Chlorinating Water Tanks
By Eleanor Blazer
       "I'd like my water with a lemon slice, please."

       I looked at Kruzer and told him, "No, we're not doing that any more."

      Under protest he went off to chase Sox.

      Last week we had a 3,500 gallon water storage tank installed.  The tank will give us piece of mind during the frequent droughts in south Texas.  If the well goes dry we'll have time to find water, have it hauled in and the tank refilled.

      Under normal conditions the well will keep the tank filled, which then feeds the house, barn and pastures.  But before we could use water from the new tank it had to be chlorinated.  The interior of the tank may have been dirty from the manufacturing process. 

      The contractor put two cups of regular household bleach in the tank.  Within hours the horses were refusing to drink - not good during record setting heat. 

      Luckily I had emergency water in the horse trailer tank. I also called Sport's "mother" and she brought some water.  But the emergency water was not going to last long and Karla wouldn't be able to haul enough water for seven horses.

      The amount of chlorine in the tank was not enough to cause long term health problems…the horses just didn't like the smell or taste.  The Environmental Protection Agency has determined the upper level of chlorine in drinking water at which no adverse health effects are likely to occur is 4 parts per million (ppm).  (I like their use of "likely".)  I doubt if anything would drink the water at that level of chlorine anyway.

      The EPA does not consider stomach upset or temporary irritation of the mucous membrane as "adverse".  I guess it depends if it's them or us!

      I did some math and determined the ppm level in our tank was around 1.4.  Would this amount even do anything beneficial?

      It turns out the giardia protozoa, which causes diarrhea, can be inactivated by chlorine at a level of one part per million 45 minutes after being added. 

     An interesting side note - the chlorine level recommended for swimming pools is between two and three parts per million.  A test kit for determining chlorine levels in swimming pools is handy for checking levels in drinking water.

      If you think the water source is contaminated with microorganisms, organic or inorganic minerals; contact your health department.

      The American Red Cross recommends boiling a gallon of contaminated water for a full minute, cooling it for 30 minutes and then treating it with 16 drops of 5.25% - 6% non-scented chlorine bleach (eight drops per 2-liter bottle).  I conducted an experiment and tested this concentration with a pool test kit.  The chlorine level was three (3) parts per million.  Pretty strong!

      But all this interesting information was not getting the horses to drink! 

      "You can lead a horse to water, but can't make him drink"…especially if there is chlorine in it!

      I discovered that letting water sit uncovered for several hours allowed the chlorine to leach out.  Pouring water back and forth also helps dissipate the chlorine.

      Why do restaurants put a slice of lemon in your class of water?

       It's to kill the chlorine taste!  The acid in the lemon helps dissipate the chlorine and masks the taste and smell. 

       So Don made a quick trip to the store for lemons.  I filled water buckets and set them out in the sun.  While I waited, I poured water from one bucket to another.

      After washing and slicing the lemons we found several of the horses didn't care for lemons either, but with some experimentation and sugar they were able to drink it.

      Within 48 hours the chlorinated water in the tank became diluted and lemons were no longer required - much to Kruzer's dismay.

      Please don't tell him there is flavored water available!




    * For information about how to care for horses take the online course "Stable Management" and "Nutrition For Maximum Performance" taught by Eleanor Blazer. Earn certification or work toward a Bachelor of Science degree in equine studies.

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