NEWS NOTES ON SUSTAINABLE WATER RESOURCES NWQMC Webinar on Applying the Biological Condition Gradient to Support Water Quality Management NWQMC Webinar Series Using the Biological Condition Gradient to Develop ProtectiveBiological Thresholds for Diverse Stream Types in Minnesota Presented byWill Bouchard, Ph.D., Research Scientist, Minnesota Pollution Control AgencyThursday, September 5th, 2:00 – 3:00 p.m. EDT The state of Minnesota updated its statewide biological assessment tools (i.e., Indices of Biotic Integrity and Biological Criteria) in 2017 for streams and rivers. Minnesota includes a range of stream types from northern forest, cold water streams to prairie rivers. This natural diversity coupled with different stressor gradients between stream types posed challenges for developing protective and consistent biological thresholds that comply with state and federal regulations for determining attainment of beneficial uses. An important tool for establishing consistency across the state was the Biological Condition Gradient (BCG). BCG models were developed for each stream type and used to interpret changes in biological condition regardless of region or stream type. This analysis was especially important for preventing biological criteria from being under protective in regions where widespread disturbance is present (e.g., prairie region). The BCG models were also integral to the development of tiered goals as part of tiered aquatic life uses (TALU) framework The webinar is free ; pre-registration is required . Please login 10 minutes early.