Add Water Storage tank before water heater

Hello everyone,

I'd like to add a 300 gallon water storage tank in line before my hot water heater. This is to have emergency water storage available. Could I just run the cold water input from the hot water heater into the top of the tank and then run a new pipe from the bottom of the storage tank into the water heater? Would the pressure be enough, or would I need to add a pump or something?

Thanks for any help!

I would imagine this would depend on whether the storage tank could withstand the constant water pressure from your water source. I had an old steel tank which I had planned on utilizing similar as you, but scrapped the idea because of the space necessary to store the tank.

yes, sounds like it will work without a pump.

Some places do not allow water storage tanks that are designed for long term holding. I know my area does not. Even an in-line tank may not replenish the held water adequately and could present a breeding ground for bacteria and other micro-organisms as well as concentrations of chemicals used for water treatment. For this reason, even if it were allowed, I would not do it for my own home.
Water that comes in from the city may be treated but it is not sterile.
Just to be on the safe side, it wouldn't hurt you to call your local health department and see if they have any concerns.

Thanks for the replies. I will give the local health department a call and see what they say. But I'm going to be storing water one way or the other, so I feel like having an inline tank will be the way to keep water the freshest.

Shouldn't it rotate pretty well if the intake is on the top and outlet on the bottom?

This is my design using 40 gallon water heater tanks as cold water storage
the dip tube must be removed.

I strongly, Recommend A water purify testing kit. and monthly testing of the water in each tank. I have, on the top of each tank a ball valve, for introducing
what chemicals as the test requires

On city water, if there is no water pressure from the city, you have no pressure in the house to move the hot or cold water to the faucets. Without air, water can not be pressurized. So I don't see how this idea would benefit you in any way without a pump or compressor.

SB, I'm confused. What Frodo drew was exactly what I was going to do. You have city water, which flows through these storage tanks, then continues to your faucets. If the water source was shut down for any reason these stand by tanks could be utilized for potable water by way of a gravity fed drain. What am I missing?

gravity..open the valve on top of tank, open drain wATER!!!!!!!!!!

Just to expand on this thought, since the incoming water is already treated with chlorine, and it is in a looped system, would there really even be a need to add chemicals to maintain the water? Seems the water would be first in/first out?

SB, I'm confused. What Frodo drew was exactly what I was going to do. You have city water, which flows through these storage tanks, then continues to your faucets. If the water source was shut down for any reason these stand by tanks could be utilized for potable water by way of a gravity fed drain. What am I missing?

Click to expand...

Now that I see his elevated tank second drawing, there is nothing wrong. It would work fine. Air in the top, water out the bottom. Gravity will take care of the pressure problem. Taking showers however could be difficult.

havasu said:

Just to expand on this thought, since the incoming water is already treated with chlorine, and it is in a looped system, would there really even be a need to add chemicals to maintain the water? Seems the water would be first in/first out?

Click to expand...

when a minuscule chance ... for the health of your family, test it.
only takes 5 minutes and a 5 dollar litmus test paper