River regulation and flood control works. Floodgates. Flood-prevention works. In December 2013 the Suffolk coast suffered the most significant sea-surge generated flood event since 1953. Large parts of central Lowestoft were flooded by seawater, the majority of which came from overtopping of low parts of harbour quay walls in the outer harbour and Lake Lothing water areas. WDC has secured funding to manage the risk of an early repeat flooding event by use of temporary, fully removable flood barriers.

In December 2013 the Suffolk coast suffered the most significant sea-surge generated flood event since 1953. Large parts of central Lowestoft were flooded by seawater, the majority of which came from overtopping of low parts of harbour quay walls in the outer harbour and Lake Lothing water areas. Backflow through sewers was also thought to have contributed.

As a result of this event WDC, working closely with partners in promoting a scheme to build a permanent tidal flood barrier that would protect at-risk land from a recurrence. This scheme is advancing and is anticipated to be in place within 5 years.

Pending completion of these works, WDC has secured funding to manage the risk of an early repeat flooding event by use of temporary fully, removable flood barriers.

As part of this process pre procurement market engagement occurred to assist the Council of their future requirement for temporary fully removable flood barriers. The market engagement documentation is included in this ITB which is for information only (PROC 153 Appendix 1) and is to ensure all bidders in the procurement process are treated equally.

The preliminary temporary flood barrier locations and alignments, plus existing ground levels, are shown on the drawings in PROC 153 Appendix 2.

The alignment is designed to generally locate the barrier onto a hard surface with vehicle access immediately adjacent to the deployment line. There are small steps, typically kerbs, pinch points at openings in barriers and numerous changes of direction. The line is split between public land, usually highway, and private land.

PROC 153 Appendix 3 comprises an annotated photographic ‘walk through’ with images that reveal surface type and potential obstructions to be negotiated.

PROC 153 Appendix 4 comprises long sections through the 4 preliminary barrier lines to illustrate ground level and target barrier height variations.

PROC 153 Appendix 5 shows the location from which photos in Appendix 3 have been taken.

The alignment may change under further risk analysis and during the development of an Operational Protocol. Neither will be available in time for this procurement process.

There are other interested parties namely landowners, and the Highway Authority, on whose land the barriers will be temporarily positioned and operated in response to a flood warning, and with whom WDC will need to agree an Operational Protocol. They will not be parties to the contract.

The back-flow of water through sewers and drains contributes to flooding of low land behind the harbour quay walls. This is being addressed in part by the fitting of back-flow control measures to 12 major sewer outfalls. This work by Anglian Water is underway and is predicted to be fully complete by April of 2016. This work will not address numerous other, usually small, diameter outfall pipes that have potential to create a flow path under the proposed barrier line. There is therefore potential for some drain-related flooding to take place in low areas landward of the temporary barriers. The Council is considering how to manage this risk.

An important element of this contract will be the Public Services (Social Value) Act 2012. This is a major contract for the Council and it will be a requirement for the Contractor (if any contract awarded) to consider how the Supplies or Services they provide might improve the economic, social and environmental well being of the area.

The anticipated contract value (if any awarded) for the Supply of Temporary Fully Removable Flood Barriers will be estimated at 300 000 GBP ex VAT. Any bid received higher then 300 000 GBP will be rejected as unaffordable. The Council reserves the right to amend any documentation throughout the procurement process, any changes made to the documentation will be declared through the Delta-esourcing.