For more than 145 years, Lake Massabesic has served as the water supply for Manchester and portions of six surrounding communities. In order to satisfy stringent state and federal drinking water regulations, the lake water is purified at Manchester's Water Treatment Plant. The facility was completed in 1974 and has since been routinely updated with state-of-the-art equipment to improve quality control and operational efficiency and was significantly upgraded in 2006. Located adjacent to Lake Massabesic, the plant treats all of the City's water before it is pumped into a 500+ mile piping network for distribution to homes and industries.
The plant has a maximum hydraulic capacity of 50 million gallons per day and presently delivers in excess of 17 million gallons per day to approximately 160,000 consumers in the greater Manchester area. Manchester's modern treatment facility has been designed to treat a wide range of water quality problems to ensure that the customer receives the best possible drinking water.
Knowing that Lake Massabesic would not be sufficient to meet the demand of a large growing city indefinitely, Manchester Water Works has remained focused on short and long-term development trends, their impact on water demand, and the inevitable need for additional supply. Water resource studies have identified and evaluated the Merrimack River as a future supply for Manchester estimating that additional source water would be needed between 2010 and 2020. Following research and discussion with hydrogeologists specializing in large groundwater withdrawals, the concept of riverbank filtration (RBF) was brought forward as a potential means to meet future water quantity and quality goals while minimizing or eliminating the need for pretreatment. Further investigation into the feasibility of RBF led to the design and construction of a radial collector well adjacent to the Merrimack River in Hooksett that is currently being permitted for withdrawal of just over 7 million gallons per day. A new treatment facility near the well will purify the water to match or exceed the water quality from the Lake Massabesic plant. The new treatment facility is estimated to be complete and serving our customers by 2020.