Réservoir n° 1, un approvisionnement en eau de 180 millions de gallons qui a été hors service une grande partie des dernières décennies, se trouve dans le contexte de l'horizon de la ville, 15 octobre 2019, à Atlanta. La ville a effectué des réparations et l'a remis en service en 2017, seulement pour le fermer à nouveau après que des fuites d'eau ont été remarquées près des entreprises situées sous le barrage. Si le barrage tombait en panne de manière catastrophique, l'eau pourrait inonder plus de 1, 000 maisons unifamiliales, des dizaines d'entreprises, un chemin de fer et une partie de l'Interstate 75, selon un plan d'action d'urgence. (Photo AP/David Goldman)
Par une froide matinée de mars dernier, Kenny Angel a reçu un coup frénétique à sa porte. Deux travailleurs d'une entreprise de services publics du nord du Nebraska étaient venus avec un avertissement sévère :Sortez de chez vous.
Un peu plus d'un quart de mille en amont, le barrage Spencer, âgé de 92 ans, s'efforçait de contenir le gonflement, rivière Niobrara recouverte de glace après une tempête de neige et de pluie exceptionnellement intense. Les ouvriers avaient essayé, sans succès, de forcer l'ouverture des vannes du déversoir en bois gelé du barrage. Donc, craindre le pire, ils se sont enfuis dans leur camion, s'arrêtant pour avertir Angel avant de partir sans lui.
Minutes plus tard, le barrage s'est effondré, déclenchant une vague d'eau transportant des morceaux de glace de la taille de voitures. La maison d'Angel a été balayée; Son corps n'a jamais été retrouvé.
"Il avait un préavis d'environ 5 minutes, sans préavis la veille, " Ange Scott, l'un des frères de Kenny, mentionné.
Les inspecteurs de l'État avaient attribué au barrage une note « correcte » moins d'un an plus tôt. Jusqu'à ce qu'il échoue, il avait l'air peu différent de milliers d'autres à travers les États-Unis - et cela pourrait laisser présager un problème.
Une enquête de plus de deux ans menée par l'Associated Press a trouvé des dizaines de barrages à l'échelle nationale dans un état encore pire, et dans des endroits tout aussi dangereux. Ils dominent les maisons, entreprises, des autoroutes ou des communautés entières qui pourraient faire face à des inondations potentiellement mortelles si les barrages ne tiennent pas.
Cette combinaison de photos fournies par le ministère des Ressources naturelles du Nebraska, montre le barrage Spencer près de Spencer, Bec., en novembre 2013, Haut, quand il retenait l'eau sur la rivière Niobrara et à nouveau en mars 2019, après la rupture du barrage lors d'une inondation. Les inspecteurs de l'État avaient attribué au barrage une note « correcte » moins d'un an plus tôt. Jusqu'à ce qu'il échoue, il avait l'air peu différent de milliers d'autres à travers les États-Unis, et cela pourrait laisser présager un problème. (Département des ressources naturelles du Nebraska via AP)
Un examen des données fédérales et des rapports obtenus en vertu des lois des États sur les dossiers ouverts a identifié 1, 688 barrages à haut risque classés dans un état médiocre ou insatisfaisant l'année dernière dans 44 États et à Porto Rico. Le nombre réel est presque certainement plus élevé :certains États ont refusé de fournir des évaluations de l'état de leurs barrages, réclamer des exemptions aux demandes d'enregistrement public. D'autres n'ont tout simplement pas évalué tous leurs barrages par manque de financement, le personnel ou l'autorité pour le faire.
Les décès dus aux ruptures de barrages ont diminué depuis qu'une série d'effondrements catastrophiques dans les années 1970 a incité les gouvernements fédéral et étatiques à intensifier leurs efforts de sécurité. Pourtant, environ 1, 000 barrages ont échoué au cours des quatre dernières décennies, tuant 34 personnes, selon le programme national de performance des barrages de l'université de Stanford.
