SESSION B:

Title: Stream TMDL Assessment as a Conservation Tool

Author: Melissa Evers
Stream Assessments, Maine Department of Environmental Protection, State House Station 17, Augusta, ME 04333, melissa.evers@maine.gov

Abstract:

Small streams are a vital component of virtually all of Maine’s freshwater ecosystems and they present unique assessment challenges due to their ephemeral nature. No ecosystem in Maine is without impact and Maine DEP is developing tools for gauging impacts to impaired streams that can be transferred to streams being considered for long term conservation efforts. Most small streams lack basic assessment documentation and this may mean native aquatic fauna are degraded or lost before the natural condition is known. Maine’s abundance of small streams and their location in the landscape meant they usually escaped point source discharges. Yet most altered landscapes directed runoff to these streams and polluted them with non-point sources runoff, which is responsible for impairing the longest mileage of flowing waters in Maine. The Clean Water Act requires Maine DEP to create a TMDL report that assesses and makes recommendations for all impaired waters on the 303 d list. A number of TMDL assessment methodologies are emerging to document and address the problems of impaired streams. The assessment tools combine routine and innovative approaches to establish benchmark environmental conditions that will be used for future comparisons. TMDL approaches for 9 small streams are presented along with monitoring results, watershed models and restoration recommendations. These approaches include; bacterial source tracking, load duration analysis, stressor identification, flow estimation techniques, continuous monitoring results, stormwater monitoring and landuse runoff models.