Title
Request Authorization to Amend Intergovernmental Agreement with Flood Control District of Maricopa County and City of Scottsdale for Rawhide Wash Flood Hazard Mitigation Project (Ordinance S-46261)
Description
Request to authorize the City Manager, or his designee, to amend an Intergovernmental Agreement (IGA) with the Flood Control District of Maricopa County (FCDMC) and the City of Scottsdale for the Rawhide Wash Project. The request is to amend the original IGA for the City of Scottsdale to undertake and acquire all rights of way, temporary construction easements, and permanent easements for the proposed project. The current IGA includes the design phase, channel rights-of-way, and utility relocations. Further request authorization for the City Treasurer to accept, and the City Controller to disburse, all funds related to this item. Currently there are no changes to the funding allocations set in the original IGA.
Report
Summary
The Rawhide Wash Flood Hazard Mitigation project is defined as the conveyance alternative presented in the Pinnacle Peak West Area Drainage Master Study. The northern limit of the infrastructure is approximately the Rawhide Wash alluvial fan apex located north of Happy Valley Road and the southern limit is the bridge crossing at Pinnacle Peak Road east of Scottsdale Road. The project improvements will include construction of new floodwalls and levees and re-construction of existing floodwalls and levees. The project will also include submittal of an application for a Federal Emergency Management Agency (FEMA) Letter of Map Revision to revise the apex flow discharge and the re-delineation of the floodplain limits downstream of Scottsdale Road within City of Phoenix jurisdiction upon completion of this construction project. Floodplain re-delineation within City of Phoenix jurisdiction will be based on existing condition drainage infrastructure, development activities, and topography that will reduce the existing Special Flood Hazard Area Zone "AO." After completion of the proposed project, 1,933 acres of land will no longer be designated in a FEMA delineated floodplain. Approximately 80 percent of this land (1,531 acres) is within the City of Phoenix jurisdiction, and the remaining 20 percent (402 acres) is within the City of Scottsdale and unincorporated County areas. The project cost share analysis was developed based on flood damage reduction, flood insurance savings, reduced cost of fill for future development and the elimination of redundant infrastructure costs. This resulted in a cost share of 50 percent FCDMC, 40 percent City of Phoenix, and 10 percent City of Scottsdale.
FCDMC has requested the City of Scottsdale be the lead agency for acquisition of all rights of way, temporary construction easements, and permanent easements for the proposed project.
Financial Impact
Currently there are no changes to the funding allocations set in the original IGA. The estimated project design cost is $2 million. Of this amount, the City's cost share is estimated to be $800,000, with the remainder covered by FCDMC and the City of Scottsdale in the allocated cost shares noted above. Funds for the City's cost share are available in the Street Transportation Department's Capital Improvement Program budget.
Concurrence/Previous Council Action
- On July 6, 2017, Council approved the request to apply for FCDMC funds for Flood Control Projects under the Capital Improvement Project Prioritization Process (CIPPP).
- The request to enter into the original IGA with the FCDMC and the City of Scottsdale was recommended for approval by the Water, Wastewater, Infrastructure and Sustainability Subcommittee at its Nov. 7, 2018 meeting, by a vote of 4-0.
- Approval to enter into the original IGA for this project was granted by City Council on Dec. 12, 2018 (Ordinance S-45224).
- On Nov. 6, 2019, the request to amend the original IGA with the FCDMC and the City of Scottsdale was recommended for approval by the Transportation, Infrastructure, and Innovation Subcommittee meeting, by a vote of 4-0.
Location
The northern limit of the Project is generally the Rawhide Wash alluvial fan apex located north of Happy Valley Road and the southern limit is the bridge crossing at Pinnacle Peak Road.
Council District: 2 and Out of City
Department
Responsible Department
This item is submitted by Deputy City Managers Karen Peters and Mario Paniagua, and the Street Transportation and Public Works departments.