1 Basin Caisson - Cofferdam, Masonry Repairs, Installation

Tender description

Proposed to replace the existing caisson to 1 Basin. Proposed works to be undertaken as per the design and surveys approved with Historic England and Crown Estates. For full list of Civils work required see section II.2.4 for full information. Lot 1: Proposed to replace the existing caisson to 1 Basin. Proposed works to be undertaken as per the design and surveys approved with Historic England and Crown Estates. Install perimeter CPNI fencing to secure the site for the duration of the project. Installation of temporary cofferdams to the East and West that will not impact the historic fabric. Dewater and inspect and survey the 1 Basin stonework. Monitor historic seawalls and ground water levels during the works. Undertake stone wall repairs in accordance with Historic England detail specification and approval. Replace the penstock gate with electric operated replacement with civil works and electrical supply required to operate. Demolition and removal of the existing caisson constructure to 1 Basin. Repairs to the caisson groove and prepare for replacement caisson arrival (by others) removal all structural supports. Remove and survey the condition of the road bridge. Repair works to the sill and stone repairs to match the existing structure to the detailed specifications to Historic England specification. Install a temporary foot bridge during the project. Refurbishment and load testing of fairleads and bollards and leave in full working order for ongoing operations. Clean, survey and remedial repairs to historic brickwork culvert after dewatering. Remove the temporary cofferdams and refit road bridge after caisson has been replaced and all works to the bridge has been completed.