What the new WSA 05-2020 changes mean for you

What the new WSA 05-2020 changes mean for you

Get excited people, the new WSA 05-2020 version has arrived! 

WSAA announced on their website on August 12th that the Version 4.1 is available and will now supersede WSA 05-2013, Version 3.1.

I’ve actually been eagerly awaiting this new version to release for quite some time. A large part of my eagerness was because VAPAR took part in the final drafting of code during the public consultation period back in October 2019 – so I was keen to see what the outcomes were and what feedback was incorporated.

I’ve reviewed it and completed a side-by-side comparison with my 2013 copy to spot the differences. As a self confessed pipe nerd, I couldn’t help myself. 

Overall, it was an interesting read. If you want to jump straight to the impact of changes skip ahead to ‘What are the impacts of these changes?’. If you want more technical detail, read on.

The good news is that overall, WSA 05-2020 looks to be a win for asset owners – at least in the long-term.

Changes affecting condition assessment

The new version of the code has introduced some changes which will impact condition assessment, both from a structural and service point of view:

  • Lateral (connection or junction) defect scores will now be scored separate to the main conduit condition score.
  • A number of defect categories will now be reporting both as a structural AND service defect compared to the previous version where the majority of defects were considered EITHER a structural or service score (e.g. displaced joints, deformation etc.)
  • A number of defects have been added to the code (e.g. lifting hole damage for stormwater conduits)
  • A number of defects have additional characterisations and quantifications added (e.g. greater quantification of % cross sectional area reduction for service defects).
  • The scoring numbers for defects have been updated. On average, the scoring values have been decreased for structural defects and increased for service defects compared with the previous version.

What else has changed?

  • Inclusion of an acceptance inspection specification for newly constructed gravity sewers and stormwater pipes
  • Appendix A is much more comprehensive on software requirements
  • This version will be delivered via e-book delivery, not print

What is the impact of the changes to WSA 05?

The good news is that overall, WSA 05-2020 looks to be a win for asset owners – at least in the long-term.

Separating the grading of lateral and main conduit defects will provide improvements in the segmentation and granularity of data. This means greater decision-making power for asset owners because more information about your assets will be captured during inspections – always a good thing! It also means that asset owners can be sure that main conduit condition scores will no longer be escalated by issues that are related to property owner connections.

Here’s the catch – this is going to cause some headaches in the short-term. Right now, the market simply isn’t set up to record this distinction between lateral and main codes, meaning that we’re going to have data issues until we have the chance to make up some ground.

Similarly, adding defects, characterisations and quantifications helps with gathering granularity on asset condition (as above, yay for better decision making!). 

However, the question needs to be asked – is it actually realistic to expect that all these codes will be used correctly and consistently? Almost 200 additional defect categories have been added into this version of the code, representing almost a 50% increase in the number of categories that need to be learned and coded by field operators and auditors. Whilst, the majority of these additional categories are in fact the ‘characterisations’ and ‘quantifications’ of the main defect codes, the reality of implementing these additions meaningfully will still be very challenging.

One of the criticisms of previous versions of the WSA code is that it grades ‘too harshly’, resulting in asset owners needing to spend more time on further qualification and/or prioritisation in an effort to reduce their backlogs. The good news is that this version of the code has made some headway in addressing this. Structural defect scoring values in the 2020 version of the code have on average been decreased as compared to the 2013 version. With most (but not all) organisations using structural condition as an indicator for repairs, this general decrease in scoring values for this category may result in fewer assets being unnecessarily escalated to rehabilitation programs.

‘Structural defect scoring values in the 2020 version of the code have on average been decreased as compared to the 2013 version.’

Do the new WSA 05 changes affect my organisation?

WSA 05 is used Australia-wide as an inspection and reporting guide. But it has much farther reaching implications on the industry than just providing a standardised method to survey pipes. The condition gradings that come out of the inspection process go on to inform millions of dollars of CAPEX and OPEX budgets for years to come. In fact, the 1 (good) to 5 (failed) ratings are more akin to accounting standards than engineering ones. For this reason, it is important to be aware that this re-definition of scoring can present an opportunity (or challenge!) to your bottom line that relates to renewal backlog and future work.


It was encouraging to learn that the public consultation period for this version was very involved and I think the overall result is something that achieves the WSA 05 documents purpose – to provide a uniform standard coding system for recording and comparing defects. For me, the committee has done a good job in addressing the challenges from the previous version. The changes represent an overall win for asset owners, but not without presenting some challenges for the industry. But who doesn’t love a good challenge?


About the author

Amanda Siqueira is an Australian civil and environmental engineer who has worked in design, construction and remediation of drainage and sewer pipes in Australia, New Zealand and the UK for almost 10 years. She has passion for all things pipes and is also one of the co-founders of VAPAR.

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