Frequently Asked Questions

The Town of Burlington’s drinking water system consists of a surface water treatment plant (Mill Pond) and a water supply connection to the Massachusetts Water Resources Authority (MWRA). The Mill Pond Water Treatment Plant treats water from the Mill Pond reservoir that fills by drawing water from the Shawsheen River in Billerica. The Mill Pond Treatment Plant has the capacity to treat up to 2.5 million gallons of water per day. The current hydraulic capacity of the MWRA connection allows for approximately an additional 2.5 MGD. Phase 2B of the MWRA pipe construction, currently underway and expected to be complete by end of 2026, is expected to increase the max capacity to ~6 MGD.

Cross-connections that contaminate drinking water distribution lines are a major concern. A cross-connection is formed at any point where a drinking water line connects to equipment (boilers), systems containing chemicals (air conditioning systems, fire sprinkler systems, irrigation systems), or water sources of questionable quality. Cross-connection contamination can occur when the pressure in the equipment or system is greater than the pressure inside the drinking water line (backpressure). Contamination can also occur when the pressure in the drinking water line drops due to fairly routine occurrences (main breaks, heavy water demand), causing contaminants to be sucked out from the equipment and into the drinking water line (backsiphonage).

Outside water taps and garden hoses tend to be the most common sources of cross-connection contamination at home. The garden hose creates a hazard when submerged in a swimming pool or when attached to a chemical sprayer for weed killing. Garden hoses that are left lying on the ground may be contaminated by fertilizers, cesspools, or garden chemicals. Improperly installed valves in your toilet could also be a source of cross-connection contamination. Community water supplies are continuously jeopardized by cross-connections unless appropriate valves, known as backflow prevention devices, are installed and maintained. We have surveyed industrial, commercial, and institutional facilities in the service area to make sure that potential cross-connections are identified and eliminated or protected by a backflow preventer. We also inspect and test backflow preventers to make sure that they provide maximum protection.

For more information on backflow prevention, contact the Safe Drinking Water Hotline at 800-426-4791.

In 2024 we analyzed 4 samples for sodium. The range of detection was 33.5-91.4 mg/l. The 33.5 mg/l sample would be considered Very Low Sodium by the FDA at about 8 mg/l per 8 ounce glass of water while the highest detection of 91.4 mg/l would be about 22 mg/l per 8 ounce glass of water. Sodium in drinking water contributes only a small fraction of a person's daily intake estimated at less than 5%.