Conçu pour le contrôle des inondations, irrigation, approvisionnement en eau, l'hydroélectricité, stockage de déchets récréatifs ou industriels, les barrages du pays ont en moyenne plus d'un demi-siècle. Certains ne sont plus adaptés pour faire face aux pluies intenses et aux inondations d'un climat changeant. Pourtant, on compte sur eux pour protéger de plus en plus de personnes à mesure que des développements immobiliers se développent à proximité.
"Il y a des milliers de personnes dans ce pays qui vivent en aval de barrages qui sont probablement considérés comme déficients compte tenu des normes de sécurité actuelles, " a déclaré Mark Ogden, un ancien responsable de la sécurité des barrages de l'Ohio qui est maintenant un spécialiste technique de l'Association of State Dam Safety Officials.
L'association estime qu'il faudrait plus de 70 milliards de dollars pour réparer et moderniser les plus de 90, 000 barrages. Mais contrairement à beaucoup d'autres infrastructures, la plupart des barrages américains sont privés. Cela rend difficile pour les régulateurs d'exiger des améliorations de la part des opérateurs qui ne sont pas en mesure ou ne veulent pas payer les coûts élevés.
"La plupart des gens n'ont aucune idée des vulnérabilités lorsqu'ils vivent en aval de ces barrages privés, " a déclaré Craig Fugate, un ancien administrateur de l'Agence fédérale de gestion des urgences. "Quand ils échouent, ils n'échouent pas avec avertissement. Ils échouent tout simplement, et soudain, vous pouvez vous retrouver dans une situation où vous avez un mur d'eau et de débris qui se précipitent vers votre maison en très peu de temps, si seulement, sortir."
Joël Iverson, chef de l'exploitation de Monday Night Brewing, est photographié dans la brasserie qui se trouve à côté du réservoir n° 1, un approvisionnement en eau de 180 millions de gallons qui a été hors service une grande partie des dernières décennies, 15 octobre 2019, à Atlanta. Iverson a déjà remarqué que de l'eau s'écoulait de la colline du barrage près de la brasserie qu'il a cofondée. "Si celui-là s'en va, ça va nous emporter et beaucoup de bière, " a déclaré Iverson. (AP Photo/David Goldman)
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On ne sait pas si Angel, un vétéran de la guerre du Vietnam de 71 ans, a refusé de fuir ou a simplement manqué de temps après que des travailleurs du Nebraska Public Power District l'ont averti que l'eau débordait du barrage près de Spencer, une ville de moins de 500 habitants.
Un avocat pour la femme d'Angel, qui n'était pas à la maison quand le barrage s'est rompu, a déposé une plainte de 5 millions de dollars pour négligence. Il prétend que le service public d'électricité n'a pas correctement entretenu le barrage, former ses employés ou informer les Anges des conditions dangereuses.
Même si la maison des Anges était carrément sur son chemin, le barrage a été classé comme un risque « important » plutôt que « élevé », ce qui signifie qu'il n'était pas nécessaire en vertu de la loi du Nebraska d'avoir un plan d'action d'urgence formel. Environ 20% des barrages à haut risque réglementés par l'État à l'échelle nationale n'ont toujours pas de plans d'urgence, selon l'US Army Corps of Engineers, qui maintient l'inventaire national des barrages.
Lors de la dernière inspection en avril 2018, La note « passable » de Spencer Dam était accompagnée d'une notation inquiétante :« Des déficiences existent qui pourraient conduire à une défaillance du barrage pendant tempêtes extrêmes."
Tim Gokie, ingénieur en chef du programme de sécurité des barrages du Nebraska, a déclaré que l'avertissement était dû à des infiltrations d'eau passées que le service public d'électricité a résolues en installant un système de drainage. Finalement, Gokie a dit, la crue du fleuve Niobrara a simplement submergé le barrage en béton et en terre, qui a été construit en 1927 pour produire de l'hydroélectricité, pas pour le contrôle des inondations.
