The carbon footprint of New Plymouth's wastewater treatment plant is set to be significantly reduced in the future.

A $37 million government investment, announced this week, will enable the replacement of New Plymouth's ageing thermal dryer with one which will run on a blend of hydrogen and natural gas supplied by New Plymouth-based Hiringa Energy.

The thermal dryer is a machine which turns wastewater into fertiliser. New Plymouth is the only wastewater operator in New Zealand that produces fertiliser and sells it commercially. Other plants which use a thermal dryer send the dried product to landfill or use it in their own parks, but don't sell it. The New Plymouth plant produces about 1600 tonnes of Bioboostâ„¢ each year from biosolids or sludge.

Since the old dryer was turned off in February, when it needed repairs which would cost over $1.5m, New Plymouth District Council has been sending the sludge by truck to Hampton Downs.


New Plymouth mayor Neil Holdom said the funding announcement was good for the district.

"New Plymouth is the only council that produces and sells fertiliser as a byproduct from treating our wastewater, avoiding the sludge going to landfill, protecting our stunning natural environment and generating some revenue from what would otherwise be a cost.

"We welcome the investment in a critical and ageing piece of infrastructure which will create a significant number of jobs for the very talented engineering sector in Taranaki who have time and time again proved our local expertise is on a par with anywhere in the world."

The news was also welcomed by Venture Taranaki CE Justine Gilliland.

"This project is another step in our region's journey to further build hydrogen as a key part of our energy mix, as New Zealand's energy province. It also furthers our transition to a low-emissions economy and helps further develop our region's skills and capabilities in this area, building on the significant and unique-to-New Zealand skills and deep knowledge our region already has."

The new thermal dryer will significantly reduce the carbon footprint of running the facility by cutting emissions by 25 to 40 per cent. The dryer will service 27,000 properties across the New Plymouth district.

Mayor Holdom said the investment is good for the community, the environment and for local businesses.

"We welcome the coalition Government's investment in our community in an initiative which is good for the environment, good for the engineering sector and just what our local economy needs right now as we recover from Covid-19.


"New Plymouth District Council appreciates the support of Infrastructure Minister Hon Shane Jones, Economic Development Minister Phil Twyford and Minister Hon Andrew Little who we know have all been instrumental in delivering this investment for the people of North Taranaki."