Periphytic Algae as an Indicator of Nutrient Loading to the Meduxnekeag River

Lisa Fretwell

Project Status as of 2/28/04

A 20-mile segment of the Meduxnekeag River in Aroostook County, Maine that flows through Houlton Band of Maliseet Indian (HBMI) tribal lands is experiencing substantial filamentous algal blooms in summer months. The 289 square-mile Meduxnekeag River watershed is not only the most intensively farmed watershed in southern Aroostook County, but also flows through downtown Houlton and receives both point source and non-point source inputs before reaching tribal lands. Historical water quality monitoring of algae and nutrients has been limited in scope and inconclusive regarding factors contributing to the algal blooms. This project will investigate the nutrient sources and subsequent pathways within the Meduxnekeag River and determine if algal coverage can be used as an indicator of nutrient loading. This goal will be accomplished by monitoring nutrient concentrations in the water column in 2004 and 2005 between May and October. Additionally, the percent coverage of algal growth in the river will be mapped and algae will be analyzed for nutrient limitation and isotopic fingerprints of nutrient sources. An understanding of the relationship between nutrient sources and algal growth will be used to drive a restoration plan that will be a model for other areas of the state and beyond.