Water Testing

Water Testing

Since its inception LLPA has participated in what is now known as the Citizens Lake Monitoring Network (CLMN), a Wisconsin DNR sponsored system of water quality testing and data management.  Once a month starting shortly after ice out volunteers visit six pre-established sites on the lake to perform testing.  Water clarity is checked by lowering a Secchi disk and recording the maximum depth at which it is visible.  (Current year-to-date results are shown here.)  Then a dissolved oxygen meter is used to record temperature and dissolved oxygen levels at one, three and five foot levels and at every five feet thereafter to the lake bottom.  The collected data is then uploaded to a DNR site known as SWIMS (Surface Water Integrated Monitoring System).  Learn more about  the Wisconsin DNR CLMN program.

At two of the sites water is collected from the upper six-foot water column.  Back on shore a measured amount intended for phosphorus testing is treated with acid (to destroy microorganisms which might alter phosphorus measurements) and another measured sample is drawn through a filter by use of a vacuum pump to collect chlorophyll.  The water sample and filter are then packed in ice and mailed to the State Laboratory of Hygiene in Madison where they are tested and the results are forwarded to DNR.

Even a single days testing gives a snapshot of water quality conditions, but more significantly over time the data indicate trends in lake health.   Both raw data and interpretative reports are available online.  Testing history for all participating Washburn County lakes, including the six Long Lake sites, can be found at http://dnr.wi.gov/lakes/clmn/Stations.aspx?location=66 .