San Diego County’s Evolving Water Supply
Thursday, December 20, 2012
SAN DIEGO The Olivenhain Water District hopes to know soon whether a three month drilling project hits pay dirt. The agency is spending just over $400,000 to see if there's a groundwater reservoir that the district can turn into drinking water. The drill is easy to spot, for those looking. An American flag waves at the top of the forty foot tall rig.
Geologists and San Diego water managers are hoping to tap into an ancient underground river that might run under the ecologically delicate San Elijo Lagoon.
Danskin is using this drill to find out if the rocks below are hiding a vein of water worth tapping. Danskin sweeps his arm across the high ground to the east as he talks about the potential. He says this has been the edge of the North American continent for 60 million years.
"And the rain that falls in the mountains, slowly filter into that sediment and rock, and moves very slowly over a period of tens of thousands of years to eventually empty into the ocean, flowing beneath us and emptying into the ocean," says Danskin.
The crew here used a drill to bore a 1,200 foot deep hole into the narrow strip of land between the interstate and lagoon. They are currently pumping air into the well, hoping to force water up.
"As the air is injected, it bubbles up, somewhat like a geyser and you'll see the hose dancing and moving as the air bubbles flush out, sporadically," Danskin says as he points at the jumping water line.
Next to the pump sits a filter unit that about the size of an ocean going shipping container. Steam rises from the water as it squirts and splashes into what's essentially a large mechanical pan. A warm blanket of air rises from the water.
"Part of this heat is that we're pumping from about a thousand feet of depth," says Danskin.
Right now the slurry is a mixture of sand, stone and water. But once the well hole is cleaned out, Kimberly Thorner hopes it will be mostly water. She's the general manger of the Olivenhain Water District. San Diego's last drought pushed the water agency to start seeking out local water.
"As we started looking at the data, one of the interesting things that we found was, in this lagoon, in San Elijo Lagoon in the early 1900's, the Cardiff Oil Company dropped a well 800 feet looking for oil and they found water," says Thorner.
Water, not oil, is the liquid that packs an economic punch in San Diego these days. If crews do tap an underwater aquifer, the water district is poised to invest $20 million in a plant that would purify the brackish soup. That's why the drilling project holds so much hope.
"It's to find out what's down there. What the potential is, so we can kinda get an idea if this is the area or do we need to look elsewhere," says Thorner.
A successful local drilling project could allow the agency to pump 1.5 million gallons of water a day, from the ground.
This project is a small but important piece of the region's water supply portfolio according to Ken Weinberg, director of Water Resources for the San Diego County Water Authority.
"We're limited in what we can do here. Geologically, we don't have big groundwater basins. But where we can recover groundwater, that's important," says Weinberg.
Local supplies already meet 16 to 17 percent of demand in San Diego County, and that's sharply higher than 5 percent of locally produced water back in 1990.
"Seawater desalination, that's going to raise it another 7 percent," says Weinberg. "And we've got more recycling under development, more groundwater projects, we're going to have a pretty healthy part of our water supply coming from local sources here in San Diego County."
The soaring price of imported water is part of what's making these local projects so attractive, according to Weinberg, who goes on to say the price of water has only gone up in recent years and there is no indication it will retreat anytime soon.
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