Quick Facts
Location
Black Mountain, North Carolina
Role
Prime Contractor
Completion Date
November 2020
Phillips Contribution
Phillips began these improvements in November 2017. The main scope of work was the construction of the new auxiliary spillway, which is approximately 200’ wide and 600’ in length. The control section of the spillway was a Hydroplus design called Fusegates. Earth and rock had to be excavated to reach the subgrade of the spillway, and material excavated from the spillway was used to buttress the two existing earthen dams, reducing their slope from 2:1 to 2.5:1. A new seepage collection system was also installed prior to the placement of the buttress material.
Due to the placement of the buttress material, the conduit that supplies raw water to the water treatment plant had to be extended. The extension was achieved by casting in place a structural concrete vault that will house a new 36” ductile iron pipe. To avoid interrupting plant operations, a temporary pumping system was installed during the conduit extension. Modifications were made to the existing intake tower, and the principal spillway was rehabilitated, including the installation of new Obermeyer spillway gates.
AWARDS
- 2021 ASDSO National Rehabilitation Project of the Year Award
