Water Quality and Assessment

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Overall Water Quality Grade: Fail

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To arrive at the overall grade for water quality in the Anacostia River, the Anacostia Watershed Society (AWS) first evaluates and grades each of three sections of the 9-mile tidal river for the key indicators of Dissolved Oxygen, Fecal Bacteria, Water Clarity and Chlorophyll a. The three sections are the Maryland portion of the Anacostia (MD Anacostia), the upper half of the Anacostia in Washington, DC above the East Capitol Street Bridge (Upper DC Anacostia), and the lower portion in the District (Lower DC Anacostia).

The good news for the 2015 Report Card is that each of the three river segments have registered important progress for the presence of Chlorophyll a and the portions of the river in the District are showing near acceptable levels of fecal bacteria. The bad news is that these gains are not nearly enough to result in the substantial improvement of water quality in any section, or overall. With each section continuing to earn a failing grade, our overall assessment of water quality in the Anacostia River for data available and evaluated in 2015 is an F.

Anacostia River Section Map

Comparison to Last Year

Due to the many factors that affect water quality, there are limitations to the annual comparison of water quality data. For example, more intense and frequent precipitation patterns generally make the water quality worse. More rain results in more sewer overflows and an increase in polluted runoff from streets and parking lots. So the comparison of indicators for wet and dry years can mask the underlying conditions. Long term trends are generally more helpful for understanding the river and changes in water quality than year-to-year comparisons.

These effects appear at play here for dissolved oxygen (DO). Intense rain events during the grading period resulted in regular sewage and runoff discharges to the lower river from the District’s Combined Sewer Overflow (CSO) system (see Precipitation Pattern for detail). CSO overflows discharge a lot of organic matter that will later decompose, consuming oxygen in the water. As a result, dissolved oxygen values were very low in the District portion of the river. The faster flowing, more turbulent, Maryland streams carry more DO, enough that Maryland’s tidal river had enough dissolved oxygen to earn a C- for the period. In contrast, the tidal river in Maryland has higher readings of fecal bacteria than the lower portions in the District due in part to the presence of more wildlife feces upriver. Potomac River water that enters the lower Anacostia as part of the daily tide cycle also has a stronger dilution effect in the lower river which could be a factor here.

Despite the more frequent and intense rainfall events that brought more sediment to the river, water clarity improved slightly from the previous year. The trend of clearer water was also seen in the return of submerged aquatic vegetation (SAV). SAV is back -- in small amounts -- for the first time since it disappeared from the Anacostia in 2003.

The improvement in chlorophyll a is another indicator that the water is becoming clearer. Some of this may be a result of earlier improvements to the CSO system that have reduced the number of smaller and more frequent releases to the river resulting in more of the dirtier “first flush” runoff from the District being diverted to the Blue Plains Plant for treatment. The reduction of nutrient inputs to the river from these system upgrades (forty percent improvement to date) may be an important factor in the improvement of chlorophyll a and water clarity.

While there has been substantial progress in the study and assessment of legacy toxics in and along the river, notably a start to the first comprehensive study of toxic river sediments, and the establishment of a coordinating council of public officials and experts by the mayor of Washington, DC, little actual cleanup has yet to occur. Until there is a reduction in the presence of toxic substances in and along the river that results in an improvement in water quality, this grade will remain low.

Progress on trash reduction has been slow, but growing. Past efforts to install trash traps in the District and charge fees on plastic bags in DC and Montgomery County are notable. Stepped up efforts by local jurisdictions to reach goals set in trash reduction plans required by federal law (due to the extreme nature of the problem here) should soon produce more substantial results. This includes new laws to prohibit the use of plastic foam (a.k.a. Styrofoam) as food and beverage containers (effective January 1, 2016 in the District and Montgomery County, and July 1, 2016 in Prince George’s County). The proliferation of beverage containers in river trash is a major problem yet to be addressed.

Overall Effort and Commitment Grade: C+

While water quality in the river is still failing, there has been real improvement in the overall effort and commitment of area jurisdictions for the work necessary to clean the river. We see more strong, committed leadership across the watershed than ever before. And we have seen the passage of important policies to reduce pollution at its source. New funding is in place to support the substantial expansion of efforts to reduce polluted runoff by local jurisdictions. A unique public private partnership is taking hold in Prince George’s County with the intention to rapidly accelerate the use of green solutions and create local jobs -- to install and maintain rain gardens, pervious pavement, and green roofs -- to tame the ravages of polluted runoff from thousands of acres of untreated parking lots, pavement, and rooftops.

In addition to the extensive mapping and study of toxic hotspots along the river that will be used to plan the cleanup of numerous individual sites, agency officials and community leaders have been convened by the District to improve and support a comprehensive cleanup plan of contaminated river sediments.

While these many initiatives have great promise, additional efforts are required to reduce river trash, establish “river friendly” development policies, fully identify upstream sources of toxic pollution and their treatment, and restore headwaters streams damaged by intense runoff. The uneven nature of state, federal and private sector efforts must be substantially improved and accelerated or a whole new generation will be deprived of their right to grow up along a clean and healthy river, with fish safe to eat and waters fit for swimming.

But When?

The Anacostia Watershed Society is committed to collaborating with any and all to provide the residents and visitors to the Nation’s Capital a healthy Anacostia River by 2025. Our future evaluations and report cards will show just how well our public and private institutions are performing the work necessary for these waters to meet the meaningful and understandable standard of fishable and swimmable that became federal law when the Clean Water Act was passed here in the District 43 years ago, in this very watershed.

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