Amid the steady din of sea lion barks, bird chirps and crashing surf, a host of federal, state and tribal officials gathered around a fish cleaning table at the mouth of the Klamath River last week to sign a new agreement to remove the four dams that have clogged the river for decades and to chart a new path forward for communities from the Klamath's mouth to its headwaters.

Moments earlier, North Coast Congressman Jared Huffman pulled Yurok Tribal Chair Thomas O'Rourke aside. "Gosh, this is a great day," the congressman said. O'Rourke, clad in his trademark wide-brimmed hat, responded in his customary slow drawl. "My people," he said, "don't make that judgment until the sun sets."

It was a symbolic moment on a symbolic day. O'Rourke had been at a similar event six years earlier in Salem, Oregon, and inked his name to a similar agreement that pledged to take down the dams. He'd been there as then-California Gov. Arnold Schwarzenegger told the gathered crowd: "By finalizing that agreement we can say, 'hasta la vista' to the dams. I can already hear the salmon fish screaming, 'I'll be back.'" And O'Rourke had stood by and watched as that agreement shriveled on the vine and expired late last year when Congress failed to pass the legislation needed to enact it.

The history of the original Klamath agreements — a trio of hard-fought compromises crafted through a decade of negotiations between Klamath basin stakeholders — was not lost on those who addressed the crowd last week. Nor was the fact that the stakeholders who crafted those original agreements had resisted the desire to retreat into their corners and retrench in their philosophical divides, but had instead returned to the negotiating table. Also not lost was the fact that many of those stakeholders, including some who addressed that crowd on the bank of the Klamath River last week, were supporting the new deal with trepidation, fearful of what it means for their own futures but respectful of what it means to their counterparts.

"This is the absolute essence of non-extremism and non-polarization," Gov. Jerry Brown said. "It's called working together the way American government should."

What held the original Klamath agreements together was the fact that each of those who negotiated them left something behind. For ranchers and farmers along the upper Klamath, that meant agreeing to dam removal and shrinking the footprints of their farms and ranches in exchange for some water security in dry years. For lower Klamath tribes and environmental groups, that meant agreeing to see some water diverted to irrigators and farmers in exchange for dam removal and habitat restoration. For the Klamath Tribes of Oregon, that meant sending some of their water to farms and cattle ranches in exchange for dam removal and additional lands for their reservations.

But the pacts signed last week — the revised Klamath Hydroelectric Settlement Agreement and the Klamath Power and Facilities Agreement — contain only a fraction of those promises. They provide for the long-sought removal of the four dams that will open hundreds of miles of salmon spawning habitat, but only promise irrigators and farmers that stakeholders will continue to work to honor the initial agreements. The pacts also include a provision that irrigators and farmers will be protected from potential regulatory and legal threats associated with reintroducing — through the dam removals — salmon and other species that for decades have been absent in the upper river.

But those promises were enough to draw support, and to bring some farmers and irrigators down to the Klamath's mouth last week. "Our future will be determined by what happens next," said Scott White, executive director of the Klamath Water Users Association, which represents irrigators in the upper Klamath. "It would have been very easy to make this all about dams, but none of you did that."

U.S. Department of the Interior Secretary Sally Jewell said that's really the heart of what might become the largest river restoration project in the history of the United States — recognizing and respecting the people and communities that depend on the river, from its headwaters to its mouth. She pledged, "on the record and for the record," to honor those initial agreements and create a plan that works for irrigators, ranchers, tribes and fish.

A palpable excitement surrounded last week's signing ceremony. It resurrected a deal many thought dead just months before. And, without being hitched to a water deal, the new pact has even brought in some critics of its original counterpart, such the Hoopa Valley Tribe and some environmentalists who felt the old deal sacrificed too much. But — despite news headlines and speakers' excited claims that the dams are coming down — a lot remains to see this enormous undertaking to fruition. Or, as O'Rourke might say, there's a lot of daylight left before the sun sets on those Klamath's dams.

In a phone interview a couple of days after the new KHSA was signed, Craig Tucker sounded chipper. But having been involved in the dam removal effort since its inception, Tucker, now the Karuk Tribe's natural resources policy advocate, also knows enough to be cautious.

"It's not a 100 percent guaranteed thing," Tucker said, before explaining his optimism about the KHSA's new path. The new deal, Tucker said, does not require new legislation from Congress, which has a powerful conservative block of members who are ideologically opposed to dam removal.

