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DESCRIPTION OF IRRIGATION WORKS AND PROJECTS.

EASTERN GULF COAST REGION.

The humid part of the State may be considered as that having a mean annual precipitation of 40 inches or more. This comprises the greater part of the State east of the city of Dallas and of the lower Brazos River. The rainfall over this area is usually abundant, and irrigation in the northern and central portions of this humid region will not probably become of any considerable importance, but in the southern end, along the coast, there exist large tracts of land adapted to rice growing, and the greater portion of this will probably be used for this purpose.

This land is mostly a flat prairie, locally called swale land, covered with a coarse growth of grass and having such a gentle slope toward the sea as to be but little removed from a marsh during a large part of the year. It extends inland for several miles and is cut by numerous bayous, in which the tides from the Gulf ebb and flow and the waters gradually become brackish as they near the Gulf. Most of the rice farms lie along these bayous, and from them the principal supply of water is derived. The farms are so located as to insure a supply of fresh water. The soil along the bayous is much richer than the prairies and yields heavier crops.

The manner of cultivating and irrigating is very different from the South Carolina system, where the water is held by artificial storage reservoirs or raised above the level of the fields by the action of the ocean tides, which back up the flow of the rivers at each tide to a height sufficient to reach the fields. In this part of Texas storage reservoirs are used in only a few cases, most of the fields being supplied by pumps placed on the banks of the bayous and operated by steam power. The land is laid off in much the same way as on the eastern plantations. The work in this State is newer and therefore rougher, but the main features are the same. The fields are surrounded by low levees to hold the water on the land, and are ditched to permit. drainage at the lowest point.

Nearly all of the land planted with rice is irrigated, as those who have attempted to grow it without irrigation have lost their crops two years out of five and made only very short crops during the other three years. As previously stated, the water is supplied to the fields by pumps run by steam power, rotary pumps of the Menge pattern being most frequently used. These are operated by engines of from 10 to 70 horsepower or more, and have a pumping capacity of from 1,500 to 8,000 gallons per minute, or from 3.34 to 17.82 second-feet. The lift varies from 9 to 12 feet, and the pumps are run night and day during the irrigating season, which lasts from sixty to ninety days, thus delivering from 400 to 3,000 acre-feet of water. For the prairie farms the water is carried in canals, either on the surface or