Stilling Basin Repair, Foster Joseph Sayers Dam, Beech Creek, PA

The project consists but is not limited to the repair, construction and installation of the following: The area around the stilling basin is heavily used for fishing. The contractor shall erect temporary fencing and signage around the work area, sufficient to prevent pedestrian access into the work area. Temporary fencing and signage shall also be erected around the contractor’s staging area. For any required vehicular access to the south side of the stilling basin, due to the steep slopes, the contractor shall construct a temporary ramp with fill materials that shall be removed at the end of construction. A water diversion and dewatering system shall be designed by a registered Professional Engineer, and constructed to allow for controlling the upstream reservoir level and downstream river level. The water diversion system shall be designed to carry a design discharge of 700 cubic feet per second. Due to reservoir regulations, water diversion and dewatering shall not begin until 1 June. Dam flow shut downs cannot exceed 1 hour, with a waiting period of 1.5 hours between shut downs. The temporary water diversion shall remain in place and the basin shall remain dewatered for a minimum of 28 days after completion of concrete placement. The diversion system shall not be dismantled until approval of all work. The basin shall be monitored for movement by survey methods throughout the work. Monitoring is required to detect any uplift of the basin or sideways movement of the walls. Several monitoring points shall be established and readings shall have an accuracy of 0.1 inch. Monitoring shall be required at one hour intervals during the initial dewatering of the basin, and at daily intervals thereafter, throughout the duration of the work. The contractor shall submit his monitoring plan for approval. Concrete repairs and geometric changes to the channel shall be constructed, for the purpose of improving the flow characteristics, so that the channel is no longer damaged by backward circulating riprap. Concrete repairs shall be by the placement of Silica Fume Concrete and epoxy coated reinforcing steel. Contractor to conduct 3D laser scanning (also referred to as High Definition Surveying ((HDS)), 3D Imaging, Terrestrial Scanning, and LIDAR) of the stilling basin slab and baffle blocks before and after demolition and following concrete placement to establish quantities for payment for demolition and placement of new concrete. Obtain the necessary permits to perform the work cited above. As a minimum, a permit from the Centre County Conservation District, will be required. For more details see the photographs and drawing below. The attached photographs and drawing are for information only. Please use the drawings issued with the solicitation for construction.

Division 02 -	Existing Conditions, Subsurface Investigation.
Division 31 -	Earthwork, Site Clearing, Grading, Excavation and Fill, Subgrade Preparation, Excavation, Shoring, Tunneling and Mining, Tunnel Excavation.
Division 35 -	Waterway and Marine Construction, Dam Construction and Equipment.