RSPB Crook of Baldoon Lagoon Development

Tender description

This tender documentation relates to earthworks associated with the Crook of Baldoon Lagoon Development. Lot 1: RSPB Scotland has converted the Crook of Baldoon Reserve, which is restored farmland and willow crops, to wet grassland providing breeding grounds to a variety of species and increasing the richness of other wildlife. The Crook of Baldoon is a key place of passage, wintering and breeding for wildfowl and waders within Southwest Scotland and a large number will utilise the reserve’s wetland and saltmarsh habitats. The site location is shown on Drawing No. 155977/9201. Within Field 7 and Field 8 of the Crook of Baldoon Reserve, RSPB intend to construct two lagoons, five islands within these lagoons, two scrapes, two sluices and outlet valve, a pedestrian bridge and a bund protecting the lagoons, with the purpose of these works to enhance the area for breeding birds. There is a series of land drains present throughout Fields 7 and 8, these will be required to be broken by trenching and back filled with as-dug arisings. In addition, stockproof fencing is specified around the field perimeter. The works will include the lowering of the existing ground level in order to create lagoons and shallow scrapes, the water level of which will be controlled by the sluices that will be constructed as part of these works. Within the lagoons, areas of fill are proposed to create low lying islands. The general arrangement of the site is shown on Drawing No.155977/9202. The purpose of the works is to undertake the following: 1. Topsoil strip over all areas of construction activity; 2. Breaking of land drains via trenches and backfilling; 3. Installation of two sluice gates and butterfly valve to control water level in the lagoon; 4. Earthworks are required to form lagoon and island features as well as bund formation; 5. Installation of timber footbridge over an existing burn; and 6. Replacement / installation of stock fencing. 155977 RSPB Crook of Baldoon Lagoon Development Contract Document 18 The earthworks will result in a surplus cut being generated. The surplus cut should be placed and sealed to create screening bunds at additional locations within wider site to be agreed with the Client. Potential locations of spoil disposal are provided within the Earthworks Specification (Appendix 1). An item for the removal of these soils from site has been included within the activity schedule in case a use cannot be determined. (See document for further details)