Local water officials are moving forward with a plan to clear out channels around Plunge Creek that haven’t been used for 50 years.
The goal of the Plunge Creek Conservation Project is twofold: to increase groundwater storage and protect endangered species.
Another goal is to keep the flood-control system working efficiently.
The San Bernardino Valley Water Conservation District board voted on Wednesday, Feb. 14, to approve an environmental document. The comment period closed the day before on the mitigated negative declaration, required by the California Environmental Quality Act (CEQA).
“By restoring some of these abandoned channels and the function of those channels, we’re going to be putting more water in the ground,” Land Resource Manager Jeff Beehler told the board.
The project is part of the Santa Ana River Wash Habitat Conservation Plan. It covers 1.7 miles of Plunge Creek, southwest of where it runs under Greenspot Road near Alta Vista Road in East Highlands Ranch.
The Plunge Creek watershed begins above Greenspot Road in the San Bernardino Mountains. When there is adequate rainfall, it flows for about 10 miles, dropping about 2,500 feet until it reaches the confluence with City Creek.
The California Department of Water Resources will provide $500,000 for the $710,000 project. Conservation District funds will cover the rest.
The San Bernardino County Flood Control District also is a partner in the project and helped with the design.
Two pilot channels from the active channel of Plunge Creek will be excavated through the historic floodplain and back to the active channel, the declaration says.
Heavy construction equipment will be used to dig out an abandoned channel that will flow back into the main creek, Beehler said.
“There will be additional mounds or rock structures put here in the river to direct the flow back into another channel that has not seen the flows in at least 50 years,” said Beehler, pointing to a map displayed for the board.
The project will impact 8 acres temporarily and 5.9 acres permanently. It will involve minimal changes to the channel, he said. Permits were submitted to resource agencies and the Regional Water Quality Control Board and the Department of Fish and Wildlife.
It will add about 13 acres of habitat for San Bernardino kangaroo rat and Santa Ana woolly star, an endangered plant that has light grey-green stems and leaves with bright blue funnel-shaped flowers. It grows to about 3 feet and flowers between May and August, most heavily in June, and fruits from July to mid-October.
It will increase recharge in the area by about 36 percent during a 10-year storm, Beehler said. All of that water will enter the Bunker Hill Basin. A 10-year storm is fairly moderate, but a single storm can produce about 3,000 acre-feet, enough to provide a year’s supply for 2,100 people.
“In wet years, the project has the potential to bring up the level of the basin increasing the amount of water available,” Beehler said. “The Plunge watershed is relatively small and the amount added to the basin is dwarfed by Santa Ana and Mill Creek flows.”
Construction is expected to begin in August and should be complete by September.
“We were not able to move forward with permit applications until there has been a CEQA determination, and that’s what we’re considering here today,” Beehler said.
The board approved the project unanimously.
GROUNDWATER AWARENESS WEEK
The National Groundwater Awareness Council will celebrate Groundwater Awareness Week March 11-17. Its website provides these facts:
* Only 1 percent of the water on Earth is usable, 99 percent of which is groundwater.
* The United States uses 349 billion gallons of fresh water every day.
* Groundwater is 20 to 30 times larger than all U.S. lakes, streams, and rivers combined.
* Groundwater accounts for 33 percent of all the water used by U.S. municipalities.
* 44 percent of the U.S. population depends on groundwater for its drinking water supply.
* More than 13.2 million households have their own well, representing 34 million people.
* 53.5 billion gallons of groundwater are used for agricultural irrigation each day. In 1990, that number was 2.2 billion.
* The largest U.S. aquifer is Ogallala, underlying 250,000 square miles stretching from Texas to South Dakota. Scientists estimate it could take 6,000 years to naturally refill the aquifer if it were ever fully depleted.
* California pumps 10.7 billion gallons of groundwater each day, a third more than the second-highest state, Texas.
* Groundwater is the world’s most extracted raw material with withdrawal rates in the estimated range of 259 trillion gallons per year.