Trinidad & Tobago Water & Sewerage Authority, Trinidad

Richmond Water Treatment Plant; Capacity: 5.0 MLD Flow

The old water treatment plant at Richmond consisted of a filtration system alone. Since the raw water source is a river, the plant use to be shut down when the raw water characteristics changed, usually during the rainy seasons. To overcome this problem and to make the treatment facility more useful, WASA selected UEM from amongst the various local and intentional companies to design and build a new treatment facility, which would be able to sustain shock turbidity loads up to 1000 NTU.

The treatment system was designed and installed by UEM on turn-key basis. It incorporates new intake works, Flash mixers, Flocculators, Lamella Clarifiers, a Dual media Gravity Filtration system, an automatic chemical (Lime, Alum, Poly-electrolyte) dosing facility, a chlorine dosing system, and a chemical sludge recovery system.

The Richmond water treatment plant is designed for completely automatic operation. Plant operations like filter backwashing, chemical dosing, raw water and treated water pumping, sludge blow down from the clarifiers etc. is controlled by the PLC based on the data retrieved from various on line instruments through the SCADA system.

The new facility was commissioned in November 2000 and has been consistently producing treated water with <1 NTU turbidity under varying raw water characteristics.