The High Cost of High-Hazard Dams

ASCE-report-cardIt is well known that our nation’s infrastructure is in desperate need of repair or replacement. In fact, the American Society of Civil Engineers (ACSE) 2017 Report Card has given our country’s infrastructure an overall grade of D+. Dams are a part of that critical infrastructure, and they have received an abysmal D grade from ASCE. We have over 90,000 dams in our country, and the average age of these dams is 56 years old. Considering that dams built 50 years ago were not designed for current standards and usually have inadequate spillway capacity, these numbers are concerning.

Even more alarming, America has nearly 15,500 high-hazard dams, with over 2,170 of these being deemed deficient. A dam is rated high-hazard when dam failure could result in the loss of human life, and deficient when it is at serious risk of failure. A deficient, high-hazard dam is a tragedy waiting to happen. Also, considering the estimated cost to repair these deficient, high-hazard dams is almost $45 billion, it is apparent that we have a dam crisis on our hands.

About Dams

Lake Mead, impounded by the Hoover Dam, is one of the most popular vacation spots in the country.

Dams provide significant economic and social benefits to society, including flood control, water storage, irrigation, debris control, and navigation. In addition, around 3% of our nation’s dams provide hydroelectric power — a clean, renewable energy source — accounting for 35% of our country’s renewable energy and 10% of our total power needs. And, of course, the most frequent function of dams is recreation. Dams impound eight of the top ten most popular vacation lakes in the United States, accounting for millions of tourist dollars and some of our country’s most beautiful and enjoyable areas.

mill-river-dam-flood
The Mill River Dam collapse was the first manmade dam disaster and one of the worst of the 19th century. On May 16, 1874, the Mill River Dam in Williamsburg, MA failed, killing 139 people and wiping out four towns in western Massachusetts within one hour.

Catastrophic dam failures have occurred in the United States for well over a century, resulting in the deaths of thousands of people and causing millions of dollars in damages. This year, we narrowly avoided a disaster when California’s Oroville Dam stabilized after threatening to fail. During the crisis, over 188,000 people were displaced due to mandatory evacuations of the area. Although the Oroville Dam crisis thankfully ended without loss of life, the cost to repair the spillway is estimated to be $275 million. In 2003, the Silver Lake Dam in Michigan failed, causing approximately $100 million in property damages and putting over a thousand miners out of work. In 2004, the Big Bay Lake Dam in Mississippi failed, destroying 48 homes and seriously damaging 53 others. In 2006, the Ka Loko Dam in Hawaii failed, killing seven people and releasing nearly 400 million gallons of water, causing significant property and environmental damage.

dam-map-ma
Click on the image for an interactive map of dams in Massachusetts.

High-hazard dams are cause for concern in every state in the nation. In Massachusetts, 1,453 dams are included in the National Inventory of Dams, 333 of which are high-hazard. Of those, about 50 are classified as “poor” or “unsatisfactory” and in urgent need of repair. If any of these dams were to fail, there is a high likelihood that there would be a loss of human life. Dam failure is most frequently caused by overtopping, accounting for 34% of all dam failures. Causes of overtopping include inadequate spillway design, blocked spillways, settlement of the dam crest, and floods exceeding dam capacity. Other causes of dam failure include foundation defects such as slope instability and settlement (30%); piping, resulting in internal erosion caused by seepage (20%); and other causes including structural failure of materials, settlement and resulting cracking, poor maintenance, and acts of sabotage (16%).

Safety Programs

oroville-dam-damage
Draw down and cut off of releases from the damaged spillway at Oroville Dam. Taken on Feburary 27, 2017. Dale Kolke/California Delpartment of Water Resources.

The National Dam Safety Program (NDSP) was signed into law in 1996. NDSP was established to improve safety and security around dams by providing assistance grants to state dam safety agencies to assist them in improving their regulatory programs; funding research to enhance technical expertise as dams are built and rehabilitated; establishing training programs for dam safety inspectors; and creating a National Inventory of Dams. Every state in the nation excepting Alabama has a dam safety program, and 41 states also have Emergency Action Plan (EAP) requirements. A detailed and up-to-date EAP is critical to a successful dam safety program for high-hazard and significant-hazard dams. States without EAP requirements are Alabama, Georgia, Illinois, Iowa, Kentucky, North Carolina, Vermont, Wyoming, and — believe it or not — California.

