Baltimore City Stream Water Quality Indicators (poster)


The Baltimore City Water Quality Management Section presented two posters that describe the water quality and biological health of the three major stream systems in the City of Baltimore; Gwynns Falls, Jones Falls and Herring Run. One of the maps shows the network of water quality sampling stations established under the City of Baltimore's Municipal Stormwater Permit Program. The water quality at the stations is depicted using indicators (high, elevated and low) for metals, nutrients, pathogens and dissolved oxygen. The indicators are based on a methodology developed by the Maryland Department of Natural Resources for their statewide water quality inventory (305b report).

The other map shows the network of benthic macro-invertebrate sampling stations and a biological score indicating the health of the benthic community. The biological score is expressed as a percentage of the average scores of three minimally impacted streams (reference stations) in Baltimore County. The scores are based on the averages of all samples collected at each site, and were computed by a multi-metric scoring method.