Merrimack watershed bacteria results: July 9, 2019

Dear River and Watershed Friends,

Upper Merrimack Monitoring Program volunteers continue 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.

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 Pemigewasset107
2 Winnipesaukee31
3 Merrimack above FWWT Plant<10
4 Merrimack below FWWT Plant10
5 Merrimack Jamie Welch Park<10
6 Merrimack Route 4 Bypass31
7 Contoocook at Rivco20
8 Merrimack Sewalls Falls108
9 Merrimack Manchester St10
10 Merrimack Blue Seal20
11 Merrimack Garvins Falls<10

All sample results are as of Tuesday morning, July 9, 2019. Results may change from day-to-day, depending on upstream conditions and rainstorms.

You’ll hear from us again after the July 23 sampling day. 

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Michele L Tremblay                          Stephen C Landry
Program Manager                             Sampling Supervisor