Borrego Sun - Since 1949

Borrego Springs - Water Woes

 

Last updated 2/1/2016 at 4:33am

In the "good old Borrego days," you could dig a hole eight feet deep and find water just about anywhere. But those days are long gone. Borrego Valley averages between 5-6 inches of rainfall per year over a surface area of 121 square miles (9.3 million acres). We also get runoff from the major streams in the mountains, and some from underground sources. But let's use only the lower figure of five inches of rainfall per year to do a little simple math.

In the accompanying graphic, the circle is 10 miles in diameter and encloses 50,240 acres of land. If we could somehow manage to capture the entire five inches of rain every year falling within this circle, we'd have about 21,000 acre-feet of fresh water. That's more than enough to cover all of our current agricultural, golf course, and municipal water needs, currently just below 20,000 acre-feet per year. So, who is allowing all that water to go to waste?! Borrego Water District General Manager Jerry Rowling?! Okay, that was admittedly a trick question, and I think by now Jerry understands my sense of humor in regards to unfairly assigning blame whenever possible to the nearest civil servant.

While the entire Borrego Valley is averaging almost four million acre-feet of water per year from five inches of rainfall, remember we live in a desert. Much of that rainfall evaporates into the dry air after making its way down towards and ultimately settling in the Borrego Sink area. Some water sinks into the earth, and some is taken up by plants and trees. But hardly any rainfall makes it down to our water table in the upper aquifer, now averaging 125 feet below the surface. Most of our aquifer recharge comes from stream flow out of the mountains, plus a little from underground sources. The total "recharge" from all sources is less than 6,000 acre-feet per year, leaving us with an annual 14,000 acre-foot water over-draft.

But what about all the water below the Upper Aquifer? It's plentiful, for sure, but also much deeper. The good news is that we've got about 45 years at current levels of extraction to solve the problem; the bad news is that we have only 45 years to completely solve the problem.

The soils are tight and the volume of water easily extracted drops off to almost nothing at 250 feet below the surface and into the Middle Aquifer. And what little volume there is down at the Middle and Lower Aquifers is very low in quality, sometimes officially designated as non-potable due to dissolved solids and chemicals. Therefore, it requires much bigger and/or more numerous pumps to extract the same volume of water, and such large-volume wells and pumps are also very expensive to install. Not to mention the cost of a water treatment/filtration plant. Like our first traffic signal, we surely don't want that! Let me summarize by saying that if we don't change our ways of using potable groundwater, at some point it becomes more economical to get our fresh water by purchasing the contents of a daily convoy of Sparklett's water trucks.

So next time it rains, enjoy it, but don't count on that beloved water making its way to your faucet.

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