The $7.5 million project for the Lake Oswego-Tigard Water Partnership included construction of a new 3.5MG prestressed concrete dome roof drinking water reservoir with new inlet, outlet piping and control valves and mixing manifold. Extensive sitework involved new cast-in-place vaults and precast vaults. Careful logistical coordination by Ward-Henshaw resulted in a smooth connection to the existing piping configurations. Modifications to the existing reservoir included boring new inlet piping for the new mixing manifold and new control valves. New stormwater drainage piping, stormwater detention basin, and overflow detention basin were carefully configured on the challenging steep and spatially tight site.