Water Pipeline Inspections

Water Pipeline Inspections


“When the well’s dry, we know the worth of water.”
– Benjamin Franklin

As one of the fastest growing economies, development of modern public infrastructure including underground water and sewerage supply network is on rapid growth in India. With rapid growth of urban infrastructure, most of these pipelines are laid underground, making it difficult to inspect by regular/standard methods. The problem is compounded with the fact that most of this network is now old (especially in Tier 1&2 cities) and requires immediate attention if we want it to continue to serve the rapidly growing population of our cities. Since manual entry and accessibility is limited, robotic methods of inspection, mapping and fault detection are the only means of maintaining the vast infrastructure of our water network.

Common Problems Faced

  • Most pipe installations are done with a minimum service life expectation. This service life can range from anywhere between 30-50 yrs.
  • However, seldom do these figures turn out to be accurate and regular inspection data is required to access the Remaining Useful Life (RUL) of these pipes.
  • Another problem faced is that often the exact location of these pipes in unknown. The problem is further compounded due to the rapid growth in surface infrastructure and non-recorded modifications made to the network over time.
  • Detection of existing leaks and their location remains the single most important requirement of municipal corporations.

Advantages of Robotic Inspection

  • Robotic Inspection methodologies eliminates the risk to human life
  • The data generated using such inspections can be integrated with existing GIS data of the ULB which helps in future asset management.
  • The generated inspection reports can be used as a reference to plan any future regular maintenance activities.
  • Robotic Inspection Tools can also be used to detect leaks inside these pipes and hence reduce NRW.
  • Old & running pipelines can be graded on a scale of 1-5 (as per internationally accepted WRc norms) which helps in establishing the pipe’s RUL (Remaining Useful Life).


The importance of trunk mains in the city water pipeline network cannot be over-exaggerated. Even where the supply is not 24×7, the trunk mains are still pressurized for the entire time since they are responsible for supply to different zones within the same network. Since we began operations almost a decade ago, DSI has been approached by several municipal bodies and consultants to develop a solution for trunk main inspection that can perform long range inspections of these pipes and provide real-time tangible data regarding their condition.

Further to their conditional assessment requirement, sometimes asset owners also need the exact alignment of their pipes as their as-built layouts are either not available or are not accurate.

In answer to these requirements, DSI developed a specially customized Long-Range Trunk Main Inspection Robot in 2019. The robot was deployed at the customer’s asset location and it was successfully able to perform conditional assessment inspections for their trunk mains for almost 1km from single entry point.


Besides inspection of existing assets, municipal bodies also require pre-commissioning surveys of the newly laid pipeline network to ascertain the quality of work done by the contractor. Besides, quality assessment, robotic inspections are also used to perform an intrusive inspection of the welding quality.

In most cases of new MS pipe installations, contractors are required to perform a radiography inspection of the welding quality after every set number of joints. The high cost and time associated with RT/UT inspections prevents their use for 100% of the installed network length. As a result, these checks become a more generic marker of the contractor’s install quality rather than a true QC method. On the other hand, robotic welding CCTV inspection can be used as redundant tool to assist the RT/UT inspection process. Its high speed and low-cost feature allow the contractor to perform a 100% robotic CCTV inspection of the weld quality from inside the pipe while the RT/UT inspections can still be performed for every set number of joints.