Investigations – piecing together the damage – SCIRT
We can all see the earthquake damaged roads and bridges when we drive around the city. What we can’t see is what impact the earthquake has had under our roads. To ensure the most appropriate repair is designed, we need to understand the impact the earthquake had on our underground pipes. SCIRT uses a range of investigation techniques to get information about the condition of the underground infrastructure:
- Geotechnical investigations – to understand the ground condition and soil types
- CCTV (Closed Circuit Television) – to see inside the pipes under the ground
- Pipe profiling – to understand the change in gradient and flow of the pipes
These investigations provide information to our design teams who can then determine the most appropriate way to repair this damaged infrastructure.
Investigation work can be done in a relatively short timeframe. It typically takes somewhere between two days to two weeks to complete the investigations in a street, depending on the kind of damage that is found. When investigating the wastewater pipes the team may come across a blockage which takes a long time to clear and creates delays getting to the next street.
The equipment required for these investigations is highly specialised and it is moved from one investigation to the next. This makes the investigation programme very mobile and one team can be working in different parts of the city on any given day.
Combined with the short term nature of the work, the mobile style of operation makes it is particularly challenging to keep people informed about exactly when our teams are going to be working in each street. We use a number of different ways to let people know about these works, depending on a number of factors, such as urgency, type and duration of investigation. One of the notifications that you are likely to see around town are the onsite signage.
Investigations help us to piece together the damage caused by the earthquakes. They are a critical part of the design process and will inform SCIRT’s five year programme of work. While you might see investigation work happening next week, the repair of the infrastructure may not happen for a number of years – depending on how it is prioritised alongside the many other repairs needed around the city.
SCIRT’s website has some more details about these wastewater and storm water assessment techniques.