The City of Oklahoma City desired to improve the existing storm sewer system in the vicinity of SW 25th Street and Walker Avenue, north to the Oklahoma River. The construction funding was primarily from CDBG-DR that will be allocated over the project’s two phases.

The existing storm sewer system experienced frequent backups and flooding that impacted residential structures, businesses and severely limited travel along the city streets within the project area.

The Cabbiness design team evaluated three design alternatives:

1. Replacement of the existing storm sewer piping and inlets in the same location, with upsized inlets and piping;

2. Replace the existing inlets and utilize the existing storm sewer piping along with a parallel storm sewer system; 

3. Design a new inlet and storm sewer piping system in topography sump locations to alleviate flooding while utilizing as much of the existing system in place.

After evaluations, replacement and upsizing was the ultimate solution realized. Additional steps taken for this project included detailed hydrologic and hydraulic analysis, survey and mapping, utility research, geotechnical engineering and the development of a construction sequencing plan.