The Tauranga City Council imposed water restrictions on the city in December for the first time in 17 years. Those restrictions are still in place. Photo / File
The Tauranga City Council imposed water restrictions on the city in December for the first time in 17 years. Those restrictions are still in place. Photo / File
An expert in resource management believes investment in sustainable solutions is needed when planning for Tauranga's future water use.
While Tauranga does not have a water supply shortage, there is an issue in its capacity to treat and deliver water over the hot summer months as the city grows.
Water restrictions were imposed in mid-December for the first time in 17 years for that reason.
Toi Ohomai Institute of Technology's associate professor in resource management Dr Ian McLean said the council should look at conservation and efficiency as the best mechanism to respond.
"The real options in terms of dealing with these issues are much more radical – they are redesigning our houses to do things like use water off the roof."
He said new houses should be built with water storage and the collected water should be used in toilets, bathrooms and in the garden.
"We're doing a massive amount of building right now in the city; none of those houses are having water storage built into them as part of the construction design. That is absolutely crazy."
Dr McLean said the implementation of water metering in Tauranga in 2000 initiated an increase in efficiencies and conservation, but that benefit had since been lost because of the increased number of houses.
"In Kapiti all new builds are required to have a water tank now. In Tauranga, it's 'no we don't need to do that because we have got lots of water'. And it's true, we do have lots of water, but we deliver processed water for people to flush down their toilets and water their lawns."
He said the city did not need to do that.
"As part of the city's growth, do you just go on and on investing in infrastructure or do you invest in efficiency? Efficiency is usually cheaper.
"It's totally predictable because climate change tells us we're going to have drought, it tells us we're going to have more extreme weather conditions, which means also we're going to have some heavier rainfalls. So why don't we get people storing water in their houses?"
Dr Ian McLean, associate professor in resource management at Toi Ohomai Institute of Technology. Photo / File
The council's water services team leader, Peter Bahrs, said long-term sustainability of the city's available water resource was at the core of the council's future planning.
"Even once the Waiari [water supply scheme] has boosted our treatment capacity we still need to view water as a limited resource and manage it efficiently. Our water supply streams are precious and we need to respect them."
Bahrs said water tanks certainly had their benefits and the council had previously looked at whether they could be a viable option in Tauranga.
"But like many things that seem obvious, it's not a simple solution. Any rainwater collected to use on gardens quickly runs out during periods of hot, dry weather. There's also the expense of plumbing them into your existing network should you wish to use them to flush toilets, which also creates potential public health issues through cross-connection with the city water supply."
He said there was also the ongoing expense of maintaining the tank and pumps that have been installed.
"That's not to say we've discounted water tanks entirely. We're currently re-investigating water tanks to see if they could make a difference to our water demand, as well as how they could potentially provide a water supply in the event of an emergency."
Bahrs said the findings of that investigation would be reported to the council's Environment Committee before June.
Tauranga's water restrictions still in place
•The Tauranga City Council imposed water restrictions in mid-December for the first time in 17 years. •The total ban on sprinklers and hosing down hard surfaces such as driveways and paths still stands. •People can still water their gardens by hand using a hose or watering can between 5am-8am and 7pm-10pm. •Before the restrictions, the city was reaching daily water use peaks of around 56 million litres. It is now tracking at below 45 million litres a day on average. •Tauranga's current limitation is treatment capacity, not raw water source. •The new Waiari treatment plant will extend the city's treatment capacity, but there will be a few more tight summers before it comes on line. •Seventeen years ago the council was supplying the city with the same amount of water as it is today, even with another 40,000 people living here. Source: Tauranga City Council
