1. Why has the Leighton Avenue Catchment area been singled out for Council's private drains upgrading policy?
As a result of a renewed Resource Consent issued in 2004, Council is required to take action to reduce overflows of sewage into the Waiwhetu Stream by 2009. These overflows are caused during heavy rainfall, by groundwater getting into faulty public and private drains in the Leighton catchment. Other areas of the city may have similar requirements in the future as resource consents come up for renewal.
2. What has Council done to reduce the overflows?
To date Council has spent $3 million of a $5 million programme, which includes upgrading all public drains, installing additional wastewater storage facilities, conducted a trial upgrade of 70 private drains and completed testing of over 500 properties in area 1.
3. Why did Council conduct a trial?
A trial was undertaken to test whether upgrading private drains would be effective in reducing the amount of groundwater entering the system during heavy rainfall. The trial included 70 properties, a number considered to be representative of the wider catchment (containing approximately 2,300 properties). In the trial, peak flows were reduced by 70%. This gave Council confidence that the upgrading of private drains programme would be successful in reducing sewage pollution into the Waiwhetu Stream.
4. What does testing involve?
All properties within the catchment will be tested at Council's cost to determine the extent of the upgrading and repairs. Experience shows that about 70% of properties will need their drains repaired. The test takes half an hour.
The property owner does not need to be home (although we recognise that many owners will want to be present) and no digging on private property is required. If the Resource Consent conditions were not being met in future years, the area would be tested again.
5. How would the upgrade be undertaken and how would Council decide what repairs are needed?
Through a competitive tender process Council will have a number of different rates or costs per meter. These will include dig up and relay of drains, or repairing without digging up the drain by putting a machine into the drain. Council's engineering consultants; TCB will discuss and agree with each owner the best and most cost effective combination of methods for the particular property. The Council contractor or private drain layer will then complete the repairs to the agreed combination.
6. What is the situation if the private drain crosses the property boundary to the public drain located in a neighbour's property?
There will usually be no need to do any digging on a neighbour's property. But if there is a need to work on a neighbouring property, then there are legal rights that enable that work to be completed with or without the neighbour's consent. The property owner will be responsible for all repair costs from their house to the property boundary. Council will pay for upgrading the portion of drain from the property boundary to the public drain regardless of whether the main drain is located under the road or on private property.
7. Who pays if there are a number of properties sharing a common private drain?
The property owners will each pay an equal portion of the cost of repairing the shared common drain. They will also pay all the cost of upgrading their individual drains to the point where their drain joins the common drain. Property owners would also need to check their body corporate agreement, unit title or cross lease conditions.
8. What will it cost and what happens if I can't afford to pay?
The average price for upgrading private drains was $2,000 excluding GST during the trial it is expected that this would be the average cost for upgrading private drains in Leighton Avenue catchment. The situation will be the same as for non payment of rates. Ultimately the cost will become a charge on the property which can be recovered when the person moves out and the property is sold.
9. What are the owner's rights if a neighbour's trees damage their private drains?
It is the owner's responsibility to have drains on their property repaired. Property owners could take action under Section 129C of the Property Law Act to recover costs from a neighbour and, in some cases, have the offending tree removed. With regard to Council trees, if damage to private drains is solely caused by Council trees these will be assessed on a case-by-case basis.
If the entire drain is faulty, i.e. not only where the trees have caused cracks to the pipes and joints then the owner would pay for the upgrade as this would be required regardless of damage occurring due to tree roots from neighbouring properties.
10. What happens if my drains are upgraded and subsequently damaged by an earthquake?
EQC advise that private sewer drains are covered by insurance subject to certain conditions. The conditions are that the sewer is on the private property and it is no longer than 60meters from the dwelling. This means that as long as owners have adequate insurance they will be covered for earthquake damage. The material used for modern drains is not as susceptible to earthquake damage as the old ceramic pipes.
11. Will upgrading private drains in Leighton Avenue Catchment improve the flooding around the Waiwhetu Stream?
No. The flooding issue in this area is being addressed by a separate task force - The Waiwhetu Stream Advisory Committee, which is run by the Greater Wellington Regional Council.
12. Has infill housing made the private drains situation worse?
No. Overflows to the Waiwhetu Stream occur when groundwater gets into private drains during heavy rainfall. Flows increase by over 400% during wet weather. Usually drains of infill housing will be new and in good condition and so do not allow groundwater to enter the drain.
13. What are other Councils doing?
Both Upper Hutt and North Shore City Councils have adopted similar policies. Property owners in these two districts are responsible for arranging the upgrade work on faulty private drains at their own cost. North Shore, in particular, has had some success in reducing their wet weather flows after the policy was adopted.