JULY 26

 

THUNDERSTORMS INCREASE E. COLI

 

E. coli levels on the local Souhegan and Merrimack Rivers increased due to the thunderstorm that came through the area on Sunday afternoon. Low flow rivers don’t have the volume to dilute pollution being washed into storm drains and off river banks after large rainstorms that are preceded by drought conditions. And that’s what the SWA volunteers found when they checked the rivers on Tuesday morning.

 

The Merrimack River in Manchester had very high E. coli levels, probably the result of a direct sewage discharge into the river in Manchester. Any time the city’s combined sewage storm drains exceed the capacity of the sewage treatment plant to treat the flows, a number of valves direct flows right into the river. A count below 88 is considered clean enough for swimming in the river. The count at Goffs Falls near the railroad bridge crossing the river exceeded 2400. However, the large volume of water in the Merrimack was able to dilute the pollution to less than the 88 number by the time the river reached the canoe access at Reeds Ferry in Merrimack. And the river continued to improve all the way to Tyngsborough.

 

Volunteers monitor the entire length of the Souhegan River and found that this smaller river did not fare as well. The highest level found was as the river came through the centers of towns in Wilton and Milford. Downtown Wilton registered 687; the Oval in Milford was 140.

 

Swimming holes on the Souhegan did much better. Watson Park in Merrimack has been at a dangerous level for the last week; this week the level improved to 99.  Numbers less than 88 are excellent. Numbers higher than 126 are not acceptable for swimming.

At the 99 level some people, especially young children or those with less resistant immune systems, could experience gastrointestinal problems and ear and eye infections, swimmer’s ear. Swimmers that can’t keep out of the water during these hot days should try not to get their heads wet. Watson Park is the only site monitored every week; all other sites are monitored biweekly.

 

The Horseshoe in Wilton tested at 48, excellent. All other spots where swimmers might congregate also tested clean enough.

 

SWA monitors also for dissolved oxygen in both rivers. This gives the best general indication of the health of the river itself. And monitors found generally good levels of DO again this week. This has been true all season. The rivers are clean for fish and other river creatures and for the environment. More information about DO and the actual readings for each site are listed at www.souheganriver.org.

 

Watson Park will be tested again next Tuesday and the results posted at the park; all other sites will be tested again the following Tuesday.

 

Thirty volunteers, many of whom have been with the program for many years, spend about 20 minutes at the river taking samples and then bring the samples to one of the local wastewater treatment plants in Greenville, Milford, Merrimack, Manchester and Nashua where the samples are processed by licensed professionals. There are still sites available and new volunteers are always welcome; sites with NA are open right now. More information is available on the SWA website.

 

The next test will be on August 9.

 

Here are the results for the test on July 26:

 

 E-COLI MONITORING RESULTS FOR TESTS TAKEN ON JULY 26, 2016

 

SOUHEGAN RIVER SITES:

 

  1. Billy Ward Pond, Ashburnham  #1  4.1;  #2  3.1

  2. SoR  333  River Road above Water Loom Pond, New Ipswich  13.2

  3. SoR  320  Highbridge, New Ipswich  68.9

  4. SoR  309  Above Greenville Mill Pond, Greenville  32.3

  5. SoR  296  Downtown Greenville upstream of WWTP  NA

  6. SoR  291  Green Bridge off Rte 31 below Greenville WWTP  NA

  7. SoR  218  Below the Horseshoe, Wilton   47.9

  8. SoR  210  Downtown Wilton  686.7

  9. SoR  201  Pine Valley Mill, West Milford   193.5

  10. SoR  170  Behind Hayward Field, West Milford    195.6

  11. SoR  155  Souhegan Valley Boys and Girls Club, Milford  95.8

  12. SoR  146  Swing Bridge, Milford  139.6

  13. SoR  133  Riverside Cemetery, Milford   127.4

  14. SoR  130  Behind Lorden Plaza, Milford  76.7

  15. SoR  122  Amherst Country Club  135.4

  16. SoR  116  Amherst Conservation land Fairway Road, Amherst    NA

  17. SoR  095  Boston Post Road Canoeport, Amherst  67.6

  18. SoR  057  Indian Ledges, Merrimack  18.7

  19. SoR  034  Turkey Hill Bridge, Merrimack   107.1

  20. SoR  001  Watson Park, Merrimack  98.8

 

