The Department of the Army, US Army Corps of Engineers, Portland District has a requirement to refurbish all Trashracks at the Bonneville Lock & Dam located at Rufus, Oregon.

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• The function of the trashracks is to prevent large debris from entering the intakes of the dam and damaging the turbines. The trashracks at the Bonneville Dam were originally installed in 1937 and are now 83 years old, and based on remote operated vehicle (ROV) inspections, most of the trashracks that can be seen, appear to be in reasonable shape. It is noted that these racks have likely experienced little in the way of loading and that the steel has not experienced any significant loading cycles. For the Bonneville Dam, 186 trashracks are anticipated needing refurbishment and/or complete replacement.
• The Bonneville Dam 1st Powerhouse has 10 main units and one (1) station service unit requiring repairs and/or new intake trashracks. Each main unit consist of three (3) slots, and each slot has six (6) racks – one (1) top and five (5) bottom racks. The station service unit has one (1) top rack, four (4) intermediate racks, and one (1) bottom rack. All trashracks will be refurbished as part of this contract for a total of 186 new racks. Debris removal is anticipated to occur as part of the scope of work to allow the lower trash racks to be replaced.
• The contractor shall rehabilitate and/or replace 186 trashracks at the Bonneville Lock & Dam. The Government is seeking the removal, media blasting, repair and/or replacement, and reinstallation of 186 trashracks, with 6 as fully fabricated spares. The trashracks range in size between 10 to 12 feet in height, 22 to 26 feet in width, each share similar details in welding and potential damage. Installation will be performed at scheduled intervals within the previously mentioned time frame.
• Installation will require the removal of existing trashracks and installation of new/refurbished trashracks with equipment, such as cranes, provided by the contractor. Government furnished equipment may not be available for trashrack installation. Installation will also require removal of trash and debris in front of the bottom trashracks prior to removing the existing racks. Contractors will need to provide divers to verify the sill is clear prior to installing the new bottom trashracks.
• It is anticipated that there will be four (4) levels of refurbishment that may be required. For estimating purposes, the following levels of refurbishment have been assumed:
  • Level 1: Good Condition (assume 60%) – Trash racks are in visibly good condition with no visible damage and minimal corrosion. These racks will be inspected, sandblasted, and painted.
  • Level 2: Moderate Condition (assume 34%) – Trash racks have minor damage and/or signs of more extensive corrosion. These racks will be inspected, sandblasted, repaired, and painted. Assume 10 trash bars are replaced.
  • Level 3: Fair Condition (assume 5%) – Trash racks have moderate damage and/or signs of more extensive corrosion. These racks will be inspected, sandblasted, repaired, and painted. Assume 20 trash bars are replaced with minor repairs to the frame, guide pins, or wear plates.
  • Level 4: Poor Condition (assume 1%) – Trash racks show significant damage and/or corrosion. Assume these are disposed of and replaced with new trash racks.