The Chest: Willow Park Reservoir Upstream Slope Protection

St. Helens Council own and operate certain reservoirs and have a statutory duty under the Reservoirs Act 1975 to manage and maintain them. Willow Park Reservoir holds more than 25,000 cubic metres and is designated by the Environment Agency as high risk because an uncontrolled release of water could put people’s lives at risk.

The Council engage an Inspecting Engineer who identified that protection works are required and will certify they have been carried out. The protection works are carried out using Open Stone Asphalt which is a bituminous mix of single sized crushed stone coated with sand mastic.

After installation and a light compaction sufficient voids remain for it to be permeable to water and air. A layer of Lean Sand Asphalt may also be required as a filter/regulating layer and a consistent surface for the Open Stone Asphalt.

This Invitation to Tender (ITT) is issued to organisations with an interest in the provision of the works described. Each organisation is referred to as “the bidder”.

The main remedial works include:- [1] Remove vegetation, soil, debris and silt; [2] Remove loose pitching and protection blocks; [3] Clean existing pitching blocks and replace missing joint material; [4] Lay new or re-used pitching blocks; [5] Lay open stone asphalt as new slope protection Associated works are included to the siphon drawdown inlet and pipe; and the service overflow structure:- [A1] The siphon drawdown inlet and pipe is known to silt up and the Contractor may have to clear these and maintain them during the works; [A2] When the water level is lowered the service overflow structure can be inspected to see if additional work is needed to maintain it. This should be treated as a confined space.

The bid is a single open tender process evaluated as 70% price:30% quality. Bidders complete and submit the The Qualification Questionnaire and the Invitation to Tender documents as their submission.

The Tender Evidence Document The Council is exercising its right to obtain further evidence and will invite the most economically advantageous bidder as a prospective supplier to submit a TED. A copy is included with the bid documents but does not need to be completed until you are asked but please read it to ensure you can complete.

Prospective suppliers may still be excluded if their TED response is late, incomplete or otherwise unacceptable and St Helens reserves the right to invite other bidders should a prospective supplier’s TED be excluded. Dates Last date to submit questions about the ITT: 17:00 on Thursday 4 August 2016 Return of bids: 16:00 on Tuesday 10 August 2016