Unfortunately, about one-third of our nation’s high-hazard dams lack an EAP. In addition, state dam safety programs are sorely underfunded and understaffed, and many of our nation’s deficient dams are not being repaired or rehabilitated in a timely manner. Why? State dam safety programs provide the inspection, permitting, recommendations, and enforcement authority for 80% of our nation’s dams, yet the average ratio of dams to dam safety inspectors is 207:1. Also, about two-thirds of our nation’s dams are privately-owned. Without enforcement of repair recommendations, some dam owners simply choose not to sink any money into their deficient dam.

kaloko-dam
The Ka Loko Dam breach in Hawaii resulted in the deaths of seven people, including a pregnant woman and a toddler.

For example, the Ka Loko Dam in Hawaii was privately-owned, and owner James Pflueger was sentenced to seven months in prison in exchange for a plea of no contest to reckless endangering. By entering the plea, prosecutors agreed to drop the seven counts of manslaughter. But admittedly, the dam failure was the result of a series of negligent events. The State of Hawaii, like most states in the nation, had a shortage of dam inspectors, and the Ka Loko Dam had not been adequately inspected. Also, Pflueger performed unpermitted construction activities at the dam, including grading and filling in the spillway. The County of Kauai ordered Pflueger to cease and desist all illegal grading operations, yet Pflueger ignored the order with help from then-Mayor Maryann Kusaka, who served as mayor of Kauai from 1997-2004. He also knew that there was seepage at the dam prior to the failure.

Key Issues 

The Wachusett Dam in Clinton, MA is a high-hazard dam, rated in satisfactory condition.

Clearly, the Ka Loko Dam failure was due to gross negligence and was completely avoidable. To avoid similar tragedies in the future, all of the key issues facing our nation’s dams should be addressed. First and foremost, our country needs to invest in infrastructure and to prioritize funding of dam safety programs. It is imperative that dam safety agencies have adequate personnel and resources to enforce inspection, repair, and rehabilitation recommendations. Also, since two-thirds of our nation’s dams are privately-owned, lack of funding for private dam upgrades is a huge problem. Adequate maintenance and rehabilitation of dams is costly, ranging from thousands to millions of dollars, and many private owners simply cannot afford these costs. Because of the high risk of high-hazard dams, our nation must prioritize funding assistance and loan programs to both public and private owners. It is also crucial that high-hazard dams have an up-to-date EAP, including action plans as well as notification and evacuation procedures, so that authorities are prepared and residents living downstream of the dam are protected. And speaking of residents, public outreach and awareness may be the most critical component of dam safety and awareness. The typical American citizen has no understanding of the role that dams play in our lives, or of the devastation that could come about from a dam failure. Even developers and officials are often in the dark about dams in their own communities. And, of course, everyone needs to understand that all high-hazard dams, no matter how seemingly structurally sound, are potentially dangerous and that there is inherent risk living in a dam break flood-prone area. Also, many of the private dam owners in our country are largely unaware of both their responsibility toward residents and businesses located downstream of their dam and of proper dam maintenance and repair procedures.

In Conclusion

We must change the way we manage our nation’s dams in order to prevent future catastrophes. The recent Oroville Dam crisis should serve as a warning to residents and legislators. As our dams age and climate change increases severe weather events, we must invest in the oversight, funding, and awareness of this critical infrastructure. Until we do, events such as the Oroville Dam crisis and the Ka Loko Dam failure may occur with increasing frequency, resulting in loss of life, environmental damage, and economic disaster.

The 7 Most Interesting Dams in the United States

Grand Coulee Dam
Grand Coulee Dam

1. Grand Coulee Dam

The Grand Coulee Dam, a concrete gravity dam, is located on the Columbia River west of Spokane, Washington and is listed by the American Society of Civil Engineers as one of the seven civil engineering wonders of the United States. The dam’s reservoir, Franklin D. Roosevelt Lake, stretches 150 miles north and almost reaches the Canadian border. The dam was constructed to provide hydroelectric power and irrigation.

Even more enormous than the Great Pyramid of Giza, the Grand Coulee is an absolutely massive structure, and one of the largest ever constructed by mankind. The 550 foot tall dam contains over 12 million cubic yards of concrete, which is enough to build a highway all the way from Miami, Florida to Seattle, Washington, and stretches 5,223 feet — just 57 feet shy of a mile. The construction of the Grand Coulee dam took place between 1933 and 1942 and provided jobs to thousands of men during the Great Depression. The Grand Coulee provided the immense electrical power needed to manufacture aluminum for the production of World War II planes and ships, and, continuing in its war-like vein, it also powered the production of plutonium at a secret lab on nearby Hanford Site. Plutonium, of course, turned out to be the key ingredient of the atomic bomb – and the rest is history.

