Saturday, August 25, 2012

Drill a well instead of using city water?

Over the years, it has been my understanding that well water could not be used by most district club operations inside the 270 corridor due to its high salt content.  Brian Kohnen, a member at our club did some investigating and got an official version of that story from DNR in the letter below.  Also, even if the water was in good condition to use for turf, one of the things I had forgotten was that the volume of water that can be received from drilling a well is way below what is necessary for us to recharge our system daily.  The output in our area from a well is under 25 gallons per minute 36,000 gallons a day.(36K gallons is nothing to sneeze at and would be helpful but the water is not usable because of the high salt content).  We are in need of 10 times that amount during our heaviest usage periods during the summer.  Wells can run between $ 15-20,000 to drill.

Mr. Kohnen,

The location you provided was not quite as accurate as it needed to be (usually three or more digits after the decimal place are helpful).  However, it was close enough that along with the two logs you referred to I was able to get a good general location.  It appears the golf course you are interested in would be either the Glen Echo or Normandy course (?).  I looked at the geology across the general area of those two golf courses, and the information below is a summary.

There are major issues with getting a well to the desired yield in this general area.  Unfortunately even with 150 acres to utilize, the problems extend well beyond that distance.  Based on all the data available, I would have to say that the chance of constructing a well capable of producing over 200 gpm of useable water is extremely poor.  We had discussed the option of multiple wells feeding into a reservoir, but that may not be cost effective given the low yield of the wells that produce useable water in this general area.  That is something I suggest you discuss with your well drilling contractor and course manager.

This area has a very low yield in the bedrock between ground surface to approximately 400 to 500 feet (depending on ground surface elevation).  The yields produced generally ranges from 1 to 10 gallons per minute (gpm).   While there is considerably higher yield available in the bedrock below this depth, the water quality degrades very quickly.  There have been very few wells drilled in this area over the years, due to the conditions mentioned above.  I have looked at the water analysis from the wells of record closest to your location.

The well closest to your location was drilled to a total depth of 460 feet.  The water quality analysis done reported the following levels (in parts per million, ppm): Total Dissolved Solids (TDS) 532, Chlorides 27, Sodium 148, iron 2.09.  While the iron level could be problematic, overall the water would seem to be of a useable quality.  The main problem is that the well yield was estimated at 1 gpm.  None of the surrounding wells I researched that produced from this ‘zone’ were in excess of 7 gpm.

All the data from deeper wells indicates the water quality degrades very quickly below that depth.  A well to the west of your location had unusable water (TDS over 6,000, Chlorides over 3,000) by 500 feet.    

Data from two wells approximately 1.5 miles south of this location (total depths 825 and 850 feet) indicated the yield was still less than 75 gpm.  At this depth the TDS was over 5,300, the Chloride levels were over 2,500, and the Sodium levels were in excess of 1,500.  

I’m not sure what quality of water you could still find useable for your purpose (greens irrigation).  You may wish to consult with the county extension office in your area or your greens expert as to what levels of mineralization the grass you use can tolerate.

Please see the attached map.  This is the area reviewed, if it is not correct please let me know and I can revise the review area as needed.  I’m sorry there is not better news concerning water quality and quantity in your area, if I can be of any further assistance please feel free to contact me via any of the methods listed below.


Matthew Parker, RG
Division of Geology and Land Survey
Geological Survey Program
Wellhead Protection Section
P.O. Box 250  Rolla, MO 65402
573/368-2317 (fax)

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