Will 110 gal of water ruin my foundation?

I just purchased two of WaterPrepared’s 55 gal water tanks: https://waterprepared.com/products/blue-55-gallon-water-storage-tank. My plan was to store them in a corner of our outdoor shed, which is built on a concrete foundation. When I went to clear out that part of the shed, I noticed that there is severe cracking in the foundation all along the wall. See photo.


I don’t know if this is caused by:

1) the 400 lbs of water that is already stored on that side of the shed in 5 gal containers. But the water wasn’t stored in that corner–the row of 5 gal containers starts on the cardboard on the left side of the photo.

2) the current drought which is drying up our clay soil so that it contracts underneath the foundation. This is a major problem in our area; we have to put soaker hoses around our home’s slab foundation to keep it evenly moist or it will crack. We don’t have soaker hoses around the shed.

It’s only a shed, so I’m not very concerned about the foundation cracks. But I don’t want them to get majorly worse, like having that side of the shed sink 3 inches into the ground! Do I need to find a different place for the two 55 gal water tanks? Maybe putting them on the other side of the shed would be sufficient. I had hoped to be able to stack them in order to save space, which would mean about 900 lbs resting on about 4 sq. feet of space.


  • Comments (7)

    • 1

      Does the door, walls, and roof all look straight and level? Those might be signs of sinkage that would be an issue but maybe if those are all good then the crack might not mean it’s too bad… 

      I don’t know enough about foundation issues to know what might be causing it or if 900lbs of water would cause it to worsen.  I know too much water can cause issues, but I didn’t know that too little water could cause it as well. 

    • 2

      Hard to speculate. Place a straight edge across the crack, if both sides are level it is probably shrinkage, if not level it’s probably settling. The strength will depend mostly on how much reinforcement there is in the slab and how thick, for a shed maybe not much.

      At any rate, I’d at least lay down a couple of 4x4s to distribute the weight. Be careful, 500# up in the air could squash someone if it is unbalanced or gets that way.

      • 1

        Good tip to lay down some boards to distribute the weight. That would be an important tip to prevent further damage.

    • 3

      The pieces of concrete that have broken from the main slab will sink and continue to sink unless you repair the slab. Bad news, I know, but I speak from experience.

      Once I discovered the corner of my work shop slab had cracked and broken I stopped stacking anything in the corner, but the piece still sinks a little more after every heavy rain, and now after three years the corner of the shop (walls, ceiling, etc.) are sinking with it to the point the door doesn’t open or close properly.

      Getting a quote for repair, but have been told it will have to be cut away, dug up, and re-poured. If they find the foundation underneath (if there is one but not likely) is also broken, the cost will go up.

      • 1

        Thanks for the feedback!

      • 2

        If it is just a small detached shed, the foundation probably is not very thick. Might be a fun project to dig out the sides and pour in more cement to stabilize it. Should be much safer to do on your own than doing it on your house.