En ce 27 décembre, 2018, photo, Plage de Murray, un banquier d'investissement qui vit sur la rive de Willett Pond, rappelle le déversoir du lac, qui est situé à la frontière de Norwood et Walpole, Mass. Le déversoir du barrage Willett Pond, vieux de 107 ans, n'est capable de traiter que 13 % du débit d'eau d'une grave inondation avant que le barrage ne soit dépassé, selon un récent rapport d'inspection de l'État. "Nous ne parlons pas seulement d'inonder la maison de quelqu'un. Nous parlons de couvrir sa maison, " dit la plage, qui appartient à un groupe de citoyens qui fait pression depuis des années pour que l'évacuateur de crues soit réparé. (Photo AP/Charles Krupa)
"Le fait est que c'était juste une situation sans précédent, " Le porte-parole du Nebraska Public Power District, Mark Becker, a déclaré. "C'était au-delà de ce que tout le monde avait prévu."
Le Nebraska a été parmi les États les plus durement touchés par les tempêtes et les inondations cette année, qui ont causé des dommages estimés à 1,5 milliard de dollars aux routes, barrages, services publics et autres infrastructures dans 28 États, selon une analyse AP.
Une évaluation nationale du climat publiée par la Maison Blanche l'année dernière a noté une fréquence et une intensité croissantes des tempêtes à mesure que le climat change. Cela peut pousser certains barrages au-delà de ce pour quoi ils ont été conçus.
Même conservé en bon état, des milliers de barrages pourraient être menacés en raison d'orages violents, dit Fugate, the former FEMA official.
"These are like ticking bombs just sitting there, waiting for the wrong conditions to occur to cause catastrophic failure, " il a dit.
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A vehicle passes over the spillway at Willett Pond on the border of Norwood and Walpole, Mass., Dec. 27, 2018. If the dam were to give way, it could send hundreds of millions of gallons of water into the heart of the Norwood, a Boston suburb of nearly 30, 000 personnes. (AP Photo/Charles Krupa)
The nation's dams are categorized as high, significant or low hazard in the National Inventory of Dams database. High hazard means loss of human life is likely if a dam were to fail. A significant rating means no deaths are likely, although economic and environmental damage are possible.
There is no national standard for inspecting dams, leading to a patchwork of state regulations. Some states inspect high-hazard dams every year while others wait up to five years. Some states never inspect low-hazard dams—though even farm ponds can eventually pose a high hazard as housing developments encroach.
Dam conditions are supposed to be rated as unsatisfactory, poor, fair or satisfactory. But the ratings are subjective—varying by state and the interpretations of individual inspectors—and are not always publicly disclosed.
Since the Sept. 11, 2001, terror attacks, the U.S. government has cited national security grounds in refusing to include dams' conditions in its inventory, which was updated most recently in 2018. But the AP was able to determine both condition and hazard ratings for more than 25, 000 dams across the country through public records requests.
The tally includes some of the nation's most well-known dams, such as Hoover Dam along the Colorado River, but mostly involves privately owned dams. Many are used for recreation.
The AP then examined inspection reports for hundreds of high-hazard dams in poor or unsatisfactory condition. Those reports cited a variety of problems:leaks that can indicate a dam is failing internally; unrepaired erosion from past instances of overtopping; holes from burrowing animals; tree growth that can destabilize earthen dams; and spillways too small to handle a large flood. Some dams were so overgrown with vegetation that they couldn't be fully inspected.
A surveyor walks the banks of the Mill River, at the site of the former Whittenton Pond Dam, just upstream from downtown Taunton, Mass., July 25, 2018. The dam was removed following concerns that the 170-year-old plus structure could fail, after it buckled and nearly failed in 2005. (AP Photo/Charles Krupa)
Georgia led the nation with nearly 200 high-hazard dams in unsatisfactory or poor condition, according to the AP's analysis.
Among them is Reservoir No. 1 in Atlanta, a 180 million-gallon water supply dating to the late 1800s that has been out of service much of the past few decades. The city made repairs and brought it back online in 2017, only to shut it down again after leaks were noticed.
