July 12, 2016

 

LOCAL RIVERS GENERALLY GOOD THIS WEEK

 

The Souhegan Watershed Association volunteers found better than expected water quality in the local rivers this week. The Merrimack River between Manchester and Tyngsborough continues to have low, excellent E. coli levels. And this has been true all summer. Because of its size, the Merrimack River usually tests good; it’s only after big rainstorms that the E. coli levels increase beyond the acceptable range.

 

The Souhegan River is a much smaller river and so is more influenced by E. coli bacteria. Typically stretches where the river meanders slowly back and forth and through population centers the E. coli levels are raised to unacceptable levels. And that’s what the tests found this week. Downtown sections through Greenville, Wilton, and Milford had readings higher than acceptable. The downtown section in Wilton had the worst level seen this week – 461. This would be a dangerous level for swimming.

 

The stretch through downtown Milford was still above acceptable, but much lower than expected and much lower than two weeks ago – the test at the Swing Bridge was 166. But none of these places are known for bathing.

 

The E. coli levels at swimming spots is what’s important with all this hot weather. And the good news is that all the swimming spots tested good this week. Watson Park in Merrimack continues to have excellent results. Although SWA monitors every two weeks, this site is monitored every week and the results are posted at the park. The results here have been good for the last few weeks. The Horseshoe in Wilton had the highest number this week, but at 60 this is still considered excellent. Generally the E. coli numbers this week are considered quite good, better than expected.

 

Numbers less than 88 are excellent. Numbers higher than 126 are not acceptable for swimming.

 

Both rivers continued to have very low flows due to the lack of rain. The Souhegan has been running below its historical average all summer – the last time there was normal flow was back in March. Flow today should be almost twice as much just to get back to normal. These low flows mean that any pollution getting into the rivers has little to dilute it. The Merrimack is a much larger river and flow is largely controlled by upstream and downstream dams so the effects of pollution are not as great.

 

The dissolved oxygen levels are still running at an acceptable level. The dissolved oxygen levels determine the health of the river for the fish and other river animals. Both rivers have historically done very well and continue at very acceptable levels. The actual readings and explanations for DO and other tests is listed at www.souheganriver.org. Past years’ readings are also listed there.

 

The rivers will be tested again every two weeks during the summer. Thirty volunteers, many of whom have been with the program for many years, adopt a site and test every other Tuesday morning and carry the samples to 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 July 26.

 

Here are the results for the test on July 12:

 

E-COLI MONITORING RESULTS FOR TESTS TAKEN ON JULY 12, 2016

 

SOUHEGAN RIVER SITES:

 

  1. Billy Ward Pond, Ashburnham  #1 44.1; #2  1.0

  2. SoR  333  River Road above Water Loom Pond, New Ipswich  7.4

  3. SoR  320  Highbridge, New Ipswich  40.0

  4. SoR  309  Above Greenville Mill Pond, Greenville  128.1

  5. SoR  296  Downtown Greenville upstream of WWTP  105.0

  6. SoR  291  Green Bridge off Rte 31 below Greenville WWTP  235.9

  7. SoR  218  Below the Horseshoe, Wilton   60.2

  8. SoR  210  Downtown Wilton  461.1

  9. SoR  201  Pine Valley Mill, West Milford   NA

  10. SoR  170  Behind Hayward Field, West Milford   307.6

  11. SoR  155  Souhegan Valley Boys and Girls Club, Milford  290.9

  12. SoR  146  Swing Bridge, Milford  165.8

  13. SoR  133  Riverside Cemetery, Milford   62.4

  14. SoR  130  Behind Lorden Plaza, Milford  81.6

  15. SoR  122  Amherst Country Club  115.3

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

  17. SoR  095  Boston Post Road Canoeport, Amherst  85.5

  18. SoR  057  Indian Ledges, Merrimack  28.1

  19. SoR  034  Turkey Hill Bridge, Merrimack  NA   

  20. SoR  001  Watson Park, Merrimack  26.2

 

 

MERRIMACK RIVER SITES:

 

