Ongoing monitoring and evaluating lake water quality is critical to the long-term protection of our precious Lake Winona. Two samplings are performed each summer, once in June and again in August. Volunteers to collect samples are in need. Please contact Charlie Goodwin, Lake Water Testing Committee Chair to volunteer.
August 2018 Report Please read the following report. There have been some significant changes to the health of our lake, including a 14% increase in phosphorus levels in the bottom of the lake, worsening conductivity, and an increase in e-coli at one site. Testing for e-coli was impeded by our dry July and only 2 sites were tested. There was a slight improvement in the chlorophyll level. After the meeting a cyanobacteria bloom was found on Lake Winona. Additional testing is pending. Please review the information on limiting phosphate use near the lake.
2017 Results Lake Winona remains in good health. Phosphorus and chlorophyll-a are both listed as “Good” on the report. Unfortunately, pH and dissolved oxygen saturation are listed as “Slightly Bad” which means that data periodically exceed water quality standards or thresholds for a given parameter by a small margin. Oxygen, dissolved, is listed as “Bad” which means it may periodically exceed the standards or thresholds by a large margin. These are similar results to last year. Current recommendations to protect our lake are on the top of Page 2 of the attached report.
Winona continues to remain a mesotrophic body of water. Meaning is has a moderate amount of dissolved nutrients. Phosphorus is the biggest contributor to worsening transparency and conductivity numbers. We can help reverse this by NOT depositing leaves and lawn clippings into the lake; letting fallen leaves, trees or limbs remain in the lake; using household and personal cleaning products that contain phosphorus; and using phosphorus-based lawn fertilizers and weed killers near the water. New construction and upgrades are being made to several homes on West Shore – it’s critical these sites have silt fences in place to minimize runoff and keep construction debris out the lake.
Overall, water quality is fair, but phosphorus and chlorophyll-A continue to increase, while oxygen levels, transparency and conductivity continue to decline. The result is an increase in algae on the lake, which many of you have noticed this change first-hand over the last few years. While some of this is a natural occurrence as the lake ages, we can accelerate the problem by depositing leaves and lawn clippings into the lake; letting fallen leaves, trees or limbs remain in the lake; using household and personal cleaning products that contain phosphorus; and using phosphorus-based lawn fertilizers and weed killers near the water.
- Download the 2015 DES VLAP Test Summary
- Download Linda’s 2015 Water Quality Report Summary
- Download Excel file of water test results for 2011 through 2015
Overall, Lake Winona remains in good shape and has some very good readings in comparison to other lakes. We need to keep an eye on the usual things that elevate phosphorous, such as our septic systems, yard waste and storm run-off. Our biggest concerns at this time are the Hawkins Pond and North Inlets. Continued monitoring is necessary and we are pleased to have our new equipment purchased with the DES grant.
Results from our 2013 sampling results showed overall water quality remains high. First two testings of the season (June & Aug) found elevated levels of phosphorus and chlorophyl, however numbers are below levels of concern.
2011 – 2012 Results
Water quality remains high, with Lake Winona being in the top 10% of NH lakes with highest water quality. Download results from 2011 & 2012 water test results.
- Download the 2012 DES VLAP Test Summary (individual summary report not produced in 2011)
July 2010 Results
Lee Gardinier shared that results from the July 2010 water quality tests showed the lake’s water clarity (depth one can see the calibrated Secchi disk) was 6.0 meters (vu-scope result) This marks a return to higher clarity after lower readings last year.
August 2009 Summary Results
In March 2010, we received the DES summary report of water quality testing from a water sampling taken in August 2009. Art Dunscombe, Penny Burke and Lee Gardinier assisted the DES intern. Samplings were taken at the deepest spot of the lake, plus 4 key inlet points around the lake.
The results continue to be generally good. Transparency slipped lower again to 4.1 meters from recent readings near 6 meters. A few parameters of the test results indicated slightly elevated readings, namely chlorophyll, turbidity, and conductivity. Phosphorus and PH level tests were essentially unchanged. E-coli and chlorides were not tested in the 2009 sampling. A summary data sheet with more details will be provided at the June 26th meeting.
Going forward, DES strongly recommends we collect samples three times throughout the summer – once in June, July, and August.