Molly Samuel/KQED

Englebright Dam is not part of any of the hydro projects on the Yuba River, but it's surrounded by them.

When most of the dams in California were built, there were few, if any, safety or environmental regulations governing how they operated. Now most hydropower projects, whether they’re owned by local agencies or power companies, need licenses from the Federal Energy Regulatory Commission, or FERC. (Federal projects don’t require FERC licenses.) Licenses are good for 30 to 50 years, and licensees don’t have to keep up with, for instance, environmental laws passed in the intervening years. So when a hydropower project does come up for relicensing, there’s a lot to catch up on.

I described some of the relicensing process in a radio story for The California Report for Climate Watch’s “Water and Power” series. Dennis Smith, the Hydropower Relicensing Manager for Region 5 for the Forest Service, gave me a taste of how complicated relicensing is when he showed me a flow chart [PDF] of how the process works. It has 39 boxes on it, each a discrete step. A typical application takes at least five years to complete. Some take much longer.

“You could have a child and he would be in the first grade by the time you got a license for a dam,” Smith said.

One reason why relicensing is so complicated, is that the hydropower projects themselves are incredibly complex. We are not talking water wheels here.

Yuba-Bear and Drum Spaulding Projects Schematic (Modeling Version)

This map shows the Yuba-Bear and Drum-Spaulding hydroelectric projects, owned by the Nevada Irrigation District and Pacific Gas and Electric, respectively. These two projects, on the Yuba River in the Sierra Nevada, are so entwined, they’re being relicensed together. Combined, it’s the most complicated hydropower project in the state — possibly in the nation.

“You could describe it as a plate of spaghetti tossed on a map, with meatballs. It almost looks that random until you get to know it,” Steve Rothert, the California Director for environmental group American Rivers, told me. And it’s not the only relicensing happening on the Yuba right now. The Yuba County Water Agency’s Yuba River Development Project is also going through the process.

“Here on the Yuba there are three different hydro projects going through relicensing, that involve over 30 dams and almost 20 powerhouses,” Rothert told me. “And within the next three years these dams will have new licenses that will govern the next 30 to 50 years.”

So the stakes are high when Rothert advocates for better habitat for fish and other animals during relicensing. He’s primarily trying to negotiate for higher flows — for more water to be released into the river. And with a project like Yuba-Bear Drum-Spaulding, he and all the other stakeholders aren’t just trying to agree on a single flow. There are nearly 50 sections of river to evaluate, at different times of year and during all types of years. (The flows during January in a wet year are not the same as the flows during September in a dry year.)

And then there’s the irony of where I interviewed Rothert about hydropower relicensing. We stood overlooking Englebright Dam, built by the Army Corps of Engineers to block sediment from gold mining. Fish can’t get past the dam, and the National Marine Fisheries Service issued a biological opinion [PDF], saying it jeopardizes spring-run Chinook salmon and other species. But it’s not a hydropower dam — and it’s owned by a federal agency, anyway — so it’s not in FERC’s jurisdiction; it doesn’t have to go through relicensing.

And yet, Englebright, too, is linked to the hydropower projects on the Yuba. Two powerhouses are just downstream of it — one owned by PG&E, the other by the Yuba County Water Agency. To misquote John Muir, “When we try to pick out anything by itself, we find it hitched to everything else in the Yuba River.”

We’ve mapped all of California’s hydropower dams as part of our series on “Water and Power.”

Craig Miller

PCWA's Ralston Powerhouse on the Rubicon River in Placer County. California typically gets about 15% of its electricity from hydro facilities inside the state..

While much is uncertain about California’s warming climate, there is little doubt that it’s already changing the fundamentals of how most of us get our water. In fact, the Bureau of Reclamation has estimated that the Sierra snowpack could be reduced by half as soon as a decade from now.

And that has some far-reaching implications that could even show up on your electric bill.

“When you hear people talk about a depleted snowpack, it’s because of warmer temperatures and the snow just cannot stay in the hills,” says Robert Shibatani, a hydrologist and consultant to numerous government agencies. He says the “hydrograph” for California — the “usual” pattern of precipitation and runoff — is already changing. “There’s no question about it,” he told me in a recent interview. “That’s not an if. It’s not even a when, because I can tell you the when. It’s happening now.”

Shibatani says it’s not that we’ll get less precipitation, necessarily, but warming temperatures will mean more of it falling as rain at higher elevations. And the relatively steady runoff we’ve come to count on to fill the reservoirs and spin the turbines throughout the summer and fall will be compressed into the late winter and early spring.

“What it’s gonna mean is that we’re gonna spill more often,” says Einar Maisch, strategic planning director for the Placer County Water Agency. “And that means we’re gonna lose generation.”

