AUGUST 26, 2014

 

 

E. COLI LEVELS FOLLOW PATTERN

 

Both the Merrimack River and the Souhegan River showed a predictable pattern when tested on Tuesday morning by the Souhegan Watershed Association’s long-standing volunteer monitoring program.

 

The good news is that the Merrimack River showed very acceptable E. coli levels all the way from Manchester to Tyngsborough. This has been the pattern for the last several years as the river has been cleaned up. Occasionally after heavy rainstorms that overwhelm the cities’ sewage treatment plants, the E. coli rises to an unhealthy level; but normally the Merrimack would test better than many public beaches.

 

The Souhegan River is a much smaller river and shows E. coli levels dramatically different – and much higher - than the Merrimack. The river begins in Ashburnham, Massachusetts, and crosses the border north into New Ipswich, Greenville, and Wilton. Here the E. coli level is in the 100 range.

 

The river passes into Milford and Amherst where it slows down and meanders back and forth through sandy soils. Here the E. coli level is in the 200 range.

 

When the river passes into Merrimack, the soil and gradient change and the E. coli level drops to an acceptable level.

 

This is exactly how the Souhegan River tested this week.

 

There are several swimming holes on the Souhegan – and these too tend to follow a pattern. The Horseshoe in Wilton, Indian Ledges, Turkey Hill Bridge and Watson Park in Merrimack usually test OK. They did this week. The Boston Post Road Canoeport in Amherst usually tests high – and it did again this week. The level here was 307.

 

Levels of E. coli higher than 88 are not acceptable for public swimming beaches in NH. Levels between 88 and 126 may be suitable for swimming but some people may experience gastrointestinal problems, rashes, or swimmers ear and eye. Levels higher than 400 are dangerous and should be avoided.

 

The program collects from 21 sites along the Souhegan and 11 on the Merrimack every two weeks during the summer months. Labs at the wastewater treatment plants in Manchester, Nashua, Milford, and Merrimack perform the tests.

 

Here are the individual results for E. coli at each site:

 

 

E-COLI MONITORING RESULTS FOR TESTS TAKEN ON AUGUST 26, 2014

 

SOUHEGAN RIVER SITES:

 

  1. Billy Ward Pond, Ashburnham  #1 93.4,  #2  8.4

  2. SoR  333  Water Loom Pond, New Ipswich  3.1

  3. SoR  320  Highbridge, New Ipswich  151.5

  4. SoR  309  Above Greenville Mill Pond, Greenville  119.8

  5. SoR  296  Downtown Greenville upstream of WWTP  57.6

  6. SoR  291  Green Bridge off Rte 31 below Greenville WWTP  95.9

  7. SoR  218  Below the Horseshoe, Wilton   66.3

  8. SoR  210  Downtown Wilton  108.1

  9. SoR  201  Pine Valley Mill, West Milford  224.7

  10. SoR  170  Behind Hayward Field, West Milford   150.0

  11. SoR  155  Souhegan Valley Boys and Girls Club, Milford  172.2

  12. SoR  146  Swing Bridge, Milford  290.9

  13. SoR  133  Riverside Cemetery, Milford  191.8  (DUP 224.7)  

  14. SoR  130  Behind Lorden Plaza, Milford  344.8

  15. SoR  122  Amherst Country Club  290.9

  16. SoR  116  Amherst Conservation land Fairway Road, Amherst   461.1

  17. SoR  095  Boston Post Road Canoeport, Amherst  307.6

  18. SoR  070   Seaverns Bridge, Merrimack  172.5

  19. SoR  057  Indian Ledges, Merrimack  46.5

  20. SoR  034  Turkey Hill Bridge, Merrimack  NA   

  21. SoR  001   Watson Park, DW Hwy, Merrimack  32.3

 

 

MERRIMACK RIVER SITES:

 

1.      Mer  600  Above Amoskeag Dam, Manchester  28.8

2.      Mer  590  Arms Park, Manchester  42.6

3.      Mer  570  Goffs Falls, Litchfield  39.9

4.      Mer  560  Depot Street, Merrimack   43.2

5.      Mer  550  Upstream of Souhegan River, Merrimack   37.9

6.      Mer  540  Thorntons Ferry, Merrimack  48.7

7.      Mer  530  Greeley Park, Nashua  41.7

8.      Mer  520  Taylors Falls Bridge, Nashua  79.4   

9.      Mer  510  Sagamore Bridge, Hudson  43.7

10.  Mer  500  Pheasant Lane Mall, Hudson  NA

11.  Mer  490  Upstream of Tyngsboro Bridge  34.1

 

                                   

Flow on Upper Souhegan was 64 CFS and expected flow for that date is 47  (bouncing around and dam at Water Loom lower)

Flow on Lower Souhegan was 75 CFS and historic flow for that date is 40

Flow on Merrimack was 3280 CFS and historic flow for that date is 1350

RAINFALL -  Clear, no rain.

Temperatures: Souhegan 19C;  Merrimack 20C





DISSOLVED OXYGEN RESULTS FOR TESTS TAKEN ON AUGUST 26, 2014

 

SOUHEGAN RIVER SITES:

 

  1. Billy Ward Pond, Ashburnham  #1 7.52  , #2  7.75

  2. SoR  333  River Road above Water Loom Pond, New Ipswich  7.55

  3. SoR  320  Highbridge, New Ipswich  8.57

  4. SoR  309  Above Greenville Mill Pond, Greenville  8.43

  5. SoR  296  Downtown Greenville upstream of WWTP  8.67

  6. SoR  291  Green Bridge off Rte 31 below Greenville WWTP   8.67

  7. SoR  218  Below the Horseshoe, Wilton   9.29

  8. SoR  210  Downtown Wilton  9.40

  9. SoR  201  Pine Valley Mill, West Milford   8.97

  10. SoR  170  Behind Hayward Field, West Milford   8.58

  11. SoR  155  Souhegan Valley Boys and Girls Club, Milford  8.20

  12. SoR  146  Swing Bridge, Milford  8.26

  13. SoR  133  Riverside Cemetery, Milford   8.44

  14. SoR  130  Behind Lorden Plaza, Milford  8.32

  15. SoR  122  Amherst Country Club  8.36

  16. SoR  116  Amherst Conservation land Fairway Road, Amherst  8.08

  17. SoR  095  Boston Post Road Canoeport, Amherst  7.78

  18. Sor   070   Seaverns Bridge, Merrimack  NA

  19. SoR  057  Indian Ledges, Merrimack  8.29

  20. SoR  034  Turkey Hill Bridge, Merrimack  NA  

  21. SoR  001   Watson Park, DW Hwy, Merrimack  8.97

 

 

 

MERRIMACK RIVER SITES:

 

12.  Mer  600  Above Amoskeag Dam, Manchester  8.50

13.  Mer  590  Arms Park, Manchester  8.85

14.  Mer  570  Goffs Falls, Litchfield  8.63

15.  Mer  560  Depot Street, Merrimack    8.45

16.  Mer  550  Upstream of Souhegan River, Merrimack   8.36

17.  Mer  540  Thorntons Ferry, Merrimack  8.13

18.  Mer  530  Greeley Park, Nashua  8.71

19.  Mer  520  Taylors Falls Bridge, Nashua    8.50

20.  Mer  510  Sagamore Bridge, Hudson  8.72

21.  Mer  500  Pheasant Lane Mall, Hudson    NA

22.  Mer  490  Upstream of Tyngsboro Bridge  8.66