According to a new report by the state’s Department of Environmental Protection, Montgomery County, along with the majority of Southeastern Pennsylvania, have among the most polluted waterways in the Keystone State, writes Frank Kummer for The Philadelphia Inquirer.

Overall, 2,398 more miles of the state’s streams have been designated as impaired over the last two years, bringing the total to 27,886 miles.

These include segments of well-known local streams or rivers, such as the Schuylkill and Delaware River.

Montgomery County ranked fourth in the region among the counties with the highest percentage of streams impaired for aquatic life, recreation, fish consumption, or drinking.

From the 852 miles assessed, 640, or 75 percent, were found to be impaired.

The main causes for stream impairment in the region include agricultural, storm-water runoff, and acid-mine drainage.

“The many thousands of miles of impaired streams, and high proportions in Southeastern Pennsylvania counties described in this report, tells us that polluted streams are still common in our neighborhoods, and we have a lot of work to reduce the pollution reaching those streams and eventually the Delaware River and its estuary,” said John Jackson, a scientist with the Stroud Water Research Center.

Read more about the findings on Montco waterways in The Philadelphia Inquirer.