of roadways may be exposed by 2030 under the "high" sea level rise scenario (9 -24 inches).'
Thus, design criteria will need to consider a larger countywide need to assure that appropriate
sea level rise impacts are considered as part of project decision - making, as well as include the
challenge of limited resources.
1 Note, these sea level rise scenarios modeled in the GreenKeys! Plan, were based on those being utilized at the time by the
Southeast Florida Regional Climate Compact. Those scenarios were utilized from 2010 -2015 and were updated using a different
methodology by the Compact in 2015. For the purposes of the GreenKeys! Plan analysis identifying road areas to be impacted
by nuisance flooding in 2030, the difference between the previous and current sea level rise projections being used by the
Compact is de minimis.
P a g e 6 J a n u a y 7 0 " 7
Monroe County Pilot Roads P roject - Twin takes and Sands Communities
Final Report
Recommendations from the GreenKeys! Plan relevant to this study include:
• 1 -19, "Pilot project to conduct Comprehensive Feasibility Study for Enhanced Stormwater
and Tidewater Criteria (prioritizing areas) for near -term areas subject to inundation risk,
including nuisance flooding (in two locations).
• 2 -14, "Conduct a countywide roads analysis to identify near -term roads subject to
inundation risk, including nuisance flooding. This will include researching where related
green infrastructure would be appropriate. Increase the percentage of funding invested
in green infrastructure."
• 2 -36, "Ensure that all new nuisance flooding data informs future road decisions. These
data will also need to be considered for future road decisions. This will require
coordination with FDOT for impacts to State Roads (U.S. Highway 1).
The technical analysis in this project can be used as a framework to make future road
improvement decisions. The steps or tasks undertaken to complete this work are shown in Figure
4. In essence, the analysis reviewed existing tidal flooding over the past 20 years, incorporated
rising water levels associated with sea level rise, determined how roadway design factors may
have to be modified due to changing future conditions, considered use of limited resources, and
then summarized how that information could be used to guide County policies.
Figure 4 - Project Technical Work Flow
Study Past
Events and
Determine
Flooding
Recurrence
Consider Sea
Level Rise
Estimates for
the County
Develop Identify Design
Engineering Alternatives
Response Response for
Strategies w/ Communities
Estimated Costs
Ja - nary 7017 1 age 7
Monroe County Pilot Roads Project Twin lakes and Sands Communities
Final Report
3 Part I: Methodology and Technical Background
Study Past
Events and
Determine
Flooding
Recurrence
3.1 TIDAL FLOODING ASSESSMENT
The purpose of the first task to "Study Past Events and Determine Flooding Recurrence" was to
conduct an analysis of past tidal events that occurred in the study areas to develop an
understanding of how tidal influences and events have affected the two pilot communities. The
intent was to develop a data-driven assessment based upon past events and inform decisions on
how the County may respond to similar events in the future. The assessment focused on
determining how past events, including the events that occurred in Fall 2015 and 2016, should
be considered in terms of understanding how tidal and other flooding events have impacted
Monroe County communities.
,• -w p. µ
• • r, .
4004 of to SCdre- a sm
_ Presented as Concept Only
-20
A Note about the Vertical Datum Value Used in this Report
A vertical datum is a reference measurement to identify elevations in comparable units from around the world.
The units used in this report are for the North American Vertical Datum from 1988—or the NAVD88 datum.
One interesting thing to note on the use of this datum is that for many points in the Florida Keys,the measure
for Mean Sea Level is less than zero. The graphic above identifies how the relative measures of elevation can
be considered, with elevation 0 being the low point of the roadways in the two communities. In the Sands
Community,an elevation of 0 is near the intersection of Avenue J and Father Tony Way and in the Twin Lakes
Community,elevation 0 is near the intersection of Shaw Drive and Crane Street.
The water elevation data reviewed included a summary of tidal events from the Vaca Key
National Oceanic and Atmospheric Administration ("NOAA") Tide Gauge 20 year tidal record to
complete an analysis of tidal flooding events in the County. The Vaca Key Gauge was used
because it is the most proximate to both study areas. The work included an assessment of the
extended period of record for the Vaca Key Tide Gauge, which is shown in Figure 5.
, -
Monroe County Pilot Roads Project - Twi I okes and Sands Communities
Final Report
Figure 5 - Voca Key Tide Gauge Water Level -1996 to 2016
Hourly Water Level
Vaca Key, Station 8723970
5.5
5.0
4.5
4.0
3.5
3.0
m 2.5
Z
2.0
r
1.5
d
d 1.0
3 0.5
0.0
-0.5
-1.0
-1.5
_2.0
-2.5
Hurricane /
Wilm
Aiii
W �J
rl J . I ,.
r .J. .,�L A
00 O O N N QQ aa - - - - - O - N - V �
O O 0 \ \ O O \
- -
The analysis also reviewed data related to the Fall 2015 flooding event and the factors that went
into the flooding caused by that event. The tidal record for that event is included in Figure 6. One
primary conclusion from the review of the Fall 2015 event is that the weather conditions in the
region resulted in shifting the average tidal conditions significantly higher for numerous days over
the month. This means that during the events noted in the two pilot communities, the overall
tidal effects shifted higher by a few inches, resulting in low tides during this period not low
enough to clear the flooding experienced. The visual effect was extended periods with tidal water
on community roadways. While Fall 2016 was a more recent King Tide event, Fall 2015 was
chosen because predicted and observed water levels were higher, reflecting a more extreme
condition for comparison purposes and alternatives evaluation.
A statistical analysis was completed for the 20 -year tidal record to develop an understanding of
the effect of past tidal conditions on flooding in Monroe County. This was done to further
characterize how tidal events, even those affected by non - hurricane conditions, have impacted
the two communities over the past two decades creating a baseline. This baseline assessment
acts as a point of reference to project forward into the future while also considering sea level rise
effects on these conditions.
J a❑ u a y 7 0 1 7 n a E, e 9
Monroe County Pilot Roads Project Twin lakes and Sands Co mmunities
Final Report
Figure 6 - 2015 Tidal Record for Voca Key Tide Gauge — Highlighting 2015 Event
De- trended Water Level
Vaca Key, Station 8723970
ss
5.0
4.5
4.0
3.5
3.0
1 2.5
a 2.0
z
y 1.5
1.0
m
3 0.5
i
0.0
-0.5
-1.0
-2.0
-2.5 .. - - -- — ..___. J
O O Of 00 00 I� n
m a v
N tp n 00 O O M N
r1 N
Note: The graphic above depicts the tidal record for the year 2015. The title of the figure
identifies "de- trended" data which describes a method applied by the Team to clarify the
tidal effects over the 20 -year period, in part by removing the incremental sea level rise that
occurred during that period. The time period between the two red lines is the start and end
point of the 2015 event described throughout this report.
Table 1 shows the results of the initial analysis performed for this report, outlining the work to
identify return period events and flood levels for the two pilot communities. Some notable
differences in the table are attributable to the overall tidal effects in each area —with the tidal
values being generally higher for Big Pine Key based upon its location, and less for the Key Largo
community.
The information in Table 1 outlines the number of hours of flooding at various elevation levels
for the two communities, converting those values into hours of inundation, which is then
averaged over the 20 -year analysis period to identify flood probabilities. As an example, a flood
level of approximately 1.7 inches (NAVD88) at the Vaca Key Tide Gauge translates into
approximately 7 days of flooding per year (24 hours of flooding), which is used as a metric in later
design steps of the project. The values highlighted in green are used as input on future design
decisions.
P a g e 1 0 1 , a n L, a- y 7 0 1 7
Monroe County Pilot Roods Project - Twin Lakes and Sands Communities
Final Report
Table 1 -Analysis of Tidal Water Levels for the Vaca Key Tide Gauge and Estimated Levels for
Two Pilot Communities
Vaca Key Twin Lakes Sands Twenty Year Record Average Per Year
Water Water Water
Level Level Level Number of Number of
(in, (in, (in, Floods Inundation Floods Inundation
NAVD88) NAVD88) NAVD88) (#) (hr) (#) (days)
-1.3 -4.0 1.9 159 16,416 8.1 35
1.7 -1.0 4.9 45 3,600 2.3 7
4.7 12 744 0.6 1.5
7.7 5.0 10.9 2 120
Note: The first column shows various water levels at the Vaca Key Tide Gauge. The next two
columns show when flooding occurs in the community, but due to differences in elevation,
topography, etc.,flooding occurs at different levels. The negative values are in relation to the
NAVD88 datum, where zero is a point approximately equal to the low point of the roadways in
the two communities.
3.2 CLIMATE CHANGE AND SEA LEVEL RISE
Study Past Climate change is a term used to describe
Consider Sea warming of the Earth's atmosphere, which
Events and Level Rise changes weather patterns and alters the physical
Determine » Estimates for conditions of the Earth. One such change resulting
Flooding
Recurrence the County from atmospheric warming is sea level rise, which
occurs due to ice melt, thermal expansion of
water, and other factors.
A concern in Monroe County,as a coastal community, is the long-term effect of rising sea levels.This
changing condition, combined with porous geology and tropical weather patterns, makes Monroe
County unique in its greater exposure to long-term sea level rise risks. The challenge will be to
develop policies that respond to these changes while recognizing the timing and uncertainties
associated with such future conditions, as well as limited resources to address these issues.
Monroe County is part of the Compact, which provides information to help local government
decisions throughout the four County lower east coast region. The Compact released in late 2015
a document that outlined updated sea level rise values for three scenarios in southeast Florida2.
These curves are noted in Figure 7. The challenge of using three potential future conditions,
particularly with regards to infrastructure planning, is that there is the possibility of overspending
or underspending on improvement or protection strategies depending on which scenario is
selected, and which level of sea level rise actually occurs. In reviewing Figure 7, one can see that
building to the NOAA High scenario in 2040 may be overbuilding to conditions not expected for
2 Unified Sea Level Rise Projections—Southeast Florida,October 2015.
1 7 r 1 1
Monroe County Pilot Roads Project Twin I okes and Sands Communities
Final Report
30 -40 years should the IPCC AR5 Median scenario be followed more closely. Decisions that
recognize this reality and identify how to spend scarce resources in the face of conflicting needs
are important in the context of planning for sea level rise.
Figure 7 - Sea Level Rise Projections - Southeast Florida Regional Climate Change Compact
80
Unified Sea Level Rise Projection
(Southeast Florida
Regional Climate Change Compact,
2015)
70
LL
IPCC AR5
USACE High
NOAH High
(,r,
Year
Median (inches)
(inches)
A
' (inches)
a �
i
c E
2030
6 i 10
12
{
_
° 40
2060
14 26
34
2100
31 61
81
J {'
26"
>
�.
USACE intermedlatet NOAA ime—diate Lo
0
1119) 1000
201(! 1070 70i0
7040 /0 20NI 7010 20SO 7090 71(K)
Year
Another primary consideration in making infrastructure decisions is the life expectancy of a
project. Adopting an expected project "useful or design life" ensures that investments consider
how long an asset is expected to be in place before future replacement or improvement cycles
are necessary, or how long an asset may have before being impacted by changing environmental
conditions. This is an important perspective, as every infrastructure project should consider not
only the point of impact, but also the implications of that impact on the facility, or the remaining
design life. These are factors that are not a part of traditional facility design.
Data analysis was conducted to develop estimates for how sea level rise would potentially change
the design approach for raising the roadways in the two communities, primarily by incorporating
future sea level rise projections into decision - making. The Compact generally recommends that
the IPCC AR5 Median and USACE High scenarios be used as a range for more common
infrastructure planning decisions. Decisions for infrastructure or facilities with a very low
tolerance for flood exposure (such as power plants) should utilize the NOAA High scenario as
recommended by the Compact. For this analysis (given the routine nature of road
improvements), the two recommended estimates for sea level rise of the IPCC AR5 Median and
USACE High scenarios were applied to the end of the 25 -year design life used as an estimate for
the Pilot Project. Twenty -five years was chosen as the typical useful life for a road improvement
project.
P a g e 1 i I J a n„ a- y 0 1 7
Monroe County Pilot Road Project Twin lakes and Sands Communities
Final Report
Estimates of sea level rise increase from the current 2015 levels by 5.4" (2040 AR5 Median
scenario) and 10.1" (2040 USACE High scenario) by 2040. These values were added to information
taken from the tidal records to develop a table of water elevations associated with various tidal
inundation events that would be considered for a future design response. Table 2 identifies the
calculated values for a set of events taken from the tidal record, adds the sea level rise estimates,
and identifies the water elevations to be considered as a part of roadway and drainage design for
this project.
Table 2 - Tidal Condition and Flooding Estimates for Two Communities for Two SLR Values
Note: This table highlights the negative values associated with NAVD88 elevations in the study
area. Reviewing the data to note changes or differences in elevations and to identify elevations
that address certain flood recurrences is the best use of the table.
This data formed the basis for design recommendations that were developed and assessed for
this project, a process that is outlined in the next section of the report.
3.3 ENGINEERING DESIGN ASSESSMENT
Study Past Events
and Determine
Flooding
Recurrence
Consider Sea Develop
Level Rise Engineering
Estimates for the Response
County Strategies w/
Estimated Costs
The next Task performed was the "Development of Engineering Response Strategies with
Estimated Costs." In order to identify a set of design scenarios that could address current and
potential future conditions as a means of defining the benefits and cost of strategies that would
address long -term sea level rise and tidal conditions. This was an important consideration, given
that conditions present in these two communities will be similar to others in the County.
1 a n u a y 7 0 1 7 ! P a. g e 1 3
Existing
Future Design Levels Considered
Values (in. NAVD88)
2040 Median SLR
(in.)
2040 High SLR (in.)
Big Pine
Key Largo
Big Pine
Key Largo
Big Pine
Key Largo
Mean Sea Level
-9.0
-11.0
-3.6
-5.6
1.1
-0.9
Mean Higher High Water
-1.1
-7.0
4.3
-1.6
9.0
3.0
2015 Event Avg. Elevation
5.3
3.3
10.7
8.7
15.3
13.3
2015 Event High Elevation
16.1
14.1
21.5
19.5
26.1
24.1
Est. Month Flooding
1.9
-4.0
7.3
1.4
12.0
6.0
Est. Week Flooding
4.9
-1.0
10.3
4.4
15.0
9.0
Est. Day Flooding
7.9
2.0
13.3
7.4
18.0
12.0
Note: This table highlights the negative values associated with NAVD88 elevations in the study
area. Reviewing the data to note changes or differences in elevations and to identify elevations
that address certain flood recurrences is the best use of the table.
This data formed the basis for design recommendations that were developed and assessed for
this project, a process that is outlined in the next section of the report.
