Easton Fish Ladder

Attraction Water

Bill McWha [email protected] 860-778-7167 Easton Dam at present. Water flowing over the entire face of the dam. This much water across the dam, serves only to confuse the fish that are trying to find upstream passage. Marginal flow from the ladder, no flow next to the ladder. Connecticut , Holyoke Dam Fish Lift. At bottom, is the entrance to fish lift. , Holyoke Dam. Spillway entrance to fish lift. This lift passed 158,812 in 2007. I would estimate that this entrance passed 60,000 shad.

4 FEET Face of the Holyoke Dam with it’s Bridgestone bladders inflated. Almost all attraction water has been directed to the fish lift side of the dam. Some water is spilled on the other side for an . Obermeyer Hydro, makes inflatable crest gates of various sizes. They are a direct competitor of Bridgestone Rubber. ESSEX DAM or GREAT STONE DAM LAWRENCE,MA.

Putting a hard top to it

After two severe in two years, a Merrimack dam gets a makeover By Tim Wacker, Globe Correspondent | September 27, 2007 LAWRENCE - For years, whenever waters overwhelmed the plywood flashboards atop the Great Stone Dam on the Merrimack River, boaters did less boating, the power plant at the dam generated less power, and fewer fish made it past the 150-year-old edifice to further upstream.

But things are going to get better - or so everyone hopes. Following two severe floods in the past two years that, among other consequences, cut into its revenues, the hydroelectric power company that owns the dam decided enough is enough. Construction crews are now working to fix the problems permanently by replacing the old flashboard system with a modern metal structure that can better regulate the Merrimack's levels. "It's something that's always been talked about between us and the state," said Julie Smith-Galvin, spokeswoman for Enel North America, the Italian power company that owns the dam. "After the [last] flood, it just became more apparent that it was necessary." The work involves replacing the 5-foot-tall plywood flashboards atop the dam that have been used for decades to help raise the level of the river upstream. But the flashboards are also prone to washing away during floods, letting water rush over the top of the dam for weeks, even months, until the river drops low enough for repairs to be made. Enel North America is topping the structure with a pneumatically controlled series of retractable metal walls called a crest gate. The $3.5 million installation is expected to prevent the prolonged rush of water over the dam that often happens during crucial spawning migrations for shad, alewife, herring, and , hindering the fishes' progress as well as production of electricity. "If the fish are delayed in their spawning run for too long, they will spawn below the dam, where they don't have the best habitat," said Joe McKeon, who runs the central New England fish hatchery program for the US Fish and Wildlife Service. "We had almost no American shad come through to spawn in 2006," he said. "And that means another generation of shad that won't return to spawn a few years from now. It's a cyclical problem." When the flashboards give way during floods, as they did last year and the year before, water washing over the dam confuses fish heading upstream. They can't make their way to a fish lift at the barrier - their only means of getting upstream - to which they are normally attracted when the flashboards are doing their job. While the new crest gate will not eliminate the spillover problem during floods, McKeon said, it will shorten the duration of the problem. That means more fish making their way past the dam - great news for anglers, some of whom have volunteered at the fish lift for years trying to improve the spawning run. We've counted fish as they come in, we've cleared debris from the lift, we've done whatever we can," said Gerry Crow, president of the Merrimack River chapter of Trout Unlimited, a national organization. "But those flashboards have always been a problem," Crow said. "There are always at least one or two blown out. If this work is supposed to improve that, we're all for it." Recommendation : Install Obermeyer Gates on the south side of the dam 3 to 4 feet in height. These gates when fully extended, would be flush with the top of the dam. They would be lowered in the spring to provide attraction water near the ladder entrance. Easton Dam Fish Ladder

Upstream Passage Modifications Easton Dam ladder at present.

Shad will stall in this turn pool.

2½ Feet Lehigh River

MINIMAL TO ZERO FLOW OVER DAM IN THIS AREA

Obermeyer gate partially deflated Easton Dam

Obermeyer gates fully deflated for MAX. flow.

Obermeyer gate submeged at entrance to .

Delaware River Flow

THIS APPLICATION CAN BE USED AT ANY LOW HEAD DAM Proposed Location: Lehigh River Modular Fish Passage Facility

Delaware River

Lehigh River Lehigh River

BASIC STRUCTURE FOR TESTING DIFFERENT FISH PASSAGE CONCEPTS

Cameras for Accurate Entrance and Exit Counts

Delaware River Camera

Lehigh River

Baffles to slow down water. Camera

Obermeyer Gate Crowder Gates

Delaware River Camera

Lehigh River

Baffles to slow down water. Camera

Crowder Gates

Delaware River Camera

Lehigh River Sluice Gate for Additional Flow When ‘Little Falls’ Fishway is Installed.

Camera

‘Little Falls’ style fishway

Delaware River Camera

Lehigh River

Serpentine Ladder

Camera

Delaware River Camera

Lehigh River

Denil Ladder

Camera

Denil Ladder

Delaware River