Tender Details
Pinotage Wetland Rehabilitation Project (Landscaping)
Tender Number:
MWP2210TX_OLD
Client:
Eskom
Region:
Gauteng
Industry:
Civil
Title:
Pinotage Wetland Rehabilitation Project (Landscaping)
Closing Date:
26/10/2023 09:59
Site Inspection Date:
N/A
Tender Description:
Office Location Pinotage Substation - Western Cape Email Address manakamt@eskom.co.za Scope Details The overarching concept for rehabilitation of the target wetland areas on the Pinotage site is to reinstate dispersed flow to these areas and to re-vegetate them with appropriate locally indigenous plant species (Appendix B) (Figure 7) Pinotage_rehab-report_draftfinal_24April2023 WdF Final_minpub. This is to be achieved by implementing the following broad steps, which are explained in more detail in the subsections below • Filling in of the existing dams and cut-off drains on the site, which are severely impacting water flows. • Creation of a series of very shallow (0.5 m deep) swales across the slopes, which will drain towards a central, very shallow dished channel running down the slope on each side of the substation towards the wetland area. • Dissipation and attenuation of flows through the placement of packed rocks at the outlets of the swales and dished channels. • Reduction of existing weed load through a series of site preparation steps. • Collection, propagation and storage of seeds and plant material. • Hydro-seeding and planting of vegetation in the target wetland areas, in the swales and dished channels and in the surrounding terrestrial areas, to facilitate attenuation of flows and reduction of weeds on the site. • Follow-up monitoring, weed control and supplementary planting over at least five years. It is anticipated that the proper implementation of these steps will result in reinstatement of more natural runoff patterns on the slopes adjacent to the substation, the creation of seep wetland areas with three zones of wetness (seasonally inundated, seasonally saturated and temporarily saturated zones), and the re-introduction of a diversity of naturally-occurring plant species (in the wetland rehabilitation target areas and surrounding terrestrial buffer areas) so as to improve the habitat quality and ecological functionality of the on-site wetlands. In order to achieve these outcomes, the required conditions need to be established, including the re-introduction of an ecologically appropriate suite of plant species, many of which are not commercially available, thus requiring propagation in a nursery. Also, the target wetland areas cannot be successfully rehabilitated into an ecologically functional ecosystem without rehabilitation of the adjacent terrestrial buffer area on the slopes above the wetland areas. It is akin to the human body, where the main veins cannot function without the capillary veins. As such, re-vegetation of the adjacent terrestrial buffer areas with ecologically appropriate plant species is as important as the re-vegetation of the wetland areas themselves, especially bearing in mind that the flows to the wetland areas need to disperse and filter through the upslope terrestrial buffer areas. Tender box address Retail Centre Megawatt Park 2 Maxwell Drive Sunninghill 2000 Description Pinotage Wetland Rehabilitation Project (Landscaping) Summary Pinotage Wetland Rehabilitation Project (Landscaping)