3.3 ENGINEERING DESIGN ASSESSMENT
Study Past Events
and Determine
Flooding
Recurrence
Consider Sea Develop
Level Rise Engineering
Estimates for the Response
County Strategies w/
Estimated Costs
The next Task performed was the "Development of Engineering Response Strategies with
Estimated Costs." In order to identify a set of design scenarios that could address current and
potential future conditions as a means of defining the benefits and cost of strategies that would
address long -term sea level rise and tidal conditions. This was an important consideration, given
that conditions present in these two communities will be similar to others in the County.
1 a n u a y 7 0 1 7 ! P a. g e 1 3
Monroe County Pilot Roads Project Twin I okes and Sands Communities
Final Report
Flood Levels and Recurrence
The Team evaluated not only a particular level of sea level rise by 2040, but also a range of
flooding days annually at a given flooding level. The goal is to provide information related to each
flood level scenario that tracks the amount of time that level will occur in any one year. Flooding
on a road for 30 days in one year versus flooding for 7 days or a single day creates a very different
impact on the community, so the "days of impact" are also considered over a range of options.
King Tides of 2015 and 2016
In the fall of 2015, both pilot communities experienced levels of tidal inundation over numerous
days due to multiple factors. The primary effect was the time of year, when October typically
brings the highest King Tides. Additionally, this effect can be compounded by wind - related
impacts or surge from events such as tropical storms or hurricanes. In terms of comparing known
flooding conditions in both the Fall of 2015 and 2016 within the two communities, NOAA data
from the Vaca Key Tide Gauge show that flooding levels in the Fall of 2015 were on average
greater than 2016, so the Fall 2015 was chosen for a comparison between sea level rise scenarios
and a recent event - driven impact. Anecdotal information supplied by area residents noted that
the Fall 2015 condition had not been seen before (the extended period of flooding) and historical
data shows that level had a very low probability of occurring (less than 3% in any given year). But
given the fact that people saw the impact of that level of flooding, scenarios were developed and
compared to this condition as well as future sea level rise scenarios. Part of the comparison
includes what relief various alternatives might provide against this extreme condition.
Design Scenarios
The focus of this Task was also to develop multiple design scenarios for raising the roadway to
address tidal flooding issues. The intent of identifying varying roadway elevation scenarios that
would address several inundation levels was to pursue an option which would avoid flooding and
develop a stronger understanding of the cost variations for each design alternative. The Team
selected elevations that would be sufficiently different, as to enable comparison of options to
address flooding and to compare project costs associated with the different flood levels. For this
exercise, the following road elevations were tested: 6 ", 12 ", 18" and 28" (NAVD88 elevations),
meaning all roadways in the study areas lower than these elevations would be elevated to these
various levels for analytical purposes. As a reminder, the relative low point in each community is
approximately elevation 0" in NAVD88 meaning that increasing elevations by 6" translates to
those areas being raised by a comparable amount.
Table 3 and Table 4 represent the range of conditions based upon the use of the 2040 sea level
rise scenarios for the IPCC AR5 Median and USACE High estimates. A number of considerations
are important when looking at these tables:
• The columns represent the duration of water elevation conditions for the scenarios
shown. Mean Sea Level and Mean Higher High Water ( "MHHW ") represent a general sea
condition and average high tide respectively. This is followed by the calculated analysis
results of recurrence of flooding elevation ranges from 30 days down to 1 day annually.
PaFe 14 ancary 7017
Monroe County Pilot Road Pr oject — Twin Cakes and Sands Communities
Final Report
e The Average Fall 2015 event column shows the calculated average level of flooding that
occurred over the duration of the "King Tide" event in 2015 from September 24 to
October 31
• The Max Fall 2015 event column shows the highest level the water was recorded around
October 4th during the 2015 King Tide event.
• Rows represent the following:
— Row 1— current estimated flood levels from the 2015 Tidal Record, providing a
"base condition" for comparison with the IPCC AR5 Median and USACE High sea
level rise scenarios.
— Row 2 — those same calculated flood levels, but with each value having been
increased by the sea level rise estimate to occur between now and 2040 for the
IPCC AR5 Median scenario (5.4 ").
— Row 3 —flood levels in row 1 increased by 10.1 ", which is the estimated sea level
rise value from between now and 2040 for USACE High Scenario.
Numbers within Table 3 and Table 4 represent the inches in elevation of the water levels, in the
tidal datum NAVD88 values. Negative values are presented as noted throughout the report due
to the NAVD88 reference and the fact that many areas of coastal Florida are at a level below that
base elevation. The base level for community roadways generally range from 0 to over 28" above
NAVD88, as can be seen in Figure 10 and Figure 11.
Table 3 - Tidal Water Elevations and Recurrence Periods for Big Pine Key
Sands Community, Big Pine Key
All Water Levels Shown in Inches NAVD88
MSL
MHHW
30 Days
Annually
7 Days
Annually
1 Day
Annually
Avg. Fall
2015
Event
Max Fall
2015
Event
2015 - Tidal Record
-9.0
-1.1
1.9
4.9
7.9
5.3
16.1
2040 Med SLR ( +5.4 ")
-3.6
4.3
7.3
10.3
13.3
10.7
21.5
2040 High SLR ( +10.1 ")
1.1
9.0
12.0
15.0
18.0
15.3
26.1
J a n u a y 7 0 1 7 F a g e 1 5
Monroe County Pilot Roods Project Twin I okes a n d Sa Communitie
Final Report
Table 4 - Tidal Water Elevations and Recurrence Periods for Key Largo
Twin Lakes Community, Key Largo
All Water Levels Shown in Inches NAVD88
MSL
MHHW
30 Days
Annually
7 Days
Annually
1 Day
Annually
Avg. Fall
2015
Event
Max Fall
2015
Event
2015 - Tidal Record
-11.0
-7.0
-4.0
-1.0
2.0
3.3
14.1
2040 Med SLR ( +5.4 ")
-5.6
-1.6
1.4
4.4
7.4
8.7
19.5
2040 High SLR ( +10.1 ")
-0.9
3.0
6.0
9.0
12.0
13.3
24.1
Note: The tables show those values for some key conditions or return period events that were
used to derive potential roadway design levels that matched predicted water levels. It is similar
material to what is presented above, but reoriented to show various water levels. Negative values,
as noted throughout, are a result of the elevation datum applied on this project. The reader can
review the table to note conditions that would be addressed through building the roadway to a
certain elevation. As an example, building the roadway to an elevation of 6" NAVD88 would be
higher than the calculated average 2015 event elevation in both communities (3.3 inches in the
Twin Lakes Community and 5.3 inches in the Sands Community) — meaning the low tides would
enable the water to clear from the roadway.
Stormwater Management
Another element of roadway design is stormwater management, which will be required to meet
state and federal water quality standards. Elevating road levels will protect against various tidal
flooding events, but areas surrounding roadbeds will need proper drainage to manage
floodwaters and stormwater runoff and prevent adjacent properties from flooding.
There are various drainage infrastructure options available for roadway improvement projects, such
as French drains, injection wells, or oil -grit separators and pumping into surface waters. Ultimate
design is dependent upon a number of factors such as the space available, water quality
requirements, cost effectiveness, service requirements, groundwater levels, and soil permeability.
These factors limit the types of designs that can be implemented in various areas. For example,
higher groundwater levels and poor soil permeability in low lying areas will limit the feasibility of
French drains and injection wells. These conditions are expected to deteriorate with rising sea levels,
as encroaching ocean water will raise the water table and reduce drainage capacity of these types of
systems. In these cases, pumps would likely be required to move the runoff out of the area. Due to
local water quality and permitting requirements, this water would need to be treated before release.
Figure 8 below identifies the type of stormwater infrastructure recommended in the two pilot areas,
recognizing that other treatment types may be more applicable in other areas.
Pumping and treating stormwater runoff also requires additional infrastructure such as an
emergency generator and control box to ensure operation in periods of loss of power. This
condition is depicted as seen in Figure 8. This same type of design is already in use in Big Pine Key
for wastewater and an example of a control box can be seen in Figure 9. The generator and
F a g e 1 6 1 J a n u a r y 7 0 1 7
Monroe County Pilot Roads Project Twin lakes and Sands Communities
Final Report
control box are placed along the roadway, with the generator placed above the Base Flood
Elevation as identified by the Federal Emergency Management Agency ("FEMA").
Figure 8- Storm water Pumping Equipment
I.
.40' r. 4, I r Generator
0 P 1,
' ' Control Box
...::r,.4.,
ilk
...,,,,... 11,Vr •-;U:'‘ ' *, -4, • ,
! „t ..
ie i
. , .... NI
I ._.............R MOM
I
Higher Groundwater Table from SLR will Limit
Drainage Capacity of Soil in low-lying areas
Figure 9- Control Box-Big Pine Key
• Note: Pump stations
11.; )!^ for wastewater
F
��- " � system are similar in
air.
N �= termselevation
' • ;� r - of el ti
t
, and location of the
1I ,: - u actual pumps,
I
I ' • ` ii P. } - generator and
a, �i control panel to
I,y` ,� . x • `'' avoid flooding
•4 4
;" impacts.
a.
•
't , i t l: ..K.ei' '' -i.
r 1 -
Monroe County Pilot Roads Project Twin Lakes and Sands Communities
Final Report
For a full description of stormwater management design options available on other similar
projects, see Section 4.3 Stormwater Management Design Alternatives and Recommendations.
Development of Estimated Costs
Estimated costs for raising the roadways were based on cost data maintained by both the County
and Florida Department of Transportation ("FDOT") for local roadway construction projects. It is
important to note that the two communities have areas of varying elevation along the roadways
in question.That is,the effort to raise roadways to meet a desired elevation would be in sections,
not as one continuous effort, or as each alternative is evaluated for a higher elevation, more
length of the roadway needs to be elevated.
Figure 10 and Figure 11 have been prepared to show how the elevations in the communities
match the chosen design scenarios (6", 12", 18", and 28") and indicate with colors the elevations
in each community that are lower than these values. This reality has implications when
considering the design response to varying water levels. Specifically, designing the roads in the
community to ensure that all roads are at least at elevation 6" results in a need to raise certain
portions of the roads (0.28 miles in the Sands Community, and 0.3 miles in the Twin Lakes
Community). Or,when considering raising the roads to a higher elevation such as 12",this means
that the roadways included in the 6" section will need to be raised to 12", but other additional
roadways will also need to be raised to reach that elevation.
Raising roads in the communities to reach 18" or 28" of elevation would also have an expanded
roadway length that would need to be raised to reach those target elevations. Therefore, each
subsequent move to raise roads to a target elevation means that this changes the elevation, but
also the extent (linear mileage) of roadways that would need to be improved. This condition is
generally represented in Figure 10 and Figure 11 showing how incremental increases in design
heights also require increases in the lengths of roadways that would need to be reconstructed to
address those identified flood elevations.
Figure 10 - Current Elevations in the Twin Lakes Community
r Pe.... I mi Wow
1111r •.y f
A '+ v...nrw Ono
f
r-r -
Gr' 'It; �J ��1. ri
3 "4w
' ,la t
•
•` ,
wo„ s t , -.1 ' • • 9h M. ..r ' ii, i iii`N r•:,• Roadway EIevatan
t*t 'M A Ws, • 4 K ," �i, t,4. y Inches NAV08i
r1 .J>~ '40. r 1igt, I.•" - i 1:. "•• *rip it ,4
*. • ar .
I►i r t ... T" •• ,4 11 N 6-1Y
�' '� �.r r : .R rri . ' A( • .
!. I''1' i > yjtt - _ 12-16'
{ ' f I ! h 4 11►'I ,
Y s ! r ',1 t <"1 _ 18-2r
:411 ',,i- , .:`. ri 44,1 *.-- 4r :4‘, A -- :
fP I p .
..it,t , .;,, , , Airs' irc. - VI ilk ii
_ X1641,41 k le%
1 1
Page 38 I January 2 0 1 7
Monroe County Pilot Roads Project Twin Lakes and Sands Communities
Final Report
Figure 11 - Current Elevations in the Sands Community
lizie4...j A� .`71M...,"�••Ion 1••.
r. .-•.a.
. t
34110 i .
i f hill Or le Y .1 lioadwey newscast
Inches MAW=
t eigritfi it Ki . sPlawswe 11,
1 .Iflilf t •i.r,,f--1N <6•
r�, i t 'ill' it #114 All � _ 6-1r
t;1 ,! fiP t•. ! re cat�► Ur' 11 1011111114111
12 18
liitiotuimE
- '.T;,i,a • ''I44,0,0r LInr vi t '13 sgraa ma18-2r
y p t s
riiimeir
l _ *. 0 I i s,it.• a iry,
1.111111
w` •1. w 1 sit r-I-r+-rT�ri
s �•w+. a
Estimated costs for elevating the roadways in the two communities were developed based on
information provided by Monroe County and a review of construction costs for other similar local
projects. Table 5 summarizes the cost estimates for raising the roadway profiles identified within
the pilot area for each community.
Table 5 -Cost Estimates for Reconstructing Roadways in the Two Communities
Twin Lakes Community- Key Largo
Length of Roadway Requiring an Elevation Increase Total Elevation / Reconstruction
for Noted Water Levels Cost
6" 0.3 miles $0.92 million
12" 0.7 miles $4 million
18" 0.77 miles $5.8 million
28" 0.91 miles $7.3 million
Sands Community—Big Pine Key
6" 0.28 miles $2.22 million
12" 0.34 miles $2.63 million
18" 1.29 miles $8.9 million
28" 1.46 miles $10.5 million
1 7 1- E- 1
Monroe County Pilot Roods Project Twin I okes and Sands Communities
Final Report
The engineering work to develop the estimates for construction are noted in the attached
appendices and are included for reference.
The cost estimate includes a full range of construction - oriented costs including:
• Maintenance of Traffic
• Mobilization
• Design
• Construction
• 15% of costs for Construction Engineering and Inspection
• A 25% Cost Contingency
• Stormwater capture and treatment measures, as required by law
The cost estimate did not include the following:
• Right -of -Way impediments or acquisitions
• Land purchases
• Driveway Improvements
• Legalfees
Local Conditions which Constrain Road Design
While cost is an obvious constraint on road improvement projects, there are additional factors
which can affect project design and the implementation of a desired roadway improvement
project. These factors are often external to the direct implementation of the project, have an
impact on how the final project design is developed, and how the improvement is built, and also
must be addressed collaboratively with stakeholders and property owners.
For example, a road improvement project such as raising the road may require widening the road
and could cause encroachment outside of the available public right -of -way ( "ROW ") and into
private property. This land then needs to be obtained for the project to continue or the design
needs to be altered to avoid this expansion and property requirement. If there is an
encroachment onto private property from the implemented strategy, there will be a time /cost
commitment involved with securing easements from property owners.
Another concern of private driveways and their connections to the improved roadway is that in
many cases this may require altering the driveway to provide better connectivity. In short, there
are a set of similar issues that would need to be addressed to raise the roadway profiles to
address flooding that apply to impacts on private driveways.
