In Case of Emergency


Emergency Response

Project Name

Oroville Dam Spillway Emergency Response



Year Completed


Location Information

Lake Oroville – Oroville, California


2018 AGC of Cal­i­for­nia Con­struc­tor Award

Meet­ing the Chal­lenge of the Dif­fi­cult Job: Heavy Engi­neer­ing


2017 AGC of Cal­i­for­nia Safe­ty Award of Excellence

Safe­ty on a High Haz­ard Project

Project Sum­ma­ry

In ear­ly Feb­ru­ary 2017, dur­ing wide­spread rain­fall in Cal­i­for­nia, oper­a­tors at the Oroville Dam facil­i­ty began mak­ing releas­es down the main spill­way, but soon observed an unusu­al flow pat­tern caused by dam­age to the mid­dle por­tion of the Lake Oroville main spill­way. Syblon Reid was con­tact­ed by DWR and asked to serve as the prime con­trac­tor for the emer­gency response and sta­bi­liza­tion work. The ini­tial tasks includ­ed: estab­lish­ing and main­tain­ing con­trol of the exist­ing main spill­way gates; clear­ing trees from below the emer­gency spill­way in antic­i­pa­tion of it over­top­ping for the first time since it was con­struct­ed; and imple­ment­ing debris removal oper­a­tions – both below the spill­way and at the down­stream diver­sion dam – to pre­vent foul­ing of the diver­sion dam gates and flood­ing of the 819 megawatt Hyatt Pow­er­plant. Once the flows over the aux­il­iary spill­way ceased, the scope rapid­ly increased to address mul­ti­ple tasks; the pri­or­i­ty of which was pre­vent­ing the pow­er­plant from flood­ing and main­tain­ing it as an oper­a­tional facil­i­ty. The expand­ed scope also includ­ed plac­ing large rock and con­crete in the erod­ed areas below the emer­gency spill­way and exten­sive dredg­ing – both from the shore and off barges – to remove the mas­sive debris plug in the Feath­er Riv­er below the main Spillway. 

Key Chal­lenges

As the prime con­trac­tor, Syblon Reid both self-per­formed and orches­trat­ed the con­struc­tion response efforts, which com­prised over 50 sup­pli­ers and sub­con­trac­tors. This involved coor­di­nat­ing of over 150,000 labor hours and mobi­liz­ing and man­ag­ing over 130 pieces of heavy equip­ment, three 50-plus meter boom con­crete trucks, four sup­port heli­copters, 180 rock deliv­ery trucks, six large barge assem­blies with long-reach exca­va­tors, nine work boats, mul­ti­ple tracked drills, sup­port vehi­cles, and mis­cel­la­neous equipment.