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The unfortunate death of more than half the spring-run salmon on Butte Creek is bad news for both the salmon and PG&E. Another outstanding run of the threatened species, estimated at nearly 10,000 adult salmon, entered Butte Creek Canyon in the spring. The water was high and cool thanks to late-spring storms. The problem is, spring-run salmon have to survive an entire summer in the canyon waters because they don't spawn until September and October. The usual cool canyon pools warmed drastically during a hot spell in July, and an estimated 5,472 salmon died. The warmer water makes the fish sluggish and more susceptible to disease, and the large run also meant more crowded conditions in the holding water, which added to the strain on the fish. Roughly 1,700 salmon died last year for most of the same reasons, but it wasn't such a large chunk of the run. An estimated 8,785 spawned. Why are the fish kills bad news for PG&E? Well, the company's relicensing process on the Butte Creek project just began. Part of the process is public input, and people who would like to see PG&E take less water out of the creek for power generation now have more ammunition. The issue is a stretch of water from Quartz Pool, a natural barrier high up the canyon, down to Centerville Powerhouse. Roughly half the creek is diverted into a long canal, runs through a powerhouse, then is dumped back into the creek. That leaves 40-50 cubic feet per second (cfs) all summer in the "low-flow" section of the creek. Downstream of the powerhouse, where the canal's water is returned to the creek, the flow averages 130-170 cfs all summer. Unfortunately, many salmon hold in the low-flow section. That's where most of the fish died. It's not until now, when the water cools and the fish start thinking about spawning, that many fish slide downriver looking for places to dig redds. Salmon will spawn from Quartz Bowl all the way down to Parrot-Phelan Dam, also called Okie Dam. Much of the fish kill this year was happenstance. The water was flowing just as high as usual, but the temperature was, on average, 2-3 degrees higher in August than usual. On July 1, the water temperature at noon was 64.4 degrees at the U.S. Geological Survey's gauging station downstream of the Centerville Powerhouse. On July 30 at noon, the temperature was 74.5. Although it slowly cooled in August, the damage had been done. The large run also played a role. Nobody can do much about the air temperature or the size of the run, so people turn to PG&E - the only variable. The utility company is mandated to leave at least 40 cfs in the creek's low-flow section and regularly exceeds that minimum. But before we paint PG&E as the demon, keep in mind that the company diverts 50-90 cfs of water all summer from West Branch Feather River into Butte Creek, via DeSabla. Without that cooler water from West Branch, Butte Creek would be even warmer. Keep in mind, too, that this six-year run of fish on Butte Creek - representing two salmon life cycles - is the best in recorded history. The state Department of Fish and Game has been taking fish surveys since 1954. During a six-year run in the early '60s, the run average more than 3,500 fish annually. But the numbers began to plummet, hitting low points of 10 in 1979, 50 in 1983, 23 a year later and 14 in 1987. The threatened species listing prompted many positive changes in water diversions, dams and screens downstream, and the results have been phenomenal. The last six years have seen an average of nearly 8,500 spawning fish. That bodes well for the future. With the West Branch diversion, PG&E created a larger Butte Creek, which has enhanced the salmon run. Now PG&E is paying the price for that success and is in a can't-win situation. People should remember that before blaming PG&E for the salmon deaths. PG&E has a license to operate until 2009. It's doubtful any government agency can force PG&E to leave more water in the river until then. But if PG&E offers to leave, say, 50 cfs in the low-flow section next summer so it can monitor the effect on fish there, that would be an olive branch that may make the relicensing process go just a little easier. Then again, there's always the danger that no matter what PG&E leaves in the creek, people will want more.
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