Some of the primary constraining factors are identified in the list below and presented graphically
in Figure 12 - Conditions Potentially Impacting Roadway Design (Conceptual), which represents a
typical roadway in the Florida Keys.
P a g
2 0 1 J a n a- y 7 0 1 7
Monroe County Pilot Roads Project Twin lakes and Sands Communities
Final Report
Figure 12 - Conditions Potentially Impacting Roadway Design (Conceptual)
_ Ar.i,
r K a Adjacent Property
"�!C F Elevation
6 �# ` I R Driveway Access
'. : . '
Future Sea ... µ, �Ca
Level Rise -AP
Space for Drainage
s• .r '" 11/
Improvements
ter. f • k•yn. -� ._ }
{• • ROW Requirements
`"04/8/1/111/11/4 Electrical and
Water/Sewer
Elevation of Water Table Utilities
Water Quality Requirements Stormwater System
for Permitting , Maintenance Costs Including
Staff
The full list of factors which may impact design and implementation include:
• Conditions
— Future sea level rise impacts
— Current elevation of neighboring properties
— Current road conditions and elevations
— Accuracy of elevation data
• Environment
— Sensitive land
— Harm mitigation
— Water quality requirements and permits, including those specific to the County
• Space
— Horizontal right-of-way
— Horizontal space for drainage
— Elevation of water table in relation to road elevation
i .. r 1
Monroe County Pilot Roads Project - Twin lak a n d Sa Communities
Final Report
• Impact
— Private property access
— Future maintenance cost, including staff
It is important that these local conditions be addressed, in order for a project to be successful. In
the case of this Pilot Project, which only develops a conceptual design, the Team also
collaborated with the South Florida Water Management District ( "SFWMD "), Florida Department
of Environmental Protection, and the Florida Keys National Marine Sanctuary. The Team had
initial discussions with these agencies regarding stormwater drainage design from roadways from
this project. These conversations were key to bringing all stakeholders to the table and ensuring
their input during this very conceptual phase.
Fage 7 7 I Janua - y 7017
Monroe County Pilot Roads Project Twin lakes and Sands Communities
Final Report
4 Recommendations
Study Past
Events and
Determine
Flooding
Recurrence
Consider Sea
Level Rise
Estimates for
the County
Develop Identify Design
Engineering Alternatives
Response Responsefor
Strategies w/
Estimated Costs Communities
4.1 ESTABLISHING A BASELINE FOR DECISION - MAKING
Recently, the County has begun factoring sea level rise considerations into decisions related to
road improvement projects. The factors already being considered on a project -by- project basis
include tide levels at the location of the project, tide elevation seen on average or during the Fall
2015 King Tide event, and the projected sea level rise for a 2040 scenario. These efforts have
occurred in response to public comment and were driven primarily by the events of 2015.
While these changes have already been incrementally made, the County should adopt a more
comprehensive policy that takes into account site - specific conditions as warranted, given
resources available. From a policy perspective, while the County may decide upon a particular
level of projected sea level rise to drive design decisions, other considerations may prevent that
projection from being achieved such as the local conditions identified in the previous section.
Design alternatives should be based on a number of considerations, including those from policy,
data and engineering perspectives. These are fully outlined below:
• From a Policy Perspective
— The issue of sea level rise will be one with implications county -wide so the effort
to identify an appropriate design elevation in these two communities is important.
— Given the broader recognition of County needs and resources, the focus of the
County should be on delivering future flooding levels of service for more regular
conditions than only those conditions noted in 2015. This is why a future sea level
rise projection should be chosen to guide road design considerations as a primary
consideration rather than responding and designing to the Fall 2015 event.
— Use of scenarios should be tied to the useful life of a project per Policy 1502.1.1
of the Comprehensive Plan.' For that reason, the study team focused on the use
of 2040 sea level rise projections to reflect the 25 -year life of a road project.
3 Prior to incorporating a new project to the Capital Improvements Element, Monroe County shall assure that it is reviewed for
recommendations to increase resiliency and account for the impacts from climate change, including but not limited to, sea level
rise and storm surge. Monroe County shall evaluate financial expenditures to fund repairs, reconditioning of deteriorating
infrastructure and new infrastructure improvements within or proximate to vulnerable areas to manage public investments
appropriately. Monroe County shall focus on level of service standards, as one of the points of analysis, to assure that
infrastructure useful life and service expectations can be met in the face of climate change impacts.
Janua 1017 PaEP 7 3
Monroe County Pilot Roads Project Twin I okes a n d Sa Communities
Final Report
• From a Data Analysis Perspective
— An evaluation has been completed for impacts projected for each sea level rise
scenario and recurrence interval, which translates into a specific elevation for
segments of the identified roads in each community.
— Should the IPCC AR5 Median projection be used, a certain level of relief over an
extended period of time would be realized even if the high sea level rise rate were
to occur. The opposite is true, that if the high projection be used, the level of relief
may carry over to a future maintenance cycle or longer potential project life thus
resulting in overdesign of the project.
— Scenarios have also been compared to the Fall 2015 event to show the level of
relief anticipated both from future 2040 conditions as well as what was seen last
year.
• From an Engineering and Implementation Perspective:
— Designing to any scenario should raise the current roadway profile reducing the
level and duration of flooding, resulting in a passable roadway under most current
and future estimated conditions.
— Under - design and over - design considerations translate to fiscal performance
trade -offs that must be considered in the context of future risk for the County.
4.2 EXAMPLE DECISION- MAKING
As an example of the options available for design - two approaches to the level of sea level rise
can be considered given the uncertainties of future sea level rise values and whether the IPCC
AR5 Median or USACE High sea level rise projections are realized over time.
Approach #1 uses the IPCC AR5 Median sea level rise projection of the Compact, which allows for
targeting a future level of sea level rise, but also allows incremental improvements if projections
track the USACE High scenario. The risk is that the road project could be considered "under -
designed" and will show impacts before the estimated 2040 end of the life of the project (after
2030), but the road project could still provide some level of relief. The concept is that the base
material could be constructed to support additional pavement in the future to accommodate a
few additional inches of elevation, allowing for more flexible adaptation design based on what
real sea level rise impacts occur versus those projected to occur. Approximately 3 -4" of additional
pavement could be added on top of the installed pavement as an overlay to further raise the
profile of the road should actual sea level rise track the higher end of the 2040 range. This
incremental process is supported by the Compact's Unified Sea Level Rise Projection (2015).
4 The designer of a type of infrastructure that is easily replaced, has a short lifespan, is adaptable, and has limited
interdependencies with other infrastructure or services must weigh the potential benefit of designing for the upper blue line with
the additional costs. Should the designer opt for specifying the lower curve, she /he must consider the consequences of under -
designing for the potential likely sea level condition. Such consequences may include premature infrastructure failure.
Additionally, planning for adaptation should be initiated in the conceptual phase. A determination must be made on whether or
not threats can be addressed midlife cycle via incremental adaptation measures, such as raising the height of a sluice gate on a
drainage canal. [Unified Sea Level Rise Projection Southeast Florida, October, 2015 — page 121
Page 74 1 ianua - y 1017
Monroe County Pilot Roods Project Twin Cokes a Sands Communities
Final Report
Approach #2 would be to use the 2040 USACE High projection. Designing to 2040 USACE High
scenario might be considered a "no regrets" adaptation strategy if the higher levels of sea level
rise are realized. If future sea level rise impacts track more along the IPCC AR5 Median end of
the range, using the 2040 USACE High projection could result in overdesign and a higher upfront
cost to achieve a 2040 sea level rise condition. But if the road has already been elevated to a
higher level, this could reduce the cost of elevation and disruption to residents in a future
maintenance cycle.
Table 6 identifies how each of these approaches can be considered when combined with a road
design response. The table was assembled to highlight the differences between two elevation
options so that County officials can understand how different decisions can lead to various long-
term conditions, and potential costs.
J a n u a r y 7 0 1 7 P a g e 2 5
C)
cc
LL
h
v
u
c
i
O
a
c
O
z
w
c
O
Q.
O
0
c
c
v
D
V
-Q
a
QJ
a
i
O
O
2
-0
N
L
c
p
'
°
O
_ 3
'
o
�
>
t a c
v
>
>
N
w
=
c
C
Y
J
J
C
C
>
3
N
u
O
fC
W
E
, Vf
a
J +
o
v
0
0
'�
a�i
m oo
>
E c
�
W
W
a
c
.
o
a
c
m
e�i
a--1
_0
1 *
O
O E U
=
Q
N
N
N
N
--J
>.
e-1 p>
L
L
4-
L
4-
L
L
L
N W
N O
%6
ch
44
w
N
N
N
r
N
N
N
O m
V
s
C o
C
O
C
O
C
o
C
o
C
O
c£
O
£
v
v
v
a
N
C
C
C
C
C
C
O C.
x 0 d O
'
o
O
O
O
O
o
C N
a. ° v c
-r
�
cO
m
o
c
o
v
-Q
w
o
- a
c,
>.
4Z
�
v
v-C3
a;
0>
u
a
a
a
a
a
a
a
s 3 C.
t
3
`
c
a
-Q
V
n,
L
a
o
M
E
o
M
to
c
a
3
°
c
c
a
°
O
O
m
O
O
C.
+r
N
3
OJ
W
C
o
°'
o
N
DJ
°
�
_
O
2
°
w
o
o
a
QJ
N
O
O
v
°
a
�,
_
a
C3
4-,
a
i
a
a
Q)
a,
°
3
't3
v
,�
v
c
v
,n
c
N
s
*'
t
*'
O
O
a
co dA
c,
N
H
0
Qj
0
L
m
aj
>
m
-
t
tW
i
L
d1
41
II
4)
4J
N
O 'C
J
pG
L
>
m
'a
' a
O
M
C
M
L
0
0
a
C C
- Y
`
m
°'
0
3
3
0
-
U
v
-�
c
U
4
cc
in
t0
O
m
a �
G�
O
e� I w
_
c
o
cc
o
L
v
41
u
qj
o
V
v
M
'p
o
u
Y
m
m
+' C
f0
E
M C
E
M
N
M
N
Y
+�•�
-
Ql
41
t
+�+
t
m
E
'X O
D.
'X G!
00 .0
w
(
M
�
L E
O
O
L
O m
E
E
m
m
m=
?�
°c ?�
CL
a
a .__
M
u
O m
v m
>, O
C.
00
M
m
N>.
v
Y
N *'
' 2 0
II
20
II
II
2-1
II
II
C
2 to
C
2 to
r .=
Q .�
O `' L
Q C. H
°
_
c
=
a
O
t
M
�
O
to
E
°
v
Itil
a
d
H
N
N
N
CD
N
H
~
E
o
N
OQ
p
4-'
.
O
m
0 ++
i
L
y
L n
N
d O
4 C
aj
W
w U
U U W CZ U
-Q
a
QJ
a
i
O
O
2
ID
v
M
c
o
�
v
_a
3
u
O
�
o
v
�
v
�
W
a
c
.
o
0
a
�=
tm
v
i
=
c
a)
O
N
O
c
O
v
v
v
a
a
v
- t3
i
a,
v
c,
c
i
-r
�
cO
o
o
c
o
v
-Q
w
o
- a
c,
>.
4Z
�
v
v-C3
E
3
v
°
4.,
t
3
`
c
a
-Q
V
n,
L
a
o
M
E
o
o
a
a
3
-C3
a
3
Z
c
a
o
°'
o
Q)
o
°
v
-c
a
QJ
w
v
°
a
�,
_
a
C3
4-,
a
i
a
a
Q)
a,
°
3
't3
v
,�
v
a
v
Q6)
c,
Qj
01
3
t
G
aj
v
3
3
0
a
c
a
-�
`
a
a
v
v
U
v
-�
c
U
4
cc
EE
c
o
cc
o
v
v
u
qj
o
V
v
v
a
U
o
u
N
O
ID
v
M
Monroe C Pilot Roads Project - Twin lakes and Sands Communities
Final Report
4.3 STORMWATER MANAGEMENT DESIGN ALTERNATIVES AND
RECOMMENDATIONS
A single stormwater management system type was recommended for implementation at the two
pilot communities chosen for this project. There are, however, a number of stormwater
management options available county -wide as the County looks to implement a program of
roadway improvements. Those options have been outlined below for context. Selecting the
appropriate drainage infrastructure is dependent upon policy, data analysis, engineering and
most importantly local conditions. The available alternatives are explained in more detail below,
including notes on whether the strategy would be applicable in the two locations analyzed for
this study.
• Non - pressurized French drains (open or closed). Subsurface exfiltration -based system
that discharges to the groundwater table. A French drain itself consists of a horizontally
placed underground perforated 18" to 24" diameter pipe inside of a gravel and filter fabric
envelope. Typical depths range from 10 to 15 feet below ground surface.
— Engineering recommendation: Due to the reduced hydraulic head and low soil
permeability of the study areas, the implementation of this system is not practical.
The sea level rise makes it even less effective in these communities by further
reducing the hydraulic head.
• Pressurized French Drains (open or closed). Same as the first option, but with a pump or
lift station upstream to help move the water.
— Engineering recommendation: Same concerns as the first option noted above.
Also, additional construction and associated operation /maintenance cost of the
pump system makes this option less effective.
• Non- pressurized Drainage Wells. A drainage well consists of a vertically placed
underground 24" diameter casing pipe inside of a deeper well that discharges into the
Biscayne Aquifer. Typical well depths range from 100 to 150 feet below ground surface.
— Engineering recommendation: Due to the limited hydraulic head in the study
areas, the implementation of this system is not feasible. The sea level rise makes
it even less effective in these communities. Preliminary drainage calculations
indicate that the effective head in the wells would exceed the roadway elevations,
thereby surcharging the catch basins upstream.
• Pressurized Drainage Wells. Same as above, but with a pump or lift station upstream. In
addition, structures would be required to house the wells, which would need to be
between 4 to 5 feet above the lowest point on the road. Approximately 10 wells would
be necessary for Twin Lakes Community and 9 for the Sands Community, based on
preliminary estimates.
— Engineering recommendation:
■ A sound system and a possible option.
J a n u a r y 7 0 1 7 i P a g e 7 7
M o nr oe County Pilot Roads Project Twin Lakes and S ands Communities
Final Report
■ Ideal when hydraulic heads are a problem.
■ With careful construction, minimum pollution.
• Closed System (non - pressurized). Gravity -based system consisting of closed
underground piping and pollution abatement structures ( "PASs ") discharging into surface
waters.
— Engineering recommendation: Due to the limited hydraulic head and
configuration of the study areas, this alternative is not feasible. Adjacent
properties and mangroves along Shaw Drive prohibit the installation of outfall
pipes into surrounding surface waters.
