CH2M Beca is proud to work with the Gisborne District Council and the community to deliver Gisborne's new wastewater treatment plant.
CH2M Beca was engaged by Gisborne District Council (GDC) after it received a 35 year consent in September 2007 to discharge treated wastewater to Poverty Bay. The new consent required treatment via a biological trickling filter process, secondary clarification and UV disinfection. A new treatment plant was to be sited adjacent to Gisborne Airport, over 2km west of the existing milliscreening plant and ocean outfall. An industrial separation scheme for high strength seasonal food processing wastes was also included in the scope. All this needed to be achieved within three years of GDC awarding the design contract.
CH2M Beca’s first task involved a condition assessment of existing assets and characterisation of the municipal and industrial waste. After this initial phase, Beca completed preliminary design. For this stage, CH2M Beca project staff were located within the GDC office in Gisborne to ensure fluid communication and access between GDC and CH2M Beca resources.
The initial cost estimate at completion of preliminary design was well in excess of GDC’s budget expectations and affordability. The following phase saw CH2M Beca work closely with GDC and local community groups to provide options to reduce the total project cost to the region. During this stage, a new site within the Awapuni Industrial area became available for GDC to purchase. The new site was close to the existing outfall, which minimised transfer pumping. A staged construction plan was suggested, deferring clarification and UV disinfection until the performance of biological treatment could be monitored.
The revised scheme was submitted for re-consenting 12 months after CH2M Beca was engaged. The revised consent was granted but the plant still had to be commissioned by the original deadline of 31st December 2010. The revised scheme reduced the out-turn cost from $84M to $45M, which is a tribute to the collaborative efforts of CH2M Beca and GDC.
CH2M Beca provided contract administration and construction monitoring services, and the plant was commissioned before 31st December 2010.