Objectives

The primary objective of the Emergency Groundwater Supply Project – Knysna is to refurbish and rehabilitate existing groundwater boreholes to ensure a sustainable and reliable water supply for the municipality. This includes cleaning, drilling, reaming, casing, borehole development, disinfection, water quality testing, and sustainable yield testing of eight prioritized boreholes, with the possibility of considering additional boreholes based on refurbishment outcomes.

Scope

The scope encompasses:

• Refurbishment and rehabilitation of existing production boreholes, including cleaning, borehole reaming, casing, camera inspections, and borehole development.
• Drilling of new boreholes if refurbishment is not feasible.
• Fishing, camera inspections, and sustainable yield testing (step tests, constant discharge tests, recovery tests).
• Water quality analysis and disinfection of boreholes.
• Environmental management and site rehabilitation post-works.
• Provision of temporary works, site facilities, and management meetings.
• Implementation of labour-intensive construction methods prioritizing local labour.

Technical Requirements

The technical scope includes:

• Refurbishment of non-operational boreholes, including cleaning and re-drilling as necessary.
• Fishing and camera inspections to identify blockages and assess borehole integrity.
• Sustainable yield testing through step tests, 48-hour constant discharge tests, and recovery monitoring.
• Drilling techniques suitable for various geological formations, including rotary air percussion, Odex/Symetrix air percussion, reaming, and rehabilitation.
• Use of casing, perforated casing, screens, and borehole development methods.
• Water quality sampling and microbiological testing aligned with SANS 241 standards.
• Design and implementation of borehole headworks, casing installation, and disinfection procedures.
• Environmental management measures to minimize ecological impact, including site rehabilitation and waste disposal.

Skills Requirements

The contractor must demonstrate:

• Extensive experience in groundwater borehole drilling, rehabilitation, and testing, with a minimum of 15 years relevant experience.
• Proven capability to drill boreholes to depths exceeding 300 meters.
• Capability to undertake borehole rehabilitation, fishing, camera inspections, and sustainable yield testing.
• Qualified personnel including drilling supervisors, borehole technicians, health and safety officers, and environmental specialists with relevant qualifications and experience.
• Ability to provide and operate specialized drilling equipment, including multiple rigs capable of drilling to 300 meters depth.
• Experience in environmental management, site rehabilitation, and compliance with health and safety regulations.
• Capacity to manage logistics, environmental protocols, and community engagement effectively.