In Texas, everybody knows that you need to water your foundation during the summer. It is also common knowledge that if you do not water your foundation, you are risking foundation damage.
What most people do not realize is that winter droughts can also damage foundations. So far this fall (October and November) the DFW area is way behind in rainfall. The normal rainfall for October is 4.8 inches and for November it is 2.9 inches for a total of 7.7 inches. So far this fall, including the inch we just had in December, we have only had 3.8 inches of rain, less than half of normal.
Why are we in a drought? Every 10 years or so, the surface waters in the Pacific Ocean warm up and the warm water drifts towards California. The warm water typically causes the weather in the southern plains, which includes Texas, to be warmer and dryer than usual. The long-term forecast is for the weather to stay warmer and dryer than normal into the spring.
Normally, as the fall and winter proceed, the soils gradually absorb water. As the soils absorb water, they swell up, reversing settlement that took place during the summer. The below normal rainfall that we have had means that the soils are actually drying out. Instead of summer settlement being reversed, the soils are still settling. As soils dry out, they shrink, and that can cause foundation damage.
So, what should you do? You should continue to water your foundation, although you should reduce the amount of water that you add to the soil. A small amount of water in the winter goes a lot further than the same amount in the summer because there is so much less evaporation. As long as the weather stays dry, continue to water your foundation, but cut the amount of water in half. If you find that the soils around your house are becoming too wet, cut back the amount of watering. On the other hand, if you see signs of settlement, consider increasing your watering.
If we are fortunate enough to have a period of sustained rain, say 5 or 6 inches in a month, you can stop watering until the spring comes. In the meantime, keep those hoses running!