Instead, the revised KHSA relies on the Federal Energy Regulation Commission, which Congress has already entrusted with the oversight of dam licensing and decommissioning. Under the settlement, the tribes, the states of Oregon and California, the federal government and the dams' owner — the Berkshire Hathaway subsidiary PacifiCorp — will submit a joint proposal to FERC. The FERC filing will ask the commission to transfer the dams' licenses over to a newly formed nonprofit between the states — the Klamath River Renewal Corporation — that would then decommission and remove them.

"I think you'd be hard pressed to find a case where the dam owner, the states, the federal government and the stakeholders went to FERC with a deal and FERC said no," Tucker said of the federal five-person commission that's currently made up of four Obama appointees and a vacant seat. "I think our chances at FERC are great."

In addition to being united, Tucker said that once philosophies are taken out of the discussion, science is strongly on the side of dam removal.

Nobody understands that science better than Dennis Lynch, who's worked for the United States Geological Survey for more than 30 years, the last seven as the Klamath program manager.

A bureau of the Department of the Interior, the USGS is one of the scientific arms of the federal government. It has no oversight responsibilities, no regulatory capacities. "Our mission is 100 percent science and monitoring and data collection," Lynch said recently by phone. "People give us good questions — like, What would be the impacts of taking these dams out? — and we try to answer them."

In 2009, as the first settlement negotiations were nearing fruition in the basin, Lynch was asked to head a team of about 50 federal scientists from eight agencies looking at the science of dam removal. There were a host of key findings. Science says the dams negatively impact water quality on the river by pooling water in their reservoirs, which in turn warms with high concentrations of dissolved oxygen, providing a breeding ground for toxic algal blooms. The studies also suggest that while removing the four dams won't have much of an impact on the amount of water coming down the river — the dams are designed to generate electricity, not store water — they should leave the river flowing with cleaner, colder water and open up some 400 miles of salmon and steelhead spawning habitat.

Lynch's team also found that the dams are only currently producing about half the energy they were designed to. Additionally, the environmental improvements needed to relicense them — the dams were built decades ago before many environmental laws were put into place — would reduce their power generation by another 25 percent. (That, coupled with the cost of those environmental improvements, is why PacifiCorp has agreed to surrender them for removal, according to company spokesman Bob Gravely.)

Further, Lynch said, when scientists took samples from the estimated 15 million cubic yards of sediment that has built up behind those dams over the decades, they didn't find any concerning levels of heavy metals or chemicals — things like DDT, mercury and dioxin — that would make dam removal hazardous.

In short, the science says dam removal would result in a healthier river with a fairly minimal impact to the power grid.

But — science or no — there are plenty of people convinced dam removal is a terrible idea, the work of "environmental extremists," as Congressman Doug LaMalfa said. Siskiyou County in California and Klamath County in Oregon remain opposed to the deal, and the Klamath Irrigation District, a subsidiary of the Klamath Water Users Association, has already threatened litigation, arguing that it was cut out of the "privately negotiated" new KHSA.

Tucker said he expects lawsuits to be filed. "With (the National Environmental Policy Act) and all these environmental laws, there's a lot of room for litigation," he said. "You can always allege someone broke the law. But that's why we've gone so far above and beyond what's required by law to show the scientific case for dam removal. We look forward to defending this in court because we think we've got the science."

Since the signing day in Requa, things have been moving fast. The newly formed Klamath River Renewal Corporation has already incorporated and is now working on selecting a board of directors. Lynch's team — after largely dispersing for the last few years to other tasks — is busily working on an update to its 2012 Environmental Impact Statement, a "couple hundred-page document to help (FERC) use and understand the work we've done previously," Lynch said.

Looking back on the original Klamath agreements, Tucker's biggest regret is that stakeholders didn't push for congressional action right after they were signed in February of 2010. Instead, they paused to catch their breath and wait for the election year to pass. In the eyes of Tucker and others, it was a fatal mistake, as the Tea Party rose to prominence that November, shifting the political climate in Washington and making dam removal a political lightning rod.

This time, with a presidential election looming, Tucker said the plan is to have the joint proposal submitted to FERC by July 1, enough time to allow for a decision by November. While this thing is supposed to have moved outside the political realm by going into the FERC process, there's always the chance that a new president will appoint new cabinet members with different priorities and the new KHSA — staunchly supported by the current Department of Interior leadership — could get shelved. After all, political winds can shift quickly.

