An In‐House Approach to Cross‐Connection Control at Air and Blowoff Valves

Key Takeaways Air and blowoff valves are essential for operating, draining, flushing, and filling drinking water transmission systems, but they can be a source of cross‐connection. The San Francisco Public Utilities Commission conducted site assessments for cross‐connection hazards in approximately 250 miles of transmission pipelines, with more than 1,300 air and blowoff valve appurtenances. Benefits of this in‐house project include enhanced regulatory compliance, public health protection, asset management, cost savings, and safety improvements.