LYNDEN, Wash. -- Lynden and Birch Bay will be required to follow new rules to control stormwater pollution next year.

A new stormwater permit from the State Department of Ecology will require urban areas like Lynden and Birch Bay to manage water pollution with a process called "low impact development," which uses vegetation and soil to naturally filter rainwater.

This keeps water from running over paved surfaces and carrying pollution into lakes, rivers and Puget Sound.

Sandy Howard with Ecology says the new rules are required by the Federal Clean Water Act.



She says stormwater runoff pollution from urban areas is the biggest threat to Washington's waters.

The new stormwater permits were issued Wednesday and will take effect in August 2013.

Ecology will provide training and funding to help local governments comply with the new rules.