This plant was constructed in 1907, with significant upgrades in 1967 and 1973. Mill treatment plants use surface water as the source supply. In the near future, Waterworks will be supplementing the surface water supplies with a brackish groundwater supply. Each water supply reservoir is equipped with an intake structure and raw water pumping station. As water enters the intake structure, water passes through screens to remove large debris such as sticks, logs and plants.
Raw water pumps then transmit the water from the reservoir intake structure to the treatment plant.
Once water enters the treatment plant, alum, an abbreviated term for aluminum sulfate, is added as a coagulant to attract charged particles present in the water, making them larger and easier to remove in subsequent treatment processes. At Harwood s Mill, a polymer is added at this stage to make the particles stickier and even easier to remove. PAC is added for taste and odor control whereas potassium permanganate is added to oxidize iron and manganese present in the raw water. Addition of these two chemicals typically occurs during the spring and fall seasons when rainfall and subsequent surface runoff to the reservoirs is greater. After the water is chemically conditioned, water is transmitted to a clarifier for removal of larger particles through flocculation and sedimentation.