• Pre - treated Closed System (pressurized). Same as above, but with a pump or lift station
upstream of the receiving water body along with a pre- treatment device, followed by a
valve unit, force main and energy dissipater structure, and outfall pipe.
— Engineering recommendation: Preferable and recommended system. The
installation of this system would require easements to access the adjacent
canal /bay on Father Tony Way through one of the residents' property in the Sands
Community. The system would require regular maintenance to operate
effectively.
The Team has recommended a pre- treated pressurized closed system as a strategy in the two
communities, primarily as a cost savings measure and as a way to reduce the above - ground
infrastructure requirements in the communities. The dialogue with environmental agencies with
regard to the system recommendations would need to continue once engineering design
recommendations are developed during the final design stage. The environmental agencies have
indicated that it is a preference to install injection wells where possible, but that a pre- treated
closed system may be possible and that a dialogue on sea level rise, water quality, and community
impacts would have to be held to finalize the strategy and obtain required permits.
4.4 PAVEMENT DESIGN AND INUNDATION
One factor to consider in low -lying areas like the pilot communities is that, even when raising the
road to said elevations, the lowest portions of the pavement will be exposed to moisture -vapor
and occasionally partially inundated from high groundwater table conditions.
It is known that excessive moisture within a pavement structure can adversely affect pavement
performance. Pavement structure refers to both the base material (often a compacted lime
rock material in Monroe County) and also the asphalt pavement layer which serves as the
roadway surface. When the moisture content in the pavement exceeds a stable amount, it may
become unstable or weaken. The detrimental effects of water on the structural integrity of
pavement can be technically described as follows:
• Water in the asphalt surface can lead to moisture damage, modulus reduction, and loss
of tensile strength.
P a g e 2 8 1 ! a n u a - y 7 0 1 7
Monroe County Pilot Roads Project Twin takes and Sands Communities
Final Report
• Added moisture in unbound aggregate bases and sub -bases is anticipated to result in a
loss of stiffness.
The effects of loss of stiffness and tensile strength, or "softening" in the pavement structure can
manifest into surface deformation and cracking. Over the life of the pavement cracks become
wider and more prominent, developing into channels through which moisture can flow. The
result is more moisture being allowed to enter the pavement structure with increasing pavement
age, which leads to accelerated development of moisture related distress and pavement
deterioration. The longer pavement is saturated, the more its useful life is reduced. This
translates to shorter than normal resurfacing or maintenance periods.
In the case of the pilot communities, where it may not be feasible or cost - effective to raise the
roads high enough to keep the pavement from becoming saturated or exposed to constant high
moisture levels, strategies for mitigating the effects of moisture include the following:
• Use materials and design features that are more resilient to the effects of moisture.
• Use drainage systems to quickly remove moisture that enters the pavement system
Unbound aggregate bases, like compacted limestone base, are more susceptible to loss of
stiffness than asphalt- treated or cement treated stabilized materials. The use of such materials
allows for more clearance from the groundwater table due to the fact that they have greater
strength per unit of thickness, and therefore can yield an overall thinner pavement
design. Geogrids provide another method for "reinforcing" or stabilizing the base layer when
exposed to high groundwater conditions. Another strategy is the use of permeable base material,
in conjunction with a geotextile separation layer and longitudinal edge drainage system, to
quickly remove water from the pavement, thereby reducing the amount of time it is saturated
and prolonging its life expectancy. Note that to ensure good performance, these drainage
systems require regular maintenance. In summary, before implementing these mitigation
strategies, each should be evaluated for cost - effectiveness when compared to traditional
pavements and life cycle costs.
4.5 FINAL TECHNICAL RECOMMENDATION
The previous sections outline efforts to develop a method for estimating future flood potential,
based on analysis of historical events. They also develop conceptual design and cost estimates
for the two pilot communities based on the four scenarios for design. This information was
generated as background to help formulate a recommended design response for the two
communities and identify howthose design recommendations may help to define County policies
moving forward.
A reality observed in the two pilot communities included significant flooding during the 2015
event, but also recurring flooding which occurs annually at different elevations. The flooding in
the Key Largo Twin Lakes Community was more extensive in terms of extent and duration than
that in the Sands Community during the 2015 event, which was in part due to an offshore storm
system pushing water into the neighborhood. The Big Pine Sands Community typically has higher
water and flood levels occur more regularly due to greater tidal influence in the area.
Recommendations for county wide road elevations must be adaptable to local conditions and
J a n u a r y 7 0 1 7 F a g e 2 9
Monroe County Pilot Roads Project Twin I okes and Sands Communities
Final Report
also reflective of the long term tidal record. The intent of this effort was to develop a method
that was specific to the full extent of potential annual tidal flood potential, not only one event
which may have a limited chance of recurring. The County recognizes that representatives in
these two pilot communities have requested a response to their problem, so the final
recommendations outlined below are mindful of those concerns and in each case identify
increased roadway elevations to address what has been observed in these communities.
Design Recommendation
The recommended design has been developed to address the two primary concerns of this
project to accomplish the following:
• Improve conditions related to annual tidal flooding observed in the two pilot
communities, and
• Incorporate projected sea level rise levels expected by 2040as the typical County road
lasts about 25 years. Develop target design road recommendations to reflect these goals
through the following:
— Identify a roadway elevation where up to seven days annually of tidal flooding
would be expected by 2040 — identified through an analysis of tidal conditions
over a past 20 -year period of record.
— In developing this calculation, apply the IPCC AR5 Median sea level rise projection
of the Compact.
To accomplish the above design features, the recommendation is that the project roads in the
Twin Lakes Community (Key Largo) be raised to approximately 5" of elevation NAVD88 (4.4 inches
as noted in technical material) to provide flooding relief, and extend the life of the road to 2040.
In the Sands Community (Big Pine), the recommendation is to raise the roadway elevation to
approximately 11" of elevation NAVD88 (10.3 inches as noted in technical material) based on a
similar assessment.
To develop these design recommendations, the following levels were used:
1. Value of the calculated 2015 MHHW value at each location.
2. The estimated water level where, on average, seven days of annual flooding is likely to
occur in each location. Note that "on average" indicates there may be little to no flooding
some years and more than seven days flooding in other years.
3. The addition of 5.4" of sea level rise from 2015 to 2040, based on the IPCC AR5 Median
sea level rise identified in the Compact's Unified Sea Level Rise Projection for Southeast
Florida (2015).
The full list of steps in the Methodology can be found at Appendix 2. Notable is the fact that each
recommendation (5" for the Twin Lakes Community in Key Largo and 11" for the Sands
Community in Big Pine) is very close to the range of the 4 scenarios evaluated in the project (first
identified in Section 3.3 as 6 ", 12 ", 18" and 28 "). When accounting for sea level rise and a point
at which flooding does not exceed 7 days annually, the data resulting from evaluating the 6" and
P a g e 3 0 1 J a n c a r y 7 0 1 7
Monroe County Pilot Roods Project Twin lakes and Sonds Communities
Final Report
12" scenarios in terms of cost, stormwater features and length of roadway to be elevated show
a conceptual picture of what elevating to 5" and 11" will actually require. In summary:
►vore: 3cenano Lons►aerea means the scenario evaluated in this analysis that is the closest to the
recommendation when applying the Methodology in Appendix 2.
Additional Considerations for Design Guidance
These recommendations were developed to address typical and anticipated tidal flooding in the
two pilot communities. In both communities, the intent was to identify an ultimate
recommended roadway elevation that would address current conditions and long -term changing
flooding patterns expected to worsen as sea level rises. A few important additional
considerations include:
• The design does not need to be considered a one -time decision. The road could be
constructed in the near term in such a way that the base material installed could support
later additional material, while modifications would also be possible to also maintain the
viability of the recommended stormwater system. This approach allows for flexible design
implementation, should a higher sea level rise rate be realized within the project life time.
This incremental process is supported by the Compact's Unified Sea Level Rise Projection
(2015).
• Rising sea levels will result in a comparable rise in groundwater levels in Monroe County.
This reality means that the base materials supporting the roadways constructed in the
two pilot communities would likely be inundated regularly as tide cycles shift, or
continuously if base material is installed below the mean sea level water level. The
recommendation is that the County conduct additional research to determine how
optional available base materials may help to reduce erosion in these areas and
contribute to long -term roadway viability. This research will need to address construction
materials, long -term maintenance costs and the benefits of additional roadway elevation
as a method to maintain pavement quality long -term. The results of this research may
alter the elevation recommendations identified above.
J a n u a- y : 0 1 7 P a g e 3 1
Scenario Considered
Elevation Length
Conceptual Cost
Recommendation for Twin Lakes
6"
.3 Miles
$0.92 Million
Community in Key Largo of 5"
Recommendation for Sands
12"
.34 Miles
$2.63 Million
Community in Big Pine of 11"
►vore: 3cenano Lons►aerea means the scenario evaluated in this analysis that is the closest to the
recommendation when applying the Methodology in Appendix 2.
Additional Considerations for Design Guidance
These recommendations were developed to address typical and anticipated tidal flooding in the
two pilot communities. In both communities, the intent was to identify an ultimate
recommended roadway elevation that would address current conditions and long -term changing
flooding patterns expected to worsen as sea level rises. A few important additional
considerations include:
• The design does not need to be considered a one -time decision. The road could be
constructed in the near term in such a way that the base material installed could support
later additional material, while modifications would also be possible to also maintain the
viability of the recommended stormwater system. This approach allows for flexible design
implementation, should a higher sea level rise rate be realized within the project life time.
This incremental process is supported by the Compact's Unified Sea Level Rise Projection
(2015).
• Rising sea levels will result in a comparable rise in groundwater levels in Monroe County.
This reality means that the base materials supporting the roadways constructed in the
two pilot communities would likely be inundated regularly as tide cycles shift, or
continuously if base material is installed below the mean sea level water level. The
recommendation is that the County conduct additional research to determine how
optional available base materials may help to reduce erosion in these areas and
contribute to long -term roadway viability. This research will need to address construction
materials, long -term maintenance costs and the benefits of additional roadway elevation
as a method to maintain pavement quality long -term. The results of this research may
alter the elevation recommendations identified above.
J a n u a- y : 0 1 7 P a g e 3 1
Monroe County Pilot Roads Project Twin Jokes and Sonds Communities
Final Report
5 Part II: Legal and Policy Analysis
5.1 LEGAL ANALYSIS /BACKGROUND
As the impacts from sea level rise become more prevalent within Monroe County, a complete
understanding of the County's responsibilities and duties with regard to specific infrastructure
will become critical. It will become increasingly necessary to understand the County's obligations
for each type of service provided, as well as the County's rights and obligations in reducing levels
of service in response to sea level rise.
Local Government's Responsibility for Providing Services
Generally, local governments do not have a legal duty to provide particular services. Instead, the
powers of a local government are defined by what they are permitted to do, rather than what
they are compelled to do.'
With regard to services, Florida courts distinguish between "upgrading" and "maintenance" of
infrastructure. The Florida Supreme Court has held that "the decision to upgrade" infrastructure
is considered a "planning -level function, to which absolute immunity applies ".' In contrast, this
same Court has held that failing to "maintain" infrastructure is an "operational" activity that
exposes the government to potential liability.' These decisions solidify the distinction that the
government has immunity for planning decisions (which includes upgrading infrastructure) but
not operational decisions (like maintenance), which require a duty to act with reasonable care to
avoid harm to others.
However, the difference between maintenance and upgrading of infrastructure remains grey
under Florida law in the context of a local government's duty to respond to changed
circumstances affecting services — like increased flooding due to sea level rise.' Courts in other
states have addressed this issue and concluded that there is no obligation to "upgrade" when the
upgrade is a discretionary, planning -level decision rather than an operational function.'
s See Ecological Dev., Inc. v. Walton Cnty., 558 So. 2d 1069, 1071 (Fla. 1st DCA 1990) ( "A county is not obligated ... to perform or provide for any
particular construction or maintenance, except as it voluntarily assumes to do. "); Dep't of Transp. v. Neilson, 419 So. 2d 1071, 1077 (Fla. 1982)
( "The decision to build or change a road, and all determinations inherent in such a decision, are of the judgmental, planning -level type. To hold
otherwise would ... supplant the wisdom of the judicial branch for that of the governmental entities whose job it is to determine, fund, and
supervise necessary road construction and improvements, thereby violating the separation of powers doctrine. "); Gargano v. Lee Cnty. Bd. of
Cnty. Commis, 921 So. 2d 661, 667 (Fla. 2d DCA 2006) ( "It is well established that decisions concerning the maintenance of and need to construct
roadways, bridges, and other similar services are political questions outside the purview of the courts. "); Trianon Park Condo. Assn v. City of
Hialeah, 468 So. 2d 912, 920 (Fla. 1985) ( "A governmental entity's decision not to build or modernize a particular improvement is a discretionary
judgment function with which we have held that the courts cannot interfere. ").
6 See Dep't of Transp. v. Konney, 587 So. 2d 1292, 1296 (Fla. 1991) (holding that the decision of a government to upgrade an intersection was a
planning level decision the government had immunity from).
' See Neilson, 419 So. 2d at 1073 (affirming the Commercial Carrier holding that "the failure to properly maintain existing traffic control devices
and existing roads may also be the basis of suit against a government entity").
8 Thomas Ruppert and Carly Grimm, Drowning in Place: Local Government Costs and Liabilities for Flooding Due to Sea -Level Rise, Fla. Bar
Journal. Vol. 87, No. 9 (Nov. 2013), available at:
htto:// www. floridabar .oro /divcom /in /iniournal01 nsf/ 8c9fl30l2b96736985256aa900624829/ dlcd8a7e6519800885257cl200482c39 !OpenDoc
ument
(Florida case law has not directly ruled on the issue of whether changed circumstances that cause increased flooding despite a stormwater system
still in its proper design condition results in liability for a failure to "maintain" or if changed circumstances leading to flooding indicates that a
local government has discretion as to whether to "upgrade" the system).
' Id. (citing Alden v. Smith Cnty., 679 N.E. 2d 36, 38 (Ohio Ct. App. 1996); Colemn v. Portage Cnty. Eng'r, 975 N.E. 2d 952, 960).
P E g e 3 7 l i J a u a r y 7 0 1 7
Monroe County Pilot Roads Project Twin lakes and Sands Commurities
Final Report
Local Government's Responsibility to Provide Drainage
In Florida, local governments have no general duty to provide drainage. All local governments
are permitted by statute to engage in the construction and management of drainage systems,
but these are discretionary duties on the part of the local government." However, once a local
government does provide protection from flood damage through the construction of a storm
sewer pump or similar system, it assumes the duty to do so with reasonable care. Stated
another way, when a local government provides this type of infrastructure, it "thereby assume[s]
the duty to maintain and operate the system so that it [will] properly drain off expected excess
water and prevent flooding. "
Local Government's Responsibility to Provide Drainage for Roads
Local governments do have a duty to reasonably maintain existing roads and traffic controls.
