Orland Unit Regulating Reservoir


The Orland Unit Regulating Reservoir Project included the construction of a 49.5 acre feet regulating reservoir with a compacted bottom, concrete lined slopes, inlet and outlet control structures. The scope of work also included building a reservoir access canal crossing, construction of a raised canal section, raising of two existing bridges, a new farm turnout structure, construction of four lateral headings, five 2-bay long crested weirs and 1 single-bay long crested weir.

This project included additional challenges involving scheduling and coordination as we were only permitted to work in the irrigation distribution system during the months of December, January and February when the irrigation system was not in use. Diamond D self performed the reservoir earthwork, dewatering, demolition, excavation, cast in place concrete, and placement of HDPE storm drain pipe for all inlets and outlets. Additionally, Diamond D placed a new shotcrete liner in the surrounding area of each structure and built galvanized access platforms and handrails for all of the new structures. We worked together with the Orland Unit Water Users’ Association to overcome various project obstacles, which led to a solid relationship between the owner and the contractor and the successful completion of the Orland Unit Regulating Reservoir Project.


  • Moved 25,000 CY of soil to construct reservoir.
  • Pour over 600 CY of structural concrete.
  • Installed various dimensions of HDPE water tight storm drain pipe.
  • Fabricated and Installed 18 galvanized access platforms.
  • Placed 105 CY of shotcrete for canal lining.
  • Implemented and Maintained Storm Water BMP’s.

Owner: Orland Unit Water Users’ Association

Contract Value: $900,252.70 Completion Date: April 10, 2012

Reference: Available Upon Request