Looking to Avoid Costly Maintenance and Restore Ecosystems, Organizations are Tearing Down Dams
Glines Canyon Dam in Washington state, USA, mid-demolition
Across North America and parts of Europe, dams are coming down. Both continents are in the midst of a wave of dam decommissioning and removal projects driven by the desire to eliminate costly maintenance and restore damaged watersheds and fisheries.
Between 2006 and 2014, the United States alone removed 548 dams—nearly twice the number of dams removed in the prior 10 years—with an additional 62 removed in 2015. Removal projects have also multiplied in recent years across the U.K., France and Spain. But no matter how small the dam, removal can quickly grow complicated as teams interact with dam owners, local conservation groups and the general public, and contend with environmental and cost risks.
With budgets typically high—removal of a small dam just 10 feet (3 meters) high can cost more than US$100,000, while larger projects can exceed US$1 billion—teams are under pressure to hold down costs. The best way to do so is to invest significant time gathering “as much information as possible from every possible source,” says Lisa Hollingsworth-Segedy, associate director for river restoration for the conservation group American Rivers, Pittsburgh, Pennsylvania, USA.
“As engineers and project managers, we often don't deal with the public particularly well.”
—Andrew Hughes, PhD, Atkins, Surrey, England
Over the last eight years, Ms. Hollingsworth-Segedy has managed 45 dam removal projects; the average length was about three years. (Dam removal project sponsors include nonprofit and private-sector organizations as well as governments.) She starts by having the team thoroughly research the history of the dam, other structures within the waterway and any restoration efforts already underway in the surrounding ecosystem and community. She also identifies any possible environmental factors that could impact the removal process, from silt behind the dam to pollutants upstream. A full understanding of the history and environmental conditions is crucial to avoiding problems, like seasonal weather conditions shutting out demolition crews.
But even with proper planning, a number of factors can trigger delays, Ms. Hollingsworth-Segedy adds. These can include problems with funding, documenting nearby endangered species and obtaining permits required by regulatory agencies.
One stakeholder project managers shouldn't underestimate during the planning phase is the public, says Andrew Hughes, PhD, director of dams and water resources for Atkins, a global design and engineering firm. (He's also the chairman of the British Dam Society, Surrey, England.) As soon as a preliminary removal plan is available, Dr. Hughes recommends reaching out to local environmental and community groups to listen to concerns and educate them on the removal process and its impact. Getting the public on your side early is especially valuable for projects on strict timelines due to weather patterns or flood risk conditions in the area, he says. Those factors can limit when demolition work can occur, so avoiding delays due to stakeholder opposition is key.
“You've got to provide information and hold and attend public meetings,” Dr. Hughes says, noting that formal planning and approval processes vary from country to country. “You've got to engage the public all the way through,” even during early initial surveying periods when project managers are still defining the scope.
“As engineers and project managers, we often don't deal with the public particularly well. We come over as engineers rather than human beings,” he says. “Engaging with the public, I think, is a thing engineers have to learn.” —Christina Couch
Hydropower: Still in Demand
As dams come down in some parts of the world, they're going up in others. Here are three of the largest projects underway or recently completed—all touted to boost power supplies in developing countries.
Location: Inga Falls waterfall, Democratic Republic of Congo
Budget: US$80 billion-US$100 billion
Why: The dam is projected to generate 40,000 megawatts of electricity—the equivalent of 20 large nuclear reactors.
Challenge: Public opinion. The project has come under fire from conservation and human rights groups concerned that the dam is being built without proper environmental surveys and will displace 60,000 people.
Location: Siquirres, Costa Rica
Budget: US$1.4 billion
Why: This 130-meter (427-foot)-high dam, completed in September, is projected to generate 305.5 megawatts of electricity, enough to power 525,000 homes.
Challenge: Environmental impact. Reservoirs created could interrupt animal and fish migration patterns, reducing biodiversity. To mitigate the issue, the Costa Rican government worked with conservation groups to design the dam in environmentally friendly ways.
GRAND ETHIOPIAN RENAISSANCE DAM
Location: Blue Nile River, Ethiopia
Budget: US$4 billion-US$5 billion
Why: The 170-meter (558-foot)-tall dam is projected to generate up to 6,000 megawatts of power, more than tripling Ethiopia's electricity supply.
Challenge: Design. International teams of engineering and hydrology experts have questioned the ability of dam design plans to mitigate safety and environmental risks.
PM NETWORK DECEMBER 2016 WWW.PMI.ORG
DECEMBER 2016 PM NETWORK