However, this duty applies only to a road "as it exists" and "does not contemplate maintenance
as the term may sometimes be used to indicate obsolescence and the need to upgrade a road. ""
The duty to reasonably maintain roadways does not obligate the local government to upgrade a
road through measures like road widening or changing the means of traffic control. These
measures have been deemed discretionary functions and cannot be compelled by the courts.
Whether a local government has a duty to upgrade existing drainage systems to effectively drain
greater volumes of stormwater or address flooding from sea level rise or extreme rain events will
depend upon whether courts classify this action as a discretionary, planning -level or a
nondiscretionary, operational- and maintenance -level function. Since the failure of drainage
systems to function as effectively due to sea level rise represents a changed situation that would
require a redesign of the system to provide the same level of service previously provided, it would
seem more logical to classify this as an "upgrade" rather than "maintenance. " If that is the case,
a local government's decision not to upgrade such a system would be covered by sovereign
immunity, insulating the local government from flooding damage claims by those impacted if a
drainage system is not upgraded.
10 Supra, note 8.
11 Id.; See, e.g., Fla. Stat. § 170.01(1)(a) & (b) (2016) ( "Any municipality of this state may, by its governing authority ... provide for the ... guttering,
and draining of streets, boulevards, and alleys...[o]rder the construction, reconstruction, repair, renovation, excavation, grading, stabilization,
and upgrading of greenbelts, swales, culverts, sanitary sewers, storm sewers, outfalls, canals, primary, secondary, and tertiary drains, water
bodies, marshlands, and natural areas, all or part of a comprehensive stormwater management system, including the necessary appurtenances
and structures thereto and including, but not limited to, dams, weirs, and pumps. "); Fla. Stat. § 403.0893 (2016) (granting local governments
authority for certain mechanisms to fund stormwater management).
12 Id. (citing Slemp v. City of N. Miami, 545 So. 2d 256, 258 (Fla. 1989)).
13 Id.; See also Sw. Fla. Water Mgmt. Dist. v. Nanz, 642 So. 2d 1084, 1086 (Fla. 1994) ( "Having assumed control of this drainage system and
undertaken to operate and maintain said drainage system, [d]efendants, and each of them, had a duty and obligation to prudently operate,
control, maintain, and manage said system so that it would work properly and drain off excess waters so as not to cause flooding in the area.
Defendants owed said duties and obligations to your [p)laintiffs, residents and /or owners of homes and real property serviced by the drainage
system. "); Trianon Park Condo. Assn, Inc., 468 So. 2d 912; Collazos v. City of W. Miami, 683 So. 2d 1161 (Fla. 3d DCA 1996).
14 Id. (citing Neilson, 419 So. 2d at 1078).
15 Id.
16 Id. (citing Konney, 587 So. 2d at 1294).
17 Id.
1s Id.
19 Id.
20 Id.
Ja❑uary 7017 Page 2 3
Monroe County Pilot Roads Project Twin lakes and Sands Communities
Final Report
Services Reduced or Compromised
There may also be instances where the County needs to reduce transportation infrastructure
services in response to flooding or sea level rise. Florida law provides specific procedures and
requirements for counties to use in closing or abandoning roads. Additionally, the recent Jordan
v. St. Johns County decision involved the effects of erosion on St. Johns County's ability to
maintain a county road. In this case, St. Johns County did not to maintain Old A1A because of
the frequency of washout and the economic burden on the County for a limited number of
residents using the road. The opinion specifically noted that the County's procedural failure to
formally abandon the road in accordance with the statute helped support the residents' liability
claims. Should Monroe County decide to stop maintaining perpetually flooded roadways in the
future, a key component is that the statutory abandonment process should be utilized.
Sea Level Rise Policy in Comprehensive Plans
In 2015, Florida passed a law entitled "An Act Relating to the Peril of Flood. 1123 These new
provisions now require that coastal management elements of Comprehensive Plans include a
"redevelopment component that outlines the principles that must be used to eliminate
inappropriate and unsafe development in the coastal areas when opportunities arise. " While
the redevelopment concept in the coastal management element itself is not new, what is
required to be addressed in the element has been enhanced. The new full requirements include:
• Development and redevelopment principles, strategies, and engineering solutions that
reduce the flood risk in coastal areas which results from high -tide events, storm surge,
flash floods, stormwater runoff, and the related impacts of sea level rise.
• Encouraging the use of best practices development and redevelopment principles,
strategies, and engineering solutions that will result in the removal of coastal real
property from flood zone designations established by FEMA.
• Identifying site development techniques and best practices that may reduce losses due
to flooding and claims made under flood insurance policies issued in this state.
• Being consistent with, or more stringent than, the flood- resistant construction
requirements in the Florida Building Code and applicable flood plain management
regulations set forth in 44 C.F.R. part 60.
• Requiring that any construction activities seaward of the coastal construction control
lines established pursuant to Section 161.053, F.S. be consistent with Chapter 161, F.S.
• Encouraging local governments to participate in the National Flood Insurance Program
Community Rating System administered by FEMA to achieve flood insurance premium
discounts for their residents."
21 See Fla. Stat. §§ 316.006, 336.09, 336.10, 336.12, 336.125 (2016).
22 Jordan v. St. Johns Cnty., 63 So. 3d 835 (Fla. 5 1 h DCA 2011).
23 Laws of Florida, 2015 -69.
24 Laws of Florida, 2015 -69, § 1, codified at Fla. Stat. § 163.3178(2)(f) (2016).
25 Erin L. Deady, Esq., AICP, LEED AP and Thomas Ruppert, Esq., The Link Between Future Flood Risk and Comprehensive Planning, 2 ELULS Reporter
7 -8 (Sept. 2015); available at: eluls.org /wo content /uploads/ 2015 /06 /September- 2015 - Edition -Final pdf
F a g e 3 4 1 J a n u a r y 7 0 1 7
Monroe County Pilot Roods Project Twin lakes and Sonds Communities
Final Report
Local governments appear to have broad discretion as to how they comply with this new
mandate. And corollary to that, the law does not specify a date by which local governments must
comply. That said, Section 163.3191(1), F.S. still requires local governments to evaluate their
plans at least once every seven years to determine if amendments are necessary to reflect
relevant changes in state law and a local government also has the authority pursuant to Section
163.3191(2), F.S. to make a determination that amendments are necessary sooner than that 7-
year requirement. 26 With that, Monroe County will have some level of discretion in terms of
compliance with these new requirements, but the concepts contained within this Report related
to infrastructure planning and design for roads are conceivably a compliance strategy.
Additionally, all the work the County is doing related to achieving a favorable score in the
Community Rating System will also lend itself to compliance with these new requirements.
Local Government's Liability with Regard to Service Delivery
The two most prominent liabilities facing the County with regard to service delivery are those of
sovereign immunity and potential takings claims.
a. Sovereign Immunity
Florida waived sovereign immunity in tort actions in 1973 with its Torts Claims Act '27
opening the door for private citizens to sue local governments over flooding damage.
However, tort claims involving government infrastructure may still be subject to
sovereign immunity despite the statutory waiver .21 The Florida Supreme Court has held
that despite the Act, certain "discretionary" government functions remain immune from
tort liability because these "planning" level functions may not be subject to scrutiny by
judge or jury as to the wisdom of their performance . These planning level decisions are
contrasted from those operational functions as discussed above.
b. Takings Claims
There is also potential liability for local governments related to service delivery through
private takings claims. There are two types of takings: 1) per se and 2) as applied takings.
Per se takings amount to a taking of all viable economic use of the property. 31 As applied
takings claims require a case -by -case factual analysis of the degree of interference with
property use.sz
To support a claim for inverse condemnation, flooding must be caused by government action
that results in "an actual, permanent invasion of the land, amounting to an appropriation of and
not merely an injury, to the property. 1133 The "permanent" invasion element of a taking is
satisfied, according to Florida courts, where periodic flooding occurs or is expected to recur, that
26 Id.
2' Fla. Stat. §768.28 (2016).
21 Supra, note 8.
29 Id.
31 Id. (citing Commercial Carrier Corp. v. Indian River Cnty., 371 So. 2d 1010, 1022 (Fla. 1979) and Konney, 587 So. 2d at 1294).
31 Lucas v. S. Carolina Coastal Council, 505 U.S. 3003 (1992).
32 Lost Tree Village v. City of Vero Beach, 838 So. 2d 561, 570 (Fla. 4 DCA 2002).
33 Supra, note 8 (citing S. Fla. Water Mgmt. Dist. v. Basore of Fla., Inc., 723 So. 2d 287, 288 (Fla. 4th DCA 1998)).
J a n Ua - y 01 7 P g 35
Monroe County Pilot Roads Project Twin lakes and Sands Communities
Final Report
deprives the property owner of all reasonable use of their land. Recently, the U.S. Supreme
Court held that periodic flooding, even if only temporary, may result in a compensable takings
claim for damage to property if it's also caused by governmental action [emphasis on the
causation by governmental action]. This suggests that government action causing even periodic
flooding on a temporary basis may be a taking, depending on the specific facts at issue. But note
the distinction is based on the actual governmental action causing the flooding for instance
where the government constructs a building that causes flooding to an adjacent property owner.
The inaction of government has not historically been sufficient to support a claim for inverse
condemnation, but this is an important concept to consider.
The Jordan case calls that general principle of inaction into question unfortunately. 37 Landowners
sued St. Johns County alleging that the County failed to reasonably maintain a County -owned
road known as "Old AM" to such an extent that the County deprived the landowners of access
to their land, resulting in a taking of property. As briefly noted above, there was a dispute among
several private property owners challenging St. Johns County over their legal responsibility to
maintain Old A1A, a coastal road inundated by storms and hurricanes. In 1979, the State deeded
Old A1A to the County. By 2005, the County enacted a temporary residential building
moratorium for properties along the roadway segment at issue (approximately 60 in total).
In response to the County's actions, a complaint was filed in 2005 against St. Johns County
claiming generally that the County had deprived these landowners of access to their land. A total
of five claims were raised against the County, including: 1) that the County had a duty to provide
emergency services; 2) that the County had a duty to restore and perpetually maintain Old A1A
to ensure the property owners' access; 3) an injunction was needed requiring the County to
perpetually maintain Old A1A to ensure access; 4) inverse condemnation due to the deteriorated
road /lack of access; and 5) inverse condemnation due to the temporary building moratorium.
As a low -lying coastal road, Old A1A is subjected to continuous damage from natural forces,
including storms and erosion and although not mentioned, even sea level rise . The County
argued that the only feasible way to protect the road from the "ravages of the ocean" was to
expend more than $13 million to elevate the height of the road by placing large amounts of sand
along its entire length from the right -of -way down to the mean high -water mark. The County
further argued that it would have to spend an additional $5 -8 million every 3 -5 years to maintain
that protection. According to the County, it could not spend these sums because they
34 Id. (citing Elliott v. Hernando Cnty., 281 So. 2d 395, 396 (Fla. 2d DCA 1973) (holding that plaintiff's property rights had been sufficiently infringed
to demonstrate a taking under the Florida Constitution when the government diverted the natural flow of rain waters to appellants' real property
and subsequently rendered the property unusable and unsanitary. Such flooding was considered "permanent" in that rain is a condition that is
reasonably expected to continually reoccur in the future)).
35 Id. (citing Ark. Game & Fish Comm'n v. United States, 133 S. Ct. 511 (2012)).
36 Id. (citing Grim Broadband Commc'ns, Inc. v. United States, 79 Fed. Cl. 320, 324 (2007) ( "A necessary component of any takings claim is that
the [g]overnment actually took property, whether by physical invasion or regulatory action.... ")). See also Robert Meltz, Substantive Takings Law:
A Primer, a paper presented at the 12th Annual CLE Conference on Litigating Regulatory Takings and Other Legal Challenges to Land Use and
Environmental Regulations at 14 -15 (Nov. 2009), available at htto:// www. viel. org/ docs/Takings %20Conference /Meltz Vermont confY20—
%20takings orimer.odf
37 Jordon, 63 So. 3d at 839.
38 Id.
39 Supra, note 8.
40 Id.
P a g e 3 6 1 J a n u a r y 7 0 1 7
Monroe County Pilot Roads Project Twin lakes and Sands Communities
Final Report
represented more than the entire County budget for repair and maintenance of the County's 800
miles of roads.
At the lower level, the trial court entered final summary judgment in the County's favor on all
counts. On appeal though, the Fifth District Court of Appeal opined that the County had a duty
to "reasonably maintain" and repair Old A1A in such a way as to result in "meaningful access . "
The case was remanded to determine whether the County had fulfilled its duty. More
significantly, however, the court held that governmental inaction — in the face of an affirmative
duty to act — can support a claim for inverse condemnation .1141 For the first time in Florida, this
case established a precedent that government inaction may be grounds for a plaintiff to bring a
constitutional takings claim if the government had a duty to act. 44 In December 2011, the Florida
Supreme Court declined review in this case.
The case ultimately settled whereby the County and property owners came to agreement on
levels of service for the road in the future, recognizing the environmental challenges impacting
the quality of the road in the future. As part of the settlement, the following were agreed to:
• County agreed to use "good faith" efforts to maintain Old A1A in "As Is" condition;
• County agreed to use "timely and good faith efforts" to keep access open;
• County agreed to include the existing paved portion of Old A1A in the pavement
management schedule and repave it as needed;
• County agreed to resurface a 0.3 -mile portion of Old A1A to create a connection with New
A1A;
• The County agreed to remove diminished road access as an impediment to obtaining
building permits;
• Property owners agreed to give the County notice and an opportunity to buy properties
along this roadway before selling to others;
• The County agreed to repeal the requirement that prospective home builders sign "hold
harmless" agreements to get building permits;
• Property owners agreed to grant easements to restore access to parcels outside of the
existing paved area;
• Agreed to allow transit over County -owned parcels to facilitate access to parcels outside
of the existing paved area;
• Agreed to consider recommendations of the Summer Haven Municipal Services Taxing
Unit ( "MSTU ") regarding the use of MSTU funds; and
• County agreed to pay $75,000 to partially reimburse Plaintiff- Owners' costs.
41 Jordan, 63 So. 3d at 837.
41 Id. at 839.
43 Id
44 Supra, note 8.
" Exhibit A: Settlement Agreement and Release, Case. No. 05 -CA -0694.
J a n u a r y 7 0 1 7 P a g e 3 7
Monroe County Pilot Roods Project Twin lakes and Sonds Communities
Final Report
5.2 CASE STUDIES
As sea level rises and flooding increases in Florida, local governments are beginning to make
policy decisions in response. Two case studies, St. Johns County and Miami Beach, are
particularly useful in illustrating how Florida governments are responding through the use of pilot
projects to develop preliminary design criteria. Additionally, the SFWMD is also starting to
address these issues.
