Water Resources Research Act Program

Details for Project ID 2004ME31B

Nutrient cycling within the Meduxnekeag River and the use of periphytic algae as an indicator of nutrient loading

Institute: Maine
Year Established: 2004 Start Date: 2004-04-01 End Date: 2006-03-31
Total Federal Funds: $15,300 Total Non-Federal Funds: $129,110

Principal Investigators: David Dail, Steve Kahl, Katherine Webster

Project Summary: A 20-mile segment of the Meduxnekeag River in Aroostook County, Maine, that traverses Houlton Band of Maliseet Indian (HBMI) tribal lands is experiencing substantial filamentous algal blooms in summer months. The algal blooms have lowered dissolved oxygen (DO) levels in the river to the extent that a 6-mile stretch within the segment has been deemed impaired by the Department of Environment Protection (DEP). Water chemistry data collected by the HBMI are available from 1995 to the present for this stretch of the river and indicate that the blooms may be phosphorus (P) limited, but that the algae are moderating stream chemistry and responding to flow dynamics to an extent that controls over algal production are unclear. A Watershed Protection Plan/Environmental Assessment for the Main Branch of the Meduxnekeag River was published in 1993, a Total Maximum Daily Load (TMDL) Report was published by the Department of Environmental Protection (DEP) in 2000, and the U.S. Geological Survey (USGS) is finalizing a sediment study it conducted this summer (2003). Currently, no research has linked the existing water quality data to nutrient dynamics in the river, or pinpointed the relative input contributions from point and non-point sources, of which there are many. These including unbuffered agricultural stream inputs, wetland, and lake recharge as well as industrial and wastewater effluent and proximity to impermeable surface inputs; all of these inputs are upstream of the Maliseet tribal lands. We propose to evaluate the underlying cause of the eutrophication by compiling and analyzing the existing data, investigating nutrient cycling in the river (including sediment and the water column), identifying nutrient loading areas and relative contributions of point and non-point sources, and determining temporal and spatial changes in the algae. Our overarching goal is to identify the causes of the problem, or to prioritize the likely causes, and thus provide supportive data that may lead to recommendations for remedy.