Smoke testing of the wastewater pipe network started in Hokitika on Tuesday 26 October 2021 and will take approximately 6 weeks to complete, until approximately 14 December 2021.
It must be noted that these times are approximate and will depend on weather, the size of the property, and progress with other work occurring at the same time.
Residents should not be concerned if they see smoke coming from the pipe network.
Six catchment areas in Hokitika have been identified as requiring smoke testing.
The decision as to which catchment is to be tested is been based on the age of particular networks and total funds available.
Catchment areas are shown in the map below.
The catchment areas, together with dates and actual physical location, are listed here.
|
Catchment Area 2 |
Covering the area bounded more or less by Gibson Quay and Hampden Street and Brittan St and Town Belt East. |
15 days from the 12/10/2021 to 2/11/2021 |
|
Catchment Area 3 |
Covering the area bounded more or less by Gibson Quay and Hampden Street and Brittan St and Fitzherbert St. |
6 days from the 3/11/2021 to 10/11/2021 |
|
Catchment Area 5 |
Covering the area bounded more or less by Hampden St and Airport Dr and Sale St and Alpine View (but not including Alpine View). |
6 days from the 11/11/2021 to 18/11/2021 |
|
Catchment Area 7 |
Covering the area bounded more or less by Revell and Fitzherbert Streets and Hampden and Richards Streets. |
10 days from the 19/11/2021 to 2/12/2021 |
|
Catchment Area 8 |
Covering the area bounded more or less by Revell / Beach and Fitzherbert Streets and Hampden and Weld Streets. |
5 days from the 3/12/2021 to 9/12/2021 |
|
Catchment Area 9 |
Covering the area bounded more or less by Beach and Fitzherbert Streets and Weld Street and Gibson Quay. |
3 days from the 10/12/2021 to 14/12/2021 |
A letter drop to all properties in the area will take place one to two weeks prior to testing.
Areas affected
What is smoke testing?
Smoke testing involves injecting a dense, non-toxic and odourless smoke into the wastewater network, and then watching to see where the smoke escapes. It's normal for smoke to come out of the sewer vent pipes on roofs of homes and buildings, this doesn't indicate a problem. However, if smoke emerges from storm drains or rises from lawns, pavements or the street, this indicates that there is a problem such as a cracked wastewater pipe, damaged manhole or a cross-connection to the stormwater network.
The liquid used to create the smoke is based on demineralized water, and the substance that creates the white particles in the smoke is food or high grade glycols. The specific glycols used are monopropylene glycol and triethylene glycol. These glycols are the type used in the “theatre” industry for the production of smoke and are not hazardous to health or the environment. It is important to note that the liquid is vaporized and not combusted to create the smoke effect.
If the smoke comes into your home, please open windows at each end of your house and the smoke will disappear in a few minutes. Smoke appearing in your home may indicate that there is a problem with the plumbing in your home. Please contact a licensed plumber to make any necessary repairs.
Why is smoke testing necessary?
The wastewater network is designed to collect wastewater from homes and business, not rainwater or groundwater. When rain or groundwater enters the wastewater network, it has the potential to overwhelm the capacity of the network (especially in heavy rain events). This results in overflows of diluted wastewater into our streams, rivers and harbours. This can have a harmful effect on our environment.