The NID consists of dams meeting at least one of the following criteria: 1) High hazard potential classification – loss of human life is likely if the dam fails; 2) Significant hazard potential classification – no probable loss of human life but can cause economic loss; environmental damage, disruption of lifeline facilities, or impact other concerns; 3) Equal or exceed 25 feet in height and exceed 15 acre-feet in storage; 4) Equal or exceed 50 acre-feet storage and exceed 6 feet in height. (There are many more dams across the nation that are privately owned and not inspected.)
15,498Dams Identified as High-Hazard – Another 11,882dams are currently labeled significant hazard potential, meaning a failure would not necessarily cause a loss of life but could result in significant economic losses. While these figures climb, the increase has slowed because more dams are inspected on a more regular basis, allowing for the identification of deficiencies before they lead to a failure.
Don’t let them kid you, this DAM issue is not organic. They built the Dams and they are bringing them down. It is part of AGENDA 2030, and it is totally orchestrated. If you don’t know by now that they have the ability to control the weather… you have not been listening. They have been telling you outright themselves for years now, and they had the ability long before that. DO YOUR RESEARCH. Anyway, they are using weather control to bring down the DAMs because that is a lot easier and cheaper for them. It also causes less public outcry. I mean, how can you blame them if it is an act of GOD, right??
I could just kick my self because some years back I was researching the removal of Dams across America. At that time I found a map of all the Dams in the US, one of the Dams that had been removed and were scheduled to be removed, one of all the Nuclear Power Sites across the US, and one of the Fault Lines across the US. When I compared them my mind was blown. It was like they deliberately were trying to create disasters. If they were printed on clear plastic, you could lay them on top of each other and they would line up perfectly. For a long time I saved those maps and showed them to friends. When my old laptop crashed and burned, I lost them.
Now you cannot pull up any maps that will show you all the locations of the dams across the US. If you dig a lot, which I do, you can find some that come close. I have included some maps below as well as the one I have place at the top of this article.
How many U.S. dams are at risk of a crisis like the one currently unfolding in California, as officials work to stave off disaster at the compromised Oroville Dam? The short answer is, we don’t really know—but probably quite a few.
Until this month, Oroville’s emergency spillway had never been used in its nearly 50-year history. After weeks of rain and a breach in the dam’s main spillway, officials turned to the auxiliary one to help prevent an overflow from the dam’s lake. The resulting hillside erosion threatened serious flooding and prompted the evacuation of some 188,000 people.
Environmental groups predicted the crisis in 2005 when they called for the emergency spillway to be reinforced with concrete, but state officials dismissed that request as unnecessary. Though cost wasn’t publicly cited as a factor, critics can reasonably contend it was a consideration.
If so, “it’s certainly not the only dam that put off upgrades because of upfront cost,” says Jenny Rowland, public lands research and advocacy manager for the policy think tank Center for American Progress.
Oroville is just one of more than 90,000 dams across the country, many of which are aging and underfunded, prompting the American Society of Civil Engineers (ASCE) to give the nation’s dams a “D” grade in its last infrastructure report. In Minnesota, for example, repairs to the 107-year-old Byllesby Dam have been postponed for lack of funding.
Byllesby is one of more than 15,000 dams federally classified as “high hazard potential,” which says nothing about a dam’s actual condition, but indicates that a failure would result in “probable loss of life.” Missouri, North Carolina, and Texas have the highest concentrations of those dams, according to the infrastructure report—and there are at least a couple dozen in every state.
Heavy flows from the Oroville Dam spillway continue to push debris into the Feather River.
PHOTOGRAPH BY FLORENCE LOW, CALIFORNIA DEPARTMENT OF WATER RESOURCES
The number of high hazard potential dams is increasing because many of them were built in rural areas where the risks to nearby residents didn’t need to be considered at the time. But as the population increases, many dams are subject to what’s known as “hazard creep.”
“Rural and urban population sprawl has created new development downstream of many existing dams,” Rowland writes in a report on U.S. dams released last fall, “putting more people at risk should a dam fail.”