1.      Mer  600  Above Amoskeag Dam, Manchester  NA

2.      Mer  590  Arms Park, Manchester  NA

3.      Mer  580  Upstream of Piscataquag River, Manchester   NA

4.      Mer  570  Goffs Falls, Litchfield  84.2

5.      Mer  560  Depot Street, Merrimack    50.4

6.      Mer  550  Upstream of Souhegan River, Merrimack   34.5

7.      Mer  540  Thorntons Ferry, Merrimack  53.8

8.      Mer  530  Greeley Park, Nashua  17.3

9.      Mer  520  Taylors Falls Bridge, Nashua    25.9

10.  Mer  510  Sagamore Bridge, Hudson  63.7

11.  Mer  500  Pheasant Lane Mall, Hudson    NA

12.  Mer  490  Upstream of Tyngsboro Bridge  23.3

                                       

                                               

Flow on Upper Souhegan  was 14 CFS and expected flow for that date is 37

Flow on Lower Souhegan  was 45 CFS and historic flow for that date is 71

Flow on Merrimack was 1520 CFS and historic flow for that date is 1980

RAINFALL – rain Saturday, showers Sunday, then clear and warm

 

 

DO MONITORING RESULTS FOR TESTS TAKEN ON JULY 12, 2016

 

SOUHEGAN RIVER SITES:

 

  1. Billy Ward Pond, Ashburnham #1  7.14; #2  7.53

  2. SoR  333  River Road above Water Loom Pond, New Ipswich  7.12

  3. SoR  320  Highbridge, New Ipswich  8.57

  4. SoR  309  Above Greenville Mill Pond, Greenville  7.74

  5. SoR  296  Downtown Greenville upstream of WWTP  8.57

  6. SoR  291  Green Bridge off Rte 31 below Greenville WWTP  8.53

  7. SoR  218  Below the Horseshoe, Wilton  9.58

  8. SoR  210  Downtown Wilton  9.34

  9. SoR  201  Pine Valley Mill, West Milford   NA

  10. SoR  170  Behind Hayward Field, West Milford    7.82

  11. SoR  155  Souhegan Valley Boys and Girls Club, Milford  7.90

  12. SoR  146  Swing Bridge, Milford  8.57

  13. SoR  133  Riverside Cemetery, Milford   8.15

  14. SoR  130  Behind Lorden Plaza, Milford  8.06

  15. SoR  122  Amherst Country Club  7.50

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

  17. SoR  095  Boston Post Road Canoeport, Amherst  6.74

  18. SoR  057  Indian Ledges, Merrimack  8.51

  19. SoR  034  Turkey Hill Bridge, Merrimack    NA

  20. SoR  001  Watson Park, Merrimack  8.99

 

 

MERRIMACK RIVER SITES:

 

13.  Mer  600  Above Amoskeag Dam, Manchester  NA

14.  Mer  590  Arms Park, Manchester  NA

15.  Mer  580  Upstream of Piscataquag River, Manchester   NA

16.  Mer  570  Goffs Falls, Litchfield  7.67

17.  Mer  560  Depot Street, Merrimack    7.76

18.  Mer  550  Upstream of Souhegan River, Merrimack   7.87

19.  Mer  540  Thorntons Ferry, Merrimack  7.99

20.  Mer  530  Greeley Park, Nashua  8.32

21.  Mer  520  Taylors Falls Bridge, Nashua  7.32 

22.  Mer  510  Sagamore Bridge, Hudson  7.33

23.  Mer  500  Pheasant Lane Mall, Hudson   

24.  Mer  490  Upstream of Tyngsboro Bridge  8.16

 

 

 

pH MONITORING RESULTS FOR TESTS TAKEN ON JULY 12, 2016

 

SOUHEGAN RIVER SITES:

 

  1. Billy Ward Pond, Ashburnham

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

  3. SoR  320  Highbridge, New Ipswich 

  4. SoR  309  Above Greenville Mill Pond, Greenville 

  5. SoR  296  Downtown Greenville upstream of WWTP 

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

  7. SoR  218  Below the Horseshoe, Wilton  

  8. SoR  210  Downtown Wilton   6.93

  9. SoR  201  Pine Valley Mill, West Milford    

  10. SoR  170  Behind Hayward Field, West Milford   

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

  12. SoR  146  Swing Bridge, Milford 

  13. SoR  133  Riverside Cemetery, Milford    6.62

  14. SoR  130  Behind Lorden Plaza, Milford 

  15. SoR  122  Amherst Country Club 

  16. SoR  116  Amherst Conservation land Fairway Road, Amherst   

  17. SoR  095  Boston Post Road Canoeport, Amherst  6.74

  18. SoR  057  Indian Ledges, Merrimack 

  19. SoR  034  Turkey Hill Bridge, Merrimack    

  20. SoR  001  Watson Park, Merrimack