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Let it Flow: The Case for Dam Removal Lori Anne Dolqueist, Esq. Partner Manatt, Phelps & Phillips, LLP www.manatt.com History From the earliest settlements, humans have diverted and stored water for a variety of uses. Sadd el-Kara (Egypt) – oldest known large-scale dam, dating from 2650 BC. Marduk Dam (Mesopotamia) – earth dam on the Tigris, lasted from 2000 BC to 13th century AD. Roman Dams (Spain) the first civilization to use concrete and mortar in their gravity dams around 100 AD. United States - The Jesuits introduced dam building to California as they established missions along the coastal regions. Progress Dam Pros and Cons PRO Serve a variety of functions, including flood prevention, water diversion and recreation. Significant part of nation’s water supply. Hydroelectric power provides approximately 7% of electricity in the United States. CON Modifies local habitats Affects plants, fish and wildlife. Influences the lives of those who live downstream. Safety and economic risks due to the possibility of dam failure. Aging The average age of a dam in the United States is more than 50 years old, and a small but significant number are a century old or more. By 2020, 70% of the total dams in the United States will be over 50 years old. Many dams are not expected to safely withstand current predictions regarding large floods and earthquakes. Managing aging dams is quickly becoming a principal focus of dam engineering Hazards In its Report Card for America’s Infrastructure, the American Society of Civil Engineers gave the nation’s dams a D grade. There are 14,000 high-hazard dams (where failure would result in loss of life) in the U.S., up from 10,000 just ten years ago. The estimated cost to repair the high-hazard dams is $21 billion. Also 12,000 dams are currently labeled as significant hazard, meaning a failure would not necessarily cause a loss of life, but could result in significant economic losses. Lake Dehli The dam failed on July 24, 2010 after a period of heavy rain. Around 8,000 people in downstream areas had to be evacuated. Flood damage to homes and businesses. Flooded the the city’s sewage treatment plant. Approximately $50 million in damages and $120 million in economic losses. Dam Removal Pros & Cons PRO Environmental benefits - restoring natural river flows, removing blockages for fish migration, re-establishing the river habitat, and improving water quality. Increased opportunities for recreation and tourism related to the restored river. CON Decreased property values. Damage to ecosystems that have evolved near the dams. Release of toxins in sediment. Issues Assessment of the dam’s uses, sedimentation, structural quality, and steps for restoring the river. Dam removal usually requires multiple regulatory permits, environmental review, and numerous safety precautions. These are multimillion-dollar projects and cobbling together funding can take years, even decades. The process of physical removal can vary because of the unique aspects of many dams and rivers. Even after affected parties agree that a dam should be removed, it can often take years (or decades) to determine how. “If you remove it really slow, one foot per year, you’d hardly notice the difference, but who wants to wait two hundred years to remove a twohundred-foot dam?” - Tim Randle, U.S. Bureau of Reclamation Brown River Dam Largest river restoration project in Michigan. Instead of gradual draining, water began rushing through the dewatering structure. The breach nearly drained the river above the dam. It caused flood-damage to more than 50 homes downriver, and deposited approximately 5000-7000 cubic yards of sediment downriver. Elwha River Restoration Project Largest dam removal project in U.S. history $350 million cost Removal of the Elwha Dam and the Glines Canyon Dam Includes new water treatment plant, wells, hatchery and wastewater collection Contested and periodically blocked for decades. Congress authorized the project in 1992, but it took two decades to get the money and logistical details in place. Elwha Progress In July 2011, the reservoirs behind both dams were drawn down. The Elwha Dam, closer to the river mouth, was removed first, beginning in September 2011 and completed in 2012. In April 2013, with two-thirds of the Glines Canyon Dam removed, the sediment overwhelmed the new water treatment facilities. Addressing this issue delayed completion of removal of the second dam until 2014. Salmon are moving into stretches of the river formerly blocked by the dam. San Clemente Dam Removal & Carmel River Reroute Largest dam removal project ever to occur in California Will remove the San Clemente dam and reroute a portion of the Carmel River. Began this summer and is expected to take three years and cost approximately $83 million dollars San Clemente Details The California Division of the Safety of Dams issued a safety order for the dam structure in the early 1990s, determining that the structure could potentially fail in the event of either earthquake or flood. Removing the dam is more expensive than buttressing, but addresses environmental issues. California American Water worked with agencies and other groups to develop a feasible approach. $49 million of the project costs will be funded by customers. An additional $25 million will come from the State through the California Coastal Conservancy. The remaining $10 million will come from federal grants and private donations. Conclusion As the nation’s dams continue to age, hundreds of communities across the country are struggling with decisions about how to deal with the cost to operate, maintain and repair these structures. For some, dam removal can be the most prudent choice by eliminating safety hazards, restoring the environment, and revitalizing the community. (Graffiti on Matilija Dam)