The dam is not without some controversy. 77 men lost their lives during the construction of the dam and its original two powerhouses, and another four perished during the construction of the third power plant constructed between 1967-1975, bringing the final death count to 81. Also, creation of the reservoir partially flooded the ancestral lands of Native Americans and forced the relocation of over 3,000 people, and environmentalists have condemned the dam for blocking the migration of salmon and steelhead to spawn.

Today, the Grand Coulee is used to irrigate about 670,000 acres of farmland used for growing grains, fruits, vegetables, and wine grapes, as well as livestock grazing.

Hoover Dam
Hoover Dam

2. Hoover Dam

The Hoover Dam, located in the Black Canyon of the Colorado River on the border of Arizona and Nevada, is a massive concrete arch-gravity dam whose 600-foot base is as wide as the full length of two football fields. The giant concrete wedge stands 726 feet tall, or the height of a 60-story building, and holds back the immense power of the Colorado River. The Hoover Dam was constructed in order to generate electricity as well as provide irrigation and control flooding, and today generates about four billion kilowatts of electricity per year – enough to provide the power needs for 1.3 million people.

At the time of its construction between 1931 and 1935, the Hoover Dam was the most expensive engineering project in United States history at a cost of $49 million, which, adjusting for inflation, would be $700 million by today’s standards. The Hoover Dam created the enormous reservoir known as Lake Mead, which even today is the largest manmade reservoir in the U.S. at 110 miles long and 560 feet deep. In addition, the Hoover Dam and beautiful Lake Mead have created a bustling tourism community by providing plenty of outdoor recreation including boating, swimming, and fishing. Lake Mead also supplies municipal water for Las Vegas, Phoenix, and Tucson, and provides storage during drought.

Building the Hoover Dam took enormous effort. Construction of the dam utilized 91.8 billion cubic feet of concrete to create a retaining wall that weighs about 6.6 million tons. In fact, the mass of concrete in the Hoover Dam would pave a road from San Francisco to New York City. In addition, the volume of water in Lake Mead, when filled to capacity, is enough to submerge the entire state of Connecticut in ten feet of water. Incredibly enough, although the dam was expected to take five years to construct, it was actually completed ahead of schedule. 96 people died during the construction of the Hoover Dam; however, contrary to the popular urban legend, none of the deceased are encased within the dam’s concrete.

Oroville Dam
Oroville Dam

3. Oroville Dam

Oroville Dam, located about 70 miles north of Sacramento at the three forks of the Feather River, is the tallest dam in the United States, standing over 770 feet tall. The dam is an earthfill dam that holds back Lake Oroville, a manmade reservoir containing 3.5 million acre-feet of water. Oroville Dam stretches three quarters of a mile at its base and almost 7,000 feet across at its top.

The most highly monitored dam in the world during construction, the Oroville Dam was built between 1961 and 1967, and was officially dedicated in 1968. Just seven short years later, in 1975, a significant earthquake struck a few miles southeast of Oroville, and the new dam was put to the test. To the credit of the engineers, the dam oscillated with the earthquake and did not suffer a solitary crack or leak.

The Oroville Dam, along with its reservoir, Lake Oroville, not only provides drinking water, water storage, and hydroelectric power, it also protects downstream residents from the flooding of the Feather River. Providing about 750,000 acre-feet of flood control storage, the Oroville Dam has minimized damage from floods that have occurred in every decade since the dam’s construction. It also provides a beautiful location for a plethora of recreational activities including boating, camping, and fishing.

Tragically, 34 men died during the construction of the Oroville Dam. Just two years after the dam’s completion, President Richard Nixon signed the Occupational Safety and Health Act (OSHA) into law, drastically reducing the number of workplace accidents and casualties.

Redridge Steel Dam
Redridge Steel Dam

4. Redridge Steel Dam

Located across the Salmon Trout River in Redridge, Michigan, the Redridge Steel Dam is is a flat slab buttress dam constructed of steel. Steel is rarely used for construction of dams, which are typically earthenworks or masonry, and the Redridge Steel Dam is one of only three steel dams ever constructed in the United States. The other two are the Ashfork-Bainbridge Steel Dam, constructed in Arizona in 1898 to supply water for railway operations and still fully operational, and the Hauser Lake Dam, which was constructed in 1901 in Montana but failed less than a year later.

