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ill H ofsratiqb or watsh supply system Xh® intake puapa at Lake Mead are completely automatic and require no attend­ant. puapa are started and stopped by float aoatrol from the Booster Station. Reservoir* The starting sad stopping of the pumps is in measured sequence which is governed by the setting of the float switches to prevent excessive surge. Should sll pumps stop at the same time due to power failure the capacity of the surge suppressors is sufficient to prevent a dangerous strain on the press\ire pipe line. These pumps require little maintenance work, and the installation is as simple and no different than that of any other deep well pump installation. At the booster reservoir, in addition tp the six float switches for the con­trol of the six intake pumps, there is a float switch for the protection of the booster pumps* Should the intake pumps fail this float switch would cut out the booster pumps before water in the Booster Station Reservoir became dangerously leer* fhe booster pumps were designed for either float control from the Terminal Reservoirs, remote manual control or manual control at the pumps. The re­mote manual control board is now located in the electrical control house at the Magnesium plant. These pumps are equipped with every electric and hy- craulic protection which may ever be necessary, a complete description of which would be too lengthy for this report. Unlike the intake pumps, when starting or stopping, the timing relays for all the puapa in service are gneraized simultaneously with the time setting being set to effect the desired starting and stopping sequence. For our normal operation but three pumps have been in service at one time; however the true maximum capacity of this station is reached when five pumps are in regular service and the sixth is used as a standby. In the discharge pipe from the Booster Pumps,just outside the building, there is a venturi tube with a 17 inch throat connected with a meter in the pump room. The meter is a Builders Providence instrument of the recording, in­dicating and integrating type. Payments tc the Colorado River Commission are based on readings taken at this meter. About four miles below the Terminal Reservoirs a 12 inch O.D* line takes out of the 40 .Inch pressure main for water supply to Manganese Ores Company. The Manganese Ores supply is stored in a one million gallon tank, whose water surface is 47 feet six inches lower than the inlet to the Terminal Reservoirs. Ths connecting pipe line and storage tank are the property of Manganese Ores Co. At present the Manganese Ores Company us© shout 1.25 million gallons per day. At the Terminal Reservoirs the 40 inch pressure pipe line enters a reinforced concrete box whioh is bifurcated to divide the flow between each reservoir. There is a gate at each antranee to permit taking either reservoir out of service when necessary for cleaning or repairs. It has been found that algae grows rapidly in these reservoirs if it is not controlled. About three pounds of CuSO^ per million gallons of water will keep the alga® under control. The designed capacity of the Water Treatment Plant is twenty million gallons per day. Proper operation requires the servicesof the following personnelt §