Sandoval County Hits a Gusher

John Fleck knows what floats my boat. He sent me Rosalie Rayburn's story from the Albuquerque Journal (you can get a one-time free pass to read it) about Sandoval County (outside Albuquerque, NM) hitting it big - finding enough ground water in the Rio Puerco basin to supply a city of 300,000 for 100 years. All they wanted was about 12,000 acre-feet per year. They got more than they bargained for, after investing $6M.

Last August, also prompted by Fleck, I first posted on this situation.  There are a number of issues here, notably desalination - not cheap, nor easy, as my friend and former colleague Bruce Thomson (here he is discussing anionic manifolds with a Kazakh scientist) pointed out at the International Nonrenewable Ground Water Resources conference last month. It will be tougher and costlier to desalt inland brackish water than it will be to treat sea water.

And there is the problem of the salt extracted from the water - what do you do with it? See my rough calculations in the August 2008 post for an idea of the volume that will be produced.  It is not insignifcant.

And then there is the issue of jurisdiction, or lack thereof.

From the story:

Engineers from Intera, a consulting company hired by the county, pumped about a million gallons of water from one well and measured the effect on water levels and pressure in the other well. 

The 30-day test enabled the Intera engineers to predict that the wells can produce 43,200 acre-feet of water a year, for at least a century. For comparison, the city of Rio Rancho, with more than 75,000 people, currently pumps about 12,000 acre-feet of water annually.

That water was produced from a zone deep enough such that the ground water is non-tributary, or outside the purview of State Engineer John D'Antonio. The Intera folks said that tests have shown that the Sandoval well is unconnected to any nearby water sources and that a fault separates the county's wells from the Rio Grande basin.  A clay-rich layer separates the aquifer from overlying water sources. Hermetically sealed, right?

Note that the Intera test was for 30 days. That duration may not have been long enough to register an effect other wells. And, as I said in my August post, all ground water is eventually tributary, but it may be on a time scale of hundreds, thousands, or millions of years.

D'Antonio can take some solace in the fact that he will ultimately be getting a "new" source of water. The pumped water will be discharged at the surface, where it will find its way into the shallower aquifers and/or the Rio Puerco/Rio Grande.  So maybe he'll have enough water on hand to satisfy Texas.

The developers must be happy - 100 more years of growth! Awesome!

"You Americans have the clock. We Tanzanians have the time." -- Tanzanian man

Comments

[Michael]

Hi, Joe.

Thanks for your astute observations.

I am guessing that it should have read "about a million gallons per day" (c. 700 gpm) and that the annual production refers to the entire aquifer, not just the single well. I don't know of any water wells (or any two) that produce 27,000 gpm!

[Joe Becker]

OK, let's see if I got this right. Engineers from Intera made a 30-day pumping test, producing "about a million gallons." That's a pumping rate of about 23 gpm. From this test they predict an annual, safe production of 43,200 acre feet. That's a production rate 26,780 gpm! I wonder how close their closest observation well was that didn't see any effect of this 23-gpm test. (Thank you to my colleague, Jim Hay, for pointing this out to me.)