If the dam were to catastrophically fail, the water could inundate more than 1, 000 foyers, dozens of businesses, a railroad and a portion of Interstate 75, according to an emergency action plan .
Joel Iverson has previously noticed water trickling out of the dam near the brewery he co-founded, Monday Night Brewing.
"If that one goes, it's going to wash away us and a lot of beer, " Iverson said.
The Atlanta Watershed Management Department declined the AP's request for an interview about the reservoir and instead asked for questions in writing. When those were submitted, it declined to answer them.
In this April 2, 2019, fichier photo, water flows down the Oroville Dam spillway in Oroville, Calif. The state spent $1.1 billion repairing the Lake Oroville spillway, enacted new emergency plan requirements and launched a review of 93 other dams with similar spillways. (AP Photo/Rich Pedroncelli, Déposer)
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One of the most common problems for aging dams are spillways incapable of handling an extreme rainfall event.
If water can't escape quickly enough through spillways, it could flow over the top of a dam, which increases the probability of rapid erosion that can cause it to collapse.
The spillway at the 107-year-old Willett Pond Dam near the Boston suburb of Norwood is capable of handling just 13% of the water flow from a serious flood before the dam is overtopped, according to a recent state inspection report. If the dam were to give way, it could send hundreds of millions of gallons of water into the heart of the city of nearly 30, 000 personnes.
"We are not talking of just flooding someone's house. We are talking about covering their house, " said Murray Beach, who lives on the shore of the 220-acre privately owned lake and belongs to a citizens group that has lobbied for years for the spillway to be repaired.
A 2017 inspection report said improvements to the spillway could cost between $1 million and $5 million. A nonprofit that owns the lake received a $215, 000 state grant last year to design spillway improvements. But there is no timeline to fix it.
In this Nov. 30, 2017, fichier photo, work continues on the Oroville Dam spillway in Oroville, Calif. The scare at Oroville, the nation's tallest dam, led to evacuation orders for nearly 200, 000 people, although no one was injured and the dam ultimately held. (AP Photo/Rich Pedroncelli, Déposer) 
Tamiko Porter, who operates a Montessori school serving some 75 students, said she was surprised to learn there was a dam upstream that could flood her school if it failed.
"Oh God, please let it happen when my kids aren't here, " Porter said.
Norwood emergency management director Bernard Cooper said there is no imminent risk of dam failure.
"Oui, it needs work. The spillway should be rebuilt. Absolument, no question, " Cooper acknowledged. But "there is no money in the system for that."
Concerns about inadequate dam spillways date back decades to when the Corps of Engineers undertook its first nationwide assessment of dams posing a high risk to life and property. From 1978 to 1981, the Corps inspected 8, 818 dams. About one-third were deemed unsafe due to deficiencies, and about 80% of those cited inadequate spillway capacities.
Hunter Croan walks along a dried-up section of Lake Dunlap, 30 septembre 2019, in Lake Dunlap, Texas. Croan is one of many homeowners who were left high and dry, their lakeside docks now dry as the Guadalupe River retreated to its natural bed after the the center spill gate of the lake's 91-year-old dam failed. (AP Photo/Eric Gay)
One of the dams cited for a "seriously inadequate" spillway in 1978 was Lake Sebago, located in a New York state park near the village of Sloatsburg. Forty years later, rien n'a changé.
A 2018 state inspection letter warned of "inadequate spillway capacity and dam stability" and asked for an improvement plan within 30 days. None was provided.
The state dam safety office has no authority to force the state parks department to make repairs.
To modify the Lake Sebago spillway, workers would have to rebuild a road and bridge that pass over the dam. The project could cost over $15 million, said Jim Hall, the recently retired executive director of the Palisades Interstate Park Commission, which manages multiple dams.
"That structure has been in place with the same spillway capacity for over probably 60 to 70 years and it hasn't been overtopped, " Hall said. "Should it be improved to meet all codes? Oui, that would be nice. Does it make it the highest priority for us to do in relation to other dam structures we have? Probably not."