If the KHSA gets the nod of approval from FERC, the new nonprofit corporation will then have to get the federal, state and local permits required to facilitate the largest dam removal project in the nation's history. It's enough to make anyone who's ever applied for a building permit sweat.

"That's a big one," Lynch said. "FERC won't issue a final order until all permits are in place."

That will require permits declaring the project is in compliance with the National Historic Preservation Act, the Clean Water Act and the Coastal Zone Management Act. It will need a wetland delineation from the Army Corps of Engineers and memorandums of agreements with tribes and states. It will also need a host of local permits from counties along the river (including the two staunchly opposed to dam removal) for everything from accessing and using county roads to construction and deconstruction activities.

Somewhere along the way — nobody contacted by the Journal for this story seemed to know exactly when and how — a total of $450 million in funding for dam removal will have to be transferred to the new corporation. About $200 million of that is coming from a surcharge paid by PacifiCorp customers that is being held in an account by the Public Utilities Commission. The other $250 million is from a California water bond and was included in this year's state budget, but it's unclear exactly what the process is to transfer those funds to the new nonprofit and whether it would require an act of the state Legislature.

Once the nonprofit has all permits and funding in hand, it would return to FERC seeking a final license transfer and decommissioning order.

"FERC will require that the plan to do this is something that they can accept," PacifiCorp spokesman Bob Gravely said. "Certainly, they've approved other dam removals but the plan and the financing and the risk mitigation are going to have to pass muster with FERC, and all of that still has to happen."

With a permitted, funded project and a final order from FERC, all that's left is to successfully execute the removal of a combined 425 vertical feet of dams in a single year, 2020.

Because there's an estimated 15 million cubic yards of sediment built up behind the four dams, Lynch said models indicate the best course to minimize impacts on fisheries is to take them all out at once. As a part of removal, most of that sediment — about 85 percent of which is fine silt and clay — will be released into the river. There's no question that will have a negative impact on fish.

"The sediment concentration will be high enough to damage fish, high enough to be lethal to some fish," Lynch said. But salmon have three-year lifecycles and only one cohort is in the river at any given time, Lynch explained, so it's better for the fishery as a whole to have a large impact on a single cohort than to have recurring negative impacts to multiple generations coming into the river to spawn. "Three years in a row is worse than hitting them really hard in one year," Lynch explained.

The plan, as Lynch outlined it, is to start drawing down the reservoirs with the dams still intact, in the middle of winter, when the river is flowing at its highest. That way, the sediment released from the reservoirs has the best chance of quickly flowing down stream and out into the ocean. Because 85 percent of that sediment is silt, Lynch said, models show most of it will flow out to sea within three or four months. Doing this during the winter, Lynch said, also means most salmon will either be up in the Klamath's tributaries or out at sea, which should minimize impacts.

The other 15 percent of sediment is made up of heavier materials, like sand, gravel and cobbles, Lynch said. Models show this material will move downstream more slowly and only when the river swells with winter rains. There's enough of this stuff that it will fill a foot-and-a-half layer in the river's channel for a couple of miles downstream of Iron Gate Dam, which sits closest to the Klamath's mouth.

"Some people think that's going to be a mess, but, well, no, it's really not," Lynch said, adding that biologists have been adding gravel downstream of dams for years anyway to mimic natural conditions and aid fish spawning.

There is some concern, however, about the massive release of fine sediment into the ocean, as some fear it will hit the mouth of the Klamath, catch a northward current and wind up deposited 15 miles north in the Crescent City Harbor. Lynch said his team didn't run specific models to vet this concern, but said it did look at "other studies of sediment plume dynamics in Northern California" and determined it's possible, with the perfect combination of currents, flows, tides and winds.

But, Lynch was quick to point out, the KHSA sets aside $65 million for the nonprofit overseeing removal to spend on mitigation, which could include a dredging of the harbor, if needed. And that underscores a point Lynch was careful to make several times: There will be adverse impacts that come along with this dam removal, possibly even some unforeseen ones. "You don't set aside $65 million for mitigation without expecting that there will be some types of things that will have to be done (after the dams come down)," Lynch said.

Physical removal of the dams will begin in spring and stretch through the summer. Lynch said it's preferable to remove dams in the drier months, when the river is flowing lower and slower, banks are more stable and it's generally easier to pull off a massive construction project in an ecologically sensitive area. And, because each of the four dams is different, each requires a different removal strategy.

