Herring make a comeback in South Shore rivers, but now face new threats 12-1-17

Herring make a comeback in South Shore rivers, but now face new threats

By Neal Simpson
The Patriot Ledger

Posted at 1:39 PM
Updated at 3:16 PM

Years of habitat restoration work means thousands of herring are now swimming up the North River from Scituate to Pembroke -- only to have their offspring sucked into Brockton's water supply.

After years of building fish ladders, tearing down dams and cleaning up the rivers of the South Shore, environmental advocates celebrated a milestone last spring as some 300,000 herring – more than twice as many as two years earlier – made the long journey up the North River from Scituate to Pembroke to spawn.

Only months later, there was bad news: roughly 2,500 dead herring had washed up on the shore of Silver Lake in Kingston.

It wasn't the dead fish that concerned Samantha Woods, executive director of the North and South Rivers Watershed Association, but that they were in Silver Lake at all. Herring have no natural way to reach the lake, which has been cut off from the Jones River for years; Woods says they could only have been sucked out of ponds in Pembroke when the city of Brockton opened a culvert in Pembroke to replenish its water supply. Once in the lake, the fish were trapped.

"Are we going to let them die after spending all this time, money and energy to restore their spawning habitat?" said Woods, who has helped organize a petition calling on Brockton to change its water management practices.

Herring habitat advocates say the dispute over water use at Silver Lake is only one example of the challenges they face, even as they begin to see success in restoring the state's once-decimated population of river herring. Now, two watershed groups and Pembroke's fishery commission are demanding Brockton reduce its century-old dependence on Silver Lake drinking water, saying it will become more harmful to marine life as the city's population grows and climate change makes rainfall less reliable.

Despite their fears, advocates acknowledge that herring numbers in some rivers have been so strong in recent years that state officials have considered easing a ban on herring harvesting, once a popular past time in towns like Weymouth and Plymouth. But the herring population has continued to fall in other rivers, raising concerns among state officials.

"It's been a mixed result across the state," said Brad Chase, a biologist with the state's Division of Marine Fisheries. "What we're seeing is the runs Cape Cod and south are either holding their own or declining since 2014, whereas runs from the South Shore northward tend to do a little bit better."

River herring, once plentiful in New England's coastal rivers, have been on the decline for more than two centuries as rivers have been clogged with dams, and coastal waters have become a hunting grounds for trawlers that scoop them up in nets while seeking larger fish. Advocates have worked for years to restore herring river habitats, some of which have been closed to spawning since pre-Colonial times when some dams were built. But those efforts took on a new urgency around 2005 when herring counts dropped precipitously, prompting state officials to ban all herring harvesting.

On the South Shore, those efforts have been spearheaded by the North and South Rivers Watershed Association, which works in 15 towns from Hingham to Duxbury and Abington to Marshfield. Along with town officials, state agencies and other organizations, the association has helped rebuild fish ladders and remove dams and culverts in Scituate, Norwell, Hanover and other towns.

Despite those efforts, 63 dams remain in the watershed, according to the association, and advocates say the resurgence of the herring population in some rivers has highlighted other problems, particularly around water management by cities and towns that rely on the region's ponds and rivers for drinking water. Those issues are expected to become even more urgent as the human population – and demand for drinking water – continue to grow.

Herring in Pembroke make their way to spawning habitat this past April. — Greg Derr / The Patriot Ledger
Recent herring restoration projects
September 2017: The removal of Scituate's Hunters Pond Dam is completed, allowing herring to reach Bound Brook for the first time in decades.

June 2017: Crews begin work on a $1 million project aimed at reinforcing Great Pond Dam in Braintree and building a fish ladder that will allow herring to reach spawning habitat

February 2017: A study is completed on the feasibility of removing Braintree's Armstrong Dam, a major obstacle for herring seeking to reach the spawning habitats in the Great Pond Reservoir.

December 2016: Hanover's Tack Factory Dam on Third Herring Brook is removed, allowing eight miles of the brook to flow freely into the North River for the first time in since the 1600s.

Drinking water or habitat?

In Kingston, the dispute over the use of water in Silver Lake dates back to the late 1800s, when Brockton gained water rights to use the lake to support its growing population. In the 1960s, when the region was going through a drought and Brockton was struggling to get enough water, it got state approval to begin diverting water from Furnace Pond in Pembroke into Silver Lake.

Advocates say that arrangement, which today allows Brockton to divert up to 10 million gallons a day from Furnace Pond during certain times of the year and under certain conditions, depletes streams that feed into the North River and sucks juvenile herring into Silver Lake before they have a chance to make it down-river and out to sea. They say the 2,500 fish found dead this fall only hints at the unknown number of herring trapped in the lake with nowhere to go.

A petition circulated this month by the North and South Rivers Watershed, Jones River Watershed and Pembroke Fisheries Commission calls on Brockton to begin addressing the problem of diverted herring by installing new screens that would help prevent the fish from being sucked into the lake – something Pembroke says it first requested five years ago. There's already a screen in place, but Pemboke selectmen chair Bill Boulter said it's not stopping the adult herring he sees slipping though it when water is being diverted into Silver Lake.

"They've (stopped diverting Furnace Pond water) when we've called, but we can't be here 24-7," said Boulter, who also sits on the town's herring fisheries commission.

The petition also urges the city to reduce its dependence on Silver Lake for drinking water by implementing water conservation programs and turning to other sources for water, either by relying more on a little-used salt water desalination plant in Dighton or by joining the Massachusetts Water Resources Authority, or MWRA, which provides water for 51 cities and towns, including several on the South Shore.

No easy answers

Water access is already a divisive topic in Brockton, which currently pays around $6.5 million a year for the desalination plant but rarely uses it. Mayor Bill Carpenter has proposed buying the plant – which serves as an emergency back up for Silver Lake – but some city councilors have balked at the $78 million price tag. The city has been told that tapping into the MWRA's pipes could be even more expensive.

Carpenter was out of town late this past week and his chief of staff, Darren Duarte, did not return calls for comment.

The urgency of water management issues around Silver Lake came into stark relief for many environmental advocates in 2016, when a historic drought lowered Silver Lake to a level more than 8 feet below capacity and dried up many streams. Volunteers were forced to carry herring by hand to streams and ponds that still had water.

Ecologists are waiting to see what effect the drought will have on herring counts in two years, when many of the herring born in 2016 will return to the rivers to spawn. Many environmental advocates said they fear what will happen if droughts become more common.

"We're living on the brink all the time," said Alex Mansfield, ecology program director for the Jones River Watershed Association.

Chase, the state marine fisheries biologist, said water management issues like those facing Brockton are found in nearly every coastal watershed in Massachusetts, as growing demands for drinking water runs up against the limits of watershed capacity. But he said the interests of providing drinking water for humans and leaving enough behind to support marine life don't have to be at odds.

"There are cases where you can actually make it work," he said.

In Scituate, for example, the North and South Rivers Watershed Association has a partnership with town officials it says has helped bring herring back to parts of the First Herring Brook, which serves as the town's drinking water source. The association says an irrigation restriction adopted by the town has saved over 300,000 gallons a day and raised stream levels enough to allow herring to return to parts of the brook where they hadn't been seen in decades.

"We believe a healthy watershed is healthier for the human population as well as for the littler creatures," said interim Scituate Town Administrator Al Bangert.