LTC 289-2020 Miami-Dade Back Bay Coastal Storm Risk Management Feasibility Study Public CommentsDocuSign Envelope ID: 06041E5A-931F-40E 6-B7AE -9095AD 6E9C79
MIAM I BEACH
OFFICE OF TH E CITY MANAGER
NO. LTC #
289-2020
LETTER TO COMMISSION
TO: Mayor Dan Gelber and Members of the City Commission
FROM: Jimmy L. Morales, City Manager
j¡DocuSigned by:
he!%e"
DATE: August 20, 2020
SUBJECT:
Comments
Miami-Dade Back Bay Coastal Storm Risk Management Feasibility Study Public
The purpose of this Letter to Commission is to provide the Mayor and City Commission with an
update on the comments provided to the United States Army Corps of Engineers (USAGE) Back
Bay Coastal Storm Risk Management Feasibility Study (Attached).
The USAGE Back Bay Coastal Storm Risk Management Feasibility Study is investigating
solutions to reduce the damage and risks from flooding that comes from storm surges associated
with hurricanes and tropical storms amplified by sea level rise. The study focuses on critical
infrastructure and areas of the county that are vulnerable to coastal storms.
On June 5, 2020, the USAGE, in partnership with Miami-Dade County, released the Draft
Integrated Feasibility Report and Programmatic Environmental Impact Statement for the Miami-
Dade Back Bay Coastal Storm Risk Management Feasibility Study. The public had until August
19, 2020 to comment and provide feedback to the USAGE on the plan.
Please find attached the comments the administration submitted. The comments/questions were
focused on the main areas below, including but not limited to:
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Alignment of the USAGE Coastal Storm Risk Management Feasibility Study, which is
focused on beach erosion, with the Miami-Dade Back Bay Coastal Storm Risk
Management Feasibility Study;
Support efforts to upgrade vulnerable public and private seawalls to increase coastal
protection and reduce storm surge risks;
Coordination with Miami Beach's Land Development Regulations;
Structure/Building requirements and inclusion of dry-floodproofing for residential
properties where elevation is not a feasible option;
Further consideration of Natural and Nature Based Infrastructure (NNBF) in the study
Should you have any questions, please contact Elizabeth Wheaton at 305-673-7010 x6121 or at
ewheaton@miamibeachf]_gov
Attachment - Letter to the United States Army Corps of Engineers regarding comments to the
Back Bay Coastal Storm Risk Management Feasibility Study
JLM/ATH/ESW/FT
M IA M I BEACH
OFFICE OF THE CITY MANAGER
City of Miami Beach, 1700 Convention Center Drive, Miomi Beach, FL 33139, www.miamibeachfl.gov
August 19, 2020
Ms. Justine Woodward
U.S. Army Corps of Engineers, Norfolk District
803 Front Street, Norfolk, Virginia 23510
Subject: Miami-Dade Back Bay Coastal Storm Risk Management Feasibility Study
Dear Ms. Woodward,
The City of Miami Beach is respectfully providing the following comments on the Miami-Dade Back Bay
Coastal Storm Risk Management Feasibility Study released in June 2020. The City of Miami Beach has been
investing in public infrastructure to protect the City from sea level rise and impacts from hurricanes and
storm surge. Over the next ten years, the City will be investing over $600 million in upgrading stormwater
system and raising roads and public property. Incremental adaptation of both public and private
infrastructure is critical to ensure the long-term viability of our community. The City of Miami Beach is
encouraged that the non-structural solutions for private properties and critical infrastructure are an
integral component to the U.S. Army Corps of Engineers (USACE) study.
Increasing resilience as a region is paramount to the City of Miami Beach and our many partners.
Resilience is the foundation of Resilient305, an intergovernmental resilience strategy that was co-
produced by Greater Miami and the Beaches, a unique partnership of the City of Miami Beach, the City of
Miami and Miami-Dade County. The strategy was launched officially on May 30, 2019 and was created
with the help of expert consultants and community partnerships. Through the resilience strategy actions,
we aim to address our place-based challenges, enhancing our climate resilience through design and
planning for the future. Specific priority actions in the strategy to reduce flood risk include: Reduce Back
Bay Flooding, Preserve and Restore Biscayne Bay, Build Reef Biodiversity and Defenses, Bolster our
Beaches, Expand Nature-based Infrastructure, and Prepare your Property. The full strategy can be
accessed at www.mbrisingabove.com/your-city-at-work/ resilience-strategy.
