Southland District Council

CON 24-31 Stewart Island wastewater treatment plant desludging

The Stewart Island wastewater treatment plant consists of three (3) ponds, all of which contain high levels of sludge. Sludge removal is now required to improve the treatment quality of the plant.

Sludge shall be dewatered via geobags and shall drain back to Pond 1 under gravity.

The principal has confirmed that all sludge removed from the ponds shall remain on Stewart Island and shall not be transported across Foveaux Straight.

Southland District Council seek proposals from contractors who are suitably experienced with wastewater sludge removal and dewatering, can clearly demonstrate their ability to work in sensitive ecological environments, within the constraints of the site, in particular the remoteness of Stewart Island.

Innovation is a must; a desludging options memo and tender design and specification has been completed by our consultant, which is included in this RFT. Tenderers are required to confirm the design in preparation of their tender or provide an alternative tender.

The principal is seeking a contractor who will:
• be innovative; Stewart Island is a remote location with unique challenges that are not generally encountered on the mainland, including but not limited to:
o site is within an outstanding natural feature/landscape.
o access to site is limited, i.e. by sea, Island infrastructure may limit the size and type of equipment required to complete the works.
o constrained site, bound by native vegetation, limited laydown area available
• provide value for money; be cost-effective, complete the full scope of works within the available budget.
• plan and undertake the contract works in a responsible manner; be cognisant of working in the sensitive Stewart Island environment (sludge shall remain on Stewart Island)
• implement proactive strategies to enable the timely completion of the contract works.

Tenderers shall clearly demonstrate in their proposals that they understand the requirements of the tender documents, can promote their innovation to achieve the desired outcome and have the requisite skills, competency and resources to successfully complete the contract works to meet the principal's requirements.