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2011 Secchi Dip-In Now In Full Swing Until July 17

From June 25 until July 17 volunteers participating in the Secchi Dip-In will be collecting transparency data in the United States and Canada. 
            Water transparency is affected by the color of the water and by particles of silt or clay or small plants called algae, and therefore is a simple measure of some forms of pollution.  Changes in water transparency may signal changes in land use or the success of efforts to restore waterbodies to better conditions.
            The Dip-In is an international effort in which volunteers produce a "snapshot" of the transparency of water in the United States and Canada.
            Sponsored by the North American Lake Management Society and the United States Environmental Protection Agency, the Dip-In is directed by Kent State University scientists, Dr. Robert Carlson and Dr. Jay Lee.
            Since the Dip-In began in 1994 in six Midwest states it has expanded to participation by more than 400 programs and 9,000 volunteers in the U.S., Canada, and several other countries.  The Dip-In has generated more than 41,000 water transparency records that are used to detect trends in transparency.
            Carlson said that he wanted to find a way to produce a scientific "snapshot" of the trends in water quality of the world's waterbodies. Such a project could only be done using the thousands of volunteers who routinely measure transparency in local volunteer programs. The Dip-In is a chance for volunteers to think and contribute globally by taking a measurement in their local environment.
            Although the Dip-IIn accepts data from all types of turbidity instruments, m ost volunteers will use an instrument called a "Secchi disk," a flat, horizontal, black and white disk that is lowered from a rope into the water until it disappears. The depth the disk disappears is a measure of the transparency of the water.  The disk itself is named after the Jesuit priest, Pietro Angelo Secchi, who first used the disk more than 150 years ago.
            Previous Dip-In's have provided valuable information about transparency. Transparencies found during the Dip-In range from one inch to more than 65 feet. Waterbodies in the northern parts of the United States and in Canada typically have the clearest lakes, while lakes in agricultural regions of the Midwest have some of the lowest transparencies.  Remarkably, most of the lakes that are exhibiting change are also in this northern part of the continent.
            The Dip-In has found that the volunteer's perception of water quality varies considerably from region to region. A person in Minnesota, Maine or Canada, for example, may think that a lake is degraded if the transparency is six feet while in other states, a lake with a transparency of only a foot may be considered beautiful. 
            Carlson suggests that these regional differences mean that people become accustomed to the quality that they see every day. Most sobering may be the possibility that everyone grows up thinking that their environment is normal. Small changes in water quality may go unnoticed. Fortunately, there are volunteer monitors who record these changes in water quality year after year. Without their observations, our environment might change unnoticed.
            For more information, visit The Secchi Dip-In website.  For more information on Lake Management in Pennsylvania check out the Pennsylvania Lake Management Society or contact Kerilynn Frey by calling 570-864-3847.


7/4/2011

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