A citizen Clean Water Act lawsuit was filed against Kiewit Corp. by the environmental group Waste Action Project, accusing the construction company of violating its environmental permits. The lawsuit, filed in Washington federal court on Thursday, claims Kiewit failed to prevent polluted stormwater from its Seattle marine yard from flowing into the Duwamish River and Elliott Bay.

According to the complaint, Kiewit exceeded the pollutant levels permitted under its stormwater runoff permits at the company’s four-acre facility next to the river. The environmental group also accuses Kiewit of neglecting mandated monitoring and reporting duties.

The lawsuit states that these alleged violations have hindered efforts to clean up the Duwamish River, which has been contaminated by decades of industrial pollution and runoff. The group claims that Kiewit’s discharges contribute to the polluted conditions of the West Waterway of the Duwamish, an area listed on the state’s impaired water bodies list.

In a similar action in May 2023, Waste Action Project sued the city of Seattle for discharging tainted stormwater runoff from a waste transfer station into Lake Union. A settlement approved in February included a $70,000 payment by the city to fund a waterfront park and commitments to enhanced runoff monitoring.

Kiewit Corp., along with its subsidiaries, Kiewit Infrastructure West Co. and Kiewit Infrastructure Corp., are accused of violating the terms of their National Pollutant Discharge Elimination System (NPDES) permit, administered by the state Department of Ecology.

The environmental group seeks an injunction to stop Kiewit from operating in violation of its permit and the Clean Water Act. They also demand access to compliance reports submitted to the Department of Ecology and seek civil penalties of $66,712 per day for each violation of the Clean Water Act.

In response, Kiewit stated that the Seattle facility's permit is complex but emphasized its commitment to meeting environmental standards. The company reaffirmed its dedication to compliance with all environmental regulations and its role as a responsible corporate entity.

Waste Action Project is represented by Marc Zemel and Evelyn Mailander of Smith & Lowney PLLC.

The case is filed under Waste Action Project v. Kiewit Corporation, case number 2:25-cv-00056, in the U.S. District Court for the Western District of Washington.