Completed in early 2012, the Nanofiltration Facility at the North Water Treatment Plant on Osprey Street, was a major construction step for SMRU, the last piece of equipment needed to complete the northern water quality improvement plan. Nanofiltration is a special filter processing technology very much like reverse osmosis with its series of filters which remove the hardness, color and various minerals from the water and enhance the water quality to your tap.
Prior to the nanofiltration system coming on-line, raw water from 7 surficial or shallow wells was treated through chlorination and the addition of ammonia and a corrosion inhibitor. Following this chemical injection, the water flowed through a static mixer and into the twin, 500,000 gallon storage tanks, prior to customer distribution by high service pumps.
The new nano system is a “side-stream” operation, meaning that it takes a portion of the flow from the wells just upstream of the existing chemical addition, provides membrane treatment and then blends the membrane permeate with the raw water, just upstream of the chemical addition station, prior to flowing to the ground storage tanks, ready for distribution. The finished water in the ground water storage tanks is a 50/50 blend of the membrane permeate plus the chemically dosed raw water, to arrive at finished water on an equal par with that leaving the South Plant.