Following a review of the hydraulic modeling and water sampling results, the Iowa Department of Natural Resources (IDNR) has determined that they will not need further environmental analysis and approved the permit needed for continuation of construction of the Dubuque Flood Gate Replacement and Pump Station Project at the 16th Street Detention Basin.

The project had been paused approximately three months while additional environmental studies were conducted to determine if contaminants from a nearby fertilizer spill in 2020 would be drawn towards the project site during dewatering operations as part of the construction of the pumping facility.

The IDNR reviewed data recently collected from water sampling and modeling on the flow of water and possible contamination from the spill site toward the detention basin and the dewatering wells that will be used during the project.  Following that review, the IDNR determined additional analysis beyond this review phase is not necessary and the agency approved the project’s application for 10 dewatering wells to facilitate construction. Work on the site is expected to resume soon. Related lane closures/detours on Kerper Blvd. will be reinstated when needed to facilitate work at the site.

The $28.2 million project is the next major phase of the Bee Branch Watershed Flood Mitigation Project. It involves the construction of a new stormwater pumping station on Kerper Blvd. and the decommissioning of the existing pump station system installed as part of the John C. Culver Floodwall/Levee system. The new facility will include a new flood gate, four new 100,000 gallon-per-minute pumps (double the pumping capacity of the existing facility), new electrical service, and the installation of back-up generators. The improvements will greatly enhance the system that conveys stormwater from the Bee Branch Watershed to the Mississippi River and protects over 1,300 properties from flooding during high river levels. The project also adds additional resiliency options as rainstorms increase in both rainfall and intensity. It builds upon the flood protection established through earlier phases of the Bee Branch Project, which currently safeguards against storms as severe as a 500-year event.