V4 12 Stormwater Maintenance Manual

Inspection/Maintenance A retention/detention system should be inspected at a minimum of one time a year or after major rain events if necessary. The following is the recommended procedure to inspect system in service: 1) 2) 3) 4) 5) Locate the riser section of the retention/detention system. The riser will typically be 24” in diameter or larger. Remove the lid from the riser. Measure the sediment buildup at each riser and cleanout location. Only certified confined space entry personnel having appropriate equipment should be permitted to enter the retention/detention System. Inspect each manifold, all laterals, and outlet pipes for sediment build up, obstructions, or other problems. Obstructions should be removed at this time. If measured sediment build up is between 5% - 20% of the pipe diameter, cleaning should be considered; if sediment build up exceeds 20%, cleaning should be performed at the earliest opportunity. A thorough cleaning of the system (manifolds and laterals) shall be performed by either manual methods or by a vacuum truck. 4640 TRUEMAN BLVD. HILLIARD, OH 43026. (800) 821-6710 - www.ads-pipe.com l 3