Section 38 Rewetting Works by bunding, balance- pipe and dam installation

Tender description

Summary of the S38 rewetting project Fenn's NNR Section 38, Reeves' Fields, is in the West Midlands near Whitchurch and Wrexham. It is situated towards the southeastern perimeter of the internationally important Fenn's, Whixall, Bettisfield, Wem and Cadney Mosses Site of Special Scientific Interest (S.S.S.I.), in the Fenn's, Whixall & Bettisfield Mosses National Nature Reserve (N.N.R.). The Marches Mosses BogLIFE Project (LIFE15NAT/UK/000786) terminated in March 2023, and now unfinished works are being tackled using Nature for Conservation peatland Grant Scheme funding. The BogLIFE Project aimed to allow better control of water levels to enable wetland habitat to be restored on land which has been converted from peatland to peaty fields. Reeves's fields used to be peatland, and originally formed part of the south-eastern edge of Whixall Moss. In 2009 the Whixall Manor Drain, which was taking polluted and mineral-rich water up from local Cottages onto and across the centre of the NNR, was diverted nearer to the edge of the Moss but ended at a new culvert under the track leading north from Roundthorn Bridge, Whixall. The downstream 195m of the Diversion was left in the existing channel, with the intention to complete the diversion by excavating a new channel farther south during the BogLIFE Project. This last part of the Diversion has just been executed, so now the peat in the fields can be rewetted. Overall, this Scheme will rewet at least 4.25ha of deeper peats in Section 38 plus support water levels in adjacent Whixall Moss to the north. This Scheme involves: 1. Restoring the natural flow of water from north to south on Section 38. This will be achieved by using 2.65ha of 51 no.ca 20 x 20 m and 30 x 30m. cell bunding plus U-shaped cells ( ca 2490m) to bring water levels to within 10 cm of the peat surface for more than 70% of the year, permitting Sphagnum bogmoss or lagg vegetation to establish or spread and to outcompete grassland plants on the S.38 fields. 2. Installation of a new 50m-long feeder ditch, 5 peat dams and 13 balance-/ U- pipes to raise peat water levels on the bunding areas shown, and 48 short balance-/U- pipes to control within-cell water levels 3. Restoration of any damage to peat tracks. 4. Supply CDM information, production of As-built report and electronic location records/shapefiles for bunds, pipes and dams NE will supply all materials, which will need to be collected from the nearby Manor House NNR Base. The contractor will need a tracked excavator and one tracked dumper. It is anticipated that this contract will be awarded for a period of 4 weeks to end no later than 21/3/25, unless there is substantial disruption from adverse weather. Additional information: To apply for this opportunity you must submit your quotation meeting the requirements detailed in the Request for Quotation (RFQ) attached. Your response must be sent to joan.daniels@naturalengland.org.uk copied to peter.bowyer@naturalengland.org.uk by 09:00 on 16/12/24. If you have any clarification questions linked to this opportunity or the procurement process please submit these via email to joan.daniels@naturalengland.org.uk or Nathan.brake@naturalengland.org.uk by 11 December 2024 at 10:00am . Please note that, unless commercially sensitive, both the question and the response will be circulated to all tenderers.