IMEG provided civil engineering and landscape architecture services for a parking lot expansion at Transwestern’s site in Arden Hills, Minnesota. The project involved adding 48 spaces to an existing parking lot. This addition of impervious surface necessitated on-site stormwater detention and infiltration. The main design challenge was to incorporate the necessary improvements with the reconfiguration of the existing parking lot.

IMEG designed two small rain garden type detention areas that delay and treat urban runoff from the parking lots prior to discharge into the city’s stormwater system.

When selecting vegetation for the north rain garden, IMEG’s landscape architect focused on maintaining sight lines for turning maneuvers at the corner of Dunlap Street and Grey Fox Road. The south rain garden was designed to be constructed within the median of the existing parking lot. The design for both detention areas uses naturalized vegetation that tolerates wet conditions after storm events.