Rural Water Systems – Tanks

If your water system is supplied by a well, it must have at least one pressure tank.  The tank has two chambers.  The upper section is filled with compressed air, the lower section holds water from the well.  The water chamber usually has a rubber liner that provides a flexible diaphragm between the two chambers (like a balloon).

As water flows into the lower chamber, the diaphragm expands and pushes against the air, which is compressed in the upper chamber.  The air pushes back against the diaphragm.

This maintains system pressure.

When you fill water buckets for your horses, air in the upper chamber pushes water out of the tank and into your system.  Check valves in the discharge line from the pump make sure water doesn’t go back into the well.

When the system pressure drops below a pre-set point (determined by the pressure switch), the pump cuts in and refills the tank.

Pressure tanks are usually installed on the ‘raw’ side of the system, that is, upstream of the treatment equipment.  More on that in a subsequent post.

You probably want a pressure tank that holds at least 20 gallons of water.  The more capacity you have, the fewer on/off cycles for the pump, which extends its life.  You can install pressure tanks in parallel for more storage.  A horse ranch should have at least 40 to 60 gallons of water under pressure.  Install a valve at each tank so it can be taken off-line without shutting the system down.

Vendors such as this one offer a range of pressure tanks and parts.

Tanks must be emptied of water before setting the air pressure in the upper chamber, which should be two psi below the ‘low’ setpoint of the pressure switch.  If your switch turns the pump on at 40 psi water pressure, set the pressure in the upper chamber to 38 psi.

Pressure tanks often have valve stems on top similar to those on the tires of your car.  You can use the same tool to check the air pressure in your tank(s).

If you live on a ranch, you may have a portable compressor for keeping the tires of your tractor properly inflated.  You can use the same machine to service your tank(s).

In some areas, large non-pressurized tanks may also be required to provide water for fire protection.  For example, a 5000 gallon poly tank with roof, or two 2500 gallon poly tanks in parallel.  Water in these tanks might sit there for weeks or months.

Bulk tanks don’t store water under pressure.  You’ll need a booster pump to supply the firewater system.

If these tanks provide water for your potable system, the booster pump would send water over to the treatment equipment and then out to your horses.

In both cases, the tanks would hold untreated (raw) water from your well, taken from a point downstream of the pressure tanks.

Your pump may run for several hours when filling a bulk tank.  Make sure you’re not drawing water out of the well faster than it flows in!


ISPMB Update

Go to this FB page for the latest on the rescue, now in its final stages.  A home is needed for twenty aged and/or blind stallions.

The story of the ISPMB rescue appears on a related FB page.

Three cheers to Elaine Nash and her team at Fleet of Angels, along with Palomino and Matt Armstrong of Chilly Pepper Miracle Mustang!

The ISPMB sanctuary included horses from White Sands NM, Gila Bend AZ, Virginia Range NV and Sheldon National Wildlife Refuge NV.

RFP for VR Horses: Stakeholder Involvement Required

According to the motion approved by the Nevada Board of Agriculture on 12/12/17, ownership of the Virginia Range horses could be transferred to ____________.

  1. A faraway animal advocacy group that specializes in dogs and cats.
  2. A non-profit group sponsored by a cattle rancher’s association.
  3. A network of veterinarians with ties to the pharmaceutical industry.
  4. An environmental group that sees great potential for wind and solar.
  5. A private group that puts animal rights ahead of property rights.

Answer: None of the above.  The Department of Agriculture probably wouldn’t accept any of those choices.  Neither would the people in and around the Virginia Range.

Why?  No stakeholder involvement.

Consider this approach: Privately owned but publicly held.

The group that owns the horses should be related to those who own the land on which the horses roam.  Keep decision-making authority close to the people affected.

Power over the horses should not be concentrated in the hands of a few.  A non-profit corporation directed by its members (e.g., land owners) might work.  This would be the legal entity to which the horses are transferred.  The land owners could provide ‘seed money’ for the corporation.

The corporation would also accept support from other interested parties, such as monetary donations, grants, donations of equipment/materials/tools, donations of services, people who volunteer their time.

Bylaws would specify what the corporation does and does not do, procedures for meetings, how to make decisions, who has voting rights, etc.

Policies, programs and practices for managing the horses would be subject to member approval.

Some folks are upset with the Board’s decision, understandably.  But we have to face the situation as it is and be creative.  These are Annie’s horses.  The Virginia Range is ground zero for the wild horse preservation movement.

You can still spend a lot of time with those guys (the VR horses).  There is a lot of work to do and the clock is ticking.  The RFP will be posted in three or four weeks.

Rural Water Systems – Pumps

Now that you found water on your property, you’ll have to bring it to the surface.

If the water level is 30 feet down or less you can install a pump at grade.  This would also apply to water drafted out of a spring or pond.  Keep in mind that surface water is more susceptible to contamination than ground water.

A surface-mounted pump should be self-priming, which means it can draw water from the source even if the suction line is empty.

If the water level is below 30 feet, the pump will have to go down hole.  It has to do three things:

  • Lift water to the surface
  • Push it into the pressure tank(s)
  • Overcome friction in the discharge piping

Suppose you drilled your well to 480 feet.  You hit water at 420 feet and the static water level is at 360 feet.

You don’t want to install the pump at the bottom of the well.  Leave some room for accumulation of silt and sediment.  At least 20 feet.  That puts the pump at 460 feet.  Although the water level is 100 feet higher, the worst case is when you pull water too fast and drop the level down to the pump.

This brings up the concept of recharge rate.  Water enters the well through perforations in the casing.  You don’t want to draw water out faster than it flows in.  At least not for long.  Running a pump dry will destroy it.

Your driller can perform a test to determine the recharge rate.

The system pressure is controlled by a switch that turns the pump on and off automatically.  Typical pressure range is 40 to 60 pounds per square inch (psi).  On at 40, off at 60.  Greatest pressure is therefore 60 psi.  As you use water, the pressure in the system drops until the pump kicks in and refills the tanks.

The amount to allow for pipe friction depends on the water flow rate, pipe size, and length of discharge line (depth of pump plus distance from well to pressure tanks).  If the line is properly sized, this number will be small.  Start with 5 psi.

Summary of conditions for this example:

  • 460 foot lift
  • 60 psi to get into tanks
  • 5 psi pressure loss due to friction

Pumps curves are based on feet not psi.  To convert, multiply psi by 2.3 to get feet.

Total head = 460 + (60 × 2.3) + (5 × 2.3) = 610 feet

Round to 600 feet to keep things simple.  Here are curves for Goulds series 7GS pumps.

7GS Curves

Start on the y-axis at 600 feet and move to the right.  When you hit a curve read down to the x-axis.  A 7GS15 pump will give you about 5 gpm.  A 7GS20 will give you 8.5 gpm.  A flow rate of 5 to 10 gpm should be adequate for you and your horses.  Boarding facilities and farms require something larger.

Comment on NDA Plan for VR Horses

If ownership of the Virginia Range horses passes from the Nevada Department of Agriculture to a privately owned animal advocacy group, as proposed by the Board of Agriculture on 12/12/17, you will have animals belonging to one party grazing on land owned by another.

Can private party A (who owns horses) compel private party B (who owns land) to accept A’s horses for grazing?

If A can place his property on B’s land without B’s consent, could A also place cattle and sheep on B’s land?  Equipment and supplies?

How will the concept of fence out / open range work in this environment?

See NRS 568.300.  The horses will be considered livestock when placed into the hands of the advocacy group.