MWD Scurries to Build Walls That Save Rats

There have been several famous walls in history: the Great Wall of China, the Berlin Wall, the Wailing Wall.

Now comes the $360,000 K-Rat Wall in Riverside. It gets its name from the Stephens’ kangaroo rat--a nocturnal, burrow-dwelling, chipmunk-like rodent that propels itself kangaroo-style on powerful hind legs.

Those powerful legs have gotten the species into powerful trouble. The rats have been wandering onto land belonging to the Metropolitan Water District’s Mills filtration plant--much to the dismay of MWD officials. Because the rat is endangered, the district could face heavy fines if it even inadvertently harms any.

“That’s the problem,” said George Buchanan, 44, area superintendent for MWD at the plant near Lake Skinner. “We’re in the throes of a $140-million expansion project here, new pipelines, large landfills, treatment plants. We have a lot of heavy equipment working on the site.

“If one of our employees kills an endangered Stephens’ kangaroo rat it could mean as much as a year in jail and a $50,000 fine. That’s a lot of money, and no one wants to go to jail.”

Hence, the MWD is building the wall to keep the rats out. Nearing completion, it is 4,500 feet long, 10 inches wide and about two feet high.

The water district plans to build another rat wall, 1.2 miles long, before the end of the year at its Lake Skinner water treatment facility 35 miles south of Riverside.

That 2-foot-high, 2 1/2-foot-deep wall was to cost $450,000, but MWD is redesigning it, hoping to reduce the price to $200,000.

After the walls are completed, the rats will be trapped and moved over the walls and off the MWD properties.

About 25 different species of kangaroo rats live in the deserts of the southwest.

The Stephens’ kangaroo rat is found in western Riverside County and in a few small pockets of southern San Bernardino County and northern San Diego County. But urban development is bringing about its rapid decline.

Michael O’Farrell, 47, a wildlife biologist and one of the few experts on the rodent, estimates that there may be 20,000 to 30,000 of the rats left. They were declared an endangered species in October, 1988.

O’Farrell’s biological consulting firm, based in Las Vegas, has been working under a $500,000 contract to determine whether the rats can be safely trapped and moved to new locations. Since November he has captured about 150 Stephens’ kangaroo rats. All the animals, the scientist reports, appear to be have survived in good health. They are scheduled to be released soon.