Drinking Water for Seddon Water Treatment Plant


Marlborough District Council



$2.65 Million

Project type:
Safe Drinking Water

Plant Capacity:
7000 m3/day

Customer Need

Boil water notices was part of life if you lived in Seddon, a south Marlborough town in New Zealand. The water quality there was unsatisfactory as the town sources water from the Black Birch Stream where there is a presence of algae; during heavy rain flows, the water would turn cloudy and the old water treatment system could not cope with the runoff.

Furthermore, the Kaikoura earthquake allowed previous unseen organics to enter the water source causing significant taste and odour issues. With Seddon being in the earthquake zone, the town needed a new water treatment plant that is reliable and resilient to provide clean and safe drinking water.

What We Did

Filtec was contracted to design, supply and install a new water treatment plant (WTP) for Seddon to provide at least 700m3/day of drinking water, compliant with New Zealand Drinking Water Standards.

The WTP had a combination of processes such as pre-treatment, ultrafiltration membranes, TrojanUV advanced oxidation, chlorine gas dosing and so on to ensure the water meets New Zealand Drinking Water Standards. The advanced oxidation system was put in place to target taste and odour issues. It can be turned on and off for seasonal demand.

The Results

The water treatment plan was a huge milestone for Seddon. For the first time in decades, they have clean and safe drinking water straight from their taps. Furthermore, an emergency water supply was factored in to cope with reduced flow, meaning the town will still have clean water should another earthquake happen.