"I started getting lots of calls from concerned residents," West Sacramento's Urban Forest Manager Dena Kirtley told KOVR-TV, Sacramento, in a report published Wednesday.
He said about six beavers have been trapped so far but many more are roaming the neighborhood, tearing down trees.
"They can weigh upwards of 70 pounds and some of them, by the damage on the trees, were a good 4-feet tall," Kirtley said.
"It was on a massive scale," he said of the tree destruction. "I think there were about 10 to 12 trees that were felled."
KOVR said most of the damage so far was confined to public property.