Maisch says his agency is already enlarging spillways to accommodate bigger springtime rushes of water — and he’s prepared to see power generation taper off by 5-to 6 percent at his facilities, which generates more than 200 megawatts of power, purchased by PG&E.

“Water that goes over the top [during those high-pulse periods] does not go through a turbine,” he says.

At other times, there may not be enough runoff to spin the turbines reliably. We had a sneak preview of that during those three dry years in a row that we had recently. Overall, during that time hydro generation was roughly cut in half, says water analyst Juliet Christian-Smith at Oakland’s Pacific Institute. “That has a price tag and an environmental impact as well.”

Craig Miller

PG&E's Belden Powerhouse on the upper Feather River. This stretch of the Feather has so many hydro plants on it that it's become known as the "Stairway of Power."

She ran the numbers and found that as utilities were forced to switch some of the load to natural gas-fired plants to make up the difference, “The cost to electricity consumers was about $1.7 billion dollars.” That’s billion, with a “B.” And here are some more billions from the same time frame: 13 billion additional tons of carbon dioxide emissions because, well, burning natural gas emits CO2 and hydropower does not. Christian-Smith says that, “Given the impact of this drought on our energy production possibilities and the costs that we had to pay for energy, it’s important to think about what a longer and more severe drought might do.”

And there’s another rub, says PCWA’s Maisch. “Hydro is unique.” Not only is it the cheapest form of power imaginable, but it’s the most “dispatchable,” as they say, when utilities need to make quick adjustments to meet fluctuations in electrical demand.

On a tour of one of his agency’s powerhouses, near where the Rubicon River meets the MIddle Fork of the American, “Throttling the needle valves on the Ralston generator over there can change the amount of flow by 50% within 10 minutes. It gives us a tremendous ability to ramp in counter-flow to the changes in the grid.”

That’s not a trivial matter as utilities try to balance a power grid with an increasing percentage of on-again, off-again renewables, like wind and solar. PG&E’s David Moller, who heads the National Hydropower Association, said in a recent company publication that, “The operating flexibility of hydropower is essential to grid reliability and integrating intermittent renewables.” He’s calling for an expansion of hydro, pointing out that of the 80,000 dams across the country, just three percent currently have hydro installed.

But any expansion in California will be a tricky proposition given the environmental sensitivities of the state’s mountain regions. Most projects have recently gone through — or are going through — tortuous renewals of their federal licenses, which usually result in a net reduction of power generated to accommodate environmental concerns. And in California, utilities can’t count hydropower toward their renewable energy targets.

Hear Craig’s companion radio report Monday on KQED’s The California Report. We’ve mapped all of California’s hydropower dams as part of our series on “Water and Power.”

PG&E substation near San Jose. The drop in emissions applied to both power generated in California and imported from neighboring states. (Photo: Craig Miller)

If you’re ready for some good news on the climate front: California’s carbon emissions from power generation dropped in 2009 and 2010.

That’s according to a new analysis from Thomson Reuters’ Point Carbon that looked at power generated here in California, as well as electricity imported from out of state.

According to the report (available by subscription only), emissions were down 12% over the study period. Part of the drop, not surprisingly, was due the global recession and the state’s slowed economy in 2009. But the study found that even when the economy started growing again, emissions continued to decline.

Sound mysterious? Not really, according to study co-author Ashley Lawson.

“It was actually the weather,” she said. “It was relatively cooler in 2010, so people were running their air conditioners less, and it was also relatively wetter, so there was more water available for producing hydroelectricity.”

So, despite a slight uptick in the economy, demands on the electrical grid were less due to milder temperatures — and the state was able to meet more of its electrical needs with carbon-free hydropower, which meant less demand for coal or gas, and hence, fewer emissions.

Lawson said that new solar and wind installations in California also contributed to the drop in emissions, and, while they played a smaller role than hydropower (just 15% of the reductions), she said, in one way, they are more significant.

“Hydro power will only generate electricity as long as the conditions stay good for it,” she said. “It’s a temporary situation. Renewables like wind and solar will lead to keeping emissions low because they aren’t going to go away.”

The study also looked beyond power generation and analyzed all of the stationary sources in California that will be subject to the state’s cap & trade program as of 2013. That includes power plants as well as manufacturing facilities and other large industrial plants that emit more than 25,000 tons of greenhouse gases per year. The study found that emissions from those 343 sources also experienced a decline of 11% over the same period, although the results varied by sector. Emissions from mining fell nine percent, and those from cement, lime, and glass production fell 34%. Meanwhile emissions from chemical plants rose 21%.

The study did not track emissions from cars, trucks and other transportation sources. Electricity generation is about a quarter of California’s total carbon emissions “pie.”