Diamond Valley Lake Design Project, City of Los Angeles, California



Metropolitan Water District (MWD) of Southern California



Tunnel Design; Data Management; GIS Support; Technical Specifications; Preliminary & Final Engineering; Design of Earth/Rockfill Dams; Site Characterizations; Environmental Permitting Support; Design of hydraulic structures; Design of Pump Generating; Plant and Switchyard; Design of Generating Plant


The Diamond Valley Lake Project involved the design and construction of several components of this reservoir:

  • An earthfill/rockfill embankment on the west end, 1.8 miles long and 280 feet high that required 54 million cubic yards of fill and excavation of 60 feet to a hard alluvial foundation;
  • An earthfill/rockfill embankment on the east end, 2.2 miles long and 180 feet high that required 330 million cubic yards of fill and excavation of 90 feet down to bedrock;
  • A large roller-compacted concrete saddle dam along a low point in the hill that forms the northern boundary of the site and a saddle dam that required 1 million cubic yards of fill; and
  • A pump generator (P/G-1) and fore bay at the north abutment of the west dam and substation; a generating Plant (G2) at the head of the San Diego Canal and a substation; and an inlet/outlet structure and tunnel.

DRC staff provided various analyses, using an integrated resources management approach that included containment and control plans and collection and distribution systems modeling. The project also included relocating seven miles of Newport Road, which formerly ran through the valley; 1.5 miles of the San Diego Canal; and utilities. DRC also support the design of a 54-inch diameter treated effluent pipeline, approximately 11,000 lineal feet long.