The U.S. has a National Inventory of Dams, but that doesn’t track thousands of smaller dams that could still cause damage, Rowland says, and it doesn’t tell you a dam’s condition. About 64 percent of them are privately owned, and another 20 percent are operated at the local or state level, like Oroville.
“There’s a lot of different ownership going on and not really a comprehensive reporting database,” Rowland says, adding that there is no systematic identification of which dams need upgrades or should be removed altogether. The latter are increasingly targeted by activists who say such “deadbeat dams” that no longer provide useful functions should be taken down, to reduce risk and restore habitat for wildlife.
Water flows through a gaping hole in Idaho’s Teton Dam, which failed in 1976, killing 11 people.
PHOTOGRAPH FROM BETTMAN, CORBIS
Still, states have stepped up their inspection efforts in recent years, according to the Association of State Dam Safety Officials (ASDSO). The average dam is more than 50 years old, and more than 4,000 of them have been deemed “deficient,” or needing repairs.
“At best, putting off repairs will likely cost the dam owner five to ten times as much, fifteen years down the road,” the organization says in a fact sheet. “At worst, it kills people.”
Eleven people died when Idaho’s Teton Dam failed in 1976. That and other catastrophic, deadly failures in the 1970s led to the creation of the National Dam Safety Program, which drove an increase in inspections and emergency plans.
Teton was a “milestone event” that led to a rethinking of dam safety, says John France, an expert with the ACSE. Now every state except Alabama has a safety program to handle inspections, training, and other precautions. France says the industry also has done a better job at factoring “everyday issues” such as erosion into safety risk, along with rarer events such as floods and earthquakes.
“Overall, dam safety in the country has improved in the last 30 years,” France says, “but we’ve got a lot more work to do.”
France notes that designers of older dams didn’t know as much as we do now about dams and how they perform when stressed, which can lead to design deficiencies. This, along with hazard creep and general wear and tear, means the number of dams susceptible to failure has more than quadrupled in the last 15 years, according to state safety officials.
But modernizing dams costs money, and funding hasn’t been sufficient. Some dams have seen critical repairs in recent years: Kentucky’s Wolf Creek and California’s Folsom are recent examples. Still, “for every high-hazard-potential dam repaired,” the ASDSO says, “nearly two more dams have been declared deficient.”
Rowland at the Center for American Progress argues for a federal fund to help subsidize upgrades and repairs at sites like Oroville—the kind of projects that wouldn’t necessarily attract the investors on which President Donald Trump’s infrastructure plan relies. Certainly, addressing all of the potential failure points in the current U.S. dam system will require a flood of cash: The ASDSO puts the figure at “well over $60 billion.”
The purpose of this section is to provide a summary of basic information related to the inventory of dams within the United States. This data is helpful for establishing new guidelines for the hydrologic safety of existing and new dams as it provides general information on the location, age, ownership, hazard classification and size of dams in the United States. This summary of dams is based on information cataloged and reported by the Association of State Dam Safety Officials (ASDSO), the US Army Corps of Engineers (USACE), the American Society of Civil Engineers (ASCE) and the Federal Emergency Management Agency (FEMA) as described in the following paragraphs. Data from each of these entities does vary; therefore, there are inconsistencies in the data presented from various sources in this chapter.
National Inventory of Dams
The National Inventory of Dams (NID) is a database of dams in the United States which was developed and is maintained by the USACE. Congress authorized the USACE to inventory dams as part of the 1972 National Dam Inspection Act. Several subsequent acts have authorized maintenance of the NID and provided funding. The USACE collaborates with FEMA and state regulatory offices to collect data on dams. The goal of the NID is to include all dams in the United States which meet at least one of the following criteria: 1. High hazard classification – loss of at least one human life is likely if the dam fails 2. Significant hazard classification – possible loss of human life and likely significant property or environmental destruction 3. Equal or exceed 25 feet in height and exceed 15 acre-feet in storage 4. Equal or exceed 50 acre-feet storage and exceed 6 feet in height Low hazard dams which do not meet the criteria specified in number 3 or 4 are not included in the NID even if they are regulated according to state criteria. In some states, the number of these dams is several times the number of dams included in the NID.
