Professor of Geoscience John Halfman, in association with the Finger Lakes Institute, the Environmental Studies program, and the Department of Geosciences, has received a $15,000 grant from the Owasco Lake Watershed Association that will purchase equipment and supplies needed to quantify nutrient loading from Dutch Hollow Creek into Owasco Lake.
Research that Halfman conducted in 2006 and 2007 identified a number of nutrient sources, including the Groton Wastewater Treatment Facility and runoff from agricultural areas. The data produced from the research put pressure on various groups to remedy the Groton situation, establishing a watershed inspector and other venues to improve the lake’s water quality.
A later survey revealed that water quality in Owasco Lake had improved in 2007 and 2008, only to then degrade in 2009 and 2010. The year-to-year difference is suspected to reflect the amount of runoff of nutrients from the watershed, as nutrient loading stimulates algal blooms, degrades water clarity, and stimulates a transition to blue-green algae, declining oxygen concentrations in the bottom waters, and the production of white foam. The threat to humans is now more real as some blue-green algae synthesize toxins.
Using an automated water sampler and stream data logger that will be purchased through the grant, Halfman will quantify nutrient loading of both phosphates and nitrates by determining the relative proportion of nutrients derived by runoff from precipitation compared to base-flow conditions. This summer, Maggie Stewart ’12, Lucia Melara ’14, Emily Cummings ’13 and Abby Kent ’12 will be assisting Halfman in his research.
The grant will purchase a Teledyne ISCO 6712 Portable Water Sampler, which is programmed to automatically and autonomously sample runoff events. The grant will purchase of an In-Situ Aqua Troll 200 data logger, which will monitor and record stream’s height along with water temperature and salinity every hour over the entire field season. The data collected from these two devices is needed to differentiate and quantify nutrient loading during peak and base flow conditions, and will thus accurately determine nutrient loading to the lake.
At the end of the survey, which will take place over the course of the 2011 field season, Halfman will present his findings and submit a report with the data and analysis. He has been conducting similar surveys bi-monthly since 2006 and a summary of his data can be found online: http://people.hws.edu/halfman/Owasco/Index.htm.