Page - 74 - in Book of Full Papers - Symposium Hydro Engineering

chute, the completion of these features could extend a few months into the 2017- 2018 Winter Flood Season if the FCO Spillway chute measures were completed by November 1, 2017. The RCC buttress and apron would be completed during the 2018 construction season. Fig. 7 2017 and 2018 repair/improvement monoliths/weir measures selected for Emergency Spillway 3. DESIGN AND CONSTRUCTION PROCESSES 3.1. CONSTRUCTION CONTRACTING APPROACHES During the Emergency Response phase, several construction contracts had been awarded by DWR to help manage the emergency, including contracts to temporarily armor the Emergency Spillway and for dredging the Diversion Pool (Feather River) immediately below the FCO Spillway chute and dentates to remove eroded rock and concrete [1]. However, the restoration work under OER could not begin immediately after the incident occurred in February because: (1) the FCO Spillway chute had to be used intermittently between February and May to release the record reservoir inflows to avoid use of the eroded Emergency Spillway, thus preventing any work on this facility until late May; and (2) the designs for the various repair/replacement measures were not yet developed or approved by dam safety regulatory agencies. Yet there was a critical need to start recovery work as soon as possible given the very short 2017 construction season. As a result, DWR proceeded with the following approach:  An initial construction contract (Specification No. 17-08) was advertised on March 21, 2017, and awarded to Teichert Construction on March 27 for a low-bid amount of $5.8 million. This first contract was used to construct access roads and staging areas that would be used later for the FCO Spillway chute recovery work. It was also used for the initial excavation work around the upper portions of the scour holes to help stabilize the slopes so that construction work could be safely done beneath the overly steep 74