HYDRAULIC METHOD USED FOR MOVING SAND 

 AT HYPERION BEACH EROSION PROJECT, EL SEGUNDO, CALIFORNIA 



I. GENERAL DESCRIPTION 



Peter Kiewit Sons § Company and Construction Aggregates Corporation, 

 Joint Contractors and Coadventurers, had the contract from the city of 

 Los Angeles for repairing the beach erosion from El Segundo to the Venice 

 Pier. 



The earth and sand material for filling were obtained from the sand- 

 hills (relic dunes) along the beach near the Hyperion Sewage Disposal 

 Plant. The hydraulic method for moving material has been employed. The 

 system as used was developed by Mr. Sensibar of Construction Aggregates. 

 Certain details of the system have been forwarded to the United States 

 Patent Office for patenting; other phases have been in use for a con- 

 siderable number of years. 



A general discussion of the Sensibar method of moving the material 

 suspended in water through pipelines from one point to another follows: 



Water under pressure is forced through a nozzle onto the sandhills 

 from which the material is to be obtained. The sand suspended in water 

 is sluiced down to a sump or low area where a sand eductor is located. 

 The eductor draws in the slurry (sand suspended in water) by siphon action, 

 and discharges it into a pipeline extending to a surge pit and thence 

 through the surge well to the dredge pump suction. The water-sand mixture 

 is then drawn into a pump and discharged through a series of pumps and 

 pipelines to the area into which the material is to be deposited for 

 filling. 



A description of the actual operation at the El Segundo-Hyperion 

 plant follows: 



About 300 feet from the shoreline, a pump station was built. Four 

 28-inch dredge pumps are located in this area with all necessary equipment 

 for operation and maintenance. Two 36-inch pipelines 800 feet long 

 forming a "Y" at the pumphouse, are sea-suction lines and extend out into 

 the ocean parallel to each other and about 50 feet apart, for a distance 

 of about 500 feet beyond the shoreline and 6 feet below the centerline of 

 pump No. 1. From the "Y" connection, a single 36-inch line connects to pump 

 No. 1, which draws in seawater at from 15 to 20 inches of vacuum. The 

 water is discharged at a pressure ranging up to 80 pounds per square inch 

 into a 30-inch line which is enlarged to a 36-inch intake line for pump 

 No. 2 located in the same pumphouse at right angles to pump No. 1 and at 

 an elevation about 9 feet above pump No. 1 from center of the discharge 

 on pump No. 1 to the center of intake on pump No. 2. Pump No. 2 increases 

 the pressure of water from 80 to about 160 pounds per square inch, and 

 discharges into a 36-inch main-pressure line which runs parallel to the 

 intake line, about 300 feet long, and extends toward locations in which 



