Moment of truth for Martinez beavers MARTINEZ

The tale of the Martinez beavers heads into a new chapter tonight when the City Council considers ways to stop the busy critters from chewing through $10 million of flood-control work.

Council members are expected to discuss seven options for controlling the beavers, who took up residence in Alhambra Creek 18 months ago and whose dams have wreaked havoc on the city's pricey new landscaping and elaborate flood-control measures.

The options include widening the creek around the dams, installing a bypass pipe and raising the floodwalls. The costs range from $2,000 to more than $100,000.

"We looked at plans that enable us to coexist with the beavers in a way that does not bring increased flood risk to the downtown," said Councilwoman Lara Delaney, who sat on the Beavers in Alhambra Creek subcommittee.

"We're the city of John Muir - we're a green community," she said. "Not only are the beavers good for the environment, they're good for education and tourism. They're bringing people to downtown."

Last fall, the beavers' future was not so rosy. Fearing that the animals' obsessive handiwork would cause the creek to flood in the rainy season, the city considered killing the beavers and removing their intricate mud-and-stick dams.

But public outcry was so great that the city agreed to look at other options. The committee submitted its 118-page report last week, and the council will listen to public comment before making a decision, probably at its next meeting.

"There's a lot of excitement about the beavers," said public works director Dave Scola. "We've had busloads of people come and watch them. School field trips. Kids. Anyone can see them - they're right there by the bridge."

The beavers' biggest dam is between Escobar and Marina Vista bridges, about 30 feet wide and at one time 6 feet high. A few weeks ago, the city hired a beaver expert from Vermont, wildlife biologist Skip Lisle, to install a pipe through the dam to lower the water level and trick the beavers into not building so high.

It worked, but then the beavers started building another dam about 100 yards downstream.

Still, beaver control is not rocket science, Lisle said.

"If we can put a man on the moon, we can outsmart beavers. They're not very good at deductive reasoning," he said. "They're very single-minded."

Beavers build dams so they have a pool to dive into to escape from predators, Lisle said. They also use the pools to easily transport tree branches, which double as lunch and building material.

The nocturnal animals spend most nights compulsively patching and weaving their dams. When one is finished, they'll start another. After a rainstorm, they'll forgo sleep to repair the damage, diving for mud and collecting sticks and branches.

In Martinez, the beavers have chewed through half the willows and other creekside landscaping the city planted as part of its 1999 flood-improvement project, said Scola.

The saga started in late 2006, when a male and female beaver arrived in Alhambra Creek, probably from the Sacramento-San Joaquin River Delta, Scola said. Within a few months they had three babies, although one died from parasites.

Beavers have also moved into creeks in Pittsburg, Elk Grove and other cities near the delta, a sign they're "gradually clawing their way back to their ancient range," Lisle said.

"North America is one giant beaver habitat," he said. "What's happening in Martinez represents the survival of a native species we almost obliterated."

Beavers, mild-mannered vegetarians who aren't shy of people, were once common throughout the Bay Area but were hunted to near extinction in the early 20th century. The population is slowly recovering, as beavers find they can flourish in urban environments, Lisle said.

Sherri Tippie, a beaver trapper from Colorado that the city consulted, said beavers are increasingly common in cities throughout the United States.

"People can be so anal about what they think our creeks should look like," she said. "They want creeks to be static. But beavers belong in creeks as much as water does."