The Metropolitan St. Louis Sewer District (MSD) embarked on a $5-7 Billion program of infrastructure/capital improvements to protect public health and comply with a federal consent decree to address combined and sanitary sewer overflows. MSD provides wastewater and stormwater operations for 1.4 million people in 524 square miles of the City of St. Louis and St. Louis County. MSD operates and maintains approximately 2,980 miles of stormwater, 4,750 miles of sanitary, and 1,920 miles of combined sewers; 194 sanitary and 66 combined sewer pump stations; and nine wastewater treatment facilities typically treating a total of 350 million gallons a day (MGD).
MSD had historically monitored the water quality information of streams and rivers within its service area. Stream discharge and water quality data have been collected at numerous locations since 1996 under a cooperative agreement between MSD and the U.S. Geological Survey (USGS) and MSD conducted its own in-house monitoring of streams. These programs were intended to help MSD develop stormwater management strategies and improve the St. Louis County Storm Water Management Plan. The consent decree added the requirement of sampling to determine the effectiveness of sanitary and combined sewer overflow projects. MSD needed better high quality data collection services with the value-added benefit of a data management system capable of addressing key project objectives and management decisions.
Geosyntec's Scope of Services
Geosyntec worked with MSD to design a comprehensive water quality monitoring program, including quality assurance/quality control procedures, to enhance the value of historical and new water quality data. As part of our data management services, Geosyntec created a water quality database designed to maximize the quality and value of new, plus historical water quality data. Our database conforms to practices developed by the Methods and Data Comparability Board of the National Water Quality Monitoring Council, which promotes informed decision making. Historical water quality data were reviewed and compiled into the database.
Geosyntec trained MSD personnel to collect data at MSD's small urban stream sites. Geosyntec collects data at three Missouri River and six Mississippi River sites that lie within the third largest inland shipping port in the United States.. Geosyntec uses equal width increment and depth-integrated sampling procedures. The Missouri and Mississippi Rivers are sampled every two weeks using Geosyntec's 24-foot Sea Ark boat equipped with a boom and winch to safely sample under rigorous field conditions. Both dry and wet weather sampling is performed to help characterize the influence of St. Louis discharges and stormwater on receiving water quality. River/stream discharge measurements are recorded from nearby USGS gauging stations or measured directly using an Acoustic Doppler Current Profiler. We use “Clean Sampling” techniques for trace elements, according to USEPA Method 1669 procedures, to maintain the highest level of data quality.
Geosyntec has enabled MSD to receive the same water quality monitoring services historically provided by others in a timely manner and at a cost savings with the value added benefit of data management and analysis. Geosyntec has logged more than 7,500 staff hours and 20,000 river miles with a perfect safety record.