St. Johns County- Natural Forces Ordinance
As a result of the Jordan case discussed above, St. Johns County adopted an ordinance in 2012
to specifically address "natural forces degradation" and damage to public roads and streets and
other improved public rights -of -way used for travel and recreation. In essence, the ordinance
creates a "Design Exception" to allow the County to deviate from the minimum standards
mandated by the Florida Department of Transportation's Greenbook. The ordinance establishes
design criteria and standards for existing roads in areas designated as "environmentally -
challenging locations" and defines meaningful access for the users of such roads.
Environmentally - challenging locations are defined, among other things, as "locations where
typical road design criteria and standards are infeasible due to the economic implications of
naturally occurring conditions. " Meaningful access is defined as "the ability to use some type
of commercially available land vehicle on a road or portion of a road owned and maintained by
the County for access to private property. For property along formerly opened State or County
roads, or portions thereof, meaningful access shall include access to such property by way of
necessity by law or in fact. "
The following design criteria were adopted by St. Johns County in this ordinance:
• Design criteria listed serve as an approved Design Exception to the uniform minimum
standards for the design, construction, maintenance and operation of public roads
pursuant to Section B, Chapter 14 of the Florida Greenbook;
• Due to forces of nature and environmental conditions, access to property by roads in
environmentally - challenging locations may be limited. The Commission may then
designate such road as being located in an environmentally - challenging location;
• For those designated as located in environmentally - challenging locations, the minimum
standards of maintenance shall differ from the County's general maintenance standards;
• Roads in environmentally - challenging locations may experience conditions that
necessitate that the County's design criteria be altered to the point that the following
may be present in providing meaningful access:
— Unpaved surfaces and sub - surfaces composed of muck, sand, clay or organic
material.
— Sub - standard lane widths, single lanes and varying maintained widths.
ae See St. Johns County, Fla., Ordinance 2012 -35 (effective Dec. 11, 2012).
47 Id
as Id.
P a g e 3 8 1 a n 4 a y 7 0 1 7
Monroe County Pilot Roads Project Twin lakes and Sands Communities
Final Report
— Vehicle type, size, and weight limitations.
— Periods of time when the roads may be submerged, buried by soil, covered by
sand or blocked by vegetative debris.
— No assurance that emergency vehicles can use or routinely use the road for access.
— Paved surfaces with intermittent pavement, potholes, cracks, loose material.
— Other conditions that cause the roads to be in substandard condition.
• Property owners with existing improvements that are accessed by roads that are located
in environmentally - challenging locations may encounter access issues.
• Access to private property served by existing County -owned or maintained roads in these
locations may be limited by naturally occurring conditions beyond the reasonable control
of the County. Resulting circumstances may include:
— Roadway conditions require the use of a four -wheel drive vehicle for passage.
— Periods of time before roadway repair will be accomplished when vehicular access
is not possible or is more limited than usual.
— Extended periods when access and the roadway are impassable to vehicles.
— Instances when roadway repair cannot be accomplished without permits issued
by state or federal agencies for necessary impacts to a protected resource.
• Any owner in a designated area who rents property for more than fourteen days in a
single calendar year is deemed to have meaningful access regardless of roadway
condition.
• Except by the Commission, the County has no affirmative duty to construct or permit
construction of new or extended roads in these designated areas.
• County has no obligation to improve any portion of a County -owned and maintained road
in a designated area adjacent to private property who purchases property after the
ordinance existed or after the County designated the location.
• Nothing in the ordinance prohibits private property owners from petitioning the
Commissioners for a vacation of the road or for the establishment of a Municipal Services
Benefit Unit or Municipal Services Taxing Unit.
City of Miami Beach- land Development Regulations
The City of Miami Beach has experienced significant tidal flooding in recent years. The City is
currently moving toward the development of design criteria to incorporate into its land
development regulations of citywide road design, but has not yet done so. Although it is not
yet incorporating sea level rise considerations into its building code, the City has explicitly
49 Id.
so Conversation with Bruce Mowry, City Engineer, City of Miami Beach on or around November 18, 2016.
J a n u a r y 2 0 1 7 P 2 g e 3
Monroe County Pilot Roads Project Twin lakes and Sands Communities
Final Report
accounted for "sea level change" in its Stormwater Management Master Plan ( "SWMMP "). The
City's new SWMMP accounts for sea level rise, makes recommendations for 20 -year capital
improvements, provides flexibility for various rates of sea level rise, and provides drainage
analyses using technical modeling. In its 20 -year capital improvement program, the SWMMP
accounts for sea level change over a 20 -year planning horizon for stormwater infrastructure and
50 -year horizon for seawall heights.sz
In addition to sea level rise generally, the City is also responding to impacts from exceptionally
high tides, or "King tides. " 53 These King tides cause the City's gravity flow stormwater drainage
infrastructure to become ineffective, which results in road flooding . 5 ' The City has addressed the
problem in the short-term by installing check valves, which only allow outflow, at points where
stormwater pipes discharge into Biscayne Bay, and pumps to give the stormwater sufficient
pressure to overcome the increased inflow pressure associated with the high tides .55 For the
longer term solution, the City has also raised the stormwater infrastructure design sea level
considerations by two feet in the new SWMMP, to both account for the King tides and begin to
address future sea level rise. 56
The City is also implementing requirements on buildings to prepare for rising water. Because sea
level rise will eventually require the City to raise its streets and sidewalks, and because all
structures within the City are within a floodplain, the City is currently requiring new buildings to
include false fronts. This allows the building's ground floor to be above street level, yet still
accessible to persons with disabilities, and already capable of accommodating a higher street
Ievel.
Much of the City's work in addressing sea level rise through road design (or elevated re- design)
has been the result of two pilot projects: 1) Sunset Harbour Neighborhood Improvement Project 59
and 2) West Avenue Neighborhood Improvement Project .61 Sunset Harbour is an improvement
project that includes both infrastructure improvements and above - ground improvements.
Water mains and service, water meters, fire hydrants, sanitary sewer lines and manholes, and
the existing stormwater drainage system are all included in the preliminary infrastructure
improvements. Raising and reconstructing roadways and leveling private property driveways are
the sea level rise related above - ground improvements to be implemented through this project.
The West Avenue pilot project includes the installation of a new stormwater drainage system
with pump stations and raising the elevation of the roadway to minimize street flooding, along
52 Lenhers, M. et al., Planning for Sea -Level Rise: A Guide for Managers, Owners and Regulators of Water- Dependent Infrastructure, available at:
httns: / /www.law.ufledu/ adf /academics/ centers - clinics/ clinics / conservation /resources /final- deliverable 2b2 guidance document on slr and
water - dependent- infrastructure adf (last accessed Nov. 28, 2016).
52 Id.
sa Id.
sa Id.
ss Id.
56 Id.
57 Id.
sa Id.
59 See Sunset Harbour Neighborhood Improvements website, available at: http://www.mbplannedprogress com/proiects/neiahborhood-
improvements /middle beach / sunset - harbour - neighborhood - improvements
eo See West Avenue Neighborhood Improvement Project website, available at: http / /www mbplannedprogress com /aroiectslneighborhood
improvements/ south - beach / west - avenue - neighborhood- improvement - project
P a g e 1 0 1 J a n u a r y 7 0 1 7
Monroe County Pilot Roads Project Twin lakes and Sands Communities
Final Report
with matching the new roadway elevation to existing driveways. These improvements were
projected to be completed by Fall 2016.
Through these two pilot projects, the City has implemented — through resolution 61 and its
SWMMP — two specific design criteria addressing sea level rise. First, the City has adopted a 3.7'
NAVD crown of the road height. Second, the City has required that no inlet on a street shall be
less than 2.7' NAVD (based on drainage). The City also recently passed Ordinance 2016 -4010
defining crown of the road, future crown of the road, and establishing minimum and maximum
yard elevation requirements.
In addition, the City has also changed its regulations related to base flood elevation for residential
property, with regulations for commercial properties likely forthcoming. According to Bruce
Mowry, the City's Engineer, the City may also be mandating adaptive architecture in the future
to more easily accommodate building modification in response to sea level rise. Though the City
of Miami Beach has not yet adopted a comprehensive set of citywide criteria (for road design or
sea level rise generally), they continue to make policy and regulatory decisions in direct response
to sea level rise.
South Florida Water Management District Flood Control Structures
The SFWMD has developed a Flood Protection Level of Service ( "LOS ") program designed to
identify and prioritize long -term infrastructure needs. Level of Service projects provide a process
to establish flood protection thresholds for each basin within the SFWMD and while specific to
flood control structures, the idea of establishing such levels of service is pertinent. The flood
protection thresholds established are then used to initiate retrofits or other adaptation efforts in
the capital planning process. Of note, the thresholds are basin specific based on site - specific
assessments, and are not uniform everywhere. Adaptation efforts are coordinated with the
District's annual structure maintenance program.
As part of this program, the District uses its Conceptual Adaptive Resilience Model to establish
the sea level at which existing infrastructure no longer provides flood protection. Based on the
amount of time required to rebuild, conditions are established to trigger replacement of
particular infrastructure. The SFWMD then monitors conditions and initiates an adaptive
strategy once a given condition is realized.
The SFWMD is currently implementing the Flood Protection Level of Service program through
several projects, including:
• C -4 Basin LOS project — to determine the existing and future (using three sea level rise
scenarios) flood protection level of service for this basin to prioritize flood protection
issues and initiate basin - specific solutions. The project was slated to be completed by the
end of FY 2015 -16;
• C -7, C -8 and C -9 Basins LOS projects — to determine the existing and future (using three
sea level rise scenarios) flood protection level of service for these basins to develop flood
61 See City of Miami Beach, Fla., Resolution 2016 -29366 (Apr. 13, 2016) and City of Miami Beach, Fla. Resolution 2014 -28499 (Feb. 12, 2014).
62 See City of Miami Beach, Fla., Ordinance 2016 -4010 (effective Jun. 8, 2016).
January 2017 Page 4 1
Monroe County Pilot Roads Project Twin I okes and Sonds Communities
Final Report
protection strategies with Miami -Dade County and incorporate into the Local Mitigation
Strategy. The project is slated to be completed during the FY 2016 -17 cycle; and
• Big Cypress Basin LOS project - to determine the existing and future (using three sea level
rise scenarios) flood protection level of service for this basin, including an assessment of
future land use. The project is slated to be completed during the FY 2016 -17 cycle.
5.3 RECOMMENDATION ON POLICY
The County currently addresses road design criteria in two key Code sections, as well as
capacity -based levels of service. For the purposes of this discussion, the design criteria (as
opposed to capacity) are most relevant.
Currently, the County's road design requirements in Section 19 -42 (Construction standards and
specifications) of the Code of Ordinances are that:
• "All construction, repairs and /or restorations within county public rights -of -way and
easements shall conform to the technical standards and specifications as contained in the
Florida Greenbook and the 1995 edition of the "Monroe County Public Works Manual,"
which manual is hereby adopted pursuant hereto and, by reference, incorporated herein.
• Revisions to the 1995 "Monroe County Public Works Manual" may be adopted by the
board of county commissioners by resolution. 1165
Section 114 -7 (Streets) of the County's Land Development Code includes the following design
criteria:
• The arrangement, character, extent, width, grade and location of all streets shall conform
to all the county plans and shall be considered in relation to existing and planned streets,
topographical conditions, public convenience and safety, and in their appropriate relation
to the proposed uses of the land to be served by such streets.
• Right -of -way shall be provided and dedicated to the public in accordance with the
following:
— State roads: as determined by the Florida Department of Transportation;
— Secondary roads and streets: 50 feet, with 25 feet on either side of centerline.
• Roads and streets shall be located to provide access to all adjoining land at intervals of
not more than one - quarter mile (1,320 feet) unless blocked by a natural obstacle. Access
to all adjoining property must be provided by the developer at his expense if any of the
developer's actions block natural or existing access.
• Names of subdivisions, roads and streets previously used for subdivisions in the county
shall not be given to new subdivisions unless their post office addresses are different
towns or cities. Roads and streets that form extensions, or are located along the general
63 Monroe County, Fla., Code of Ordinances ch. 19, art. II, § 19-42 (2015) and Monroe County, Fla., Land Development Code ch. 114, art. I, § 114-
7 (1987).
64 Monroe County, Fla., Land Development Code ch. 114, art. I, § 114 -2 (1992).
65 Monroe County, Fla., Code of Ordinances ch. 19, art. II, § 19 -42 (2015).
P a g e 4 7 I i a n u a r y 7 0 1 7
Monroe County Pilot Roads Project T win Lakes and Sands Communities
Final Report
projections of existing roads and streets, shall be named after the existing roads and
streets.
• Street markers and traffic- control signs shall be installed at the expense of the developer
in accordance with the county's typical standard construction details.
• The arrangement of streets in a subdivision shall either:
— Provide for the continuance or appropriate projection of existing principal streets
in surrounding areas; or
— Conform to a plan for the neighborhood to meet a particular situation where
topographical or other conditions make continuance or conformance to existing
streets impracticable.
• Minor streets shall be laid out to discourage their use by through traffic.
• Where a subdivision abuts or contains existing or proposed arterial streets, the county
engineer may require marginal- access streets, reverse frontage with screen planting
contained in a nonaccess reservation along the rear property line, deep lots with rear
service alleys, or such other treatment as may be necessary for adequate protection of
residential properties and to afford separation of through and local traffic.
• Reserve strips controlling access to streets shall be prohibited except where their control
is placed under the county, with conditions approved by the county engineer.
• Streets with centerline offsets of less than 125 feet at points of intersection with other
streets shall be avoided where possible.
• A tangent of at least 100 feet shall be introduced between reverse curves on arterial and
collector streets if required by the county engineering department.
• When connecting street lines deflect from each other at any one point by more than ten
degrees, they shall be connected by a curve with a radius adequate to ensure a sight
distance of not less than 300 feet for minor and collector streets, and of such greater radii
as the department of planning shall determine for special cases.
• Streets shall be laid out so as to intersect as nearly as possible at right angles, and no
street shall intersect any other street at less than 80 degrees.
• Property lines at street intersections shall be rounded with a minimum radius of 25 feet,
or a greater radius where the county engineer may deem it necessary. The county
engineer may permit comparable cutoffs or chords in place of rounded corners.
• Half- streets shall be prohibited, except where essential to the reasonable development
of the subdivision in conformity with the other requirements of this article, and where
the county engineer finds it will be practicable to require the dedication of the other half
when the adjoining property is subdivided. Wherever a half- street is adjacent to a tract
to be subdivided, the other half of the street shall be platted within such tract.
J a n u a y 7 0 1 7 P a g e 4 3
Monroe County Pilot Roads Project Twin Jokes and Sonds Communities
Final Report
• Dead -end streets, designed to be so permanently, shall be provided at the closed end
with a turnaround having an outside roadway diameter of at least 70 feet, and a street
property line diameter of at least 100 feet, or may be provided with a "T" type turnaround
as may be approved per "Standard Specifications and Details of Monroe County" by the
department of planning.
