BALTIMORE — Environmental groups are calling for tighter laws to prevent stormwater runoff pollution at Maryland industrial sites.

The Center for Progressive Reform and the Environmental Integrity Project on Thursday cited state records showing more than a third of the industrial facilities required to report results of runoff pollution testing to the state are discharging toxic materials beyond acceptable levels.

The two groups examined U.S. Environmental Protection Agency and Maryland records for 180 industrial sites that reported monitoring results from January 2014 to March 2017. The review found 36 percent of them released stormwater with excessive levels of pollutants.

The groups are calling for changes to the Maryland Department of the Environment’s industrial stormwater general permit, which is up for renewal next year. Changes would include stronger monitoring, reporting and public disclosure.