Littleton’s drinking water comes from shallow sand and gravel deposits located within the Beaver Brook and Bennett’s Brook watersheds. Four groundwater production wells withdraw over one and a half million gallons per day of drinking water. The sand and gravel act as an underground reservoir, which is continually replenished by rainfall and snowmelt.
In 1998 the Spectacle Pond Treatment Plant began operation to remove iron and manganese from the water supply well located near the pond. The treatment process utilizes ozone to oxide the water causes the iron and manganese to form solid precipitates that are then removed by fine pore filters (ultrafiltration). As an added benefit, these filters prevent microorganisms from entering the distribution system.
In 2014 the Beaver Brook Treatment Plant was brought online, a state of the art Hungerford & Terry GreensandPlusTM filter treatment plant. The use of Greensand plus filter media will remove the elevated levels of iron and manganese, two minerals that cause nuisance issues including rust, staining of plumbing fixtures and laundry, as well as discoloration of the drinking water.
Treatment Methods Used in Littleton’s Drinking Water
|Sodium Hypochlorite||Provides disinfection against germs and bacteria.|
|Potassium Hydroxide||Provides pH adjustment. Works as a corrosion inhibitor. Protects distribution system and customer’s home plumbing system from corrosion.|
|Works as a sequestering agent to suspend iron and manganese particles. Also a corrosion inhibitor to stabilize metal surfaces of iron and copper pipelines.|
|Ozone Gas||Strong oxidant that pulls iron and manganese out of water|
|Pressure Filtration||Utilizes sodium hypochlorite to pre-oxidize iron and manganese and then remove it through filtration and absorption.|
|Koch Membrane Filtering||Removes suspended solids and other large molecular weight materials from water.|