Well Water Cisterns

Through the years, we have perfected the design and installation of our cisterns. There are some things that take place during the assembly, the excavation, and then the installation that we consider to be proprietary, and that are not explained in the following information.

The average on-site installation time for a cistern usually takes less than eight to ten hours. We provide a fully stocked service truck, the necessary trained personnel, additional pipe, conduit and wire, frost free hydrants, and other materials for connecting to the rest of your water system.

Either we joint venture with professional excavators or we do the excavation ourselves. A joint venture means that we work with an excavator who contacts you with his rates, you contract with him, and then you pay him directly – although the excavator works at our direction while on site. When we are extremely busy or if you already have a qualified excavator working at your job site, the joint venture arrangement sometimes saves time and / or money.

The downside to this arraignment is that if your excavator is not qualified and you don’t know it – yet – we are going to contact you in writing over whatever work didn’t take place properly – or we are going to shut down the job. We have lost our sense of tolerance for working with unqualified excavators over the years. We have ‘held the bag’ for poor quality work from excavators who have over-dug the hole, who didn’t provide the right drainage slopes, who didn’t tighten up the ground properly around our plastic equipment, who are not in control of their equipment – and on and on. This is why we do most of our own excavation, now.

Underground cisterns are used when:

  1. Your well does not produce enough water for surge periods. A surge period would be: showering in the morning, then running a load of laundry and also running the dishwasher before leaving for work.
  2. You have a source of water that is intermittent. Perhaps your incoming subdivision water or well water is unreliable; or you have to have water hauled in.
  3. Your incoming water does not give you enough pressure or maybe the pressure fluctuates due to other water users on the system.
  4. You need to treat the water. Water needs to have ‘contact time’ with chlorine or ozone for sterilization. Contact time is also needed for the Iron or hydrogen sulfide to ‘grow’ or oxidize so that filtration can remove it.

We supply pre-built cisterns that have the following features:

  1. The submersible pump lies horizontally in the bottom of the cistern which allows all but the bottom 5″ of water to be used in the cistern. The pipe from the pump is connected to a union or pitless accessible from the manhole. That way the pump can be replaced while the cistern is full of water.
  2. Inside the cistern, we build a unique manifold assembly that connects to the union from the pump; the electric float switches (or the float valve) is mounted to it and the water line feeding the cistern is part of the manifold. You are able to see the incoming water being discharged into every one of our cisterns.
  3. All of the water and electrical connections are made at one end of the cistern. We use only the high quality Spears stainless steel jacketed bulkhead fittings that won’t crack or break at the waterline connections. The waterline connections are directly below the PVC electrical junction box which is mounted on the manhole riser.
  4. Every cistern comes with the middle float switch internally installed that will activate a low water alarm. Our standard alarm is a 115 volt, ½” diameter red signal light and a cover plate for a standard 2″ x 4″ ‘handi box’ that is usually mounted in the house.
  5. A manhole riser is attached to the cistern with stainless steel screws. This allows full access to the equipment in the cistern, while being able to bury the top of the cistern one foot deep.
  6. We install one of our top quality, professional grade submersible pumps (see our pumps section) that always has a built in check valve, and is installed in a shroud for proper motor cooling. Our standard size of pump is the ½ hp – 10 GPM  pump that delivers 12.4 GPM at 40 PSI and 10.4 gallons per minute at 60 PSI, when the total lift is 20′ from the bottom of the cistern to the highest usage point, usually your shower head. This size pump usually produces plenty of water pressure and volume for up to a three bathroom house.
  7. The float switches are connected to a PVC pipe that is joined to the manifold assembly with ‘snap tees’. This allows easy removal of the switches for adjustment or replacement.
  8. We use only top quality, full size Spears PVC fittings, Schedule 80 PVC pipe, poly pipe rated for at least 200 PSI, brass fittings, and stainless steel fasteners. No galvanized materials are ever used.
  9. A 4″ fill cap and ¾” screened vent is mounted on the lid of the manhole riser.

Cistern Options:

  1. A ¾ hp-15 GPM pump can be installed for additional volume:  This pump is a good choice if you have a guest house or if you have rotating sprinklers.  This pump delivers 18.6 GPM at 40 PSI and 15 GPM at 60 PSI, when the pump has a total lift of 20′ from the bottom of the cistern to the highest usage point, usually your shower head.
  2. A ‘constant pressure’, variable speed, high volume pump: Applications include; household use with larger scale exterior irrigation, multiple houses or small subdivisions, or small RV parks.
    1. This pump has a sensor that is placed at the small pressure tank. It generally keeps the pressure within 2 PSI at the sensor. The sensor sends a signal to the controller and the control box sends the amount of electricity to the pump to spin the pump to deliver whatever amount of water is necessary to keep the pressure at the sensor within 2 PSI. The pump ‘loafs’ most of the time, causing little wear to the pump and minimizing the cost of electricity.
    2. The controller takes 230 volt, single-phase electricity, and makes three-phase electricity that the pump motor uses. The pump, motor, controller, and sensor, are all made by Franklin Electric for a matched system. The pump sizes can vary from 15 GPM up to 100 GPM, depending upon what your application is.
    3. When we build this pump into our cisterns, the size of the internal manifold piping is increased to the proper size to handle the additional flow.
  3. Extra manhole risers are used when you want to install the cistern deeper into the ground, (usually for freezing purposes) or if you want a riser on the opposite end of the cistern for additional access.  The risers are supplied with 12 stainless steel screws and a tube of Lexal for a water tight seal to either the cistern or the previous riser.
  4. The combination alarm has an internal 80 decibel horn with a light. This is an exterior rated electrical box that can be mounted outside. When the water is low, the horn sounds, and the light comes on. You press the button on the box that shuts off the horn, and the light remains on until the water level increases.
  5. We build a unique cross-over check-valve assembly that allows the water from the subdivision to pressurize the water system when the water pressure from the subdivision is high. When the subdivision water pressure begins to drop, only then will the pump in the cistern turn on and bring the pressure to the house to the normal regular pressure. This option reduces the wear and cost of operating your cistern pump while the subdivision water pressure is up.

This cistern has the Constant Pressure system built in to it.

Lifting . . . Lifting . . . Lifting . . .

Two Cisterns & a Vault - an underground Pump House.

Lots of special fittings and clamps - you don't buy this stuff at the hardware store!

Every year we get people from hundreds of miles away driving to our shop here in Pagosa and purchasing our pre-built cisterns. This is another part of the water systems business we excel at, and we enjoy being out front with the best cisterns, pre-built for ease of use, and installed without compromise.


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