FILTEC designs and builds innovative water treatment plant that helps Horowhenua DC win National Infrastructure Project of the Year Award
Story kindly reproduced from Local Government New Zealand Magazine
The groundbreaking Tokomaru water treatment plant upgrade resolved a major challenge for Horowhenua District Council and the residents of Tokomaru.
Awards judges hailed the winning scheme as outstanding, innovative and an example other councils across the country could follow. They also praised the strong contribution to public health outcomes.
The project sprang from the council’s search for a solution to providing Tokomaru residents with clean water. Water, sourced from the Tokomaru River and feeding the existing plant, had been assessed as carrying an unacceptable level of health risk to people drinking it. From 2009 to 2014 residents were advised to boil their water but, with the original project estimated at $2 to $3 million, they faced at least a JO-year wait for an upgrade.
Council staff continued to investigate solutions which would enable them to bring forward the upgrade so the plant was fully compliant with New Zealand Drinking Water Standards. Potential schemes investigated included installing under-bench cartridge filters to each property, installing UV filters out side each property or supplying water from a private bore. Slow sand filtration was also considered but was not feas ible due to the large amount of land required.
However, t hrough its ongoing investigations, the council eventually identified a possible alternative treatment and engaged Wellington-based FILTEC water and wastewater treatment specialists to install a pilot plant. Following a successful four-month trial and thorough assessment of cost and outcomes, the council – which worked with h2ope and Downer – agreed to press ahead with the innovative solution.
This involves the water being treated using chlorine disinfection, coarse sand filter, carbon filters, cartridge filtration and UV disinfection. Council officers had developed key relationships leading up to council approving the project and this ensured the project could get underway swiftly. Installation was completed just 102 days after council approval. The compact full-scale treatment plant was installed within a shipping container and the relatively modest project cost of just $350,000 – less than a sixth of the original estimate – meant there was a minimal impact on rates.
The project lifted Tokomaru’s water quality to become fully compliant with New Zealand Drinking Water Standards. LGNZ president Lawrence Yule said, “This is an excellent example of a council thinking innovatively, responding to community concerns and finding a solution that was affordable, timely and met community and Ministry of Health expectations.”