AMHERST, Mass. - Using satellite images from space along with volunteers who collect measurements and samples from lakes and ponds, University of Massachusetts researchers are developing a cost-effective way to monitor water quality and weed growth in the state’s waters. UMass is sharing its findings with the state Department of Environmental Management (DEM), and the U.S. Geological Survey (USGS).
The Cooperative Satellite Project, in its second year, compares data from the earth-orbiting Landsat 5 satellite with the volunteers’ measurements of water temperature, transparency, algal pigment (chlorophyll), and color plus basic weather data on the day the satellite passes over. The volunteers are part of the Massachusetts Water Watch Partnership, a statewide network of 75 lake and 15 river groups coordinated by the Water Resources Research Center at UMass. Paul J. Godfrey, director of the center, said the volunteers first participate in special training workshops and then make field measurements and collect samples for 75 lakes every 16 days to match the satellite schedule. Once during the summer they also map the weeds in each lake.
The measurements and samples collected by the volunteers help scientists interpret the Landsat images and provide researchers basic information about the state’s waters. By pooling their efforts, UMass, the DEM, and the USGS use their scarce resources in a way that provides each with information they need. "At present, we have recent data on very few of our 2,925 lakes," Godfrey said. "This project will make it possible to collect, inexpensively, basic water quality data on nearly all lakes and to determine how they have changed over the past 20 years using archived satellite images. But the success of the project hinges on having adequate field sampling."
A key breakthrough for the project came when Godfrey and his staff, working in his garage, developed a simple, inexpensive way for the volunteers to get high quality chlorophyll samples. Previously, samples had to be analyzed immediately or deep-frozen, an impossibility for volunteers. Now, the volunteers filter the water sample in the field or on their kitchen table and air dry the filter with a simple apparatus made of PVC pipe and a small fan. Then the filter is wrapped in foil and mailed to UMass for detailed analysis, Godfrey said.
Volunteer participation has nearly doubled this year, Godfrey said. Participants, many of whom live on or near the ponds and akes, said they were enthusiastic about the project because it provided them with training, equipment, and information they could use and has the lure of space technology being applied to a real down-to-earth need.