CBF Calls for Safety and Process Improvements at Back River and Patapsco Wastewater Treatment Plants After Fire and Explosion

The Chesapeake Bay Foundation (CBF) is urging Baltimore city and Maryland officials to act quickly to review and fix problems related to biosolids processing at the two largest wastewater treatment plants in the state after an explosion and fire Wednesday damaged a building at the Back River Wastewater Treatment Plant in Dundalk. 

Due to the seriousness of the issue and to stop the spread of misinformation through conspiracy theories about it online, CBF is calling on state officials to provide as much information as possible about the cause of the fire, how it will impact the plant’s overall operations, how public and worker safety will be protected, and how the plant will be fixed. 

The fire-damaged building was used to dry out sludge material separated from wastewater to later be used as fertilizer.  

Problems related to biosolids, or sludge, processing were first identified in the spring of 2021 after Blue Water Baltimore discovered excessive pollution discharges at the Back River plant and the Patapsco Wastewater Treatment Plants due to cascading operations and maintenance failures at the plants. Those failures led to sludge clogging up important equipment such as centrifuges and primary settling tanks designed to separate solids from wastewater during the treatment process, according to state-issued reports.  

At Back River, the state brought in Maryland Environmental Service (MES) to oversee fixes at the plant in March 2022. MES issued a report in July that directly linked issues with the third-party contractor Synagro’s struggles to process sludge material to the facility’s problems with filtering pollution from wastewater before it’s pumped into Back River. MES recommended sludge issues at the plant be fixed within six months, however it’s not clear if these fixes have been made or if they’re working. 

The most recent publicly available inspection report from Back River, released by MDE in January, found “crucial equipment maintenance and repairs are not being performed at Back River [Wastewater Treatment Plant]” and that officials have “failed to provide enough qualified staff to adequately operate and maintain the [plant].” 

At the Patapsco plant, the latest inspection report from Nov. 2 also details significant problems related to biosolids treatment and processing. Potentially flammable hydrocarbons present in the Patapsco plant’s sludge have been preventing Synagro from pelletizing, or drying out, the sludge at that plant, according to the report. The report noted that "process equipment issues have been outstanding for months and many for over one year” at the Patapsco plant. 

These ongoing maintenance and operations failures at Maryland’s largest wastewater plants are causing excessive amounts of pollutants to reach Chesapeake Bay. The Patapsco plant from Jan. to Nov. 2022 exceeded its annual permitted limit for nitrogen pollution by about 1.4 million pounds—nearly triple its permit limit, according to the Jan. inspection report. Phosphorus discharges from the plant exceeded the plant’s annual permitted limits by about 130,000 pounds—more than triple the limit. Similar statistics were not available in the state’s Back River inspection reports, but last year the Chesapeake Bay Program reported more than 2.5 million pounds of excess nitrogen reached the Chesapeake Bay due to operations failures at the Back River and Patapsco wastewater plants in 2021.  

The increases in nitrogen and phosphorus loads from these plants are risking Maryland’s ability to meet its Bay restoration commitments. Maryland’s Bay cleanup plan depends on significant pollution reductions from wastewater plants to meet agreed-upon clean water requirements.  

CBF’s Maryland Senior Scientist Doug Myers issued this statement: 

“It’s inexcusable that nearly two years after the litany of operations and maintenance problems were discovered at the Back River and Patapsco wastewater treatment plants that many of those problems still exist and have now led to serious questions about public and worker safety at the plants. It’s imperative that immediate progress be made to fix the sludge processing problems at both plants. The city must also hire more workers and properly train them on how to run these complex plants to ensure the two plants are not polluting local waterways and the Chesapeake Bay. 

“These are two of the most significant pieces of public infrastructure in the state and decisive leadership is sorely needed to bring them back to basic operating standards. Until the plants are operating properly, water quality in Back River, Patapsco River, and the Chesapeake Bay is threatened. The public deserves transparency and action to fix these problems and protect clean water.”

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A.J. Metcalf

Former Maryland Media & Communications Coordinator, CBF

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