Officials with the National Marine Fisheries Service last week visited crumbling Roy's Dam on San Geronimo Creek and decided a fish-rescue operation was unnecessary, but probably couldn't hurt.
"The fish seem to be doing okay, " said Jim Bybee, northern area coordinator for the Fisheries Service. "It's a very short-term problem. I doubt if any of the fish are being killed."
Near a well-traveled bridge along San Geronimo Valley Drive, ten vertical feet of concrete stand between some salmon and spawning grounds upstream.
Although there is a fish ladder at one side of the dam, dozens of the coho detour into water that funnels through a broken concrete apron below the dam. Once past the broken apron, the fish thrash about in shallow water in a futile attempt to jump the dam.
However, many fish have been seen spawning upstream from Roy's Dam, Bybee said. And as stream flows recede and water stops flowing over the dam, they eventually go back downstream to find the fish passage, he added.
But because the salmon may get bruised and tired on the apron, "it probably wouldn't hurt" if they were helped over the dam, Bybee said.
Fisheries Service officials plan to visit Roy's Dam again next week to decide what action the property owner should take to repair the area, Bybee said. San Geronimo Creek skirts the southern end of the golf course, which is in escro for sale to Evergreen Alliance of Texas.
The Fishery Service takes charge of protecting coho on Dec. 30, when the fish is formally listed as a species threatened with extinction. Until then, Baybee said, any action would come through California Fish and Game.
"By Friday [the dam] was a pretty boring place to be," said Fish and Game biologist Bill Cox, who has worked on San Geronimo and Lagunitas creeks for 14 years.
"I'll wager that all those fish at the dam went up the ladder. Of those that went back downstream, there's a real good chance they will go back up in a day or two," he said.
Although studies and surveys of the area are incomplete, Cox said there is no urgent problem with fish passage.
Now at the halfway mark in the spawning season, more than 100 fish and 20 redds, or nests, have been counted above Roy's dam, said Lanette Davis, a fishery biologist with Trihey and Associates. Trihey is a Concord-based environmental consulting firm working to survey the creek population for Marin Municipal Water District.
Last year there were only six redds in all of San Geronimo Creek, which stretches from the Ink Wells at Lagunitas to Woodacre, although the creek through Woodacre is not surveyed, Davis noted.
This year, 57 redds have been counted in the creek so far and, except for Woodacre, the area above Roy's is nearing full capacity, she said.
Still, some residents who watch the area during storms insist the dam presents a dangerous obstacle between fish and their spawning beds.
"[Last week] I went by and saw all these fish just stuck there," said Forest Knolls resident Todd Steiner. "They could get up speed and try to jump the dam, but would get smashed into the concrete and washed downstream."
Steiner and more than 350 people are petitioning Fish and Game and other agencies to repair the dam apron. They also suggest that a floating net might guide fish to the ladder, or that the fish be netted and helped upstream. Steiner said he has applied to Fish and Game so he could handle the fish.
"Obviously it is a man-made barrier, and those fish should be able to go wherever the hell they want," said Steiner, a former National Park Service reptile expert. "I would not catch fish at the coast and haul them up there, but all we're trying to do is undo human intervention ... and level the playing field."
Roy's dam predates the fish ladder built in 1954 with the help of San Geronimo resident Willis Evans, who was then a fisheries biologist with Fish and Game.
"The dam was probably built to prevent heavy soil erosion upstream," said Evans. "The dam is still serving a purpose, so there's not an easy solution by removing it."
Evans, once in charge of fisheries in 13 counties, said Lagunitas Creek and its tributaries 40 years ago were habitat for 5,000 to 6,000 salmon and steelhead.
At that time, Marin Municipal Water District built Peter's Dam and formed Kent Lake while eliminating 50 miles of spawning and nursery area, Evans said. Today dozens of the coho gather at the foot of Peters Dam, which is in a less-visible area of the creek than Roy's dam. There are only 500-600 coho left in the Lagunitas Creek area, Evans said.
"Anything and everything should be done to help them complete their life cycle," Evans said. "Every pair [of salmon] that gets up here and tries to improve or increase the run is very important to us."
However, Cox of Fish and Game said human intervention at Roy's dam may not be in the best interest of the fish.
"If you have 200 fish going past and one can't make it, I don't know if you should intervene," Cox said. "You could pollute the genetic stock, so to speak."
Paul Siri, a principal investigator in a statewide DNA survey of salmon, said that helping the fish upstream might result in a sort of artificial selection.
"We are taking tissue samples of fish above and below [Roy's dam] to see if there is a serious genetic loss. If the fish are brothers or sisters the loss is not as [genetically] significant," Siri said.