OCR Text |
Show lion tons of sulfate, 5.1 million tons of calcium, and 2.7 million tons of sodium, potassium, and chloride. All of this material has remained in solution except for 3.6 million tons of calcium which have combined with carbonate and precipitated in the lake (p. VIII-264). According to Howard, the precipitation of calcium carbonate has resulted in a loss of 5.6 million tons of carbonate from the Colorado River water as it passed through Lake Mead from 1935 to 1948. Likewise, there has been a loss of about 1.0 million tons of silica during this same interval owing to its precipitation in the lake. In summary, Howard's data show that about 20 million tons of soluble material have been dissolved from the reservoir bed and banks and that about 10 million tons of dissolved solids have been precipitated in the lake from 1935 to 1948. These changes have resulted, therefore, in a net gain of about 10 million tons of dissolved solids in the Colorado1 River water as it passed through Lake Mead. The average salinity of the water discharged at Hoover Dam and the average salinity of the water stored in the lake are higher than the average salinity of the inflow. Solution of soluble materials from the reservoir boundary has resulted in higher concentration of calcium, sulfate, potassium, sodium, and chloride in the lake water and outflow than in the inflow. On the other hand, precipitation in the lake has produced a lower concentration of carbonate and silica in the lake and outflow than in the inflow. The large quantities of calcium and sulfate that have been dissolved from the reservoir boundary show that the solution of gypsum and anhydrite is much greater than the solution of rock salt (halite, sylvite, etc.), represented |
Source |
Original book: [State of Arizona, complainant v. State of California, Palo Verde Irrigation District, Coachella Valley County Water District, Metropolitan Water District of Southern California, City of Los Angeles, California, City of San Diego, California, and County of San Diego, California, defendants, United States of America, State of Nevada, State of New Mexico, State of Utah, interveners] : |