Objectives

The primary objective of this tender is to appoint a qualified contractor to install a pond liner and carry out repair works at the wetland pond within the Pretoria National Botanical Garden. The project aims to restore the functionality of the pond, which has been compromised due to previous damage and interference, ensuring it operates effectively for ecological and aesthetic purposes.

Scope

The scope of work includes, but is not limited to:

• Design, repair, and installation of a pond liner system, including reshaping and regrading the pond to match existing slopes.
• Removal and stockpiling of existing rocks and debris, followed by reinstatement in a similar arrangement.
• Earthworks such as excavation, compaction, and preparation of the pond base to specified standards.
• Installation of a high-density polyethylene (HDPE) geomembrane liner, welded on-site to ensure a continuous, sealed surface.
• Construction of a composite decking system, including dismantling and reassembly of existing structures, and replacement of damaged planks.
• Rock pitching and landscaping around the pond perimeter, including stockpiling and reinstatement of rocks.
• Provision of site facilities, safety measures, waste management, and environmental protection during construction.
• Compliance with all relevant standards, specifications, and environmental and safety regulations.

Technical Requirements

The technical requirements for the tender include:

• Design & Construction: The works must adhere to SANS standards, including the use of CSIR and SABS approved materials. The pond must be shaped at a 1V:3.5H slope, with reshaping width of approximately 3 meters from the crest.
• Pond Liner System: Installation of a 1.5mm mono textured HDPE geomembrane liner, welded on-site with quality assurance testing (including peel and shear strength tests) in accordance with GRI-GM13 (2021) standards.
• Earthworks: Excavation, compaction to 95% PROCTOR density, and earth filling with selected insitu materials.
• Reinstatement & Repair: Dismantling and reassembly of existing decking, rock arrangements, and addressing wrinkles or defects in the liner.
• Quality Assurance & Testing: Regular non-destructive and destructive seam testing, sampling, and independent verification to ensure liner integrity.
• Environmental & Safety Compliance: Strict adherence to environmental specifications, waste management, site rehabilitation, and occupational health and safety regulations, including the appointment of competent safety personnel.
• Site Management: Demarcation of the construction area, minimal disturbance, and proper waste disposal, with measures to protect fauna, flora, archaeological sites, and prevent pollution.
• Documentation & Certification: Submission of health and safety plans, environmental management plans, and proof of compliance (e.g., CIDB registration, insurance, and permits) prior to commencement.