Alison Bowden, director of the Conservancy's Freshwater Program in Massachusetts
By Alison Bowden
I'm driving alongside the Connecticut River when I spot a bald eagle perched in a tall white pine, watching the tumbling water for fish. What this eagle can probably sense is that, just down the road, the water crawls to a stop. The Holyoke Dam splits the river there, rearranging the flowing waters that have choreographed aquatic life cycles for millennia — including those of the fish that the eagle relies on for food.
Of course, there's another side to the story. This dam also has capacity to generate 383,000 megawatt hours per year of renewable electricity, enough to power about 53,000 households.
At a time when energy demand is skyrocketing and fossil fuels are rapidly propelling climate change, the hydropower dilemma continues to confound conservationists.
But are we missing something right beneath our feet?
Imagine the billions of gallons of water that are gushing right now through the labyrinthine network of pipes, tanks, reservoirs and water treatment plants already in place to cleanse and deliver your drinking water.
Now imagine we could harness that water for power: Clean water and clean energy — generated at the same time, using the same infrastructure.
Just a pipe dream? No. In fact it's already happening in Boston.
The Massachusetts Water Resources Authority (MWRA) transports an average total of 220 million gallons of water a day from the Quabbin and Wachusett Reservoirs — largely by the force of gravity — through a system of more than 100 miles of tunnels and aqueducts.
They capture the energy from this falling water at their Deer Island Wastewater Treatment Plant and two other locations within the water system, and they recently received a grant to install a turbine at a fourth location.
Individually, these conduit turbine projects generate nowhere near the same amount of power as those in, say, Hoover Dam. But enough smaller turbines scattered throughout the system could deliver great results.
When I call Pamela Heidell, policy and planning manager at the MWRA, her excitement about this project's potential is obvious.
"Using the water that's flowing through our distribution system just makes sense," says Heidell. "We're working with the resources we already have to produce clean, renewable energy."
Instead of reducing the built-up water pressure with valves, MWRA has received a grant from the Massachusetts Technology Collaborative to install a hydro-turbine that will generate 1,200 megawatt hours per year — much less than the Holyoke Dam, but comparable with most dams in state.
What's more, some of the money earned from MWRA's hydropower projects is funneled into watershed protection efforts.
I look at many hydropower proposals — usually for dams — and I'm immediately struck by the environmental impact section of this one. Does the project lie within in a floodplain? No. Does it disrupt fish passage? No. Rare species? No impact.
When it comes to energy infrastructure, these two words are music to an ecologist's ears.
As urbanization expands, water-generated energy will be an important piece of a sustainable energy solution. And one of the best things the Conservancy can do is continue its work with dam operators to manage dams in ways that work with nature's processes.
But the reality in many places is that river power has been exploited to its limits.
Meanwhile, the developing world is busy reenacting some of our country's worst mistakes. This time, the stakes are even higher: Many of the thousands of current dam-building projects around the world could devastate fisheries, disrupt floodplains and displace millions of people.
For both economic and environmental reasons, we must continue to look for energy innovations that use infrastructure already in place and make better use of the water we've already collected.
After all, isn't that the very meaning of "conservation?"May 31, 2011
is director of The Nature Conservancy's Freshwater Program in Massachusetts. She works closely with governments, water resource managers and conservation partners to assess the health of rivers, restore connectivity and natural flow and integrate freshwater and marine conservation strategies. Bowden holds an M.S. in water resources from the University of New Hampshire and a B.A. in environmental science from American University.