Plumbers in Tulsa, OK

A shelter full of water is not a shelter

Below-ground storm shelters are ordinary building stock here in a way they are almost nowhere else, and they present a plumbing question that rarely gets asked.

A sunken shelter is, physically, a container set into the earth. Water gets into it: past the door seal, through the walls, or simply as groundwater rising after a wet spell.

Without drainage, it accumulates. And the entire value of a shelter is that it is usable at a few minutes’ notice, which one holding standing water is not.

The awkward part is that nobody finds out until they need it, because a shelter is opened rarely. It is entirely possible for one to have been slowly filling for two seasons with nobody aware.

Test the drain you already have

Most shelters were built with some form of drainage. The question is whether it still works.

Shelter drains are small, they sit at the lowest point in the structure where sediment naturally collects, and they go years without being looked at. They silt up quietly.

The test is a bucket of water and thirty seconds of watching. Pour it in at the low point and see what happens. It should clear steadily. If it sits, pools, or drains very slowly, the drain needs attention.

There is a second possibility worth checking: that the drain was piped somewhere it cannot actually discharge. On a flat site, a gravity drain needs somewhere lower to go, and if there is nowhere, it was never going to work regardless of how clean it is.

Where gravity is not available, a small pump with a float switch is the answer. It sits idle, costs very little, and runs when the shelter takes water.

Either way, arranging it on a dry afternoon is considerably easier than discovering the problem during a warning.

Slabs, clay and the meter

Most local housing sits on a slab over clay that moves with the seasons.

The clay swells when it takes on water and shrinks through a dry spell. The slab moves with it, and the copper cast into the slab moves too. Hot water lines give way first, because they run warmer and cycle harder than the cold.

Because the pipework is in concrete, a leak produces nothing visible for a long time. The meter is what finds it early.

Everything off, including irrigation and the ice maker. Note the reading. Come back an hour later without using water. A changed figure means water is escaping.

After that, the signs that point specifically at the slab are a warm patch on the floor with nothing beneath it, running water audible with everything off, new cracking in tile, or a musty smell along one wall.

Ice, and a house with no heat

Winter here does not drive frost deep into the ground, so the northern advice about burial depth does not apply in the same way.

What does happen is ice storms, and ice storms bring down power lines. A house without heating for several days in freezing weather is how a pipe freezes in this climate.

So the preparation is about outages rather than insulation. If one looks likely to last, shut the water off at the main and open the taps to drain the system down. Water that is not in the pipe cannot freeze in it.

Short of that, let taps drip on the most exposed runs, open cabinet doors under sinks on exterior walls, and keep the building as warm as circumstances allow.

And find the main shutoff before you need it, because a pipe that split while frozen does not leak until things thaw, and then it arrives all at once.