• Street grades, including bridge approaches, shall not exceed six percent and shall include
properly designed vertical curves.
• Paved roads and streets shall be paved at least 20 feet wide on a minimum base width of
22 feet and a minimum subgrade width of 24 feet, all as required in the county's typical
standard construction details.
• Stabilized shoulders seven feet wide shall be provided for public parking and safety
alongside roads and streets.
• The minimum crown elevation of all roads and streets in the county shall be plus 4.0 msl.
Recently, the County has begun factoring sea level rise considerations into decisions related to
road improvement projects. The factors already being considered on a project -by- project basis
are the local MHHW level, adding the 2015 fall King Tide data (for example, at the Vaca Key NOAA
Tide Gauge, County staff used 90% of maximum level and for Key West, the only gauge for ocean
side roads, County staff used 100% of the maximum level). Additionally, 5.4 inches was added to
the flooding estimate or the maximum predicted sea level rise from 2015 to 2030. A target
elevation for the edge of pavement was derived and increased by 2% for the road crown and this
target elevation was evaluated against other localized impacts such as adjacent properties.
While these considerations are already being factored into road project design by County staff, a
more comprehensive policy that takes into account the full array of site - specific conditions and
can be applied countywide is warranted. From a policy perspective, while the Board of County
Commissioners may decide upon a particular level of projected sea level rise to drive design
decisions, other considerations and constraints may prevent that goal from being achieved.
This Pilot Project provides a mechanism to tie these numerous concepts together and develop
recommendations for a countywide approach to addressing future flooding into road design
criteria. Comprehensive Plan requirements are moving in that direction, but from the County's
perspective, tying the useful life of infrastructure projects to sea level rise factors is something
already established as a policy. Monroe County Comprehensive Plan Policy 1502.1.5 states that:
Within five (5) years after the adoption of the 2030 Comprehensive Plan, Monroe
County shall initiate an inventory of existing and planned infrastructure up to the
2030 horizon, based upon the vulnerability mapping identified in Policy 1502.1.4
for capacity to accommodate projected sea -level rise of the life expectancy of that
infrastructure. Monroe County shall identify the infrastructure within those areas,
its useful life and any retrofits or capital projects necessary to address the impacts
of sea level rise. These strategies may include defense, accommodation, or and
retreat projects, or not building planned infrastructure in vulnerable locations, to
" Monroe County, Fla., Land Development Code ch. 114, art. I, § 114 -7 (1987).
P a g e 1 4 1 J a n u a r y 7 0 1 7
Monroe County Pilot Roads Project Twin lakes and Sands Communities
Final Report
address the impacts of sea level rise. Monroe County will consider developing
design criteria, in conjunction with a broader asset management process .67
Based on the case studies discussed in this Report, the Team has developed a policy approach,
and draft Ordinance attached as Appendix 2, that incorporates three key elements of design
related to roads in the face of changing environmental conditions. The Elements include:
• Design Criteria Development;
• Local Conditions Analysis; and
• Special Designation for Environmentally - Challenging Locations and Providing Meaningful
Access.
We discuss the framework for each of these Elements below.
I. Design Criteria Development
The road design requirements currently set forth in Sections 19 -42 and 114 -7 of the
County's Code are not sufficient to address the impacts of sea level rise on roadways, as
required by Monroe County Comprehensive Plan Policy 1502.1.5. These existing criteria
are not tied to the Compact or other sea level rise projections, nor do they consider sea
level rise impacts over the useful life of future road improvement projects.
It is recommended that Monroe County use an approach similar to that used in St. Johns
County in its 2012 Ordinance regarding treatment of the Greenbook recognizing that it
shall be applied to the extent that economic and environmental considerations in existing
development will allow. That approach was that design criteria were adopted by
ordinance and compliance with such County regulation is an approved Design Exception
to the Greenbook. The Design Exception for Monroe County could incorporate
consideration of the low or IPCC AR5 Median sea level rise projection, at a minimum, for
the useful life of that particular road improvement project. The Design Exception could
also include a threshold in terms of days where flooding is not exceeded. To understand
the steps in the process used to develop various design recommendations see Section 4.5
and Appendix 1 — Methodology for Development of Flood Level Estimates for the Two
Communities of this Report.
2. Local Conditions Analysis
Designing to a particular sea level rise target may not be achievable because of local
conditions that vary location to location and this should be considered in developing
design criteria. These conditions have been discussed previously in Section 3.3.
In evaluating these local conditions, County staff will have to balance these challenges
and conditions to create targets best suited for a particular roadway.
67 Monroe County, Fla., Monroe County Year 2030 Comprehensive Plan (as adopted Apr. 13, 2016), available at: http://www.monroecounty-
fl-govIDocumentview.aspx?DID=4606
ee This concept borrows from Fla. Stat. § 373.414 (2016) utilizing a similar "balancing test' to determine whether an activity over surface water
or wetlands is contrary to or in the public interest by evaluating seven express criteria.
J a n u a r y 2 0 1 7 P a g e 1 5
Monroe County Pilot Roads Project - Twin lakes and Sands Communities
Final Report
3. Special Designation for Environmentally-Challenging Locations and Providing
Meaningful Access
The final element of the policy approach is to 1) provide for a special designation of
"environmentally-challenging locations" and 2) provide for meaningful access to address
the appeal of the Jordan case in the Fifth District Court of Appeal. As discussed earlier in
this Report, that court opined that the County had a duty to "reasonably maintain" and
repair Old A1A in such a way as to result in "meaningful access." Any policy approach
should incorporate this Element to avoid the issues raised in that case regarding access
along the roadway. By defining a process to create a special designation for
environmentally-challenging locations and providing meaningful access in light of the
natural forces degradation of roadway infrastructure, the County is formally
acknowledging that meeting specific design criteria goals may not always be achievable.
Once designated, based on the local conditions analysis reduced levels of service may be
the result due to environmental, economic or property-based conditions in these areas.
Figure 13 -Sample Process Evaluation
Sample Process Flow for Road Design Draft for Discussion Purposes
Sea Level Rise
Can Road Meet
n Determine project life (Year) r Existing and future conditions Median or Low Sea
a At a minimum, incorporate »Environmental Considerations Level Rise Projection
Median or Low sea level rise z.Space Considerations with Design Criteria?
projection Impact Evaluations
If no,further evaluation
Special Designation for Meaningful Access
Environmentally Challenging Determination If Yes, Design
Locations Determine the types of Criteria
z.Identify which local factors access issues Complete
are problematic »Present to Board of County
z.Identify how design criteria Commissioners
will differ
5.4 CONCLUSIONS
Based on the foregoing, several key conclusions can be reached from this analysis that support
the adoption of a policy approach such as that outlined here in the form of an Ordinance. A draft
ordinance is included as Appendix 2 — Draft Ordinance to this Report, but the following
conclusions are relevant:
Page 1 6 II January 2017
Monroe County Pilot Roads Project Twin lakes and Sands Communities
Final Report
• The law is moving in the direction of requiring local governments to harmonize future
flood risk and the useful life of infrastructure projects. The County has already adopted
a local policy requiring this linkage.
• While there is no legal duty to provide a specific level of service for flood risk on roads,
reasonable maintenance resulting in meaningful access has been one court's
interpretation of those duties with regard to local government action.
• Developing a countywide approach for addressing these issues is preferable to case -by-
case determinations because it provides more long -term certainty for the County in
capital planning and residents in terms of expectations for levels of service.
• The lessons learned from this Pilot Project have served an important purpose related to
understanding the case -by -case differences in attempting to develop road design criteria
that address future flood risk. That said, any discussion related to road design criteria
countywide will be aided by a) better elevation data and b) a more specific vulnerability
analysis to determine the timing and magnitude of future risk related to sea level rise.
• While there is no single local government case study that has addressed all of issues in
one policy approach, case studies have addressed: a) road design criteria that incorporate
sea level rise, b) developing policy in the face of environmentally challenging road
conditions and c) case -by -case localized (or basin) criteria recognizing that levels of
service fluctuate but can still address common conditions. All of these elements
combined form the basis of the Draft Ordinance in Appendix 2.
J a n u a- y 2 0 1 7 ' F a g e 4 7
Monroe County Pilot Roads Project Twin lakes and Sonds Communities
Final Report
6 Appendix
6.1 APPENDIX 1 — METHODOLOGY FOR DEVELOPMENT OF FLOOD LEVEL
ESTIMATES FOR THE TWO COMMUNITIES
The Team conducted a series of technical processes to understand flooding recurrence in the two
pilot communities (Twin Lakes and Sands Community). The overall intent of this effort was to
identify a water elevation that represents a value for an annual return period (not to exceed 7
days) and also includes sea level rise in determining a desired final roadway elevation for
implementation.
1. First, the Team obtained the water elevation data and tidal datums from the Vaca Key
Tide Gauge for the 20 -year period from 1995 to 2015 Data from this gauge was analyzed
to determine certain values, including:
a. Tidal datum information, including a calculated value for MHHW, which is the daily
highest tide.
b. Water elevation levels, which represent calculated annual return period values
estimated from the twenty -year record. This included the identification of a
flooding level value that represents an estimated seven days annually of flooding.
c. The calculated difference between the values noted above — MHHW and a water
elevation representing flood levels which would occur 7 days out of the year —was
identified as 6" of difference.
2. Second, tidal datum values for MHHW were then obtained for the two pilot communities
through the application of the NOAA VDATUM tool, which provides tidal datum elevations
for areas not immediately adjacent to a tide gauge. These values were obtained for 2015,
adjusted as outlined in the note above, by 3 inches.
3. Third, the targeted elevation values were identified for each pilot community through a
combination of the values noted above. These included:
a. Value of the calculated 2015 MHHW value at each location.
b. The addition of 6" (from 1c above) to get to an estimated water level where, on
average, seven days of annual flooding is likely to occur in each location. Note that
"on average" indicates there may be little to no flooding some years and more
than seven days flooding in other years.
1 The twenty-year tidal record includes approximately 3 inches of sea level rise estimated for the 1995 -2015 period. To capture only the tidal
influence in this assessment, the twenty-year tidal record was adjusted using the NOAA sea level trend from the Vaca Key Tide Gauge (0.13
inches /year) to develop a constant baseline of elevations. The calculated values were then adjusted to find true 2015 levels using sea level rise
from 1992 to 2015 (3.0 inches) based on the IPCC AR5 Median sea level rise projection as identified in the Compact's Unified Sea Level Rise
Projection for Southeast Florida (2015). The differences in calculated value for MHHW and seven days of flooding were determined for the Vaca
Key Tide Gauge, which are then adjusted again for specific tidal conditions in the pilot communities. This means that the 6" value noted above
remains constant for all locations where the data from this tide gauge would be applied.
Page 48 J a n u a r y ? 0 1 7
Monroe County Pil R oads Project Twin lakes a nd Sands Communities
Final Report
c. The addition of 5.4" of sea level rise from 2015 to 2040, based on the IPCC AR5
Median sea level rise identified in the Compact's Unified Sea Level Rise Projection
for Southeast Florida (2015).
4. Fourth, the target design water levels for the communities were summarized as noted in
the table below, which identifies how each value was calculated.
Note - The values shown in the final column identify the minimum desired roadway elevation for
each of the two pilot communities. Adjustments may be made to this target elevation based on
the factors noted in the body of this report.
J wary 7017 Page 49
Elevation
addition to get
Resulting
Tidal datum
to 7 days of
Sea level rise
target
based on
flooding
estimate using
minimum
current tidal
annually based
IPCC AR5
elevation for
epoch MHHW
on 2015 sea
Median (2015 to
roads (2040) **
(NAVD88)
level
2040)
(NAVD88)
Sands Community
-1.1"
6.0"
5.4"
10.3"
Twin Lakes Community
-7.0"
6.0"
5.4"
4.4"
Note - The values shown in the final column identify the minimum desired roadway elevation for
each of the two pilot communities. Adjustments may be made to this target elevation based on
the factors noted in the body of this report.
J wary 7017 Page 49
Monroe County Pilot Roads Project Twin I okes and Sands Communities
Final Report
6.2 APPENDIX 2 — DRAFT ORDINANCE
ORDINANCE NO. -2017
AN ORDINANCE OF THE BOARD OF COUNTY COMMISSIONERS
OF MONROE COUNTY, FLORIDA, ESTABLISHING ADOPTED
DESIGN CRITERIA AND STANDARDS FOR EXISTING COUNTY
ROADS AND DESIGNATIONS FOR ENVIRONMENTALLY
CHALLENGING LOCATIONS TO ADDRESS NATURAL FORCES'
DEGRADATION AND DAMAGE TO IMPROVED COUNTY ROADS,
THE SIGNIFICANT COSTS OF CONSTRUCTION, MAINTENANCE,
REMEDIATION, REPAIR, AND OPERATIONS INCURRED WITH
RESPECT TO THESE NATURALLY DAMAGED ROADS;
RECOGNIZING AND DEFINING MEANINGFUL ACCESS FOR USERS
OF SUCH ROADS; PROVIDING FOR CONFLICTS OF LAW;
SEVERABILITY; AND AN EFFECTIVE DATE.
