1 - What is 'smart' water metering?
A 'smart' water meter is a mechanical meter that is fixed with a transmitter unit. The transmitter unit sends a wavelength pulse that is able to be captured by a receiver. The receiver can typically capture the signal within 50m-100m of its position. This will remove the requirement for a meter reader to open up meter boxes as well as allowing more frequent data collection. This will increase the efficiency of data capture while also reducing errors.
2 - How are properties chosen to have a meter?
The properties chosen to have meters cover a range of commercial/industrial, residential and absentee/holiday properties. Properties were chosen based on their locations within the water supply network and we have been in touch with these property owners to let them know about the project.
The properties were chosen based on:
- Commercial/Industrial/points of interest were chosen as key water users. This includes the majority of buildings within Tairua's Central Business District. Other properties such as schools and public facilities have also been identified.
- Residential properties were chosen based on their locations in regards to their water supply. This was over a range of properties in Tairua to ensure a good cross-sectional coverage was provided.
- Some absentee/holiday homes were chosen to capture data during the peak period.
3 - How often is data collected?
Regular data collections have been underway since the middle of 2014 and will continue on a less regular basis except during the peak period in order to monitor consumer usage over this time.
4-A petition from Marie Newton and signatories, however, noted that once the crowds left, and significant rain fell in Tairua, the restrictions continued far longer than seemed reasonable. Why?
Marie was close when she said she’d heard that the filtration plant has difficulty coping with muddy water. It can cope, but at that time, in addition to trying to replenish the water taken over the summer, during the rain, water was still going out faster than our plant could replace simply because it takes longer to clean the water to drinking standards after heavy rain.
The treatment plant is unable to treat water from its two sources during and directly after heavy rain events as the increases in turbidity have a significant effect on the treatment plant throughput. At times the turbidity can reach levels where the plant must be shut down until levels reduce. A number of these events have occurred in Tairua over the last two peak periods.
Once the water treatment plant is no longer providing adequate daily volumes to meet consumer demand, Council's network storage reservoir volumes decrease. The difficulty then is to restore the volumes in the reservoirs to adequate levels while still operating under the conditions of the Regional Council's resource consent limits. Currently reservoir capability in Tairua is adequate; however, the issue is being able to produce sufficient volumes of treated water, in excess of the daily demand, to prevent continuing loss in the reservoir levels.
A significant amount of leakage was identifited over the long period of water restrictions in early 2015 and, despite the rainfall over both the Christmas week peak and the New Year week peak, the system coped adequately.
5 - How can Council find and treat water leak issues?
Having every property on a water meter would make it much easier for us to see where leaks are occurring. However, without that, we are usually only able to see how much water is being used by a group of streets or properties. Still, even this method is more helpful than not metering at all because it helps us see if an area of town is, for instance, still using summer holiday volumes of water even after the summer holidaymakers have long gone.
Renewal of pipe assets are undertaken as required but as Tairua's system is generally younger than 35 years, scheduled repairs are fairly low. Reactive renewals are undertaken as required.
We’ve purchased trunk flow measuring devices and will be installing them in additional areas on our own network so we can track what’s going on as much as possible after this unusual extended restriction period.
6 - Which begs the question, how long must we remain on these restricted interim consents?
The long term resource consents have been granted and the consented abstraction volume, augmented by the construction of a new source of water (river banki filtration from Pepe Stream) which will be in place by the 2016-17 summer peak period, will alleviate many of the issues that necessitate water restrictions. It is, however, probable that short term restrictions will still be required.
Our draft Water Demand Management Strategy is also going to be important in solving this problem, given it’s more than just an issue with meters or consent takes, and community education on responsible use of the resource is significant.