Patch repair needed in new pipe

Streamlining CCTV Pipe Acceptance Testing

Streamlining CCTV Pipe Acceptance Testing

What is a pipe acceptance test?

Utilities that manage sewer and stormwater networks increasingly have reticulation pipework extensions constructed by contractors as part of developer works. These pipes are commissioned and adopted by the utility. In many cases, the new pipes are built as part of a larger development that incorporates road, footpath, and lot divisions for sale. It is important for public utilities to have assurance that these new pipe assets have been constructed to their approved design and are defect free prior to them taking ownership.

This inspection, or CCTV acceptance test, is a critical part of the process that confirms the newly constructed pipe meets the requirements set out by the relevant authority. A CCTV inspection for acceptance is intended to focus on a range of areas, including:

  • Surface damage of internal surfaces
  • Cracking, breaking, or holes in the pipe wall
  • Obstructions or deposits within the pipe
  • Constructed grade (fall) of the pipe
  • Deformation
  • Joint defects
  • Ponding of water, or flat sections
  • Connection and junctions
  • Length of constructed pipe

Public utilities usually specify that these inspections be completed to the relevant inspection reporting code and must meet minimum standards to be approved for contributed asset handover.

Patch repair needed in new pipe

Figure 1- Cured-in-place patch to rectify a pipe defect in a new pipe

Who completes and approves an acceptance test?

Civil construction companies are usually required to engage an independent CCTV sub-contractor to complete an acceptance test, with a qualified engineer providing sign-off on the CCTV results and other accompanying reports where required.

When does the acceptance test occur?

Utilities may be descriptive around what stage the acceptance test can occur, with practical completion of various other on-site works a pre-requirement. Where specified, this detail is listed in a specification document or instruction issued directly from the approving authority.

Cause of Delays

Delays in the workflow when submitting acceptance inspections can occur due to:

  • The time it takes to supply the approving authority the specified video and associated report/s; or
  • In instances where a pipe does not pass the acceptance test, there will likely be some form of minor repair/maintenance required and a follow-up CCTV inspection to confirm any identified issues have been rectified. In most cases this will be jetting to remove construction debris/deposits, or patching a location with pipe wall damage

If the follow-up to a failed CCTV acceptance test is delayed due to the workflow that is setup between civil contractor, CCTV contractor, and reviewing engineer; the cost to the overall project can be significant. In some cases, this delay will fall on the critical path of other finalization works and negatively impact other teams working on the development project. VAPAR has specifically designed a workflow that ensures the time between the CCTV inspection and approval is minimized to reduce any unnecessary or costly delays. In instances that repair or maintenance is required, the details of this can be distributed to the required parties quickly.

deposits and debris in pipe

Figure 2- Deposits and debris that requires removal before acceptance

How can VAPAR assist in avoiding costly delays in your review and approval timeline?

Same day turn-around can be achieved with upload from site that only requires the video file and an internet connection to your internet browser. VAPAR’s AI processing time is measured in minutes, not days. Your reviewed inspection results can be shared in real time with clients you have invited into the VAPAR.Solutions platform in a structured library of current and past inspection projects.

Alternatively, you can choose to send your package of inspection results for the day, or week, as a pdf report set or spreadsheet summary. What does this mean in practical terms? Data and results (including access to the selected inspection video files) can be shared without the requirement for downloaded software or file sharing programs. The CCTV inspection videos, and associated results are available directly to your client in the method most convenient for your situation.

Keeping all your inspections organised and accessible

VAPAR’s cloud storage solution for inspections means cataloguing, finding, and viewing your past CCTV results is both user friendly, and eliminates the requirement for on-premises storage. No more lost files spread across different servers and cluttered folder structures. For utilities that would like to compare original acceptance inspections with end of defect-liability inspection, or condition assessment years down the line, this can be done directly from your internet browser by searching asset ID, or node, to bring up your matching results.

Image of VAPAR.Solutions

Figure 3- Searching past inspections of the same pipe asset

About the Author Mark Lee
Road collapsed due to sewer failure

Things you need to know about sewer network maintenance

Things you need to know about sewer network maintenance

Are you having trouble getting approval for a routine inspection program for your sewer network? Here is some information to bolster your business case.

The Challenge

Councils and utilities are rarely in a position to inspect 100% of their sewer or stormwater networks. This means that careful selection is required when planning which pipes, manholes, and pits to inspect. This should involve risk-based decisions that often include a focus on high consequence of failure locations. However, risk is a combination of both consequence and likelihood of failure. For sewer networks, there is often a significantly increased likelihood of failure immediately downstream of sewer rising mains (pumped mains) due to sulphuric acid generation

What causes hydrogen sulphide corrosion in sewers?

Sulphate in sewage is converted to hydrogen sulphide (H2S) by bacteria present in the sediment/biofilm layer. The H2S can move from the liquid to gas phase which is often the cause of customer odour complaints. Sulphur oxidising bacteria (SOB) above the water level convert this gas to sulphuric acid which can be highly corrosive to the surface of concrete manholes and pipes.

Why are inspections necessary?

The cost and the associated impact of a partial or full failure of these assets can be significant. Understanding where these issues are likely to occur, the current condition of these assets, and the rate of condition change over time allows better management of risk and can save large reactive repair expenses.

What can I do about managing these assets?

Periodic inspection of the first few manholes downstream of rising main outlets and the receiving gravity pipework (especially if concrete/asbestos cement) is a prudent investment and recommended as a subset of your broader condition inspection programming. The image above is an example of proactive rehabilitation of two manholes just downstream of a rising main. This planned work is a fraction of the cost of dealing with a reactive repair after failure.

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