WHEREAS, pursuant to Florida Statutes ( "F.S. ") Ch. 334, the Florida Department of
Transportation ( "FDOT ") has the power to develop and adopt uniform minimum standards and
criteria for the design, construction, maintenance, and operation of public roads; and
WHEREAS, Section 336.045, F.S. provides for the uniform minimum standards for
design, construction, and maintenance of County roads, as provided by FDOT; and
WHEREAS, FDOT has adopted uniform minimum standards and criteria for the design,
construction, maintenance, and operation of public roads and published such standards and
criteria in the Manual of Uniform Minimum Standards for Design, Construction and
Maintenance for Streets and Highways, which is commonly known as the "Florida Greenbook ";
and
WHEREAS, the Florida Greenbook' standards are intended for use on all new
construction projects of the state highway and federal aid systems, and it is understood that
the standards of the Florida Greenbook cannot be applied completely to all reconstruction and
maintenance type projects; however, the Florida Greenbook standards shall be applied to the
nearest economically and environmentally reasonable and practical extent; and
WHEREAS, Chapter 14 of the Florida Greenbook allows for "Design Exceptions" in
instances where it becomes necessary to deviate from the Florida Greenbook's criteria; and
WHEREAS, Section B of Chapter 14 of the Florida Greenbook states that counties may
adopt design criteria for local subdivision roads and /or residential streets by ordinance, and
compliance with such regulations is an approved Design Exception; and
WHEREAS, erosion, flooding, and other similar environmental impacts may pose
challenges to the effective construction, maintenance, remediation, repair, and operation of
improved County roads now and in the future; and
P a g e 5 0 1 a n L a r y 7 0 1 7
Monroe County Pilot Roads Project -- Twin lakes and Sands Communities
Final Report
WHEREAS, Monroe County has adopted Policy 1502.1.1 in the Climate and Energy
Element of its Comprehensive Plan stating that "Prior to incorporating a new project to the
Capital Improvements Element, Monroe County shall assure that it is reviewed for
recommendations to increase resiliency and account for the impacts from climate change,
including but not limited to, sea level rise and storm surge. Monroe County shall evaluate
financial expenditures to fund repairs, reconditioning of deteriorating infrastructure and new
infrastructure improvements within or proximate to vulnerable areas to manage public
investments appropriately. Monroe County shall focus on level of service standards, as one of
the points of analysis, to assure that infrastructure useful life and service expectations can be
met in the face of climate change impacts "; and
WHEREAS, due to economic and environmental considerations, including but not
limited to forces of nature and local conditions as defined in Section3(d) , Monroe County
seeks to create a Design Exception that establishes design criteria and standards for existing
improved County roads and future County road improvements that consider(s) the present
and future impacts of sea level rise and the projected duration of related flooding; and
WHEREAS, the County also seeks to create a designation for Environmentally
Challenging Locations and define meaningful access for users of improved County roads; and
WHEREAS, the County has completed a "Pilot Project" to develop a methodology to
create design criteria and standards for road improvement projects in two (2) neighborhoods
within Monroe County, and is developing a countywide roads study to determine appropriate
design criteria and standards for road improvement projects countywide; and
WHEREAS, once Monroe County has finalized this countywide roads study, the County
will revisit these design criteria and standards, as necessary; and
WHEREAS, the Board finds that adoption of the provisions set forth in this ordinance
protects the fiscal solvency of Monroe County, limits and reduces fiscal waste, and is in the
best interest of the residents of Monroe County.
NOW, THEREFORE, BE IT ORDAINED BY THE BOARD OF COUNTY COMMISSIONERS OF
MONROE COUNTY, FLORIDA:
SECTIONS 1: Section of the Monroe County Code shall be amended /created to
read as follows:
Sec. - DEFINITIONS.
The following words, terms, and phrases shall have the following meanings:
"Environmentally Challenging Location(s)"' means
(a) Locations where typical road design criteria and standards are not economically
practical, or are not environmentally practical, due to naturally occurring conditions
including, but not limited to:
January 7017 Page 51
Monroe County Pilot Roads Project Twin lakes and Sands Communities
Final Report
1. Conditions rationally arising from, related to, or in connection with sea level
rise or flooding, that impact an improved County road to such an extent that
one or more vehicle classes and /or vehicle types may not be able to travel over
or along such road without sustaining damage or risking the safety of its
passengers; or
2. Conditions rationally arising from, related to, or in connection with sea level
rise or flooding, that directly or indirectly interfere with the drainage,
maintenance, or repair of an improved County road; or
3. Conditions rationally arising from, related to, or in connection with sea level
rise, that cause the drainage, maintenance, or repair of an improved County
road to directly or indirectly have an adverse or detrimental impact on a
threatened or protected environmental or natural resource (such as, but not
limited to threatened or protected animal or plant species, threatened or
protected habitat types, buffers thereto, and /or wetlands); or
4. Conditions rationally arising from, related to, or in connection with sea level
rise or flooding, due to which the drainage, maintenance, or repair of an
improved County road necessary to keep such road at a prior level of service
standard, would increase, intensify, or exacerbate, the adverse or detrimental
impact of that road on a threatened or protected environmental or natural
resource; or
(b) locations where the local conditions as defined in Section 3(d) prevent the Design
Exception from being met;
Improved Roads shall mean roads or portions thereof owned by the County, and roads
or portions thereof that the County has regularly maintained or repaired for the past seven (7)
years.
Meaningful access means the actual ability to use a vehicle on an improved County
road, or a portion thereof, to practicably access to privately -owned real property.
SECTION 2: Section of the Monroe County Code shall be amended /created to
read as follows:
Sec. - APPLICABILITY.
This ordinance shall apply to Improved Roads and /or future projects on Improved
Roads.
The County shall apply the design criteria set forth herein and shall, by resolution
designate Improved Roads as roads impacted by Environmentally Challenging Conditions,
taking into consideration factors including but not limited to the following:
0 environmental conditions,
P a g e 5 7 I i a n c a y J 0 1 7
Monroe County Pilot Roads Project Twin lakes and Sands Communities
Final Report
• historical and projected physical damage due to conditions rationally arising
from, related to, or in connection with sea level rise and flooding, (including,
but not limited to the frequency of such conditions and damage),
• historical and projected maintenance and repair costs, and
• economically beneficial use(s) of privately -owned real property.
SECTION 3: Section of the Monroe County Code shall be amended /created to
read as follows:
Sec. - DESIGN CRITERIA.
(a) The design criteria listed herein are being adopted for the express purpose of
serving as an approved Design Exception to the uniform minimum standards and
criteria for the design, construction, maintenance, and operation of Improved
Roads or future road improvement projects, pursuant to Section B, Chapter 14 of
the Florida Greenbook stating if the County "has adopted by ordinance design
criteria for local subdivision roads and /or residential streets, compliance with those
regulations is an approved design exception."
(b) For future road improvement projects, the County shall make a determination of
the year that it is expected to be in service. That determined year shall be the basis
to establish an estimated range of sea level rise projections developed by the
Southeast Florida Regional Climate Change Compact ( "Compact "). The County may
use another professionally accepted method for estimating the range of sea level
rise projections or use the range of sea level rise projections developed by another
agency. The County shall incorporate the range of sea level rise projections by
using the Median or Low level (for the Compact this is one in the same) as a
minimum criterion for design of the road improvement project. If the County uses
another professionally accepted method for estimating the range of sea level rise
projections or uses the range developed by another agency, the lowest estimated
level of sea level rise shall be utilized as a minimum criterion for design of the future
road improvement project.
(c) To determine the final minimum edge of pavement elevation for future road
improvement projects, the County shall:
1. Establish the tidal datum elevation Mean Higher High Water ( "MHHW ") using
the current tidal epoch (1983 -2001) with a base year of 1992 at the site of the
road improvement project in North American Vertical Datum of 1988 (NAVD
88). This is the project site MHHW.
2. Add to the project site MHHW, the difference between the MHHW at the
reference gauge and the elevation that represents the water level with an
estimated 7 day annual recurrence interval at the reference gauge, which is the
most proximate National Ocean and Atmospheric Administration ( "NOAA ") tide
gauge. The difference is calculated using the 20 year tidal record from the
J a n u a, y 7 0 1 7 ; P a g e 5 3
Monroe County Pilot Roads Project Twin I okes and Sands Communities
Final Report
reference gauge and detrendingthe data to the base year of 1992 by subtracting
NOAA's published Sea Level Trend for this reference gauge.
3. Add estimated sea level rise projection as established in 3(b) to the 7 day
recurrence flood interval. Adjust this flood elevation to the current design year
by adding the appropriate calculated amount to account for sea level rise. The
data are adjusted to the current year by adding the projection as established in
3(b) from 1992 up to and including the project year.
(d) For future road improvement projects, the County shall also analyze local
conditions that may influence a particular road design or prevent the design criteria
in Sections 3(b) and (c) from being met. Each condition shall be evaluated on its
own merit, although each factor need not be given equal weight. The following
conditions shall be considered and balanced using the County's best professional
judgment:
I. Physical site constraints;
2. Current road conditions and elevations;
3. Current elevation of adjacent properties;
4. Sensitivity of the land or mitigation requirements to be met;
5. Water quality requirements;
6. Right of way needs;
7. Availability of land to accommodate drainage;
8. Elevation of water table in relation to road elevation;
9. Impacts to access for private property (driveways);
10. Future maintenance needs and costs including staffing requirements; and
11. Number of developed properties that the subject road services as the sole
means of access.
(e) If the design criteria in Sections 3(b) and (c) cannot be met for a future road
improvement project, or if the criteria in Sections 3(b) and (c) can be met, but the
conclusion of the local conditions analysis in Section 3(d) indicates that it would not
be economically or environmentally practical to meet it, the County may designate
the Improved Road to be an Environmentally Challenging Location.
(f) Due to forces of nature and local conditions rationally arising from, related to, or in
connection with sea level rise and flooding, access to property by County roads that
are located in Environmentally Challenging Locations may be limited. In such
instance, the Board of County Commissioners may determine that such forces of
Page 54 1 ianaary 7017
Monroe County Pilot Roads Project Twin lakes and Sands Communities
Final Report
nature or local conditions have made it not economically or environmentally
practical, to maintain such County roads by the County's general road standards or
meet those in this Design Exception, and may, by resolution, designate such a
County road as being located in an Environmentally Challenging Location.
(g) For existing Improved Roads that are or may be designated as being located in
Environmentally Challenging Locations, the minimum standards of maintenance
shall differ from the County's general minimum standards of maintenance due to
the local conditions of Environmentally Challenging Locations.
(h) Improved Roads in Environmentally Challenging Locations may experience local
conditions that rationally necessitate that the County's design criteria for general
road standards or those in this Design Exception are altered or will be altered to
the extent that the following conditions may be present in providing meaningful
access:
Periods of time when the Improved Road may be partially or fully submerged
with saltwater, brackish water, or rainwater.
2. Periods of time when the Improved Road may be buried, covered, or blocked
by floating vegetation (e.g., seaweed, mangrove debris, and the like), or sand
or soil, after road inundation conditions subside.
3. Temporally variable sub - standard lane widths, single lanes, and varying
maintained width(s) in different locations along the Improved Road.
4. Limited access by vehicle class, type, size, or weight.
5. No assurance that emergency vehicles (e.g., fire, ambulance, police) or public
service vehicles (e.g., garbage collection, mail service, parcel delivery, school
bus service) can use or routinely use such Improved Road to access privately -
owned real property.
6. Paved surfaces with intermittent disruptions (e.g., 'potholes,' cracks, or other
loose material) due to frequent inundation.
7. Other similar conditions that directly or indirectly cause the Improved Road to
be in a substandard state.
(i) Private property that is accessed by Improved Roads that are located in, or will be
located in, Environmentally Challenging Locations may encounter access issues as
set forth above. Factors that may affect access to private property include, but are
not limited to:
1. The original natural physical characteristics and features of the area where the
parcel is located;
J a n u a r y 7 0 1 7 1 P a g e 5 5
Monroe County Pilot Roads Project Twin lakes and Sands Communities
Final Report
2. The original method of access to the parcel from the location of the nearest
Improved Road;
3. Changes to the physical or configurative characteristics of the area in which the
parcel is located, whether natural or man -made; and
4. The inability of the County to repair a Improved Road due to federal, state, or
other local government laws or regulations, or due to a decision by a court of
competent jurisdiction or by an administrative hearing officer.
(j) Access to private property served by Improved Roads in Environmentally
Challenging Locations may be limited by local conditions beyond the practical or
reasonable control of the County. Resulting circumstances may include, but are not
limited to:
1. Roadway conditions that necessitate the use of a four -wheel drive (or other
specially designed) vehicle, or a vehicle that rides higher off of the ground, for
passage.
2. Periods of time before roadway drainage and /or repair may be accomplished
when vehicular access is limited.
3. Extended periods during which time access from the Improved Road or the
County road itself is impassable to one or more vehicle classes, types, sizes, or
weights.
4. Instances where roadway repair cannot legally commence, or be accomplished,
without permits issued by federal or state agencies due to adverse or
detrimental environmental or natural resource impacts.
(k) Except as otherwise determined by the Board of County Commissioners, the
County shall have no affirmative duty to construct, or permit others to construct,
new roads, to upgrade roads, or to otherwise make particular improvements to
Improved Roads in Environmentally Challenging Locations.
(1) The County has no duty or obligation to make particular improvement to or
upgrade of any portion of an Improved Road in an Environmentally Challenging
Location situated adjacent to private property that has been acquired at a time
when any of the conditions or circumstances listed in Section 30) of this ordinance
are already in existence, or after the County has designated the County road as
provided by Section 2 of this Ordinance.
(m) Nothing contained herein shall prohibit private property owners served by existing
Improved Roads in Environmentally Challenging Locations from petitioning the
Board of County Commissioners for a vacation of the road, or the establishment of
a Municipal Services Benefit Unit ( "MSBU ") and /or a Municipal Services Taxing Unit
( "MSTU ").
P a g e 5 6 1 J a n u a, y 7 0 1 7
Monroe County Pilot Roads Project Twin lakes and Sands Communities
Final Report
(n) The Board of County Commissioners may in their own discretion abandon an
Improved Road in Environmentally Challenging Locations as authorized pursuant to
F.S. 336.09
SECTION 4: - CONFLICTS OF LAW.
Any provision of another County ordinance or regulation relating to road maintenance
or development of private property on Improved Roads affected by forces of nature that is in
conflict with this Ordinance is repealed to the extent of such conflict.
Except as provided in the paragraph above, whenever the requirements or provisions
of this Ordinance are in conflict with the requirements or provisions of any other lawfully
adopted ordinance or statute, the more restrictive requirements shall apply.
SECTION 5: - SEVERABILITY.
It is the Board's intent that if any section, subsection, clause, or provision of this
Ordinance is deemed invalid or unconstitutional by a court of competent jurisdiction, such
portion shall become a separate provision and shall not affect the remaining provisions of this
ordinance. The Board of County Commissioners further declares its intent that this Ordinance
would have been adopted if such invalid or unconstitutional provision is not included.
SECTION 6: - INCLUSION IN CODE OF ORDINANCES
The provisions of this ordinance shall be included and incorporated in the Code of
Ordinances of the County of Monroe, Florida, as an addition or amendment thereto, and shall be
appropriately renumbered to conform to the uniform numbering system of the Code.
SECTION 7: TRANSMITTAL AND EFFECTIVE DATE
This Ordinance will take effect upon its filing with the Office of the Secretary of the
Florida Department of State as per F.S. 125.66(2).
PASSED AND ADOPTED by the Board of County Commissioners of Monroe County,
Florida, at a regular meeting of said Board held on the day of , 2017.
Mayor George Neugent
Mayor Pro Tern David Rice
Commissioner Danny L. Kolhage
Commissioner Heather Carruthers
Commissioner Sylvia Murphy
Janua 7 0]7 Page 57
Monroe County Pilot Roads Project Twin lakes and Sands Communities
Final Report
(SEAL)
ATTEST: KEVIN MADOK, Clerk BOARD OF COUNTY COMMISSIONERS OF
MONROECOUNTY, FLORIDA
By:
Deputy Clerk
Mayor /Chair
By:
P a g e 5 8 1 J a n u a r y 7 0 1 7
ERIN L. DEADY. P.A.
"' I
PARSONS
A�� Wsp BR/NCKERHOFF