Rural to Urban Roadway Reconstruction
Significant growth in north Ankeny prompted the need for increased traffic capacity and safety between N Ankeny Boulevard and NE Delaware Avenue. To achieve these goals, it was determined the road would need to be reconstructed from a two-lane rural roadway to a four-lane urban boulevard with left turn lanes. Major components included:
- Reconstruction of three intersections
- Disconnecting one intersection from NE 36th Street and replacing it with a hammerhead configuration
- The addition of a traffic signal at the intersection of NE 36th Street and NE Trilein Drive
- Widening the existing bridge over Fourmile Creek
Due to the scope of work, construction was split into two projects to be constructed over two construction seasons. Phase 1 bridge widening occurred with the street open to traffic. During phase 2, full road reconstruction closed the road to all traffic except for local traffic with a detour route in place. This greatly improved bid prices and allowed construction to occur in one construction season without a need for temporary pavement.
Coordination with six franchise utility companies began early in the design phase, which allowed all conflicts to be relocated prior to construction. The design minimized impacts outside the existing right-of-way and temporary easements needs were minimal throughout the 4,450-foot long project corridor.
Stormwater Treatment Upstream from Fourmile Creek
A highlight of the finished project is a stormwater wetland and water quality basin built on City property south of the Woodland Reserve Greenway & Outdoor Education Center. The wetland was installed upstream from Fourmile Creek to treat storm sewer outlet water before it enters the Creek. The City of Ankeny plans to install a grass trail open to the public along the wetland area with signs to explain the stormwater treatment process. Other project features include landscaping, a new storm sewer and water main, street lighting, and sidewalks.
As the design engineer for the project, Snyder & Associates provided transportation, civil, traffic, and structural engineering. Additional services included landscape architecture, environmental, survey, construction administration and observation.