The campaign is in conjunction with the 35th anniversary of the Environmental Protections Agency’s Clean Water Act.

‘‘This being the 35th anniversary, it opens the door for the [military and county officials] to make the public aware of small activities [they] can do on a daily basis to help prevent storm water pollution,” Montgomery County Aquatic Biologist Susan Moore said.

Montgomery County Storm Water Facility Maintenance Program Manager Amy Stevens said storm water runoff comes from rain water collected on impervious surfaces, such as roof tops, sidewalks and roads. The water collects dirt and grime on its way to the sewer drain.

‘‘One of the problems with storm water is due to our increase in impervious surfaces [and] the volume of water used,” Stevens said. ‘‘If that increase of volume is not controlled, it will scour out and destroy a stream.”

Washington Naval Facilities Engineering Command’s Environ-mental Engineer Mark Liau said many of the storm sewers in Bethesda run into creeks, which eventually lead to the Potomac River.

Stevens said the ground helps filter rain water.

Moore said the pollutants washed into the county’s natural water system have negative effects on the ecosystem.

Stevens said many pollutants are from fertilizers and pesticides, and from car oils and greases. She said pet manure also adds to runoff pollution.

‘‘Often times, [fertilizer and pesticide] instructions give you the correct application rate,” Liau said. ‘‘When it rains, any excess put on the lawn is washed into the drains, which goes into the Potomac River, which goes into the Chesapeake Bay.

‘‘When settlers first got here, the bay was clear to the bottom,” Liau said. ‘‘It’s now murky.”