Pollution puzzler: Bacteria closes what should be Westport River’s cleanest section
The Westport River has seen shellfish closures before, but one declared two weeks ago due to pollution has observers both concerned and scratching their heads.
The culprit is high coliform bacteria levels typically produced by human or animal waste. Such pollution can contaminate shellfish, making it unsafe for people to eat.
Chris Leonard, Westport’s director of marine services said that a big part of what makes this event strange is the location.
“Although January is typically a time of higher bacteria counts, to have a high count coming through in what is supposed to be the cleanest part of the river, the area closest to the ocean that get the most tidal flushing, is concerning,” Mr. Leonard said. “It’s a sad state of affairs.”
The closure impacts two areas of about five acres of river, from near Charlton’s Wharf and Boathouse Row, near the harbor entrance, up the West Branch to Spindle Rock/Canoe Rock area (from the #14 buoy to near the #26 buoy).
“We’ve been close to the testing failure threshold in recent winters but this winter we have gone over,” Mr. Leonard added, significantly so in several testing places.
In bitter cold just after sunrise Monday, Mr. Leonard and Greg Sawyer, senior aquatic biologist with the Massachusetts Division of Marine Fisheries, set out in the Westport Shellfish Department skiff for followup tests to the initial routine tests that revealed the problem.
Mr. Sawyer said his plan was to take water samples from 14 locations “to see if we can zero in at all on a possible source … and if so see if we can figure out a cause.” He also wants to see if conditions have improved since the earlier tests.
Those tests revealed improvements in some places but also some trouble spots, he said later. He planned to return for more tests this week.
Mr. Sawyer agreed that such readings are odd, given that this is “a high wash area” near the open waters of Buzzards Bay.
And he said there is a “usual suspects” list anytime coliform bacteria is discovered is such a waterway — that list includes failed septic systems, birds, farms and road runoff.
Although he hopes Monday’s tests shed more light on the cause, Mr. Leonard’s early suspicions focus on birds — geese, ducks, gulls, swans …
“This has been an unusually mild winter and there has been a humungous bird presence,” Mr. Leonard said. Maybe the warm weather “has been messing up migratory patterns.”
He said he believes Westport would benefit from some sort of annual bird census that might help link bird numbers to bacteria counts.
While, septic septic systems remain a possibility, he said that a good number of homes near the water in this part of the river are “not in use at this time of year.”
Mr. Sawyer said he, too, thinks the bird theory is plausible — he’s seen it happen elsewhere. As for runoff, that seems unlikely since water in the upper West Brach tested cleaner.
The Westport Fishermen’s Association is devoted to protecting the river’s water quality — “That’s how it got its start,” said the group’s president Jack Reynolds.
While he doesn’t doubt that birds may contribute to the situation, “I think it is not as simple as that.”
“I’m sure that birds do add to it, however I don’t think the birds bring it over the tipping point,” Mr. Reynolds said.
Because it has been a warm winter with little ice, “the birds are more spread out, not all concentrated down by the entrance where there is open water as in recent years.”
And he also wonders why water tests at Cockeast Pond, “which is loaded with birds,” show almost no coliform bacteria.
Mr. Reynolds tested it himself recently, making sure do to so after low tide to eliminate any chance of water running from the river up the Herring Ditch into the pond. “The (coliform bacteria) count was zero … we’ve never gotten a zero.”
Other options for shellfishermen
While “we have quahogs and scallops in these waters,” Mr. Leonard said the closed area is typically not harvested that much by shellfishermen at this time of year.
The commercial rakers mostly head over to the quahog transplant beds that open in the winter months at the lower end of the East Branch, he said.
Mr. Sawyer hopes that an update to the closure can be provided sometime this week.