 

MERRIMACK RIVER SITES:

 

1.      Mer  600  Above Amoskeag Dam, Manchester  16.0

2.      Mer  590  Arms Park, Manchester  344.8

3.      Mer  580  Upstream of Piscataquag River, Manchester    NA

4.      Mer  570  Goffs Falls, Litchfield  >2419.6

5.      Mer  560  Depot Street, Merrimack    64.5

6.      Mer  550  Upstream of Souhegan River, Merrimack   60.9

7.      Mer  540  Thorntons Ferry, Merrimack  57.3

8.      Mer  530  Greeley Park, Nashua  25.3

9.      Mer  520  Taylors Falls Bridge, Nashua   NA

10.  Mer  510  Sagamore Bridge, Hudson  7.5

11.  Mer  500  Pheasant Lane Mall, Hudson   NA

12.  Mer  490  Upstream of Tyngsboro Bridge  5.2

                                       

                                               

Flow on Upper Souhegan  was 6 CFS and expected flow for that date is 46  Temperature 23C

Flow on Lower Souhegan  was 23 CFS and historic flow for that date is 54

Flow on Merrimack was 1670 CFS and historic flow for that date is 1640  Temperature 25C

RAINFALL – Sunday brief thunderstorm, hot weather

 

 

 DO MONITORING RESULTS FOR TESTS TAKEN ON JULY 26, 2016

 

SOUHEGAN RIVER SITES:

 

  1. Billy Ward Pond, Ashburnham #1  7.11; #2  7.35

  2. SoR  333  River Road above Water Loom Pond, New Ipswich  7.31

  3. SoR  320  Highbridge, New Ipswich  7.64

  4. SoR  309  Above Greenville Mill Pond, Greenville  6.94

  5. SoR  296  Downtown Greenville upstream of WWTP  NA

  6. SoR  291  Green Bridge off Rte 31 below Greenville WWTP  NA

  7. SoR  218  Below the Horseshoe, Wilton   8.31

  8. SoR  210  Downtown Wilton  8.26

  9. SoR  201  Pine Valley Mill, West Milford   NA

  10. SoR  170  Behind Hayward Field, West Milford    6.62

  11. SoR  155  Souhegan Valley Boys and Girls Club, Milford  7.55

  12. SoR  146  Swing Bridge, Milford  7.35

  13. SoR  133  Riverside Cemetery, Milford    6.54

  14. SoR  130  Behind Lorden Plaza, Milford  6.41

  15. SoR  122  Amherst Country Club  5.94

  16. SoR  116  Amherst Conservation land Fairway Road, Amherst   NA

  17. SoR  095  Boston Post Road Canoeport, Amherst  5.99

  18. SoR  057  Indian Ledges, Merrimack  7.25

  19. SoR  034  Turkey Hill Bridge, Merrimack    7.03

  20. SoR  001  Watson Park, Merrimack  7.99     

 

 

MERRIMACK RIVER SITES:

 

13.  Mer  600  Above Amoskeag Dam, Manchester  7.58

14.  Mer  590  Arms Park, Manchester  7.75

15.  Mer  580  Upstream of Piscataquag River, Manchester    na

16.  Mer  570  Goffs Falls, Litchfield  6.82

17.  Mer  560  Depot Street, Merrimack    7.46

18.  Mer  550  Upstream of Souhegan River, Merrimack   NA

19.  Mer  540  Thorntons Ferry, Merrimack  7.44

20.  Mer  530  Greeley Park, Nashua  7.75

21.  Mer  520  Taylors Falls Bridge, Nashua    NA

22.  Mer  510  Sagamore Bridge, Hudson  8.03

23.  Mer  500  Pheasant Lane Mall, Hudson    NA

24.  Mer  490  Upstream of Tyngsboro Bridge  7.85