Miami Beach's comments on the Miami-Dade Back Bay Coastal Storm Risk Management Feasibility Study
are included below:
COMMENTS
1. The USACE Jacksonville District is currently working on Coastal Storm Risk Management Feasibility
Study focused on the 9.3 mile stretch of the Atlantic shoreline from Bakers Haulover Inlet to
Government Cut. This study seeks to reduce storm damages to property and infrastructure within
the pro ject area over a SO-year period of analysis. It is im perative that these tw o studies are
com plem entary and are closely co ordinated to ensure a holistic approach to sto rm surge
pro tection.
2. In M iam i Beach, the shoreline abutt ing Biscayne Bay is over nine-tim es the length of the city's
A tlantic shoreline. O ver 90% of the seaw alls along Biscayne Bay and associated w aterw ays are
privately ow ned. Upgrading degrading seaw alls and seaw alls w ith low elevations is critic al to
reducing im pacts of storm surge events. W ill the USA CE support the City's eff ort s regarding
upgrading vulnerable private seaw alls to increase coastal pro tection and reduce storm surge
risks? A lso, Is USA CE considering lim estone rocks layers (w hic h allow s w ater to flow under
seaw alls causing flooding in low areas despite protection fr om seaw alls )?
3. Non-Stru ctural Solutions
a. M iam i Beach's Land Developm ent Regulations pro vide m inim um standards fo r new
developm ent and redevelopm ent. The City 's LDR 's are designed to help reduce risks fr om
storm surge and sea level rise vulnerability, such as m inim um lot elevations and m inim um
finished floor elevations. W ill the study com plem ent local polici es and m inim um
standards?
b. FEM A is in the process of updating their flood zo ne m aps fo r our area. The final design
should utilize the new FEM A flood m aps. In lieu of elevating, FEM A requires non-
residential struct ures to be dry -flood-proofed to an elevation "BFE+1 feet", w e
recom m end that the existing structures be qualified fo r dry -flood-proof m itigatio n
program w hen the low est floor elevation is low er than "BFE-3 feet" or the lowest floor is
lower than "Grade Elevation -3 ft".
c. About 64% of Miami Beach buildings are Pre-FIRM Construction, majority of these
buildings are elevated below 100-year flood elevation and they are vulnerable to a flood
event. Please consider including these existing buildings within properties that can be
qualified for USACE mitigation program. Also, will the USACE consider dry-flood proofing
for residential properties where elevation is not a feasible option?
d. Can USACE please share the Water Surface Elevation (WSE) data for our community and
the FEMA Flood Insurance Study (FIS) data?
4. Natural and Nature Based Infrastructure (NNBF) and Environmental Impacts
a. The protection and preservation of Biscayne Bay and associated ecosystems is necessary
to ensure the long-term viability of the region. NNBFs provide habitat and are proven to
reduce impacts of storm surge and increase coastal protection. We urge the USACE to
consider expanding the use of NNBFs in the study, particularly in the north Biscayne Bay
basin and pursue subsequent evaluations of the flood risk reduction benefits and co-
benefits of natural infrastructure in conjunction with traditional grey infrastructure.
Miami Beach is using living shorelines, reef restorations, and green infrastructure, as well
as tools fo r storm surge pro tection in a cost-effective manner. We stro ngly request the
USACE to support the City's efforts and further consider natural infrastructure, such as
living shorelines/green infr astru cture and coral restoration.
b. W e also request further studies regarding potential adverse impacts to natural resources
and water quality. Environm ental im pacts from the largescale structural solutions will
im pact the natural environm ent, including sensitive seagrass and coral habitat. We are
concern ed about the eco nom ic im pacts subsequently from these environmental impacts
to our local fisheries, recreation and tourism , as well as ecosystem serv ices like water
quality and wave attenuation.
c. W e request that the USACE con sider utilizing the actual flow dynamics associated with
high storm surge conditions and hurricane events in order analyze the potential for
strategic attenuation methods including NNBFs such as spoil islands, flood channels,
reefs, and m angro ves.
The City of M iam i Beach deeply cares about the outcom es of this study and urges the USACE to consider
our recom m endations. The City of M iam i Beach is a leader in clim ate change and sea level rise adaptation
and m itigation. W e hope th e USACE wi ll consider the solutions and policies we have been implementing.
It is im port ant fo r non-structural solutions to be integrated with existing City policies and coordinated
closely with on-going USACE studies. W e will be glad to further discuss our recommendations and any
questions you m ay have.
Sin].e rely,