Collaboration

A monthly column in the Monadnock Ledger-Transcript.

Tuesday, January 27, 2015

Some Dams Need to Go



Film DamNation Feb. 5 at Keene State College shows the need for dam removals.

North Branch of the Contoocook River flows over the
dam at Robb Reservoir in Stoddard.
Follow any stream around here and sooner or later, it’ll be blocked by a dam.
If that stream itself isn’t held back by a dam, the river it feeds is jammed with a dozen or more dams, blocking fish, altering natural flow regimes and sometimes putting downstream communities at risk.

Every river and major tributary in the Monadnock Region is dammed: The Contoocook River and its tributaries are full of dams – 279 to be exact – from Jaffrey through Peterborough, Bennington, Hillsboro and all the way to Penacook. The main stem alone has 19 dams. The Contoocook’s recipient, the Merrimack River, is choked with dams all the way to the ocean. 

Many of these dams are a legacy of the Industrial Revolution, providing power that built our communities since the late-1700s. While a handful of the Contoocook River dams are generating power or protecting towns from floods (like MacDowell Dam), most are simply holding back water and blocking fish and other species from moving up and downstream.
 
Freeing Rivers is Catching On

Some of these obsolete old dams need to go. And in the coming years and decades, we’ll watch our rivers running a little more freely – as they should be. Not all of the dams will go, but some of them surely will, saving owners money for upkeep and helping fish reach long-blocked habitat.

Since the 1999 removal of the Edwards Dam from Maine’s Kennebec River, the notion of removing dams has been gaining traction around the country. In fact, two of the country’s biggest dam-removal projects are happening now – one on Washington’s Elwha River and the other in Maine. 

On Maine’s Penobscot River, a coalition of agencies, organizations and the Penobscot Indian Nation have raised millions to purchase dams, remove two big ones and build a bypass around another. They’ve done this while maintaining or increasing hydro-energy production. Sea-run fish like shad, herring, sturgeon and eel are already returning to habitat that had been blocked for over 150 years.

What’s happening on the Penobscot is nothing short of an incredible and long-overdue success story. While the Penobscot is a huge and complex river, its rebirth sets an example for many other rivers, here in New Hampshire and beyond.

DamNation: Film & Panel in Keene

The legacy of damming America’s rivers is explored in a new documentary, DamNation, which will be shown Feb. 5, 7 p.m., at Keene State College. Focusing on big, Western dams, the documentary shows the toll dams have taken and offers hope for restoring rivers. The film will be followed by a short panel discussion, touching on efforts to remove dams from the Connecticut and Ashuelot rivers.

New Hampshire has more than 4,800 dams, many built over 100 years ago, helping to drive the economic engine that developed the state. Some of these dams create our local iconic and treasured places, destinations for recreation. Spoonwood Pond and Nubanusit Lake in Nelson and Hancock, for instance, are artificial impoundments, created to regulate water supply for the mills in Harrisville. Even Willard Pond is an artificial impoundment.

A smaller number of dams provide fire protection (an estimated 8 percent of dams statewide). And some dams provide hydro-power (about 5 percent of dams statewide), water supply (3 percent), and flood control (2 percent). 

Old, Obsolete and Ailing Dams

That leaves quite a few dams that are doing little, other than holding back water and blocking fish. And some of those dams are unsafe. The state Dams Bureau classifies more than 300 dams as high or significant hazards, threatening property or lives downstream should they fail. Good candidates for removal.
And like our own aging population, the older those dams get, the more work they need. 

Of New Hampshire’s 4,800 dams, nearly 2,000 are privately owned, 358 are owned by local governments, 255 are state-owned. 

The 87 dams owned by the N.H. Fish and Game Department illustrates the predicament. Many of Fish and Game dams were built decades ago using federal aid funds to help restore waterfowl, like the dams at Carpenter’s Marsh in Hancock and Robb Reservoir in Stoddard. These dams helped some waterfowl species, arguably to the detriment of other species, like wood ducks.
But those dams also have harmed local fish populations, especially Eastern brook trout, by blocking habitat that they need to satisfy life cycles. 

In the coming years and decades, those dams will present Fish and Game with some hard choices. The dams will start showing their age. Some will pose serious risks to downstream places. The agency will face the choice of spending large sums of scarce dollars to improve and maintain them or spend a similar amount to remove them altogether. It’s a choice that pits waterfowl interests (at least some waterfowl species) against the interests of fisheries.

On the Seacoast, those interests and divisions are sharp, where runs of native herring, eel, shad and sea-running brook trout hold great promise with the removal of dams. And some of those dams are starting to come out, as they should.

Healthy Rivers Run Free

Fish and public safety aren’t the only good reasons to remove old dams. For the thousands of years that our rivers have run free, they’ve occasionally flooded, creating floodplains and floodplain forests. Dams, agriculture and development have drastically some of these floodplains. 

These floodplains can protect communities from flooding. The experience of Middleboro, Vermont, during Tropical Storm Irene convinced many that floodplains can serve as a natural way to protect downstream communities from potentially devastating impacts of floods.

Dams will long play a role for providing flood and fire protection, energy and recreation. Some can be fitted with innovative up- and downstream fish passage. Dam-owners can also tweak operations to help mimic natural flows. Not all dams need to go. 

But some should be removed. Owners who make that choice may find a surprising number of partners and funding to help remove them. 

DamNation will beshown February 5, 7 p.m., at the Putnam Theatre, Redfern Arts Center, Keene State College. Following the screening will be a panel discussion with: Kim Lutz, Connecticut River Program director for The Nature Conservancy; Robert King, president of Ashuelot River Hydro, Inc.; James Gallagher, administrator of the N.H. Department of Environmental Services Dam Bureau; and James Rousmaniere (moderator), retired editor of the Keene Sentinel. The event is sponsored by The Nature Conservancy and KSC Film Society.

Eric Aldrich writes from his home in Hancock. Reach him at ericadine@gmail.com.