When redevelopment of a major downtown Evansville site included the expansion of an existing parking lot, the local water and sewer utility requested that the owner pursue adding stormwater quality and quantity management capabilities as part of the project. EMH&T completed the design of this first private site development project approved by the City for supplemental funding. The project was based on the inclusion of green infrastructure designed to remove up to the first two inches of stormwater runoff from the combined sewer system. Known as Professionals Plaza, this project is located on property which was previously the headquarters for the Evansville-Vanderburgh School District and has been redeveloped as a commercial property. EMH&T provided site/civil development design services to expand the existing parking lot to provide a drive-thru for a bank tenant, and added an exit from the site onto an adjoining street. The project included 125,000 gallons of underground storage as well as permeable paver and traditional asphalt parking surfaces. The underground storage was a detention area placed over an 8-foot x 180-foot infiltration trench about 10-feet deep to provide for the stormwater infiltration. The project disconnected 2.3 acres of drainage from the combined sewer system, thus eliminating more than two million gallons a year of treatment of stormwater at the waste water treatment plant.