Tender: Removal of Buckenbowra River Weir near Batemans Bay

About

Contractor needed to demolish and appropriately dispose of a failing weir on the Buckenbowra River near Batemans Bay. The weir is approximately 1 metre high and comprises two rows of sheet metal piling core, loose rock filling, gabion basket scour protection and a concrete capping; a concrete and aluminium fishway is present on the western side adjacent to drop boards that can be used to lower water levels before works begin. An engineering assessment obtained by the Principal will determine whether weir abutments must be removed or may remain and be made safe; unless abutments are retained, all weir components should be removed and disposed of appropriately. The structure has deteriorated with downstream scouring exposing sheet metal piling and loss/deterioration of gabion rock baskets. After removal, upstream sediment must be regraded to meet downstream river bed levels on a low gradient to prevent erosion. The site is accessible via Quart Pot Road on the eastern side; the western side is not accessible. The intended approach includes establishing erosion and sediment controls, slowly lowering weir pool levels by sequential removal of drop boards, working from the western bank back to the eastern bank to remove weir components, then regrading the river bed across the weir location.