Timber Crib Dam Falls
Timber Crib Dam Falls

Prior to the construction of the Redridge Steel Dam, the Atlantic Mining Company built a timber crib dam across the Salmon Trout River in order to create a reservoir to supply water for mining operations. The reservoir created by the timber crib dam was insufficient, and so the Redridge Steel Dam was built; however, the original timber crib dam remained submerged in place upstream of the new dam. After operating for several decades, the Redridge Steel Dam fell into disrepair after mining operations ceased, and in 1941, the dam broke and caused a flood. The dam owners opened the spillways and cut holes in the steel dam so that it would no longer retain any water, and in this way the original timber dam was revealed — and along with it, breathtaking waterfalls.

With the threat of being labeled a “significant hazard” dam by the Michigan Department of Environmental looming, the timber dam was lowered 13 feet in 2004 in order to relieve pressure and make it safer. While a more permanent solution is still needed, both dams have been estimated to be safe for the foreseeable future, allowing visitors the ability to appreciate the lovely falls created by the old timber dam.

Roosevelt Dam
Roosevelt Dam

5. Roosevelt Dam

Constructed between the walls of a box canyon near the Salt River and Tonto Creek, the Roosevelt Dam was the first water project built under the 1902 Reclamation Act, and was the largest masonry dam in the world at that time. Italian stonecutters carved the stones used in the construction of the dam from the nearby cliffs, and when completed, the dam stood 280 feet tall and 184 feet wide at its base. The dam supplied water and electricity while also controlling the dangerous floods that had plagued the nearby Phoenix area.

Construction of the dam occurred between 1905 and 1911 while Arizona was still just a territory, and the total cost was $10 million. Supplying electricity to rural households, the Roosevelt Dam was a modern marvel. It would be ten years before the National Rural Electrification Act brought power to the rest of rural America, and so Phoenix quickly became a bright, modern city, and Arizona officially became a state only one year after the dam’s completion. The Roosevelt Dam was listed as a National Historic Landmark in 1963 and, to this day, it adorns the state seal of Arizona.

Dworshak Dam
Dworshak Dam

6. Dworshak Dam

Located just outside the city of Orofino, Idaho on the North Fork of the Clearwater River, the Dworshak Dam is the tallest straight axis gravity dam in the Western Hemisphere and the third highest dam in the United States. Constructed between 1966 and 1973, the Dworshak Dam is primarily used for flood control and hydroelectric power. The dam has three power-generating unts and received authorization for three more in 1990; however, the authorizations were revoked amid political controversy and citizen opposition when it was found that a second dam would be needed to handle peak loads.

The reservoir created by the Dworshak Dam holds almost 3.5 million acre-feet of water and is 53 miles long. The dam stands 717 feet tall, generates 380,000 kilowatts of power, and contains more than twice the concrete than does Cheope’s Great Pyramid in El Giza, Egypt.

Perhaps more notable than its significant mass is the controversy that has surrounded the Dworshak Dam since its inception. In his travel guide Idaho for the Curious, Cort Conley writes, “There have always been more politicians than suitable damsites. Building the highest straight axis gravity dam in the Western Hemisphere, on a river with a mean flow of 5,000 cubic feet per second, at a cost of $312 million, in the name of flood-control, is the second-funniest joke in Idaho. The funniest joke is inside the visitor center: a government sign entreats, ‘…help protect this delicate environment for future generations.’ The North Fork of the Clearwater was an exceptional river with a preeminent run of steelhead trout, and the drainage contained thousands of elk and white-tail deer. The Army Corps of Engineers proceeded to destroy the river, habitat, and fish; then acquired 5,000 acres for elk management and spent $21 million to build the largest steelhead hatchery in the world, maintaining at a cost of $1 million dollars a year what nature had provided for nothing.”

New Cornelia Mine Tailings Dam
New Cornelia Mine Tailings Dam

7. New Cornelia Mine Tailings

OK, so the New Cornelia Mine Tailings is not really a dam per se, but it IS often cited as the largest dam structure in the country by its volume of 7.4 billion cubic feet. Located just south of Ajo, Arizona, the New Cornelia Mine was operational from 1912 until 1983, when it closed due to the low price of copper. Mine tailings are waste materials such as bits of rock, dirt, mud, and process effluent from the mining process. While the mine was operational, the tailings were heaped into an enormous pile in order to hold back future tailings, and therefore the tailings pile is actually considered a dam. Today, Phelps Dodge owns the mine. There has also been recent talk of mining the tailings, although nothing has yet been scheduled.

Do you agree with our list of the 7 most interesting dams in the United States or do you know of a dam that should be included? Let us know – we’d love to hear from you!

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