Automatic Water Source Switch

[notorioush]

Hello,

We are on a dug well that tends to run dry few times every summer. We are getting a cistern installed as a back up. Is it possible to install a system that the house runs from the well as primary source, and when the pressure or well runs low it automatically switches over to the cistern. When the well recovers it would switch back to the well? if so what would we need in terms of setup of pumps, switches, relays.

Please let me know, any help is appreciated.

Thank You,

 

[Valveman]

When you have a cistern, you need to use the cistern. You don't want water just sitting in the cistern turning green and growing stuff. If you use the cistern regularly, the water will stay fresh. Also, if your only source of water is the dug well, when the well is dry the cistern will be dry also. But you could turn off the well pump and have water trucked into the cistern at that point if needed.

If the well doesn't completely go dry, it might still trickle enough to keep the cistern full.

Dry well protection like the Cycle Sensor for both the well pump and booster pump is important.

 

[Sponsor]

 

[notorioush]

When you have a cistern, you need to use the cistern. You don't want water sitting in the cistern just sitting there turning green and growing stuff. If you use the cistern regularly, the water will stay fresh. Also, if your only source of water is the dug well, when the well is dry the cistern will be dry also. But you could turn off the well pump and have water trucked into the cistern at that point if needed.

If the well doesn't completely go dry, it might still trickle enough to keep the cistern full.

Dry well protection like the Cycle Sensor for both the well pump and booster pump is important.

View attachment 93097

Thanks! However the cistern is underground below the frost line. I don't think it should grow anything here in Ontario, Canada. also the well and cistern are not connected (reason being the when well water gets low it tends to pick up dirt and we dont want that to build up in the cistern). They are individual with individual lines into the house. so essentially we need some sort of automatic transfer between the two depending on the level in the well.

 

[Valveman]

OK. I understand that. You don't want to use any more of the cistern water than necessary because it is already trucked in. Makes sense. We can do that as well. You still need dry well protection like the Cycle Sensor on the well pump. It will shut the well pump down anytime it is starts sucking air. You can have it set for up to 5 hours to try and restart the well pump. If the well is still dry it will run 10 seconds and shut off for another 5 hours.

Then all you do to make the well pump primary and the cistern pump secondary is to stagger the pressure switch settings. Using 40/60 for the well pump and 30/50 for the cistern pump will make the well pump run first and the cistern pump will not come on until needed. When the Cycle Sensor has the well pump shut off and you call for water, the system pressure will drop to 30 PSI and the cistern pump will automatically take over. As soon as there is enough water in the well to let the well pump run, it will build the pressure back up and take over again at 40/60.

However, even underground and in Canada, if that water sits in the cistern for very long you will probably need to add a little chlorine every once in a while.

You can use this drawing, You just don't need the line from the well pump up to the top of the cistern.