Lake Oroville Spillways Emergency Recovery Construction Continues

By on July 27, 2018

The Department of Water Resources (DWR) provided the public with a construction update on the status of the Lake Oroville Spillways Emergency Recovery Project this past Wednesday. Of special note was the convening of the inaugural meeting of a community-led group of local elected officials and stakeholder organizations – now known as the Ad Hoc Group – as part of the recently initiated Oroville Dam Safety Comprehensive Needs Assessment (CAN). The Ad Hoc Group will meet regularly to be briefed by DWR and the Independent Review Board of experts on portions of the CAN. The Ad Hoc Group is subsequently responsible for informing the group they represent of the CAN information and other pertinent news.

Construction crews have now completed the foundation clean-up of the main spillway and have placed dental and leveling concrete on the uppermost 730 feet of the spillway chute. Construction of the slab formwork is slated to begin next week; placement of structural concrete slabs will start Monday, Aug. 6.

Mechanical demolition of the energy dissipaters, or dentates, at the base of the main spillway are targeted for completion by the end of this week. Other crew members will begin placing reinforcing steel and concrete framework in the coming weeks. Placement of structural concrete is anticipated to start by the end of next month.

Construction crews are working toward a November 1 deadline for the public safety construction milestone and the completion of the 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.

Placement of structural concrete slabs and walls continues on Oroville’s middle chute. Crews have placed 66 of 228 slabs and eight of 76 walls thus far.

As for the emergency spillway, crews started placement of roller-compacted concrete (RCC) on the spillway’s southern half on 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 part of the public safety construction milestone and work will continue past Nov. 1.

Beyond the work on the spillways, other projects are underway in and around Oroville Dam. Pedestrian and vehicle traffic on Oro Dam Blvd. East, between Gen Drive and Canyon Drive, will resume on Monday with a reduced 25 mph speed limit. Although vehicles 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.

More than $30 million in recreation improvements are underway throughout the Lake Oroville State Recreation Area including new boat ramp lanes, extending existing lanes for low-level water access and adding new site amenities at recreation sites. Day-use and boat-launching will be free at Lake Oroville State Recreation Area on Wednesdays and Thursday, August 2 and 3 and September 6 and 7 as part of DWR’s free access program. For more information go to: