WOOLWICH — Trevor Hunt, superintendent of the Bath Water District, sat on the edge of the concrete fish ladder in Nequasset Stream on Wednesday staring into the churning water below.

Squinting against the bright, midday sun, he watched three silvery-gray fish lurk in a calm eddy, but he stayed alert.

“If you hear a sound that changes — a “di-di-di-di-di” — look down really quick,” he said. “It’s about to go up.”

Sure enough, a lone alewife made its stand, bracing itself against the sluice of river water and wriggling its way up the plywood chute until … it was knocked back into the bubbling pool below.

Each spring, seagulls line the roof of the Woolwich Meetinghouse and osprey and bald eagles soar over Nequasset Stream, representing just a few of many creatures who welcome alewives back to the Woolwich Fish Ladder.

The fish live largely out at sea, but are anadromous, meaning that each spring the adult alewives swim upstream into fresh water — like Nequasset Lake — to spawn. Most adults and juveniles then head back to sea between July and October.

Alewives are featured prominently on the Woolwich seal and town letterhead, and rightfully so. The community is one of only 19 in the state to maintain a commercial alewife fishery, said Alicia Heyburn of the Kennebec Estuary Land Trust.

“It’s the longest continuous industry in the town,” Debbie Locke of the Woolwich Historical Society, noted.

For generations, the Lilley family has held the town’s only municipal alewife harvesting license. Bill Potter, chairman of the Woolwich Fish Commission, said Herb Lilley harvests the fish Thursdays through Sundays, dropping a net into the stream as the silvery fish rush through.

Their taste doesn’t appeal to everyone — Potter wrinkled his nose and mentioned “the bones” — but to a variety of other fish, including bass, brown trout and salmon, as well as animals including seals, whales, mink, fox and raccoon, among others, alewives are an eagerly awaited delicacy.

And for local lobstermen, there’s no better bait.

The Bath Water District owns the dam and fish ladder, and is responsible by law for ensuring that the fish can pass easily over it each year to spawn.

For years, the water district and KELT have worked together to ensure that alewives can experience a smooth passage upstream, according to Hunt.

But on Wednesday, sandbags lined the base of the concrete structure, and murky water spurted through cracks and holes all over the crumbling fish ladder. The decrepit fishway is in such disrepair that he worries it won’t last another year.

“We’ve been limping along,” Hunt said. “There are various patchworks over the years, but it takes a beating.”

So last year, Hunt said, he decided to make restoring the ladder a “fairly high priority, or we’re going to lose it.”

He approached KELT to work together to find grant money and other funding for the project, which Heyburn expects will cost several hundred thousands. Other interested parties, including the Woolwich Fish Commission and the town of Woolwich, also signed on.

Now, both look toward restoring the historic structure by next summer.

“This time next year, we’ll be preparing and waiting for the fish to go into the lake,” Hunt said. “Then we’ll close off the fishway, rebuild (the ladder) and have it ready for the fish to go back. Until then, we must keep this one limping along.”

Beforehand, though, KELT has undertaken the first visual count of the alewives, to see just how many of the fish traverse the river each spring.

On Wednesday, Heyburn took a two-hour turn on watch — and was rewarded as a fat alewife jumped from the churning waters of the top pool in the ladder, struggled up the plywood plank — and then was swept back into the eddy.

No click during that watch, but that didn’t lessen the excitement as iPhones snapped photos of the first almost-official fish of the year.

“Only the most incredible athletes make it,” said Heyburn said.

bbrogan@timesrecord.com

How to help

• The Kennebec Estuary Land Trust seeks volunteers to help take a visual count of alewives as they swim up through the Nequasset fishway between now and June.
• To sign up, visit www.kennebecestuary.org, the Nequasset Fish Ladder Restoration Project page on Facebook, or email aheyburn@kennebecestuary.org.