-t '-ea'm. until" the 'horizontal strata of the plains are reached. Its 

 main tributaries all come from the western side, and they too are 

 mountain streams rising in the White, Sacramento, and Guadalupe 

 mountains. In time of floods these streams run large quantities of 

 water throughout their courses, but during the greater part of the 

 year they disappear, being absorbed in the sands and gravels of their 

 beds soon after leaving the mountains. The numerous springs all 

 along the west bank of the Pecos indicate that much of this water 

 appears again as seepage water after a long journey under ground. 



THE IRRIGATION SYSTEMS OF THE PECOS. 



There are four large systems of irrigation on the Pecos River in 

 New Mexico and Texas : 



1. The Roswell area, deriving water from the North and South 

 Spring rivers and the Berendo Springs. 



2. The Hagerman area or Northern Canal System, the water for 

 which is obtained from the unused, waste, and drainage waters from 

 the Roswell area, and in time of flood from the Hondo River. 



3. The Carlsbad area or Southern Canal System obtains water 

 directly from the Pecos River by storage in two large reservoirs. 



4. The Barstow area also receives water from the Pecos, but with- 

 out storage. 



ROSWELL AREA. 



The Roswell area is confined to the land immediately around the 

 junction of the Hondo and Pecos rivers, with narrow strips along 

 the Berendos. The waters of the North and South springs come 

 from great depths in the Hondo flood plain, and no doubt are a part 

 of the water lost through seepage from the upper part of the rivers 

 and tributaries just after they leave the mountains. The water con- 

 tains on an average 75 parts of soluble matter per 100,000. Of this, 

 only 35 parts are likely to remain in solution and accumulate within 

 the soil, to the detriment of plant growth. The remaining 40 parts 

 crystallize out on evaporation and concentration of the water, and 

 are not readily soluble thereafter. The waters of the Berendo 

 Springs, which come from the great gypsum plains, extending to the 

 north along the Pecos, are not so good, as they contain 250 parts of 

 soluble matter per 100,000, of which about one-half is likely to accu- 

 mulate in solution upon evaporation of the water. The lands to 

 which Berendo water is applied all lie close to the stream banks and 

 have good underdrainage, so that no damage has resulted from the 

 use of this saline water. There is no black alkali or sodium carbon- 

 ate in the Pecos Valley, so far as observed. 



