The farmer, in most areas of the state, could grow certain crops without paying anything for water. After all, rainfall a farmer can hold on his land is as free as the air and the sunshine. Low and variable annual rainfall has resulted in 60 percent of all crops in the state receiving irrigation water to supplement rainfall. If rainfall runs off of the farmer's land into a stream or lake, it becomes the property of the state and can only be used with the state's permission. State laws and regulations determine who has the right to use the surface water and also which users have priority.
Irrigation comes after municipal and industrial uses in priority.
This means that as demands increase or droughts occur, surface water will be used for these higher priority uses instead of for irrigation. Unless the farmer's land is adjacent to a river, he must pay the costs of water delivery. Since most surface water used for irrigation is first stored in large reservoirs, the cost of the water reflects the expense of development and storage as well as the cost of delivering the water. Eighty-two percent of all irrigation in Texas, in fact, is now using water from underground sources. Water beneath a farmer's land is free because it is legally his property, but he must pay for the well, pump, and energy required to bring the water to the surface.