Bluestone Dam

Location: Hinton, WV
Owner: US Army Corps of Engineers, Huntington District
General Contractor: Brayman Construction Corp.
Value: $74.9 Million
Date Complete: In Progress

Dam Safety Assurance Phase 2B - This project involves the installation of 150 high capacity rock anchors ranging from 6 to 61 strand anchors to upgrade the stability of the existing dam. With rock anchors as deep as 275ft and the close proximity of adjacent anchors, drill tolerances of 1:150 are required so that the rock anchors do not intersect embedded items in the dam or other anchors. Brayman utilizes directional drilling techniques to satisfy such tolerances. The project also includes the design and construction of two temporary soil nail walls, excavation and placement of 13,000cy of embankment along with the extension of three (3) penstocks.

Modification Phase 2 – Spillway anchors – Through our proven success with the installation of the dam anchors in the beginning phase, our team negotiated directly with the USACE for the installation of an additional 66 anchors. This scope also included the design and construction of a steel platform on the spillway to support anchor operations. The platform was able to support two, 85-ton crawler cranes in addition to multiple drill rigs and other support equipment. These anchors were located in both the east abutment and spillway sections. Similar to the initial dam anchors, the anchor holes required a minimum tolerance of 1:150.

Apron Drains - Work was performed on relief drains located in both the inspection gallery and in the apron of the spillway. The gallery work included cleaning existing drains by enlarging the drain diameter by 1/4in for the entire length for over 15,000lf of reaming. Additional drains were installed by coring drilling at 40 locations to depths up to 120ft. Vibrating wire piezometers were installed at 8 (eight) of the relief drain locations. The spillway apron work was performed from barges located in the stilling basin downstream of the dam. Existing relief drains tied to a drainage network were extended up to 25ft at 12 locations. Divers were used to locate the existing drain holes and verify the installation angle.