TomSeller
Super Member
El Nino looks like a good bet to happen later this year.
Southern CA will likely get a good drenching. I lived in Orange County in the 1990s when we had several EL Nino events. One of them caused the Santa Ana River to nearly top the levees which would have flooded my neighborhood.
However, here in Northern CA it's 50/50 (historically) whether any given El Nino will mean gully washers. Which is bad news for drought alleviation since nearly all of the large reservoirs that capture snow melt and rain runoff are located here. These reservoirs are running dry in a hurry.
Consequently, the agriculture industry in CA has been pumping ground water like there's no tomorrow. That's dramatically lowering the water table in the Great Central Valley and in the North Sacramento Valley. Ground subsidence is a real problem in areas between Bakersfield and Stockton. Causes leaks and breaks in the large and small irrigation canals.
I checked the most recent ground water elevation (GWE) maps that were released last month. At my former ranch in Tehama County the water level in shallow wells (200 feet deep or less) has dropped about 30 feet in the 2004-14 period. In the one year period covering 2013-14, the drop was about 12 feet. My guess is that most of that 30 ft drop has happened in the past four years of severe drought that has caused the orchard growers in my neighborhood to pump groundwater year round to save their trees.
When my well was drilled in May 2005, the water level stood about 55 ft below ground level. In July 2014 my neighbor's well (pump at 90 ft level) went dry. It's about 500 ft away from my well which is 154 feet deep with the pump at the 120 ft level. If the water table continues to drop at 12 ft/year, my pump should become uncovered in 2-3 years. The pump (1.5 hp, 30 gal/min) could be lowered to maybe 135 ft but that could cause sediment in the bottom of the well to be stirred up by the pump. So better filters would have to be installed. That would buy maybe a year of extended service from that well.
After that time a new well would have to be drilled. The existing well has 6" dia steel casing and cost $21/ft to drill in 2005. Total cost of the existing well was $5500. Today that drilling cost here in Northern CA is $50-60/ft. A new well would have to be drilled into a lower strata at 400-500 ft depth. So figure ~ $30,000 for that deep well.
That's one of the reasons I sold the place in Jan 2015 after 10 years of satisfied ownership.
Wow, all that from "One super hot day over the summer, it's climate change"?
Amazing some think what is going on in California is an overnight fluke that will go back to normal the next day.