SAN BERNARDINO COUNTY, California – Set against the backdrop of the San Bernardino Mountains, the Mojave River Dam and its surrounding area is known for many things – its beautiful landscape filled with Joshua trees, desert flora and fauna, and the national scenic Pacific Crest Trail, an area frequented by hikers and equestrian riders.
It also has become an area recreated illegally by off-road vehicle enthusiasts, an activity prohibited in and around the dam because the area is designated as a critical habitat for endangered species.
Park rangers and engineers with the U.S. Army Corps of Engineers Los Angeles District traveled to the dam March 2 to begin the initial planning stages of installing a security and restoration barrier on the south side of the dam to protect endangered species and their habitats.
“The area is designated a critical habitat for the arroyo toad, but there are a couple of other critical habitat species that we know could live in that type of habitat,” said LA District Park Ranger Henry Csaposs. “It’s an oasis, basically. It’s the only place in the desert for miles around that you can find water, and that means there’s all sorts of unique plants, animals and wildlife that come out here. And it’s really an important spot for humans, too. It’s part of the Pacific Crest Trail, which is a national scenic trail and a really valuable resource.”
Other known species that call the area home include the Southwestern Willow Flycatcher and the least Bell’s vireo, among many others.
During the site visit, the team – which consisted of park rangers, engineers and a biologist – surveyed different access points around the dam and discussed what barriers would be most suitable for each location to keep off-road vehicles out of the critical habitat areas.
Some of the barrier methods discussed included pipe and cable fencing around the perimeter, with boulders, K-rails and perhaps other sturdy barriers positioned at key access points.
“We definitely don’t want to prevent hikers or people on horses from having access to the trails,” said LA District Park Ranger Connie Chan Le. “Our main focus is folks, who are illegally trespassing on OHVs, bikes, ATVs and any motorized vehicle, that’s really not supposed to be in this critical habitat area.”
When it comes to the arroyo toad, the species needs loose gravel and sand to breed, Chan Le said. When off-road vehicles compact the area, it hinders breeding success for the toad, which is already an endangered species.
Other issues from people driving off-road vehicles in the area, include vehicle accidents and vandalism, Csaposs added.
“We’ve had fatalities and serious vandalism caused to the dam – to the tune of millions of dollars in damage,” he said. “And the habitat – it’s really been impacted by the people driving over it. It causes erosion, it kills the plants, and it makes it so the toads and other animals don’t have a place to live.”
Right now, the team is estimating a three-year time frame for construction and installation of the barriers.
“We are just in the beginning stages,” Chan Le said. “We are trying to get a picture of what our barrier plan might be. We have been in constant communication with our partners, so there might be a possibility of working with them for some of the barriers.”
Funding for the additional barriers at the dam will come from the Operations and Maintenance fiscal year 2022 work plan, with funds received through the Infrastructure and Investments Job Act.
In the interim, the park rangers want to remind off-road vehicle recreationists that not far from the dam, a huge set of legal trail systems, managed by the U.S. Forest Service and the nonprofit Southern California Mountains Foundation, is available to them.
“They do have a huge system of legal trail systems – for the single riders, all the way up to families,” Chan Le said. “They are just beyond our property, and they provide maps, kiosks, a website, and, of course, their own staff to provide information to the public on where they can legally recreate … There are plenty of other opportunities that are safe, legal and off the water.”
ABOUT THE MOJAVE RIVER DAM
Built in 1971, the Mojave River Dam was designed and constructed to reduce flood risk for more than 16,000 people and $1.5 billion in property.
The LA District owns and operates 17 dams across Southern California, Arizona and Nevada that reduce the risk of flooding for millions of people and billions of dollars in property. The dams are reviewed periodically and rated according to the age and condition of the dam and potential consequences.
The LA District’s dams range from low to very high urgency of action. Routine operation, maintenance and inspection activities are performed to ensure the dams perform as designed.
Under the Infrastructure and Investments Job Act, or IIJA, about $1.8 million is slated to address repairs at the Mojave River Dam.
This comes on the heels of a Jan. 19 announcement by the U.S. Army that included a list of Civil Works studies, projects and programs the Corps of Engineers will implement nationwide in Fiscal Year 2022 with $22.81 billion in supplemental funding provided in two recently enacted laws — the IIJA and the 2022 Disaster Relief Supplemental Appropriations Act.