In a letter to customers, the Westchester Joint Water Works states that tap water in the locations it supplies with water contains levels of haloacetic acid above levels deemed standard by the EPA. 

According to the Environmental Protection Agency, haloacetic acid can cause skin issues, increase the risk of birth defects and has been shown to cause cancer in mice – not humans.

The alert affects tens of thousands of families in multiple communities. According to its website, WJWW consists of the member municipalities of the Village of Mamaroneck, Town of Mamaroneck and the Town/Village of Harrison.  It also says that it supplies water on a retail basis to its member municipalities and to portions of the City of Rye and the City of New Rochelle and sells water on a wholesale basis to the Village of Larchmont and Suez Water Westchester.

Mount Pleasant found out last year that it had elevated levels of haloacetic acid and has since been working to reduce it. So far, it has not found a solution to the issue.

Haloacetic acid is caused by the interaction of chlorine and organic matter in water.

The letter states that “this is not an emergency.” It can be read in its entirety here.