Who maintains the Highway Runoff Manual (HRM)?
The Headquarters Environmental Services Office Stormwater and Watersheds Program and Headquarters Hydraulics Section are jointly responsible for revision and implementation oversight of the manual. The manual’s upkeep uses a technical team made up of water quality, stormwater, and erosion control specialists; designers; hydrologists; geotechnical and hydraulic engineers; landscape architects; and maintenance staff. The technical team also includes several county representatives, and benefits from a close working relationship with Washington State Department of Ecology staff and contributions by consultants and outside reviewers.
