Ankeny targets Rock Creek for regional detention study

Ankeny targets Rock Creek for regional detention studyAnkeny’s October 5 council agenda included a proposed $60,000 Bolton & Menk study of regional stormwater infrastructure in the Rock Creek corridor. The work would assess detention, wetlands, floodplain storage and nature-based practices across a future-growth area.

The proposed Bolton & Menk agreement caps fees for the Rock Creek Greenbelt and Regional Detention Feasibility Study at $60,000.

The study area is bounded by NW 36th Street, NW Irvinedale Drive and Ankeny’s 2040 future corporate boundaries.

The scope includes a planning-level watershed assessment and identification of potential regional detention basins, stormwater wetlands, floodplain-storage enhancements and water-quality treatment opportunities.

The study is expected to take about six months and is included in Ankeny’s FY2027 operating budget.

Ankeny is proposing to examine whether the Rock Creek corridor can accommodate a coordinated regional stormwater system rather than fragmented facilities tied to individual development sites. The city council’s October 5 consent agenda included a professional-services agreement with Bolton & Menk for the Rock Creek Greenbelt and Regional Detention Feasibility Study, with fees not to exceed $60,000. The proposed work covers an area bounded by NW 36th Street to the south, NW Irvinedale Drive to the east, and the city’s Comprehensive Plan 2040 future corporate boundaries to the north and west. At planning level, the consultant would assess watershed conditions using available topographic, drainage and development information. Its remit includes identifying potential regional detention basins, stormwater wetlands, floodplain-storage enhancements, multipurpose facilities integrated with open space, and nature-based stormwater practices. The scope calls for identifying prospective practice locations and the developable areas they could serve, as well as order-of-magnitude storage estimates rather than detailed design. The study would also map existing drainage patterns, prairie potholes, natural resources and land ownership, identifying areas where preservation or acquisition could provide value for stormwater management. Environmental, cultural-resource and land-acquisition desktop reviews are included. City staff said the work is expected to take approximately six months. The final plan is intended to set out planning-level cost estimates, priorities, phasing and potential funding opportunities. Stakeholder meetings and a wider public-engagement component are also proposed. The Rock Creek assignment forms part of Ankeny’s FY2027 operating budget. The council packet did not provide construction costs or commit the city to building any of the prospective detention facilities identified through the feasibility work.