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50 Elm St., Dedham, MA 02026

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Cross Connection Control Program

Cross Connection Control Program and Backflow Prevention

What is a Cross Connection, and what can I do about it?
A cross connection is a connection between a drinking water pipe and a polluted source. The pollution can come from your own home. For instance, you’re going to spray fertilizer on your lawn. You hook up your hose to the sprayer that contains the fertilizer. If the water pressure drops at the same time you turn on the hose, the fertilizer may be sucked back into the drinking water pipes through the hose. This problem can be prevented by using an attachment on your hose called a backflow-prevention device.

The Dedham-Westwood Water District recommends the installation of backflow prevention devices, such as a low-cost hose bib vacuum breaker, for all inside and outside hose connections. You can purchase this at a hardware store or plumbing supply store. This is a great way for you to help protect the water in your home as well as the drinking water system in your town! For additional information on cross connections and on the status of your water systems cross connection program, please contact Stephanie Costa at our office.

Dedham-Westwood Water District’s Cross Connection Control Program, as mandated by the Massachusetts Department of Environmental Protection, is a key element of the Water System operation. The District is committed to protecting your public water system from contamination due to backflow or backsiphonage of connections containing non-potable water.

Backpressure and cross-contamination can occur when the pressure in the equipment or a system is greater than the pressure in the drinking water system. Contamination can also occur when the pressure in the drinking water line drops due to occurrences such as main breaks and heavy water demand, causing contaminants to be drawn out from equipment and into the drinking water system.

The District’s water system is protected by the control of actual or potential cross connections through two programs:

As required by Massachusetts Drinking Water Regulations, every six months, the Customer Service team performs backflow device testing as a fee-for-service program. Devices are tested, and a report is given to the property owner. Follow-up tests are performed if the device fails the initial test. Repairs to backflow preventers are repaired by independent firms at the owner’s expense. The Dedham-Westwood Water District is responsible for reporting and managing survey and testing reports. Conditions of the systems are reported to the MassDEP.

Common Sources of Cross Connections

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 or fertilizer application. Water suppliers are required to survey all industrial, commercial and institutional and municipal facilities to ensure all cross connections are identified and eliminated or protected by an appropriate device.

Forms required for approval of Cross Connection and Backflow Preventor devices:


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