MAHIA Beach property owners will learn in the next two months what their community wastewater scheme will cost them.
For most households, the cost will fall somewhere between $10,000 and $14,500, says Wairoa District Council engineering manager Neil Cook.
Councillors last week approved a cost-allocation model aimed at balancing ratepayer needs, commercial interests and future demand.
The $11.8 million project is receiving $5.5m in government subsidy, up from initial funding of $3.3m.
“Without the subsidy, the project would not have gone ahead,” Mr Cook said. “The cost to individual ratepayers would have been too high.”
As it is, council finance staff are working on ways to minimise the impact on householders.
“People will be given the option of paying off their share in one lump sum or in instalments as part of their rates bill,” Mr Cook said.
“It’s a fairly heavy administrative task for our finance people. They are working on different time-frames for repayments and are even looking at whether it is feasible to allow people to pay the interest and not the capital, as long as the debt is the first thing paid when their house is sold.”
The Mahia wastewater project is a “decentralised scheme” known as a STEP (septic tank effluent pumping) system.
“In a traditional municipal system, your household pipe meets a gravity-fed sewer under the road and everything you flush gets washed away to a treatment plant,” Mr Cook said.
“I call it flush-and-forget.
“But in this system, we have on-lot primary treatment that settles out all the solids in a tank on the site. Clear liquid — the effluent — gets pumped in smaller, pressurised pipes to a treatment facility.”
Light commercial properties had been assessed as contributing no more than residential properties in terms of flow and they were allocated subsidy on the same basis as households, Mr Cook said.
Where a residential property had no house on it, subsidy would cover nearly all that property’s share of public infrastructure costs.
But when a house was put on that property, the owner would face on-lot costs of $6000 to $12,000, depending on the site requirements.
No subsidy was allocated to future connections on land that had yet to be classed as residential property, Mr Cook said.
That meant those putting a house on such a section would have to pay a connection fee of $12,200 plus on-lot costs of $6000 to $12,000.
The connection fee represented a portion of the costs of implementing the scheme . . . the community infrastructure — pipes in the road, the pump station, treatment ponds and disposal areas, Mr Cook said.
On-lot costs were the individual householder’s on-site septic tank and pumping equipment, and any on-site pipework.
No subsidy was allocated to properties in the Mahia Heights and Mahia Estates subdivisions, but they were slightly different to other non-subsidised connections.
Gravity-fed reticulation had been put in when these subdivisions were developed, and the scheme design took this into account. That brought connection costs there down to $13,500 a property.
Mr Cook said the scheme was designed to be able to take 619 residential connections. That allowed for 366 connections to existing households, along with connections to commercial properties, and enough capacity to handle the growth expected over the next 30 years.
Under the cost-allocation model, the council would keep aside $442,800 in holding costs for the estimated 131 available future connections. These connections were each valued at $12,200.
As new users were connected, the connection fees could either go into a reserve for future upkeep of the system, or be used initially to pay off the holding-cost loan and thereafter to build the reserve fund.
Mr Cook said the packs being delivered over the next two months would tell owners what needed to be done on their property, and the estimated cost.
Also included would be options for work the owner could do to save costs, options for payment, advice on how to “appeal” assessments, time-frames for action to trigger the subsidy, and a form the owner would need to sign to allow the council to apply for building consent and other regulatory approvals on the owner’s behalf.