Association of State Dam Safety Officials
In addition to using information collected as part of the NID, ASDSO annually collects additional information on dams in the United States by survey for their State Dam Safety Program Performance Information Report. ASDSO data focuses on dams within the jurisdiction of each state regardless of whether or not they are included in the NID.
American Society of Civil Engineers
Since 1998, ASCE has issued four reports titled “Report Card for America’s Infrastructure.” These reports depict the condition and performance of the nation’s infrastructure, including dams, and were prepared by an advisory panel of the nation’s leading civil engineers. This panel analyzed hundreds of reports and studies in the process of assigning grades as well as surveying thousands of engineers.
Federal Emergency Management Agency
As part of the U.S. Department of Homeland Security, FEMA also has an interest in dam safety in the United States. In their 2010 biennial report to Congress, “Dam Safety in the United States, A Progress Report on the National Dam Safety Program,” FEMA describes the achievements of the states, the federal agencies, and their partners in Fiscal Year (FY) 2008 and FY 2009 in meeting the vision, mission, and objectives of the National Dam Safety Program. This document contains many interesting statistics and graphics that are useful in summarizing the dam inventory of the United States.
2.2. Summary of Significant Statistics for Dams in the United States
Dam construction in the United States began in earnest in the second half of the 19th century and peaked with the surge in the American economy and population following World War II. The current NID contains data on nearly 84,000 dams. The average age of these dams is over 50 years. Figure 2.1 shows the relative construction date of dams based on data in the NID. The 2009 Report Card for America’s Infrastructure on Dams, prepared by ASCE, indicates that age has a two-fold effect on the determination of deficiency of a dam. First, the age of a dam contributes to deterioration. Second, design criteria and loadings which were considered appropriate at the time of design, may now be considered insufficient, leading to dams being considered unsafe or deficient. The same publication reports that the number of dams determined to be unsafe or deficient is rising and now stands at more than 4,400 dams. ASCE’s 2009 Report Card states, “Over the past six years, for every deficient, high hazard potential dam repaired, nearly two more were declared deficient.” Not only are dams in the United States aging and being declared deficient, but, at the same time, the number of high hazard potential dams is also increasing at a significant rate. According to statistics maintained by ASDSO, for the 10-year period from 2000 through 2009, the number of dams listed in the NID increased by about 9 percent. During this same period, the number of high-hazard, state-regulated dams increased by almost 14 percent. ASCE’s 2009 Report Card on Dams states that the trend of increasing number of high hazard dams is a result of higher consequences of failure spurred by new downstream development. Development both upstream and downstream of dams is a widespread concern. Within the United States, dams are owned and regulated by a variety of organizations. Most dams are privately or municipally-owned and are state-regulated. Figure 2.2 is a map of the United States showing the distribution of low, significant and high hazard potential dams. Figure 2.3 is a similar map showing only state-regulated high hazard potential dams.
Figure map showing only state-regulated high hazard potential dams.
According to the FEMA biennial report to Congress, the federal government owns or regulates approximately 6 percent of the dams in the United States, and many of these dams are considerable in terms of size, function and hazard potential. The rest of the dams are within the jurisdiction of state dam safety programs. A summary of dams by state and hazard classification are summarized in Table 2-1 and Table 2-2. Figure 2.4 is a map showing the location of dams reported to the NID by the federal agencies. Table 2-3 is a summary of federal dam ownership by hazard classification. Table 2-1 Dam Safety Statistics from the NID [USACE, 2009; ASDSO, 2008] Hazard Potential State Regulated Dams Listed in the NID Total State Regulated Dams High 10,856 10,993 Significant 11,163 10,931 Low 45,142 66,112 Total 67,161 88,036
Table 2-2 State Dam Safety Program Statistics [ASDSO, 2008]
Table 2-3 Dams Owned and/or Regulated by Federal Agencies1 [FEMA, 2010]
