Recommendations for Refinement of a Spatially Representative Non-tidal Water Quality Monitoring Network for the Chesapeake Bay Watershed

Prior to 2005, existing non-tidal water quality monitoring programs within the Chesapeake Bay watershed did not meet the Chesapeake Bay?s restoration priorities since a majority of these programs were only designed to address specific goals by various agencies. The CBP?s Non-tidal Water Quality Monitoring Workgroup began designing a monitoring network for the non-tidal Chesapeake Bay watershed to measure nutrient and sediment concentrations and loads, and for assessing progress toward meeting the water quality criteria of the Bay and its tributaries. Initial designs of a sampling network were completed, and 188 new and existing candidate stations were identified for inclusion in the network. It was believed that if all of the candidate stations were implemented, the CBP could address the objective of measuring the status and trends of nutrient and sediment concentrations and loads in the tributary strategy basins. However, it was not clear how well these stations address model calibration and verification issues or whether they would be capable of detecting and evaluating the effectiveness of BMPs designed to reduce sediment and nutrient loads to the Bay. To meet the intended objectives of the network, the Workgroup requested STAC to assess the spatial representativeness of current and proposed sites. Information gained from the review was used to enhance network design and prioritize the selection of future monitoring sites in light of limited funding for the monitoring network.