Mission & Molter Roundabout

Liberty Lake, WA




Civil Engineering

Land Surveying

Landscape Architecture


New roundabout replaces four-way stop

Project uses bio-infiltration facilities to manage stormwater

Designed to WSDOT standards

New roundabout eases traffic congestion in expanding area.

AHBL’s civil engineers, land surveyors and landscape architects worked with the City of Liberty Lake to design a new roundabout at the intersection of Mission Avenue and Molter Road. This new roundabout replaces a four-way stop, and will ease congestion when a new employer opens their facility to accommodate 600 employees. The roundabout is partially funded by a Washington Transportation Improvement Board (TIB) grant.

The project was designed to WSDOT standards and includes a roundabout with four “legs,” landscape splitter islands, curbs, irrigation and lighting within the ROW. To save cost, improvements updated and renovated the existing stormwater facilities. New bio-infiltration facilities treat stormwater in areas where pavement was reduced, and where the roundabout expanded paved areas, stormwater will be re-directed to new and updated bio-infiltration ponds. Sustainable plantings provide seasonal interest and require low maintenance.