Subzero Frost Free Tank

Recently we posted a short video (YouTube link) to the DS Family Farm Facebook page showing how we provide fresh water to the cow herd in subzero weather. Late December 2017 through early January 2018 we had a 17 day stretch with temperatures below freezing (32 degrees Fahrenheit) and many stretches below 0 degrees F (-18 degrees Celsius).  The system worked fine and we finally sold the propane tank heater we were keeping around for backup.

The secret is to keep the water surface protected from the WIND!  Since the video generated some questions on how the system exactly works, below is our “How To install a Subzero Frost Free Tank”:

Step 1:  Start with a heavy-duty tire from your local shop.  A few years ago we were able to get a used tire for two-dozen donuts!  The tire shop workers were glad to see us coming.

Step 2:  Place and level tank in pasture.  We place the tire tanks on a ridge, in a fence line dividing two pastures.  We also drill a hole near the bottom of the tire and insert a pipe with a valve.  From the valve we run poly pipe over the ground and gravity flow water to portable tanks throughout the pasture (not during winter).

Step 3:  Bring water source (trench in pipeline) up through the bottom of the tank and also add overflow outlet tube/pipe if you like.  Next add concrete to plug the bottom of the tire hole to create a “tire tank” that holds water.

Step 4:  The tank pictured below serves as our freeze proof tank (see diagram at end of this blog post).  The pump only runs when we have sunshine!  The photo below was taken during a long cloudy stretch of weather a few years ago.  A series of 12 volt batteries connected to the controller will run the pump without solar power.  Just once or twice a year we may run out of stored water before the sun shine’s again.  (Solar panel in background of photo below).

Step 5:  During winter, add a cover with flaps and cattle simply raise the flap to reach water.  In southeast Nebraska we are blessed with consistent sunshine during winter.  Even on cloudy winter days the solar panel will usually generate enough power to pump water and keep the tank recharged with fresh warm water.  If the air temperature reaches near or above 32 degrees F, this system works without any problems.  If temperatures are well below freezing, a layer of ice may form overnight on the water surface.  Cattle usually break the ice on their own and drink but the float switch may be frozen in the ice layer above the water surface.  We have to break the small layer of ice and allow the float switch to fall to the “ON” position for the pump to run.

Overview of entire system:

One last note on our system:

We actually run two tanks from this single well/pump setup.  A valve near the well (below the frost line) allows us to direct water to either tank pipeline.  With a float switch in each tank, we inserted a three-way switch to the controller.

1. With the controller switch in the top position, the float switch at the top tank controls the pump.
2. With the controller switch in the bottom position, the float switch at the bottom tank controls the pump.
3. With the controller switch in the middle position, neither float switch controls the pump!  Pump is always “ON”.

What is the advantage of being able to switch the pump to always “ON”?

• Answers:
  • In very cold weather, with the switch always “ON”, when the sun shine’s, the pump is running water.
  • Any extra water just runs into a pond at the “overflow tube” outlet (to daylight on diagram).
  • If a layer of ice forms overnight, the new fresh “warm” water will thaw the ice layer.
  • This gives us one more option to make sure the cattle always have access to fresh water.

In summary, protect the water surface from the wind and recharge fresh (warm) water daily.  Do your research, information from Canada is very helpful.  We also like these ideas:

• Add a thermal “heat tube” under the tank
  • Based on our experience, not necessary if you have adequate recharge in our environment.
• Frost free “nose pump”
  • Yes, cattle pump water when they need it with their nose!