Three Rivers Region Water Quality Monitoring with Allegheny County Sanitary Authority
USGS, in cooperation with the Allegheny County Sanitary Authority (ALCOSAN), is monitoring water quality changes related to wastewater infrastructure improvements in the Three Rivers region in Pittsburgh, Pennsylvania.
Many North American urban centers have “combined sewers” that route both municipal and industrial waste and stormwaters to local and regional treatment plants. High inflows during heavy storm events have the potential to overload combined sewers, and they therefore often have discharge points (“combined sewer overflows” outfalls, or CSOs) that route excess waters into nearby streams and rivers to prevent sewer backups/failures that may pose a public health and safety risk.
In Allegheny County, Pennsylvania, there are 320 CSO outfalls that can discharge runoff, sewage, and industrial wastewater into rivers and streams during storm events. These discharges may degrade water quality by contributing bacteria and pathogens, excess nutrients, metals, and other pollutants to receiving waters. Some of these pollutants can create low oxygen concentrations that also impact stream health. ALCOSAN has begun a large project in the Three Rivers Region to expand their regional treatment plant and to upgrade and repair combined sewer infrastructure throughout Allegheny County’s to significantly reduce CSOs.
USGS, in cooperation with ALCOSAN, has started a muti-year sampling campaign to characterize water-quality conditions before and after infrastructure repairs and upgrades, targeting both wet and dry weather events. Samples are being collected in the Ohio River, Allegheny, and Monongahela River Basins, at a total of 27 river and tributary locations. Data collected in this effort will help characterize baseline water-quality conditions, demonstrate effects of CSO discharges on receiving waters, and help assess water-quality changes resulting from ALCOSAN’s infrastructure repairs and improvements.
USGS, in cooperation with the Allegheny County Sanitary Authority (ALCOSAN), is monitoring water quality changes related to wastewater infrastructure improvements in the Three Rivers region in Pittsburgh, Pennsylvania.
Many North American urban centers have “combined sewers” that route both municipal and industrial waste and stormwaters to local and regional treatment plants. High inflows during heavy storm events have the potential to overload combined sewers, and they therefore often have discharge points (“combined sewer overflows” outfalls, or CSOs) that route excess waters into nearby streams and rivers to prevent sewer backups/failures that may pose a public health and safety risk.
In Allegheny County, Pennsylvania, there are 320 CSO outfalls that can discharge runoff, sewage, and industrial wastewater into rivers and streams during storm events. These discharges may degrade water quality by contributing bacteria and pathogens, excess nutrients, metals, and other pollutants to receiving waters. Some of these pollutants can create low oxygen concentrations that also impact stream health. ALCOSAN has begun a large project in the Three Rivers Region to expand their regional treatment plant and to upgrade and repair combined sewer infrastructure throughout Allegheny County’s to significantly reduce CSOs.
USGS, in cooperation with ALCOSAN, has started a muti-year sampling campaign to characterize water-quality conditions before and after infrastructure repairs and upgrades, targeting both wet and dry weather events. Samples are being collected in the Ohio River, Allegheny, and Monongahela River Basins, at a total of 27 river and tributary locations. Data collected in this effort will help characterize baseline water-quality conditions, demonstrate effects of CSO discharges on receiving waters, and help assess water-quality changes resulting from ALCOSAN’s infrastructure repairs and improvements.