The City of Phoenix accepted the Maryvale Area Drainage Master Plan (ADMP) as the hydrological basis for future drainage improvements within the ADMP watershed. A Design Concept Report was completed by Phoenix for the 26th Avenue and Verde Lane Basin Project, a recommended component of the ADMP. The project concept included a basin that would provide a retention volume for the 100-year, 24-hour storm and associated storm drains along 25th and 26th drives. The basin would provide a positive outfall location for storm water, thereby precluding ponding from occurring within the streets and residential areas. The new basin would drain into the existing 27th Avenue storm drain system after the peak flows had passed. Phoenix was the lead agency for all design and construction-related tasks on this project.