Renton stormwater facility earns ACEC-WA gold award for innovation

The City of Renton and contractor Otak Inc. have received the Gold Award for Uniqueness and/or Innovative Application of New or Existing Techniques from the American Council of Engineering Companies of Washington for the Monroe Avenue Stormwater Facility.

Completed in January 2025, the facility is the largest stormwater infiltration system in Western Washington. Located on Monroe Avenue across from the Jimi Hendrix Memorial, the three-acre site captures runoff from 260 acres of the Renton Highlands.

The system routes stormwater through multiple treatment stages to remove debris, pollutants and fine sediments before allowing the treated water to infiltrate into the ground, recharge aquifers and feed the Cedar River. The project eliminated reliance on a former gravel pit to manage heavy rainfall events and was completed four months ahead of schedule and under budget.

The Washington State Department of Ecology funded 85% of construction costs through stormwater quality grants. City officials say the project represents a significant advancement in managing runoff and protecting downstream waterways in a growing urban area.