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188,000 Flee as 'Wall of Water' Threatens Northern California

As nearly 200,000 Northern California residents flee to higher ground over the threat of the Oroville Dam emergency spillway's failure Sunday night, a report has emerged that state and federal officials were warned 12 years ago that the earthen structure was already at risk of erosion.

The Mercury News reported that back in Oct. 2005, Friends of the River, the Sierra Club and the South Yuba Citizens League filed a motion with the Federal Energy Regulatory Commission (FERC) during the Oroville Dam's relicensing process.

The environmental groups said that the dam, which California built and completed in 1968, did not meet modern safety standards and urged FERC to secure the dam's emergency spillway with concrete rather than have it remain as an earthen hillside.

Should extreme rain and flooding occur, the groups warned that the excess water could overwhelm the main concrete spillway and flow into the auxiliary spillway. Too much water could cause heavy erosion and potentially unleash flooding and threaten nearby communities.

"A loss of crest control could not only cause additional damage to project lands and facilities but also cause damages and threaten lives in the protected floodplain downstream," the groups wrote.

However, FERC rejected the groups' request. Furthermore, California's Department of Water Resources and other water agencies that would have paid for the upgrades said the fix was unnecessary.

"It is important to recognize that during a rare event with the emergency spillway flowing at its design capacity, spillway operations would not affect reservoir control or endanger the dam," wrote John Onderdonk, a FERC senior civil engineer in a July 27, 2006 memo to his managers.

"The emergency spillway meets FERC's engineering guidelines for an emergency spillway," he added. "The guidelines specify that during a rare flood event, it is acceptable for the emergency spillway to sustain significant damage."

KQED describes the emergency spillway as "essentially an ungated 1,700-foot-wide notch in the rim of the reservoir ... Below an initial concrete lip, water courses over bare earth all the way to the Feather River below, scouring the incline of earth, rocks and trees."

The secondary spillway has not been needed for use in its 48-year history—until this weekend.

The water level at Lake Oroville, California's second-largest reservoir, rose to record levels of more than a foot above what's considered "full" after Northern California's particularly wet winter. The lake also receives water from the northern Sierra Nevada mountain range, which also saw heavy rainfall, CNN noted.

Although the recent rainfall has brought much-needed relief to California's six years of epic drought, the nation's tallest dam is now nearly full. Water levels at the 770-foot-tall structure were less than seven feet from the top on Friday.

While the Oroville Dam is not currently compromised, both its primary spillway and the emergency spillway have problems due to severe erosion, authorities warned.

The primary spillway has a growing hole that is 250 feet long, 170 feet wide and about 40 to 50 feet deep, according to Bill Croyle, acting director of the Department of Water Resources. Because of the main spillway's damage, water has been pouring into the emergency spillway.

Fortunately, water has stopped pouring over the dam's emergency spillway since Sunday night.

"Oroville lake levels have receded to the point that auxiliary spillway flows have stopped. DWR hopes to push over a million acre feet of water over the main spillway in the next week, clearing the way for much needed flood storage in the lake," California's Department of Water Resources said.

Still, officials are planning for the worst as the situation could yet become dangerous.

"This is not a drill. Repeat this is not a drill," the National Weather Service said Sunday, urging people living near Oroville Dam to evacuate.

A collapse of the secondary spillway could cause a "30-foot wall of water" coming out of Lake Oroville, Cal-Fire incident commander Kevin Lawson said at a Sunday night press conference.

Evacuation orders are unchanged as of Monday morning.

"Once you have damage to a structure like that it's catastrophic," Croyle said. However, he stressed that "the integrity of the dam is not impacted" by the damaged spillway.

California Gov. Jerry Brown has issued an emergency order in response to the situation.

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Louisiana Faces Faster Levels of Sea-Level Rise Than Any Other Land on Earth

Louisiana—which faces faster levels of sea-level rise than any other land on Earth—could lose as many as 2,800 square miles of its coast over the next 40 years and about 27,000 buildings will need to be flood-proofed, elevated or bought out, the New Orleans Advocate reported.

These dire predictions were pulled from a new rewrite of the state's Coastal Master Plan for 2017 released Tuesday by the Louisiana Coastal Protection and Restoration Authority.

The plan, first introduced in 2007 post- Hurricane Katrina, acts as a 50-year blueprint for restoring the Pelican State's rapidly disappearing coastal wetlands and protecting the state's natural resources and communities. Louisiana's Legislature unanimously approved the 2007 and 2012 versions.

The new plan, which is now out for public review and must be voted up or down by the Legislature, calls for 120 new projects, including a $6 billion proposal to protect or vacate properties in areas that are at risk of experiencing a 100-year storm. The plan also aims to restore 800 to 1,200 square miles of wetlands and build new levees and flood walls to protect against hurricane storm surges.

The plan was authored by state coastal scientists and engineers and several federal agencies. Stakeholders from the shipping and fishing industries also provided input.

The most significant details are the grim edits made to the 2012 plan. As the Advocate detailed, "the worst-case scenario for human-caused sea-level rise in the 2012 plan, 1.48 feet, has become the best-case scenario in the 2017 edition. In fact, the National Climate Assessment now estimates sea levels on U.S. coastlines could rise 4 feet by 2100."

Not only that, "the new worst-case scenario projects that 4,000 square miles of the coast would be lost if the state stops all efforts to restore its coastal landscape. That's double the loss projected in the same scenario in the 2012 plan," the Advocate explained.

The plan's original investment was $50 billion, but an evaluation from Tulane University determined that its actual inflation-adjusted cost is now around $92 billion.

The report does not shy away from pointing fingers at natural disasters and human-caused climate change that have contributed to the state's alarming coastal erosion.

"Between 1932 and 2010, Louisiana's coast lost more than 1,800 square miles of land. From 2004 through 2008 alone, more than 300 square miles of marshland were lost to Hurricanes Katrina, Rita, Gustav, and Ike," the report states. "The culprits to this land loss include the effects of climate change, sea level rise, subsidence, hurricanes, storm surges, flooding, disconnecting the Mississippi River from coastal marshes, and human impacts."

Earlier reports have described how Louisiana's wetlands are disappearing at a rate of approximately one football field every hour and coastal communities are already washing into the Gulf of Mexico.

In June, reports emerged of the first American climate refugees. Residents from a Louisiana island called Isle de Jean Charles were forced off the land they have lived on for generations due to encroaching water. The island, which used to be the size of Manhattan, has lost 98 percent of its land over the last 60 years.

Additionally, NPR reported on Wednesday that it's not just land that's being swallowed up by the Gulf of Mexico, but also important ancient archaeological sites dating 300 to 500 years back.

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