Red Wharf Bay Flood Alleviation Scheme

Description

A major flooding event occured in December 2013, and the smaller events in the 2013-2014 winter period saw flooding in Traeth Coch (Red Wharf Bay) not seen for many years. The coastal wall did little to prevent seawater inundating the properties along the frontage, with businesses and residential properties being flooded. The grassed area, and the coastal road were both also flooded, and in many places, the wall is breached by high tides and stormy weather on an almost annual basis. The Traeth Coch (Red Wharf Bay) Sea Defence Scheme will aim to protect the community from a 1 in 200-year coastal flooding event. Lot 1: Traeth Coch (Red Wharf Bay) Sea Defence Scheme Outline Description of Works 1. Introduction Following the flooding of local businesses and residential properties during Winter 2013, the Traeth Coch Sea Defence Scheme will aim to protect the community from a 1 in 200-year coastal flooding event. The site is located near a SAC/SSSI 2. The scheme is divided into 6 sections as detailed on the following Drawings: a. 6991/LP/1000 B 6991/GA/1001 – 1006 6991/GA/2001 – 2006 6991/DR/5000 Summary: Wall Type A – Contractor Designed 12m long 600mm high wall Wall Type B – Contractor Designed 132m long 1200 to 2300mm high wall Wall Type C – 360m long 1200mm to 1500mm high wall Pressure pointing – approximately 720m2 Excavation and concrete backfill to rear of wall – approximately 360m3 Slipway construction – 50m2 Flood Gates – 3 Number Steps to beach – TBC (Awaiting Confirmation from Client) b. Section 1 – Contractor designed approximately 12m long 600m high and approximately 22m long 1200mm high wall constructed within the tidal range, all stone clad including reinstatement, concrete jetty (50m2), and flood gate. Contractor to incorporate glass panels and all fixings into the geometric design of the proposed new retaining wall. All cast in-situ concrete works to be kept to a minimum. c. Section 2 – Contractor designed approximately 110m long 1900 - 2300mm high wall constructed within the tidal range, all stone clad including reinstatement and an 8m long Headwall within an existing watercourse. Contractor to incorporate glass panels and all fixings into the geometric design of the proposed new retaining wall and New Headwall. All cast in-situ concrete works to be kept to a minimum. d. Section 3 – Remove existing concrete capping, pressure pointing to seaward face of existing sea wall and build masonry wall 80m long 850 to 1200mm high on existing wall and excavate to rear of wall and fill with in-situ concrete including forming stepped access and supply and install flood gates. e. Section 4 - Remove existing concrete capping, pressure pointing to seaward face of existing sea wall and build masonry wall approximately 90m long, 1200mm high on existing wall and excavate to rear of wall and fill with in-situ concrete including forming stepped access and supply and install flood gates. f. Section 5 – Remove existing vehicle restraint system and build masonry wall approximately 70m long and 1500mm high and excavate to rear of wall and fill with in-situ concrete. g. Section 6 – Remove existing concrete capping, pressure pointing to seaward face of existing sea wall and build masonry wall approximately 120m long 1500mm high on existing wall and excavate to rear of wall and fill with in-situ concrete including forming stepped access and supply and install flood gates. 3. Form of Contract – NEC 4 Option A 4. Contract Dates – Mar 2022 to Mar 2023 5. Approximate Value - 1.5 to 2m