Blue Plains Prepares for a Future with More Flooding

 Sitting on the southernmost tip of Washington DC, across the river from Alexandria is the Blue Plains Advanced Wastewater Treatment Plant. Blue Plains serves not only Washington DC but also parts of Maryland and Virginia. Because of its location adjacent to the Potomac River Blue Plains is vulnerable to flooding. The facility has historically been protected from flooding by a seawall built to withstand a 1-100 year flood. However, that is no longer enough.

Blue Plains is in the middle of constructing a new seawall to protect their billions of dollars of infrastructure and treatment capabilities from storm damage. The new seawall will be a minimum of 17.2 feet high three feet higher than the level now required for a Category 3 storm or what used to be known as a 500-year flood. The seawall is expected to cost $13 million and be completed in 2021. This will help protect the facility against rising river levels and storm surges and protect the community during storms.

As a federal facility DC Water conducted required assessment of the potential impacts of climate change on its critical facilities under the 2018 Water Infrastructure Act. Blue Plains is a category III critical facility (as defined by FEMA) that currently lies within the 100-year floodplain and protected by a sea wall. EPA has a handy dandy tool to perform assess the risk and identify vulnerabilities and adaption strategies. As a major facility with a large investment along the riverfront, building a seawall to protect against flooding was deemed a better strategy rather than moving the entire facility to higher ground that DC Water did not have.

For the past decade Blue Plains has been engaged in the Clean Rivers Project an ongoing program to reduce combined sewer overflows (CSO's) into the District's waterways - the Anacostia and Potomac Rivers and Rock Creek. The Project is a massive infrastructure and support program designed to capture and clean wastewater during rainfalls before it ever reaches the rivers and when completed will cost billions of dollars. The Clean Rivers Project was conceived and agreed to under a consent order from the Environmental Protection Agency, EPA, to meet new effluent limits for total nitrogen released and better control of the system during rain storms. The Clean Rivers Project is comprised of a system of deep tunnels, sewers and diversion facilities to capture combined sewer overflows and deliver them to DC Water’s Blue Plains Advanced Wastewater Treatment Plant when the capacity is available to treat them, enhanced nitrogen removal, ENR, facilities, improved and expanded treatment of waste and upgrading the treatment of Biosolids.

Blue Plains now has Cambi thermal hydrolysis trains, four digesters, new dewatering equipment and a combined heat and power plant. The new digestor system uses thermal hydrolysis (heating to over 160 degrees under high pressure) followed by anaerobic digestors. The system produces methane gas which is captured and used to run turbines to produce power that will meet over one third of DC Water's electric demand at Blue Plains and the digestion process destroys nearly one half of the Biosolids and producing Class A Biosolids reducing the chemical treatment costs and the transportation costs to get rid of the Biosolids.