The 11800-DH has flow-controlled weirs with adjustable flow rate capabilities. The standard flow rate is 3 cubic meters per minute per meter of weir. The 11800-DH has 0.5 meters of total weir, and therefore is normally operated at a flow rate 1.4 m3/min, 370 gal/ min. Maximin flow rate is 500gpm. The 11800-DH excludes solid during the aeration cycle. Installation options include an articulating pipe swing arm or flexible hose deployment. The system can be gravity drained or pumped. Deployment is based on site-specific conditions.