Patuxent River given D-minus

First overall health assessment faults suburban and urban growth

The result is no surprise to environmentalists who monitor the Chesapeake Bay and its river systems, said Patuxent Riverkeeper Fred Tutman, whose advocacy organization released the report in conjunction with the University of Maryland Center for Environmental Sciences.

‘‘I think the key finding is that the river is no better than anyone would expect based on other report cards for the Chesapeake Bay or other tributaries in the region,” Tutman said. ‘‘Really, nothing is looking up in terms of water quality.”

The report card’s overall grade is based on how close the river came to meeting targets for six indicators, including water clarity, dissolved oxygen levels and the presence of aquatic grasses and microorganisms.

The report, along with a similar report on the Chester River on the Eastern Shore, was funded by a $25,000 grant from the Chesapeake Bay Trust.

Bill Dennison, a UMCES professor who helped compile the report, said it was created to complement similar reports done recently on the overall health of the bay.

‘‘The purpose is to engage stakeholders in each of the regions to have a conversation on what we can do to turn these report cards around,” Dennison said.

The Patuxent, which runs through seven counties before emptying into the Chesapeake at Solomons Island, is the longest river that flows entirely in Maryland.

Tutman said many of the river’s problems stem from the growth of Columbia, Laurel, Bowie and other high-density areas, as well as from housing developments built too close to the river and the streams that feed into it.

Suburban and urban expansion adds pollution to the river primarily through increased septic system flows and runoff from roads, parking lots and other hard surfaces.

Agricultural land along the river, through the use of fertilizers and other chemicals, also contributes large levels of pollutants. Farms cause the highest levels of sediment, which prevents sunlight from penetrating the water, further harming wildlife.

The Patuxent River watershed in 2000 was 44 percent forested, 36 percent developed, 17 percent farmland and 3 percent mixed, according to modeling by the Chesapeake Bay Program cited in the report.

The main pollutants are nitrogen and phosphorous, which stimulate the growth of algal blooms in the water that choke off other life by blocking sunlight and depleting oxygen.

High levels of nitrogen and phosphorous have caused a ‘‘dead zone” in the lower Patuxent River, Dennison said. A dead zone is an area of water with oxygen levels so low that no fish or shellfish can survive in it.

While data for this report was collected from the Chesapeake Bay Program’s monitoring system, Tutman said future reports will be based on data collected by volunteers that the Patuxent Riverkeeper has recruited.

Tutman said the aim of using volunteers is to make data collection transparent and to engage residents in environmental advocacy.

About 50 people along the river have volunteered to regularly monitor water quality at sites near their homes using test kits, Tutman said. They enter their findings online.

One Upper Marlboro volunteer, 53-year-old Dave Puth, said he spends 10 to 20 minutes once every two weeks collecting data at his two local sites.

He said he joined the effort after seeing how the river has changed in the 50 years he has lived near it.

‘‘I’ve seen the amount of wildlife and the water quality go down, so at some point you have to step up to help make people aware of it,” Puth said.