Where discharges of treated effluent is made directly into a high quality watercourse, CAP Technology usually install a rotary drum filter fitted with a 10-micron mesh. This would guarantee that all effluent contains less than 30mg/l suspended solids.
This system is an alternative to conventional sand filtration. It requires a low differential head of effluent and uses significantly less backwash water. The backwash water is drawn from an internal reservoir and therefore does not require excessive retention of filtered effluent.