Last week The News revealed work had begun on land on the outskirts of town, near the golf course, which Ngāi Tahu plans to develop into nearly 200 residential sections.
Central Otago District Council Three Waters group manager Julie Muir said upgrades to the water treatment plant and the Alexandra reservoirs meant there was enough capacity to meet the town’s growth projections for the next 30 years.
However, there would be some constraints in some parts of the pipe network, and projects to resolve that were part of the draft 10-year plan.
On the other hand, wastewater — sewerage and stormwater — was limited by the wastewater treatment plant, which was already in need of a significant upgrade, Ms Muir said.
Presently there was only one processing line, so the plant could not be offline for renewal or work for more than eight hours. As the plant aged there would be increasing need for work which would take it offline for longer.
Investigations into providing enough capacity for the next three decades of growth had thrown up two options — one costing $100million and the other $40million.
Changes to government water legislation and policies and the proposed Otago land and water plan would affect which option could be advanced and how long it would take, she said.
The upgrade would be part of the long-term plan to be consulted on early next year.
"In the interim we believe there is sufficient capacity within the existing plant to meet growth needs for land zoned for residential development under Plan Change 19 for the next 10 years, provided stormwater inflow into the network is reduced."
However, the ratepayers would not have to foot the entire bill for the infrastructure needed for the proposed development, Ms Muir said.
Developers were required to pay development contributions for every section, which helped fund increasing the capacity of existing infrastructure to meet the growth. The council then programmed the upgrades to happen when they were needed.
The timing of when the infrastructure growth was needed was driven by when houses were ready to be connected to the water systems.
There was often several years between consent being granted for a development and all the sections being built on.
The council’s water staff were working more closely with developers to better understand when houses would be built to make sure there was no problems, Ms Muir said.
The application for subdivision for the Ngāi Tahu land was on hold at their request.