Woodville Property Checks Locate Stormwater Problems

Door to door visits to check stormwater disposal in Woodville have revealed that when it rains heavily some properties have a problem.

Instead of flowing into the correct stormwater system, rainwater being diverted from the roof via the spouting and downpipes is ending up in the sewage gully traps. Property surface water can also cause problems.

Utilities manager Dave Watson said that fixing the problem could be easy. Redirecting downpipes from discharging into sewer gullies to soak holes or into the kerb and channel outlets at the roadside and also erecting raised surrounds around gullies would eliminate most issues.

Owners would be advised by letter of the faults at their residence and time would be given for repair work to be completed before the council paid a follow up visit.

Mr Watson said that in just three days of inspections council employees had located problems on 30 properties.

Staff had been aware of the issue through the council’s telemetry chart, which recorded a normal sewage flow of 15-17 litres a second on a dry day but leapt to

65-100 litres a second when it rained.

Now, with the completion of a $1.4 million upgrade to the town’s sewerage treatment plant to meet a resource consent the council is moving to remedy the current situation.

Mr Watson said this was very important because stormwater in the sewage system compromised the microbiological treatment in the oxidation ponds because of the dilution factor.

That meant that the cost of pumping, screening and UV processes became a lot higher because of the quantity that was treated. It also hindered the retention time in the ponds, which in turn would have an impact on the discharge quality.

The council also faces similar issues in Pongaroa and Ormondville.