Confined Construction due to Nearby Drainage Canal
The East Manawa Drive Trail involved situating a recreational trail within a narrow corridor of right-of-way with a minimal constructible area. The corridor was located between Manawa Drive and the existing Lateral 5 concrete drainage canal serving southeast Council Bluffs and U.S. Highway 92, which is also known as Veterans Memorial Highway.
Obtaining an accurate topographical survey was critical to the project. The survey required for design purposes needed to clarify areas of concern that resulted in a reduction of trail width from 10 feet to segments of eight feet while maintaining drainage over the top of the roadway curb and meeting required trail shouldering specifications. The narrow right-of-way contained multiple underground fiber-optic and telephone facilities, overhead power poles, a water main, hydrants, traffic signage, and two storm sewer outfalls all located between the edge of highway shoulder pavement and the East Manawa Drive curb. Survey accurately located all above ground and underground utilities including depths which allowed the design to negate any additional construction costs to the city due to conflicts with the required storm sewer outfall modifications. Situating of the trail on the foreslope required weaving the trail between several obstacles while maintaining required clearances and maximum trail centerline profile grades that didn’t adversely affect the highway foreslope. To achieve the finished product, the accuracy of construction staking was paramount.
Property surveys were also required to delineate ownership between City and IDOT right-of-way and private properties. These surveys also correctly determined locations for planting approximately 100 trees along the East Manawa corridor as part of the landscaping plan.
Snyder & Associates completed all aspects of the project including coordination with the Iowa Department of Transportation for permitting, topographic and boundary surveys, construction documents, construction staking, construction observation, and construction administration.