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Water flows over a spill gate on Lake McQueeney, 2 octobre 2019, Lake McQueeney, Texas. A judge has issued a 12-month temporary injunction preventing the draining of McQueeney and five other lakes along the Guadalupe River after property owners sued. (AP Photo/Eric Gay)
In a 1982 report summarizing its nationwide dam assessment, the Corps of Engineers said most dam owners were unwilling to modify, repair or maintain the structures, and most states were unwilling to spend enough money for an effective dam safety program.
Depuis, every state but Alabama has created a dam safety program.
But the Great Recession a decade ago forced many states to make widespread budget and personnel cuts. Since a low point in 2011, states' total spending on dam safety has grown by about one-third to nearly $59 million in the 2019 fiscal year while staffing levels have risen by about one-fifth, according to data collected by the Corps of Engineers.
Californie, which runs the nation's largest dam safety program, accounts for much of that gain. It boosted its budget from $13 million to $20 million and the number of full-time staff from 63 to 77 following the failure of the Oroville dam spillway in 2017.
The scare at Oroville, the nation's tallest dam, led to evacuation orders for nearly 200, 000 people, although no one was injured and the dam ultimately held. An independent investigation cited "a long-term systemic failure " by regulators and the dam industry to recognize and address warning signs.
California spent $1.1 billion repairing the Lake Oroville spillway, enacted new emergency plan requirements and launched a review of 93 other dams with similar spillways.
Water spurts through a wood section of a spill gate on Lake McQueeney, 2 octobre 2019, Lake McQueeney, Texas. A judge has issued a temporary injunction preventing the draining of the lakes along the Guadalupe River as a result of an agreement between suing property owners and the Guadalupe-Blanco River Authority. (AP Photo/Eric Gay)
In South Carolina, after more than 70 dams failed following heavy rains in 2015 and 2016, the state tripled the personnel in its dam safety program and ratcheted up spending from about $260, 000 annually to more than $1 million.
But some states have continued to pare back their dam safety programs. Thirteen states and Puerto Rico were spending less in 2019 than they did in 2011, and 11 states had fewer full-time positions in their programs.
The Association of State Dam Safety Officials says almost every state faces a serious need to pump additional money and manpower into dam safety programs.
"If you don't have the staff to inspect a dam, or don't have the authority to do that, you don't know what the problems are, " said the association's Ogden.
"If you are able to do the inspection but you can't follow up, and you have dam owners who don't have the resources to fix their dam, then ultimately you know what the problem is but you can't get it addressed, " il ajouta.
Many states face a quandary when it comes to problematic private dams when they can't identify the owners. Rhode Island's two-person dam safety office last year listed 32 high- or significant-hazard dams with safety concerns whose owners were unknown.
Guadalupe-Blanco River Authority's John Moryl walks through the hydroelectric plant at the spill gates on Lake McQueeney, 2 octobre 2019, in Lake McQueeney, Texas. The Guadalupe-Blanco River Authority announced plans to drain a chain of six lakes, including Lake McQueeney. (AP Photo/Eric Gay)
"If we don't know the owner, then we can't take any action to order anybody to fix it, " said David Chopy, chief of compliance and inspection for the Rhode Island Department of Environmental Management.
Dans certains États, dams go uninspected because of exemptions in state law.
A 2013 Texas law exempts all dams on private property with a capacity of less than 163 million gallons that are rated significant or low hazard and are located outside of city limits in any county with fewer than 350, 000 personnes. Par conséquent, about 45% of its roughly 7, 200 dams are exempt from regulation.
Missouri performs safety inspections on only about 650 of its more than 5, 000 dams. That's because state law exempts all dams that are under 35 feet, used for agricultural purposes or subject to federal regulation.
Former Missouri Gov. Matt Blunt attempted to significantly expand the number of dams under state supervision after the mountaintop Taum Sauk Reservoir collapsed in December 2005, injuring a state park superintendent's family. But the legislation failed after some rural landowners expressed concerns. Then the proposal quietly faded away as new officials took over.
