Bacteria days: results for August 24, 2017 (last of the season)

Dear River and Watershed Friends,

Upper Merrimack Monitoring Program volunteers closed out 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. Yesterday was the last sampling day of the season. We plan to begin again in late June 2018.

You may recall that we had high counts at Site 6 on July 13 and then at Site 1 on July 27? We checked the sites and found nothing unusual. For this last sample date, we have an identical, high reading at Site 1 again: 1,299.7 colonies per 100 milliliters of river sample water. One of our working theories for why we had bacteria spikes is that algal growth, which has been common this summer, has created a medium for bacteria to breed. There may have been transient animal (including human animals) activity in the area just before the samples were taken. We remain vigilant and will be watching conditions at these two sites.

As a reminder,  the readings shown below are the 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 Pemigewasset 1,299.7
2 Winnipesaukee 39.9
3 Merrimack above FWWT Plant 198.9
4 Merrimack below FWWT Plant 48.1
5 Merrimack Jamie Welch Park 61.3
6 Merrimack Route 4 Bypass 33.6
7 Contoocook at Rivco 44.8
8 Merrimack Sewalls Falls 52.8
9 Merrimack Manchester St 14.6
10 Merrimack Blue Seal 59.4
11 Merrimack Garvins Falls 14.4

You’ll hear from us again next year when sampling begins in June. In the meantime, there’s always work to be done. Bug Nights 2018 is slated to begin in January. If you want to be part of the winter fun, please visit the UMMP page or call 603.796.2615. We’d be happy to tell you all about it.

Thank you to our volunteer monitors, Adopt-a-River Site Sponsors, sample courier, and Franklin Waste Water Treatment Plant. We cannot begin to express how much we appreciate your leadership and dedication to this important program. As volunteers who manage an all-volunteer staffed program, our volunteers inspire us.

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Michele L Tremblay                          Stephen C. Landry
Program Manager                             Sampling Supervisor