Wildlife

Beavers in Martinez

July 11, 2008

Several beavers have taken up residence in downtown Martinez, and this summer may be the best time to see them — before they become more famous and attract bigger crowds or get forcibly ousted by the local government.

But can beavers, beaver dams, and the small city of Martinez peacefully co-exist? That’s the question that the city government and local residents have been asking themselves since 2006, when a pair of beavers moved into lower Alhambra Creek in downtown Martinez.

Warm summer evenings, when the beavers are most active, is the best time to catch a glimpse of these curious animals that have captivated a community. The beavers have gained much attention following their arrival—they now have their own web site, they’ve starred in YouTube videos, they will be featured in a Discovery Channel special, and there is a new children’s book about them.

But their time in Martinez may not last.

In the winter of 2007, the beavers built a dam across the narrow, channelized creek near the intersection of Castro and Escobar Streets. Many local residents were delighted with their new furry neighbors. However, some property owners and the city became concerned that the beaver dam could increase the frequency and severity of flooding downtown and that the beavers’ feeding and burrowing could increase bank erosion.

Flooding has been and continues to be a serious problem for Martinez. In fact, until a $10 million flood control and habitat restoration project was completed in 2001, the downtown area had a 50 percent chance of flooding in any given year. The flood control project lowered the chance of flood down to 10 percent in any given year (a ten-year flood), but the improvements could not provide greater protection because of surrounding development.

The city estimates that the original beaver dam increased the chance of flooding to about a six- or seven-year flood event. In early 2008, to reduce the flood danger, the city lowered the dam height and installed a “beaver deceiver,” which is a fancy way of saying a pond leveling device, to reduce the impoundment behind the dam. City engineers also installed a series of cables through the dam that would enable them to haul it out quickly if flooding were imminent.

Meanwhile the beavers have made themselves comfortable. The original pair raised two yearlings in 2007 and produced a second litter in spring 2008. They also constructed a second dam downstream from the first.

In late 2007 the city asked a subcommittee of city council members and concerned citizens to evaluate the city’s options. Although by no means unanimous, the subcommittee report submitted in April 2008 suggested several measures that could reduce the flood potential and allow the beavers, and their dams, to remain. The city is currently evaluating these measures for price and feasibility. However, some residents of Martinez still would like to see the beavers relocated. The California Department of Fish and Game has authorized the relocation of the beavers, if that’s the selected alternative, and a Native American tribe has agreed to accept the animals. Relocation is an unusual step for the state, since they typically exterminate beavers found to be a nuisance—but the popularity of these beavers makes that an impolitic solution. It’s unlikely the city will make any decisions until September at the earliest.

While the City of Martinez is pondering its next move, if any, you can get good views of the beavers during mild summer evenings. They are most active starting an hour or two before dusk. Their lodge is visible on the eastern creek bank just below Escobar Street, the primary dam is between Escobar and Marina Vista Avenue, and the secondary dam is downstream of Marina Vista. You may also see evidence of tooth marks on trees near the creek banks and evidence of past flooding on the neighboring buildings.

Supporters of keeping the beavers in Martinez hope to use funds from sales of a children’s book titled “The Comeback Kids, The Martinez Beavers” to pay for revegetation along the creek’s banks, and to develop an on-site interpretive program.

For more about the beavers, go to www.martinezbeavers.org.

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