Oroville Spillways Construction Update - July 25


Leveling concrete is pumped onto a section of the upper chute of the Lake Oroville main spillway.

Leveling concrete is pumped from a long crane onto a section of the upper chute of the Lake Oroville main spillway during Phase 2 of the recovery effort at the dam in Butte County, California. DWR/2018

SACRAMENTO – Today the Department of Water Resources (DWR) provided an update on construction-related activities for the Lake Oroville Spillways Emergency Recovery Project.


Construction on the Main Spillway

  • Crews have completed foundation clean-up and placement of dental and leveling concrete on the uppermost 730 feet of the spillway chute. Slab formwork construction will begin next week, and placement of structural concrete slabs will start Monday, August 6.
  • Placement of structural concrete slabs and walls continues on the middle chute. Crews have placed 66 of 228 slabs and 8 of 76 walls to date. 
  • Crews will complete the mechanical demolition of the energy dissipaters, or dentates, at the base of the main spillway by the end of the week. Crews will place reinforcing steel and concrete framework in the coming weeks. Placement of structural concrete is anticipated to start by the end of August.
  • November 1, 2018 is a public safety construction milestone to complete placement of all structural concrete on the main spillway. Dry finishing, concrete curing, joint sealing, completing sidewall backfill and site clean-up will continue on the main spillway after November 1.


Construction on the Emergency Spillway

  • Crews started placement of roller-compacted concrete on the southern half of the emergency spillway on Monday, July 16. The RCC buttress at the base of the emergency spillway weir will be built later this year.
  • Work at the emergency spillway site is not dependent on the public safety construction milestone and will continue past November 1, 2018.


Other Updates

  • Oro Dam Blvd East between Glen Drive and Canyon Drive will reopen to pedestrians and  vehicles on Monday, July 30. The speed limit on this stretch of Oro Dam Blvd East will be reduced to 25 mph and cars will not be allowed to stop on the road. There are several designated turnouts for cars to pull over for a view of the reconstruction work.
  • Last week, DWR convened the inaugural meeting of a community-led group of local elected officials and stakeholder organizations - known as the Ad Hoc Group - as part of the recently initiated Oroville Dam Safety Comprehensive Needs Assessment. The Community Ad Hoc Group will meet regularly with DWR and the Independent Review Board of experts to be briefed on elements of the Comprehensive Needs Assessment so its members can inform the community interest groups they represent. Meeting materials and a video can be found on the DWR website.
  • Day-use and boat-launching will be free at Lake Oroville State Recreation Area on August 2 and 3 and September 6 and 7 as part of DWR’s free access program.
  • More than $30 million in recreation improvements are underway to build new boat ramp lanes, extend existing lanes for low-level water access and add new site amenities at recreation sites throughout the Lake Oroville State Recreation Area.


To view photos and video of the Lake Oroville Spillways construction, visit DWR’s Oroville Spillway photo gallery and YouTube channel.




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