Sewage & Septic Systems

Reducing Nitrogen Pollution from Sewage Treatment Plants


Largely because of pollution from excess nitrogen and phosphorus, the Chesapeake Bay and its tidal rivers are on the Clean Water Act's list of impaired waters.

Nitrogen and phosphorus pollution causes algae blooms that block sunlight to underwater grasses and remove oxygen from the water, creating "dead zones"—areas of the Bay that have too little oxygen to support a healthy ecosystem. (Get real-time data about water quality from the Maryland Department of Natural Resources). These problems degrade habitat for key plants and animals in the Bay's ecosystem, including underwater grasses, crabs, rockfish, and oysters.

The Chesapeake 2000 Agreement—signed by Pennsylvania, Maryland, Virginia, the District of Columbia, and the Environmental Protection Agency (EPA)—committed to take actions that were necessary to remove the Bay and its tidal tributaries from the impaired waters list by 2010. To accomplish this, EPA has calculated that nitrogen loads must be reduced by 110 million pounds each year from the year 2000's levels. By upgrading sewage treatment plants (STP) in the Bay watershed with nutrient removal technology (NRT), we can achieve approximately 20 percent of the necessary pollution load reductions. This is one of the most cost-effective ways to clean up the Bay.

To achieve this goal, the Chesapeake Bay Foundation (CBF) is:

  • Educating the public and elected officials about the importance of improved sewage treatment to Bay restoration.
  • Seeking funding sources to pay for upgrades.
  • Demanding that the states and EPA enforce existing laws to limit nitrogen pollution from these sources.
  • Working with a public-private partnership to establish a program using nutrient trading to reduce pollution.


CBF issued a report that offers citizens comprehensive information on how much nitrogen pollution is coming from major STPs in the Chesapeake Bay watershed. In addition, A "Lot" for Less, a report prepared for CBF by Clifford W. Randall, Ph.D., Emeritus Professor of Environmental Engineering, Virginia Tech, concludes that implementation of nitrogen removal technology could be accomplished for 50 to 60 percent less than current projected costs.


In 2004 in Maryland, CBF helped pass the Bay Restoration Fund, which established a fund to upgrade the state's 66 major sewer plants. Later, the fund also was used to upgrade on-site septic systems. Originally, each Maryland household paid $2.50 to the fund. In 2012, the Maryland General Assembly increased the fee to $5 a month.

In Virginia, over the past six years the legislature has approved more than a half-billion dollars in state funding or bond money for sewage treatment plant upgrades. As substantial as this funding has been, it remains short of what is needed by localities to meet Virginia's water quality goals. CBF continues to advocate for sufficient state assistance to local wastewater treatment plants to meet Chesapeake Bay blueprint goals for 2017 and beyond.

In 2008, CBF's Pennsylvania office and partners garnered public support for the passage of the Pennsylvania Fair Share for Clean Water Plan. This comprehensive funding package was designed to help improve local water quality and also meet Bay obligations. In total, the Plan made available $1.2 billion in grants and loans for upgrades to water and wastewater treatment plants. 


CBF has filed several legal challenges to force the EPA, along with Maryland, Virginia, and Pennsylvania, to comply with the Clean Water Act and require enforceable permit limits on nitrogen and phosphorus pollution from sewage treatment and industrial plants. CBF is currently tracking new and revised permits in Maryland, Virginia, and Pennsylvania to ensure that the states comply with this requirement.

Decades of Success: The 1970s

Even as a young organization, our work was effective and got noticed. Find out what we did.

Explore Our Timeline

Save the Bay

Founded in 1967, the Chesapeake Bay Foundation (CBF) is the largest independent conservation organization dedicated solely to saving the Bay.

Save the Bay