BRATTLEBORO -- Perhaps not surprisingly, this year's final round of regular E. coli tests from local waterways produced mixed results.
After a season of up-and-down bacterial levels, last week's samples again showcased the good (West River) and the bad (Williams River) while also featuring the reappearance of an off-the-charts reading (Whetstone Brook).
But Gloria Cristelli, acting president of Southeastern Vermont Watershed Alliance, found some positives in reviewing a summer's worth of testing after Tropical Storm Irene ravaged the area last summer.
"We did see some significant spikes (in E. coli)," Cristelli said. "But overall, I feel that the river waters themselves were not changed as much as we might have thought."
Alliance volunteers conducted seven samplings beginning in June, and the season started with widespread E. coli counts that exceeded the governmental standards for swimming suitability -- 235 bacteria per 100 milliliters of water.
That was cause for concern, since E. coli can cause gastrointestinal problems and other illnesses.
But bacterial levels dipped as the summer wore on, apparently due to much drier conditions. Alliance administrators say heavy precipitation can wash large amounts of E. coli, which is found in fecal matter from humans and other warm-blooded animals, into waterways.
The alliance's Sept. 5 test, though, showed the return of much higher readings. Laurie Callahan,
Overall, 10 of the 21 tested sites exceeded the federal "swimming suitability" standard.
And, once again, the Williams River was a trouble spot, with four of the five test areas showing E. coli counts above that standard. Those were in Chester below the wastewater-treatment plant (361 E. coli), at the Missing Link Road Bridge (462), at Rainbow Rock swimming hole (518) and above the confluence with the Middle Branch of the Williams River (1,300).
Also showing elevated E. coli levels after several cleaner tests were Saxtons River below the wastewater-treatment facility (readings of 1,414 and 1,554), Saxtons River at the Bellows Falls/Westminster sandy beach (261) and North Branch Brook in Jamaica at Pike's Falls (345).
And the Whetstone Brook returned as a problem area, with readings of 281 at Stark Road, 291 in West Brattleboro at Dettman Drive and greater than 2,420 E. coli at Brattleboro Food Co-op.
The latter reading means bacterial levels were too high to be measured by the alliance's testing method. The co-op spot was one of three that exceeded not only the E. coli swimming standard but also the 575-per-100-milliliters governmental standard for other recreational activities such as boating or fishing.
Cristelli said she intends to contact the Vermont Agency of Natural Resources regarding sites that consistently showed high E. coli counts.
"We want to try to find out, how do we get something done about these sites," Cristelli said.
On the other hand, some areas continued to show low E. coli levels in spite of recent rainfall. These included Rock River at Indian Love Call and all eight sites on the West River.
In fact, four West River sites -- Brattleboro at Milk House Meadows, Dummerston Covered Bridge, Brookline bridge and Ellen Ware Road swim hole -- were considered suitable for swimming all summer long.
Callahan said the alliance will conduct one last abbreviated test -- just four sites that had been monitored on a once-a-month schedule -- on Oct. 3. She said "compilation and analysis of the collected data" will happen in September and October.
Samples also have been analyzed for other factors including pH, conductivity, phosphorous and nitrate levels. Additionally, air and river-water temperatures have been recorded.
Callahan said a "full discussion" of those results will be available in a report by late fall or early winter. And she thanked alliance volunteers for their work throughout the summer.
"Their contributions of time and effort make it possible to collect and share this water-quality data and information," she wrote in a memo accompanying the test results.