Water Report - 2016

2016 Water Report

The State’s Department of Environmental Services assessment of Thorndike Pond can be found at the following link.  We work with this agency on their Volunteer Lake Assessment Program.

http://des.nh.gov/organization/divisions/water/wmb/vlap/annual_reports/2015/documents/thorndike-jaffrey.pdf

We sample the lake water three times a year, once each in the months of June, July, and August.  The state participates in one of those samplings and takes additional information using equipment they have.  We sample at 5 locations: the two major inlets, the outlet at the dam, and at two different depths at the deep spot near Maxwell/Hamlin.  The beaches at the two camps and the town beach are also checked for E-coli.

The measurements at the beaches was rated “slightly bad” at the town beach and “very good” at both camps.  It is not uncommon for beaches that get heavy use to show elevated E-coli readings, which can sometimes lead to their closings.  I think the camp readings are more representative of the lake and what most of you can expect on your waterfronts.

Of the seven measurements made on the water samples three were rated as slightly bad, the others were all good.

  • pH is the most problematic measurement because not only are we rated slightly bad, but the trend in recent years has been to get worse.  This acidity is common in NH lakes, caused by a combination of acid rain and poor ANC attributed of our granite base.  The state average is 6.6 and the threshold for slightly bad is 6.5, we are at 6.4.  The lowest readings are at the inlets and the best reason is at the outlets, so I conclude it is not a problem of our making we just have to play the water we are given.
  • Phosphorus: the state average is 12 ug/L and we measured 15 at both inlets, 8 at both deep spots and 6 at the outlet.  High levels are common in stagnant water like that feeding into the lake.  The fact that it is better than the state average in the middle and gets even better as it leaves indicates to me that we don’t have properties on the pond that are hurting the pond with failed septic systems of fertilizing.
  • Chlorophyll: the state average is 4.58 mg/m3, and we are at 3.49 so better than the state average, even though worse than we want to be.