Iron Gate Dam is a 189-foot, earthen embankment dam, meaning it's mostly built up of compacted earth under waterproof surface. After the reservoir is drawn down, Lynch said, crews will begin excavating the dam from the top down in June. Copco 2 (the next upriver from Iron Gate) is a 33-foot dam built of concrete, and is slated to be removed "via mechanical means" beginning in May, according to Lynch.

Copco 1 (next upriver) is a 135-foot-tall concrete dam that will be removed in 8-foot layers beginning in the winter and extending into April, with each layer being shaved off with a combination of blasting and heavy equipment. Lynch said removal work on Copco 1 can begin during the winter because there's no risk of dam failure with the removal plan, and the structure is easily accessible for work crews. The last dam, J.C. Boyle, is a 68-foot dam built of concrete and earthfill embankment. Some blasting might be necessary, Lynch said, but the majority of the structure will be removed by excavators.

Again, Lynch and others stressed, this work will come with some impacts. Removal of the dams is expected to change the river's floodplain slightly, meaning about a dozen buildings and homes along its banks may need to be moved. Additionally, there will be enough silt and debris in the water the year of removal that some systems pumping water out of the river will see their screens clogged, necessitating replacement. Around the dam reservoirs, some groundwater wells might go dry and need to be drilled deeper. And, they cautioned, some fish, and maybe even other species, will die. But forecasts of environmental disaster simply haven't come to fruition with other dam removal projects.

Tucker said the new nonprofit will be purchasing a private insurance policy to cover anything that goes wrong in excess of the set-aside mitigation funds, and he said many of the contractors tapped to remove the dams will be bonded with their own insurance policies and share liability. The success of recent dam removals elsewhere, Tucker said, has made insurance more affordable and contractors more willing to shoulder some of the liability.

Lynch said there's no doubt there will be negative impacts when all those millions of cubic yards of sediment start flowing downstream and the dams that have clogged the river for decades are finally pulled. But, he said, positive impacts will follow almost immediately.

"I think one thing a lot of people lose sight of is they think way too much in the short term," he said. "This is trying to set up the Klamath for the next decade, or the next century. That's really what fisheries and ecosystems are about. In the short-term, there are some consequences but we think we understand them and we have mitigation funding available for some of the problems in the short term.

"In the long term," Lynch continued, "there's no information out there that says this is the wrong idea."

The night before the signing ceremony at the mouth of the Klamath, O'Rourke and the Yurok Tribe hosted a salmon dinner for all the state, federal and tribal officials coming to the reservation. "All our visitors that come here to Yurok country, I'll say, eat fish. That's what we eat," explained O'Rourke. "Yurok and fish go together, hand in hand. You seldom hear of one without the other. ... If the river's sick, everything along it that depends on it is sick, including our people."

The river has been in failing health for decades. The 2002 fish kill, during which some 50,000 salmon contracted gill rot in the Klamath's warm waters and died, has been the most prominent symptom, but recent drought years have only exacerbated the problems. This year, Huffman pointed out at the signing ceremony, salmon projections are so bleak local tribes have only been allotted a harvest for the season amounting to less than one fish per tribal member.

This has a cascading effect on local tribes. At the signing ceremony, Karuk Tribal Chair Russell "Buster" Attebery said he grew up on the river, recalling that as a kid it was a great honor to be tasked with providing a meal for his family. "Being able to fish for my family was a source of pride and self esteem for me, it was an important part of my maturation as a man," he said, adding that recent generations haven't been able to play that role of provider from a young age, haven't had the opportunity for their elders to teach them the traditional way to be stewards of the river. "That loss leads to a loss of culture, a loss of personal identity, lost economic opportunities and, no doubt, plays a role in the epidemic of depression and drug abuse we see in our communities."

About a week after the ceremony, O'Rourke reflected on the morning spent under a cloudless blue sky near the mouth of the river he loves. "I think it was a historic day, without a doubt," he said. "It marks a new beginning of new relationships and strengthening old relationships to achieve something worth achieving, and that's dam removal, to restore the river to its historic state so it can begin to heal."

O'Rourke stopped short of calling it a great day. That judgment will have to wait, after all, until the sun finally sets on the four Klamath dams that choke the river on which his people depend.