Merrimack watershed bacteria results: August 11, 2020

Dear River and Watershed Friends,

Upper Merrimack Monitoring Program volunteers began the 2020 bacteria sampling season with 100% sampling at 100% of the four sites in Franklin.

This year, we are challenged by budget cuts and are not able to monitor at the remaining seven sites on the Merrimack River from below Franklin, down to Bow, and on the Contoocook River. We are working with the NH Department of Environmental Services and our Adopt-a-River Site sponsors to see how we may secure support to restore our full monitoring capacity for the remainder of this year or for 2021. 

The results shown below are the probable number of E. coli bacteria colonies for every 100 millilitres of water. Warm blooded animals (including humans) all have E. coli in their guts. State designated swim beaches are not allowed to exceed 88 colonies and Class B waters (all of our sites are Class B waters) should be below 406 colonies. Here are the details.

Site number and description8.11.20
#1 Pemigewasset River40
#2 Winnipesaukee River34
#3 Merrimack River above FWWTF10
#4 Merrimack River below FWWTF20

Sample results are as of Tuesday morning, August 11, 2020. Results may change from day-to-day, depending on upstream conditions and rainstorms.

For this sampling event, we are seeing excellent results. All sites meet the Class B designation for the Merrimack River and the more stringent designated swim beach standards. These low bacteria counts are expected when there has been little or no rain.

For these four sites, we feel that upper Merrimack watershed is relatively clean and healthy. You hear us say, “When it rains, it’s poor,” which means that you may wish to wait a day or so after it rains before recreating in a surface water. 

You’ll hear from us next year with new a round of sampling results. Please join us in thanking our Adopt-a-River Site Sponsors that make the Upper Merrimack Monitoring Program possible (listed in order of their sponsored sites).
Franklin Savings Bank
Franklin Waste Water Treatment Plant
Nelson Analytical
Essex Hydro
Aries Engineering
GZA Environmental
Granite Shore Power

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Michele L Tremblay                          Stephen C Landry
Program Manager                             Sampling Supervisor