An upstream battle

Looking down from a bank high over Butte Creek, Allen Harthorn pointed to about 50 spring-run chinook salmon idling near the surface of a deep, clear pool. Occasionally, a fish reacted to some perceived danger and disappeared with the swish of a tail.

That’s basically what they’ll do all summer—hold in cold water without eating, conserving energy until September or early October.

By then, the silvery hue they had as ocean fish will have turned red or yellow and they will start scouting out shallow, gravelly sections of the creek in which to spawn. After the eggs are laid and fertilized, the adults will die. The fry will hatch a few months later and eventually begin the journey to the Pacific Ocean, starting the cycle over.

Harthorn watches it all happen from his 15-acre, creekside property flanked by the spectacular walls of Butte Creek Canyon. He is executive director of the Friends of Butte Creek, a nonprofit group that advocates for environmental review, protection and enhancement of the watershed.

“We’re the only people on the creek on a regular basis, keeping people informed on how the fish are doing,” he said.

It’s important work, he said, because Butte Creek is a special place. The Central Valley’s population of chinook salmon has collapsed over the last several decades, leaving only three creeks in California—Butte, along with Deer and Mill creeks in Tehama County—with self-sustaining salmon runs (i.e., they are not augmented by fish from hatcheries). Of the three, Butte’s salmon population is the most robust. Biologists consider the creek to be the greatest stronghold of salmon in the valley and a shining example of how the species can adapt and recover.

In other words, the creek that runs through Chico’s backyard is home to one of the last great salmon runs in California.

Butte Creek’s ecosystem is not in a natural state, however. The spring-run salmon depend on releases of cold water from the DeSabla-Centerville Hydroelectric Project, a 20-megawatt hydroelectric system owned and operated by Pacific Gas & Electric Co. that encompasses more than 20 miles of canals, flumes and tunnels. For more than a century, the project has connected two distinct watersheds, diverting water from the west branch of the Feather River to three small powerhouses and providing additional flows to Butte Creek.

This is critical for spring-run salmon because they need cold water to survive the summer months and complete their spawning cycle, said Clint Garman, an environmental scientist for the California Department of Fish and Wildlife (DFW).

“It’s huge for the fish,” he said. “Without that cold water coming over from the Feather River, who knows what would happen to them? It wouldn’t be good.”

He may find out: In February, PG&E announced a plan to sell the DeSabla-Centerville project, triggering concerns from environmental groups about what would happen if the utility company fails to find a buyer and instead decommissions the powerhouses. In that scenario, Garman said, the cold-water releases would cease—and the spring-run salmon would suffer.

Throughout California, the long-term outlook for salmon is dire, according to a report titled “The State of Salmonids II: Fish in Hot Water.” Compiled by nonprofit environmental group CalTrout and the UC Davis Center for Watershed Sciences, and released in May, the report provides a snapshot of the status of 32 types of fish native to California. (The first report was released in 2008.) The authors say that, largely due to five years of historic drought, all 31 of the remaining species are worse off today than a decade ago.

“If present trends continue,” the authors warn, “74 percent of California’s native salmon, steelhead, and trout species are likely to be extinct in 100 years, and 45 percent could be extinct in 50 years.”

In addition to the overarching problem of climate change, the report identifies various human-induced threats such as dams, agriculture, estuary alteration and urbanization. In a statement, Curtis Knight, executive director of CalTrout, said, “The health of our native fish is a reflection of the health of our rivers and streams. Declining fish populations indicate degraded waters, which threaten the health and economic well-being of all Californians.”

As for solutions, the report emphasizes that saving the salmon relies on human investment into currently productive ecosystems and “restoring function to once-productive but highly altered habitats.” For instance, research conducted by CalTrout demonstrates that agricultural activity and healthy fish populations are not mutually exclusive—that, in fact, off-season rice fields can mimic natural floodplains and support rapid growth of juvenile salmon.

Jacob Katz, an ecologist with CalTrout, has studied how seemingly artificial environments can support healthy fish populations. During a phone interview, he pointed to Butte Creek as an example. After crossing under Highway 99 near Durham, the creek continues south for about 60 miles before entering the Sutter Bypass, a pair of diversion ditches south of the Sutter Buttes that were created for flood control and connect to the Sacramento River.

This stretch is the “largest functional floodplain habitat left in the Central Valley,” Katz said. It serves as something of a nursery for young fish. In such a food-rich wetland habitat where the pickings are easy, the fish can double their weight every week, he said, and they often linger for months before heading out to sea.

Bigger fish have greater chances of surviving the open ocean and returning to spawn, usually in three to four years. Neither Deer nor Mill creek has a long flood plain in which their respective populations of fish can eat and gain size. Also to the detriment of the salmon, those waterways have much longer gauntlets of predators and possible diversions to run. Butte Creek is unique in that regard—95 percent of the Central Valley’s floodplain habitat that existed prior to European settlement is gone, mostly due to agricultural development.

“Butte Creek connects all of the links in the habitat chain,” Katz said. “It is the only major stream in the valley that has all the necessary habitat to complete the freshwater life stages of salmon.”

“We think that’s the big advantage Butte Creek has over its counterparts,” Garman said.

California’s historically abundant coastal chinook salmon was federally listed as an endangered species in 1999, after decades of overfishing and habitat degradation decimated the population.

