Back River Wastewater Treatment Plant is permitted to discharge treated wastewater under state-issued permit you can review here. The state conducts inspections and data audits to ensure compliance with the permit requirements. 

In the past, checking on how wastewater treatment plants were doing was a bit like getting a report card once a year—by the time you saw a problem, it had already been happening for a long time.

Now, we use an early warning system to monitor our most advanced plants every single month. 

By tracking nutrients like nitrogen and phosphorus year-round, we can spot "red flags" before they become actual violations. Since weather or temperature can cause temporary dips in performance, we focus on three-month averages to identify real trends. If a plant is heading off-course, we send a warning letter immediately so the facility can fix the issue before the year ends.

This proactive approach has already been a success. For example, when major plants like Back River and Patapsco faced challenges, this system allowed us to step in with frequent inspections and guidance. This ensured they stayed within their legal limits and kept our waterways healthy. Read more about improvements here.

Back River has achieved a complete reversal from its 2022 performance, reaching over 90% permit compliance in 2025 while consistently meeting effluent limits and reducing nitrogen pollution by more than 60% and phosphorus by 80%.

Compliance Activities 

Inspection reports for Back River (Search site number 8449)

Discharge Monitoring Reports

Discharge Monitoring Reports User Guide

Discharge Monitoring Reports Data Dictionary
Daily E. Coli Data (Updated monthly)
University of Maryland for Environmental Science Report

Consent Decree

The following improvements are in progress or completed under a Consent Decree between the city and state: