C7K-Amend The Stormwater Management Master Plan For All Tidal Boundary ConditionCOMMISSION ITEM SUMMARY
Condensed Title:
A Resolution Of The Mayor And City Commission Of The City Of Miami Beach, Florida, Approving The
Recommendation Of The Flooding Mitigation Committee To Amend The Stormwater Management Master
Plan (Commission Adopted November 14, 2012) By Modifying The Design Criteria For The Tailwater
Elevation From 0.5 Ft-NAVO To 2.7 Ft-NAVO For All Tidal Boundary Conditions.
Ke Intended Outcome Su orted:
Item Summary/Recommendation:
At its January 28, 2014 meeting, the Flooding Mitigation Committee unanimously voted to recommend
changing the Stormwater Management Master Plan (Commission adopted November 14, 2012) tailwater
elevation design criteria from 0.5 ft-NAVO to 2.7 ft-NAVO for all tidal boundary conditions. The tailwater
elevation design criteria approved in the Stormwater Management Master Plan is 0.5 feet-NAVD.
The discussion and formulation of this criteria was accomplished during the January 21, 2014 meeting of
the mayor's Blue Ribbon Panel on Flooding. The Panel discussion suggested working with peak tidal
values rather than mean values. A peak tidal elevation of 2.1 ft-NAVO was selected based upon historical
data. An additional 7 inches of projected sea level rise based upon data published by the United States
Army Corp of Engineers (ACOE) was added to the 2.1 to reach a final figure of 2.7 NAVO. The Public
Works Department recommends approval of this new tailwater design criteria of 2.7 NAVO based upon
peak historical tidal values and published ACOE data regarding sea level rise as the next step in our
ongoing efforts to combat flooding within the City of Miami Beach.
Currently there are three (3) neighborhoods in active construction: Central Bayshore (70% complete),
Lake Pancoast (95% complete), and Venetian Islands (10% complete). A Design-Build contract has been
awarded for Lower North Bay Road neighborhood. The Palm & Hibiscus Islands Neighborhood is
currently in the negotiation process for Design-Build Services.
This new criteria may have a significant impact on the design and construction of the above referenced
projects. The City shall determine if these criteria shall be applicable to these projects
THE ADMINISTRATION RECOMMENDS APPROVING THE RESOLUTION.
Advisory Board Recommendation:
I N/A
Financial Information:
Source of Amount Account
Funds:
OBPI 1
2
Total
Financial Impact Summary: Based upon some very preliminary estimates, the Public Works Department
believes this would add approximately $150M -$200M to the cost of the roadway and neighborhood
stormwater improvements above the funding requirements already identified by the Stormwater
Management Master Plan. An additional 30-40 pump stations will be required, which will also raise issues
of the location in neighborhoods.
City Clerk's Office Legislative Tracking:
ETC
T:\AGENDA
MIAMI BEACH 383
AGENDA ITEM --,.C_7...,__/( ........... _
DATE rJ-ft?:~/V
~ MIAMI BEACH
City of Miami Beach, 1700 Convention Center Drive, Miami Beach, Florida 33139, www.miamibeochfl.gov
TO:
FROM:
DATE:
SUBJECT:
COMMISSION MEMORANDUM
Mayor Philip Levine and Members of he City clmmission
Jimmy L. Morales, City Manager ~
February 12, 2014
A RESOLUTION OF THE MAYOR D CITY COMMISSION OF THE CITY OF MIAMI
BEACH, FLORIDA, APPROVING HE RECOMMENDATION OF THE FLOODING
MITIGATION COMMITTEE TO AMEND THE STORMWATER MANAGEMENT MASTER
PLAN (COMMISSION ADOPTED NOVEMBER 14, 2012) BY MODIFYING THE DESIGN
CRITERIA FOR THE TAILWATER ELEVATION FROM 0.5 FT-NAVO TO 2.7 FT-NAVO
FOR ALL TIDAL BOUNDARY CONDITIONS.
BACKGROUND
At its January 28, 2014 meeting, the Flooding Mitigation Committee unanimously voted to
recommend changing the Stormwater Management Master Plan (Commission adopted November
14, 2012) tailwater elevation design criteria from 0.5 ft-NAVO to 2.7 ft-NAVO for all tidal boundary
conditions. The tailwater elevation design criteria approved in the Stormwater Management Master
Plan is 0.5 feet-NAVO.
The discussion and formulation of these criteria was accomplished during the January 21, 2014
meeting of the mayor's Blue Ribbon Panel on Flooding. The Panel discussion suggested working
with peak tidal values rather than mean values. A peak tidal elevation of 2.1 ft-NA VD was selected
based upon historical data. An additional 7 inches of projected sea level rise based upon data
published by the United States Army Corp of Engineers (ACOE) was added to the 2.1 to reach a
final figure of 2.7 NAVO. The Public Works Department recommends approval of this newtailwater
design criteria of 2.7 NAVO based upon peak historical tidal values and published ACOE data
regarding sea level rise as the next step in our ongoing efforts to combat flooding within the City of
Miami Beach.
ANALYSIS
Currently there are three (3) neighborhoods in active construction: Central Bayshore (70%
complete), Lake Pancoast (95% complete), and Venetian Islands (10% complete). A Design-Build
contract has been awarded for Lower North Bay Road neighborhood. The Palm & Hibiscus Islands
Neighborhood is currently in the negotiation process for Design-Build Services.
This new criteria may have a significant impact on the design and construction of the above
referenced projects. The City shall determine if these criteria shall be applicable to these projects.
FINANCIAL IMPACT
Based upon some very preliminary estimates, the Public Works Department believes this would add
approximately $150M -$200M to the cost of the roadway and neighborhood stormwater
improvements above the funding requirements already identified by the Stormwater Management
Master Plan. An additional 30-40 pump stations will be required, which will also raise issues of the
location in neighborhoods.
CONCLUSION
The Administration recommends adoption of the Resolution.
JJ/J JLMl~JflDM/BAM/DS
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