IRRIGATING DESERT LAND
The national irrigation idea had its birth in Los Angeles in 1890, when the business men of that city met and opened a campaign for securing a Government system. Nearly six thousand letters were written and mailed to representative men of the country with the result that the idea took root and national irrigation became an accomplished fact.
Before the Government passed laws whereby irrigation became a national charge, private enterprise had taken hold of the matter, and the Imperial canal had been started out into the Colorado Desert. This canal has had marvelous development, and two years from the time work was begun upon it more lands had been reclaimed than by any other single irrigation system in the world.
The work of reclaiming the Colorado Desert was begun in 1900. Not far from the Mexican line, at Hanlon's Crossing, the river left a convenient place for the headworks of the great canal. Here is where the river was tapped. About a mile from the headworks the river, which in the bygone ages laid down the sixty-mile barrier between the gulf and the desert, also left a channel whereby to aid in reclaiming the desert. The first ten miles of this natural channel required some deepening, and then for some sixty miles across the Mexican border and back to the international line the canal was ready-made.
From the point where the canal leaves the Colorado to where it returns to the international line, after circling through Mexican territory, there is a fall of one hundred and fifteen feet, less than two feet to the mile. This, however, is sufficient for the purposes of irrigation.
One of the first questions to be settled, when the project for leading the river out into the desert was considered, was the character of the water. Not all water found in the arid regions is good for irrigation. Much of it is so impregnated with alkali as to be injurious rather than helpful to the soil.
The University of Arizona made daily analysis of the waters of the river for a period of seventeen months. This analysis showed that the waters contained no injurious substances, but, on the contrary, much that is nutritive to the soil.