"Maybe it's time to take a look at that again and make sure that our dams are safe, " said Missouri state Rep. Tim Remole, who now leads the House committee overseeing dam safety.
This March 14, 2006, fichier photo, shows damage after a dam burst near Kilauea, on the Hawaiian island of Kauai. An earthen wall of the Kaloko Reservoir collapsed during heavy rains and sent a wave of water and mud rushing down a hillside. Seven people were killed on Bruce Fehring's property, including his daughter, son-in-law and grandson. (AP Photo/Casey Riemer, Déposer)
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Until Angel's death in Nebraska this year, the last fatal dam failure in the U.S. occurred on the Hawaiian island of Kauai in 2006.
An earthen wall of the Kaloko Reservoir collapsed during heavy rains and sent a wave of water rushing down a hillside. Seven people—including a pregnant woman—were killed on Bruce Fehring's property, including his daughter, son-in-law and grandson.
Fehring, who wasn't there at the time, got a phone call from a neighbor saying something terrible had happened. He was shocked by the scene.
"It took a while to register, and I went, 'Oh my God, everything's been washed away, '" Fehring recalled. "I mean, you have no idea the power of water (until) you see what it can do in a very short amount of time."
Dam owner James Pflueger pleaded no contest to felony reckless endangerment and was sentenced to seven months of confinement and five years of probation. His property company pleaded no contest to seven counts of manslaughter. Prosecutors said Pflueger had filled in the dam's spillway while attempting to make space for a waterfront development.
In this May 21, 2006, fichier photo, Bruce Fehring and his wife Cyndee, centre, lead a procession toward Kahili Quarry Beach during a memorial service to honor those killed when the Kaloko Dam failed in Kilauea, on the Hawaiian island of Kauai. An earthen wall of the Kaloko Reservoir collapsed during heavy rains and sent a wave of water and mud rushing down a hillside. Seven people were killed on Fehring's property, including his daughter, son-in-law and grandson. (Jamm Aquino/Honolulu Star-Bulletin via AP, Déposer)
Tess Coody-Anders, a university executive and homeowner near Lake McQueeney, one of the dams slated to be drained, stands near a sign showing the lake is closed, 30 septembre 2019, in Lake McQueeney, Texas. "This is something that communities and states all across the country are grappling with as we are reckoning with our aging infrastructure, " said Coody-Anders. (AP Photo/Eric Gay)
The victims' families and those whose property was damaged, including actress Bette Midler, agreed to a $25 million civil settlement. Though categorized by the state as low hazard at the time it failed, Kaloko Reservoir is now listed as a high-hazard facility in poor condition . It remains largely unrepaired.
That's also the case with Lake Dunlap Dam, northeast of San Antonio. On a sunny morning in May, one of the 91-year-old dam's corroded spillway gates suddenly gave way. No one was hurt in the rush of water, but scores of homeowners' lakeside docks were left high and dry, facing barren swaths of dried lakebed after the river retreated, leaving boats stranded.
The dam was the second hydroelectric facility along the river to fail within the past three years. The Guadalupe-Blanco River Authority responded with plans to drain a chain of four lakes because of concerns their similarly designed spillway gates also could fail.
But after property owners sued, the river authority agreed in September to a temporary injunction delaying the plan for a year. That could allow time to find funding for the estimated $90 million to $210 million to repair the dams.
Guadalupe-Blanco River Authority's John Moryl looks over the spill gates at Lake Dunlap, 2 octobre 2019, in Lake Dunlap, Texas. One of the spill gates at the dam failed in May and the lake drained down to the original channel of the Guadalupe River. (AP Photo/Eric Gay)
"This is something that communities and states all across the country are grappling with as we are reckoning with our aging infrastructure, " said Tess Coody-Anders, a homeowner near Lake McQueeney, one of the dams slated to be drained.
"I hope that everyone will recognize that, like in our community, entire economies and ways of life have developed around what started out as a civil engineering project, " she added. "And you can't take that away."
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