Around that time, Garman started studying Butte Creek, gaining a first-hand perspective on how the ecosystem has benefited from extensive restoration efforts. Since 1995, a multitude of public and private stakeholders have spent a combined $60 million to retrofit fish ladders, acquire riparian habitat, adjust water agreements with agricultural users and install barriers to keep fish from straying into agricultural ditches.

As a result, the spring-run salmon population has rebounded spectacularly. From 1960 to 1995, Butte Creek’s base population averaged about 360 fish; since, it’s averaged nearly 8,000, peaking in 1998 at more than 20,000 salmon (see chart below).

Katz says the success of Butte Creek serves as a working model for improving all of the stream habitats in the Central Valley. “It takes groups of farmers, water districts and government agencies to roll up their sleeves and do the work,” he said, “and Butte is a beacon for that. You can do the work and expect salmon to respond.”

A recent snorkel survey conducted by DFW and the National Oceanic and Atmospheric Administration tallied only 926 spring-run salmon in Butte Creek, but that in itself isn’t alarming, Garman said. Year-to-year fluctuations in fish populations are normal.

“These fish are always going to have certain stressors—some that we can control and some we can’t,” Garman said. “Poaching and habitat degradation is something we can control, and we try to, but we can’t control the drought cycle we just went through. That was really tough on the fish. Obviously, they need water to survive.”

That basic truth is why, of all the threats facing salmon in Butte Creek, the greatest one may be presented by PG&E’s plan to sell the DeSabla-Centerville project, Garman said. In the dry months from June through August, diversions from the Feather River supply up to 40 percent of the water in the creek.

PG&E’s withdrawal from Butte Creek is a matter of dollars and cents, said Mike Schonherr, the company’s director of strategic agreements. Quite simply, small hydroelectric systems like the three powerhouses that make up the DeSabla-Centerville project no longer pencil out for the utility giant. California’s solar boom has drastically changed the landscape of the renewable energy marketplace, lowering the market prices for clean power. Meanwhile, regulatory requirements make the hydroelectric facilities increasingly expensive to operate.

The aging structures also require a lot of maintenance. “Any system that is 100 years old is going to have its issues,” Schonherr said.

For instance, the 6.4-megawatt Centerville Powerhouse has been out of service since 2011, when PG&E determined that the penstock—the pipe that carries water downhill from the canal to the powerhouse—couldn’t handle high water pressure, said spokesman Paul Moreno. As a result, the company cut off the water that used to flow into the Centerville flumes, leaving only the DeSabla (18.5 megawatts) and Toadtown (1.5 megawatts) powerhouses in operation.

The bottom line, Schonherr said, is that PG&E has a fiduciary responsibility to provide cost-efficient power: “We have to look at what is in the best interest of our customers.”

In February, PG&E submitted a letter to withdraw its application for a new license with the Federal Energy Regulatory Commission (FERC) to operate the DeSabla-Centerville project. So far, five entities have expressed interest in buying the system, including independent power producers such as KC Hydro out of Missouri and New Jersey-based Eagle Creek Renewable Energy, as well as the Paradise Irrigation District.

Whether any of the interested parties has the resources and wherewithal to maintain such an extensive and aging water-transfer system remains to be seen, Garman said. He worries the next owner of the system won’t be as responsible as PG&E.

“For as long as I’ve worked on Butte Creek, PG&E has been really good about working with us to preserve this salmon run,” he said. “They’ve always held the fish in high regard and are very responsive to fishes’ needs.”

Any sale and transfer needs approval from FERC, among other regulatory bodies—processes that could take up to five years. Furthermore, the new licensee would be held to the same laws and regulations as PG&E, including the Endangered Species Act.

“We’re very interested in ensuring that this goes as smoothly and as transparently as possible,” Schonherr said. “Our objective is to find a competent and capable buyer to take over our responsibilities on the project.”

In the scenario that PG&E doesn’t find a buyer, FERC likely would order the company to decommission the project, Schonherr said, beginning a years-long process of either permanently shutting down the powerhouses or physically removing them from the creeks. Schonherr declined to speculate on how that would affect fish—“those plans would be evaluated,” he said, noting that the Endangered Species Act would apply to the decommissioning process.

“PG&E cannot arbitrarily shut off the water,” he said.

With the future of the hydroelectric facilities uncertain, progress made toward restoring Butte Creek’s salmon runs is hanging in limbo, Katz said.

“PG&E’s move to withdraw from the DeSabla-Centerville project focuses a light on the precarious nature of trying to manage fish and wildlife in a heavily altered environment,” he said. “Butte Creek is our big success story, yet it’s based on one water transfer from the Feather River.”

Harthorn, for one, is hopeful that someone will assume responsibility of the DeSabla-Centerville project, whether that be a private energy company, a nonprofit environmental group or a government entity.

He and Friends of Butte Creek have set an objective to ensure that “whoever takes it over does what needs to be done” to protect the fish, because they are surely in for serious challenges in the decades to come. But he believes in the resiliency of the salmon as a species, due in no small part to watching the spring-run populations in Butte Creek rebound in his own backyard.

“We’re certainly going to see a steep decline if the water temperatures get too high; we’ll be down to some really small remnant populations,” he said. “But they have survived for hundreds of thousands of years in this creek. We may be gone in 150 years, and the fish will come back.”