Hart Park and Western Milwaukee Levee System Accreditation Projects

MMSD reviewed the entire levee system and identified improvements required for the system to be accredited FEMA. Improvements include adding additional height to levees and floodwalls at several locations, storm sewer improvements, and sewer rehabilitation.

Project Update

The Milwaukee Metropolitan Sewerage District (MMSD) is working towards the development of a levee system accreditation submittal to the Federal Emergency Management Agency (FEMA) for the Hart Park and Western Milwaukee levee system. Accrediting the levee system will allow recognition of the flood risk reduction benefits when floodplain maps are revised. MMSD will submit a levee system accreditation request to FEMA on behalf of the City of Milwaukee and the City of Wauwatosa. The request will be submitted when the construction is completed for the levee accreditation projects and the Western Milwaukee Phase 2B project.

Project Overview

For FEMA to recognize the completed levee system's flood risk reduction benefits requires a levee system accreditation application to FEMA for the entire Menomonee River levee system. Once FEMA approves a levee system application, remapping the floodplain in the surrounding project area can proceed.

The FEMA review process is expected to take up to three years. Some structures will remain in the mapped floodplain after the levee system is completed. These structures remaining in the floodplain will be evaluated for other flood risk reduction approaches, such as voluntary floodproofing and voluntary acquisition.

Ahead of the levee system accreditation submittal to FEMA, MMSD has reviewed FEMA standards for the entire system and has identified several improvements to the system that are required for the system to be accredited.

The levee system improvements are needed for the following reasons:

River flood levels have been updated since the original Hart Park Levee Project.
Projects downstream of Hart Park were implemented differently than the original design assumptions causing changes in flood elevations.
FEMA expectations and standards for levee systems have changed after high-profile levee failures since the Hart Park levee system design was completed.
Improvements have been identified for pipes crossing or near the levee where pipe inspections indicated pipe rehabilitation is needed.
Clarifications of FEMA standards for storm sewers have identified the need for new pipe closure capability for floods higher than the design flood.

Planned Improvements for the Levee System include:

Levee/floodwall improvements: Several locations have been identified where additional height or freeboard is needed to meet FEMA standards.
Storm sewer improvements: Several storm sewer systems have been identified where pipes will have closures added or will extend further downstream so that closures do not have to be installed.
Sewer rehabilitations: inspections of pipes crossing or near the levee system have identified deteriorated conditions that will be repaired.

Project Benefits

Reduce flood risk on an estimated sixty-two structures
Reduce flood insurance costs

Partners

Project Timelines

Levee and Floodwall Improvements

Spring 2021 – 2023 – Design

2024 – Construction

Storm Sewer Improvements

2024 – Design

2025 – Construction

Pipe Rehabilitation