On September 4, 2019, EPA issued a Clean Water Act Administrative Compliance Order to the City of Somerville, Massachusetts for its failure to meet the conditions of its municipal separate storm sewer system (MS4) general permit and for not properly operating and maintaining its sewer collection system. These violations have resulted in direct or indirect unauthorized discharges to the Mystic River in violation of the permit. EPA has ordered the City to take action to address SSO and MS4 noncompliance.