By Roger Segelken
Cornell researchers are reporting progress in attempts to identify problems and propose solutions for economically and environmentally sustainable agriculture in the New York City watershed.
Representatives of the farming community in the five-county Catskill-Delaware watershed, as well as officials from state and city agencies, were brought up to date in an April 19 campus visit for Research Exploration Day.
The round of briefings and laboratory tours was presented by the Center for the Environment and Cornell's New York State Water Resources Institute (WRI).
WRI is coordinating a universitywide research and outreach effort, funded mainly by the New York City Department of Environmental Protection, to reduce water pollution at the source and help New York City to avoid installation of a multibillion-dollar filtration system that otherwise will be required to meet federal clean-water standards. Pollution monitoring and clean-up efforts have focused both on farming operations and small municipalities in the watershed, and last Friday's presentation was the researchers' chance to tell what they're doing for the farms.
WRI's work with New York City on the project began in 1991, and it is now in the second phase, which will continue through 1997.
"This is a win-win-win project," said College of Veterinary Medicine Dean Franklin M. Loew, welcoming members of the Watershed Agricultural Council and the Watershed Agricultural Program Advisory Committee. "Water consumers in New York City are winning, agriculture in New York state is winning and so are the livestock we are examining for pathogens."
The dean was referring to the "Epidemiological Risk Assessment Study of Giardia and Cryptosporidium parvum in Dairy Cattle in the New York City Watershed," which is directed by Hussni O. Mohammed, associate professor of epidemiology in the College of Veterinary Medicine. The two pathogenic parasites from cattle (as well as from wild animals and humans) can enter water supplies and cause sometimes-fatal disease in water drinkers. Susan E. Wade, a parasitologist in the Veterinary Diagnostic laboratory, reported results of on-farm sampling of livestock for the microorganisms. Her laboratory also is testing wildlife on farmlands and on watershed property controlled by the city, she said.
To illustrate the potential for contamination by the microscopic organisms, briefing participants were invited to enter a contest and guess the number of Cryptosporidium oocysts (the egg-like form of the parasite that is shed in feces) in a vial of murky water.
"Think red," said William C. Ghiorse, professor and chairman of the Section of Microbiology and leader of the pathogen viability part of the watershed study. He held up a Cornell-red folder containing research reports, but the microbiologist was referring to the telltale color that dead C. parvum oocysts display in a fluorescence microscopy assay that his group developed. In the dye-permeability viability assay, viable oocysts show up as blue or colorless, and have potential to infect other animals, including humans. "Now we can tell the difference," Ghiorse said.
Michael F. Walter, professor and chairman of the Department of Agricultural and Biological Engineering, reported progress by the watershed-farm hydrology group in developing risk assessment models to predict rainwater runoff in the hilly Catskill area.
The best existing hydrology tools were developed for flatter land, such as that found in the Iowa corn belt, Walter noted. The Cornell models can tell farmers where to build water-diversion improvements and when not to spread manure on fields at particular times of year.
Reporting work by the integrated nutrient management group, Senior Extension Associate Stuart Klausner said small farms can have "a more disastrous impact on water quality" than larger farms if their animal density-per-acre is greater. "Nutrients" are nitrogen, phosphorous and potassium that are essential for plant and animal growth but which can pollute water when they escape from the farm. An integrated approach to nutrient management tries to reduce the input of the three elements to optimal levels -- by adjusting cattle feed mixes, for example -- to save money for producers and reduce pollution, Klausner said.
The nine million people who drink New York City's water need an element of assurance that the water is safe, said Richard I. Coombe, a Sullivan County beef farmer who is the chairman of the Watershed Agricultural Council. "And we (farmers) need to have a working watershed that protects water quality. That's not possible without standards and best-management practices to protect water quality," he said.
An alumnus of the College of Agriculture and Life Science, Coombe said the New York program "is being looked at all across the country and in Europe as a yardstick for watershed protection. We have the chance," he told fellow farmers and the Cornell scientists, "to write the book, to enable people to live and work in a watershed, for America and the world."