Requests for Proposals_Structural Modifications to Floodwall LeveeMasterpiece on the Mississippi
Dubuque
kraal
AIMAmea'IcaCity
111111
2007
TO: The Honorable Mayor and City Council Members
FROM: Michael C. Van Milligen, City Manager
SUBJECT: Issue RFP for Structural Analysis of the Levee and Floodwall System
DATE: July 22, 2010
Planning Services Manager Laura Carstens, City Engineer Gus Psihoyos and Public
Works Director Don Vogt recommend City Council authorization to issue a Request for
Proposals for structural analysis of the Dubuque levee and floodwall system, in
accordance with the levee certification requirements of the National Flood Insurance
Program regulations.
I concur with the recommendation and respectfully request Mayor and City Council
approval.
MCVM:jh
Attachment
cc: Barry Lindahl, City Attorney
Cindy Steinhauser, Assistant City Manager
Laura Carstens, Planning Services Manager
Gus Psihoyos, City Engineer
Don Vogt, Public Works Director
Mic ael C. Van Milligen
Masterpiece on the Mississippi
TO: Michael Van Milligen, City Manager
FROM: Laura Carstens, Planning Servicc, Marc ger
Gus Psihoyos, City Engineer Don Vogt, Public Works Director
SUBJECT: Issue RFP for Structural Analysis of the Levee and Floodwall System
DATE: July 21, 2010
Dubuque
biergel
AN- America Cfty
11 11 IF
2007
INTRODUCTION
This memo requests City Council authorization to issue a Request for Proposals (RFP)
for structural analysis of the Dubuque levee and floodwall system, in accordance with
levee certification requirements of Section 65.10 of the National Flood Insurance
Program (NFIP) regulations.
BACKGROUND
The City of Dubuque has signed a two -year Provisionally Accredited Levee (PAL)
agreement with the Federal Emergency Management Agency (FEMA). The PAL
agreement expires on May 17, 2011.
The City of Dubuque must certify compliance with federal regulations that the Dubuque
levee system provides 100 -year flood protection for the community. This certification
must be submitted before May 17, 2011 and be signed by a professional engineer. We
plan to have a member of the City's Engineering Department provide this certification.
DISCUSSION
The U.S. Army Corps of Engineers (USACE) prepared the June 2010 Engineering
Technical Review Report on the Dubuque Levee System at no cost to the City. This
engineering technical review is for the adequacy of the levee for the 100 -year flood
event. Overall, our levee system meets or exceeds most standards.
This report is not a levee certification report, however. The USACE report identified the
need for further structural analysis of the levee and floodwall system. The USACE will
not undertake this analysis. Consequently, City staff recommends retaining a qualified
engineering firm to conduct the structural analyses required for NFIP certification.
Issue RFP for Structural Analysis of the Levee and Floodwall System
Page 2
The scope of services would be the embankment and foundation stability analyses
required by FEMA for levee certification under Section 65.10 of the NFIP regulations.
The analyses provided shall evaluate expected seepage during loading conditions
associated with the base blood and shall demonstrate that seepage into or through the
levee foundation and embankment will not jeopardize embankment or foundation
stability.
The factors that shall be addressed in the analyses include:
• Depth of flooding;
• Duration of flooding;
• Embankment geometry and length of seepage path at critical locations;
• Embankment and foundation materials;
• Embankment compaction;
• Penetrations;
• Other design factors affecting seepage (e.g., drainage layers); and
• Other design factors affecting embankment and foundation stability (e.g., berms).
Funding for these engineering services can be covered by the Flood Control Levee
Certification Project CIP ( #720 -2155) which has an FY 2011 balance of $150,000.
RECOMMENDATION
City staff recommends that the City Council authorize the issuance of an RFP for
structural analysis of the Dubuque levee and floodwall system, in accordance with levee
certification requirements of Section 65.10 of the NFIP regulations.
LC /mkr
cc: John Klostermann, Street & Sewer Supervisor
Bob Schiesl, Assistant City Engineer
Deron Muehring, Civil Engineer
Kyle Kritz, Associate Planner