Wai Taatari Construction to Begin Soon

Preparation has begun on a major upgrade of the New Plymouth Wastewater Treatment Plant.

The Wai Taatari (‘filtered water’) project will see the plant’s two existing aeration basins modified to be more efficient, enabling them to meet the district’s needs for nearly 30 years.

Contractors have begun establishing themselves on-site, and construction is due to start in the middle of June.

“Essentially, we’re replacing the aeration system with equipment that looks like upside-down shower heads, which will be attached to the bottom of the basins,” says Manager Projects Mark Hall.

“These will release oxygen into the wastewater. This diffuser system is 40 per cent more efficient than the surface system we have now and is designed to meet our needs until 2040 – at which point we’ll probably build a third aeration basin.”

The workers will start on constructing a blower building for the equipment that forces oxygen through the system.

In mid-October one aeration basin will be taken off-line for the equipment to be installed. It will be in use again in the New Year, after which the second basin will be worked on.

The $11.5 million project is scheduled to be completed by the end of August next year.

“The aeration basins are the heart of the wastewater treatment process,” says Mark Hall. “By making them more efficient, we’re making it possible to treat wastewater to a higher standard and also treat a higher volume in coming years.”

The NPWWTP was built in 1984. Major modifications over the years have included construction of a third clarifier and the thermal drying facility, and improvements to the milliscreen process.