E-coli

 

Since storm-water carries pollutants from the watershed to streams and ponds, the Six Ponds Association decided last summer to do some storm sampling.

 

During the height of three heavy rainstorms, samples were collected from the outfall pipe which drains Plymouth Estates roads and from the stream running from Little Long Pond to Long Pond.

 

E-coli test results in 2002   (the acceptable limit is 235 colonies/100mls)

Outfall pipe test results         colonies/100mls                   

                        6/15/02                       6,400                         

                        7/29/02                     36,000

                        9/16/02                   110,000

Stream test results                colonies/100mls

                        7/29/02                       3,600

 

 

What’s being done - When the initial June results were obtained, Six Ponds members visited the Town’s Public Health Director who asked for two more validation tests. The results above show that an even greater E-coli level was found in July and a very serious level was found in September. The acceptable recreation level is just a fraction of what was obtained (235 colonies/100mls). Six Ponds Executive Committee members then visited with the Health Director who could take no action because there is no Town owned public interest at Long Pond. He said, however, that these levels would have closed the PEA beach immediately if it was a public beach. Six Ponds then appeared at a full Board of Public Health meeting and spoke with the Public Works Director who agreed to clean some of the catchment basins. He also agreed to open catchment grates during a heavy Spring rainstorm to allow us to sample selected basins to isolate the source(s).  These high E-coli levels could come from overflowing septic systems or from something as simple as the dumping of cat litter into a catchment drain.  We will follow up this Spring.

 

Caution: Plymouth Estates residents are cautioned not to swim at the PEA beach for a few days after heavy rainstorms.

 

Problem Locations

1.  
Outfall Pipe: the samples were taken right at the mouth of the stormwater outfall pipe which drains part of the Plymouth Estates subdivision. The pipes feeding to this outfall pipe collect from 2000 feet of roadway with about 50 homes. There are storm grates every 100 to 200 feet along parts of the following roads: Long Pond Road, Oar & Line Road, Thatcher Road and Clark Road.

2.  Stream: The 9,600 sample from the stream running from Little Long Pond was taken 30 feet upstream to avoid any influence from the outfall pipe. Note: Just this past month a high school science project found high E-coli levels in the stream. 

3. Adjacent areas - Great quantities of stormwater enter the stream directly from West Long Pond Road scuppers and from the two parking lots at the boat ramp.