What are we doing?
Three waters renewals
This is a package of work addressing known network problems within in each council area in the region.
This is generally because an asset has reached the end of its design life; such as pipes that are past their use-by date or have been given a low condition grade so are likely to not be functioning efficiently and may fail if not replaced.
With this work we are:
- Trialing a faster, more efficient way of doing things and increasing the use of pipe lining (so we don’t need to dig trenches)
- Reducing the risk of faults and failures by renewing or replacing pipes
- Reducing the public health and environmental risks of wastewater network overflows
Most critical assets assessment
We have completed the first phase of assessing the current state of our most critical assets and follow-ups are now continuing.
Our most critical assets are the pipes, pump stations, reservoirs and treatment plants that we simply can’t afford to lose – the heart, kidneys and major arteries of the network. If they failed, there would be a major, unacceptable impact on the community and the environment.
This category includes about 450 kilometres of pipes, 79 pump stations, 139 reservoirs and water and wastewater treatment plants.
Pump station inspections like the one shown here are part of our most critical assets assessment.
This is about 10 percent of all three waters assets. We are not ignoring the rest of our assets, but these are our priority for assessment and maintenance or renewal. While we already know a lot about some of these assets, and something about the rest of them, we have been drawing information together into a health assessment for each asset. A health assessment determines the following information
- Future maintenance programmes
- Future condition assessment programmes
- An updated renewal programme
- Risk analysis
- Whether urgent repair or replacement works are required.
Where necessary, we have undertaken investigations to gather more information to inform the health assessments.
Pipe inspections are continuing across the region. While we had largely completed an initial assessment of these assets by June 2021, we are adding to our knowledge base with physical inspections. This will help us minimise the risk of pipe failures by having up to date information about their condition.
It’ll take time to complete physical inspections of all the pipes we want to look at, because most of them are constantly in use.
We will be using a number of methods including closed circuit television (CCTV) technology which involves driving a small robotic camera through the pipes and filming the condition of the pipes from the inside.
We will be flushing pipes to remove debris before we do the inspection. Sometimes, if there is an existing blockage in the pipe, this can result in wastewater coming back up the line. Fortunately, this is very rare, but if it does happen, we’ll let you know and help you fix it.
We will also be checking pipes that are under pressure by installing testing equipment on valves and hydrants. In some cases, we will need a small hole or trench to access the pipe, known as potholing. We will do this carefully, to avoid any impact on the network or your services.
This picture shows a CCTV robotic camera preparing to inspect a pipe.
Pump stations, reservoirs and treatment plants
We already hold a lot of information on the condition of these most critical assets. There are gaps in information on some pump stations and these have been inspected. Health assessments will be provided to councils as they are completed.
All this work is being delivered through the Very High Criticality Asset Health Assessment Project.