Merrimack watershed bacteria results: June 25, 2019

Dear River and Watershed Friends,

Upper Merrimack Monitoring Program volunteers began the bacteria sampling season with 100% sampling at 100% of the eleven sites on the Merrimack River from Franklin to Bow and on the Pemigewasset, Winnipesaukee, and Contoocook Rivers. This week begins an excellent trend.

All other samples are below the Class A standard and well within the Class B standard.

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 description
1 Pemigewasset86
2 Winnipesaukee20
3 Merrimack above FWWT Plant10
4 Merrimack below FWWT Plant31
5 Merrimack Jamie Welch Park75
6 Merrimack Route 4 Bypass74
7 Contoocook at Rivco30
8 Merrimack Sewalls Falls52
9 Merrimack Manchester St41
10 Merrimack Blue Seal52
11 Merrimack Garvins Falls31

You’ll hear from us again after the July 9 sampling day. 

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Michele L Tremblay                          Stephen C Landry
Program Manager                             Sampling Supervisor