Innovation Challenges

Background & Current Practice

Singapore's water supply network comprises an extensive system of underground pipelines requiring regular maintenance to ensure uninterrupted water supply. The current leak repair methodology presents significant challenges as it is labour-intensive and affects public convenience.

Upon discovering a leak in the water pipeline network, the team in charge of repairs must follow a complex, multi-step procedure. The process begins with isolating and dewatering the affected pipeline section, which temporarily disrupts water supply to the surrounding area. Teams must then excavate the road or soil to reach the underground pipeline—a particularly demanding task in Singapore's densely developed urban landscape.

Repairs typically involve either fitting external repair clamps or replacing leaking pipe sections completely. Subsequently, the site requires careful backfilling and road surface restoration to its original state. This process is not only resource-intensive and expensive but also causes prolonged disruption to water supply and traffic flow.

In Singapore's context, where urban density is high and underground space increasingly congested, the current repair methods present substantial logistical challenges. The situation demands innovative solutions to minimise excavation requirements, shorten repair times and reduce potential disruption to both water supply and urban activities.

Current Technology Status

Current repair methods require full isolation, dewatering, and excavation to replace damaged pipe sections. For leaks caused by small holes, clamping the pipe is another common repair method that does not require a shutdown but still requires excavation at the leak location. However, there are currently no widely adopted solutions for in-situ repairs under pressure, limiting the ability to conduct repairs without water supply interruption or major excavation.

Areas of opportunity

We are seeking innovative solutions for internal pipe repairs that are deployable through existing network access points or via minimal keyhole excavations, thereby minimising service disruption. These access points may include hydrants, air valves and access manholes.

The proposed solution must effectively repair pipe leaks whilst maintaining the network's structural integrity and water quality standards. To ensure minimal customer impact, the solution should also allow repairs to be carried out with little to no water supply interruption, with any necessary shutdown kept to within 2 hours to facilitate the repair works.

Successful implementation will revolutionize PUB's water supply network maintenance by substantially reducing reliance on traditional open-cut repairs. This approach will yield significant cost savings through reduced excavation and reinstatement works, whilst minimizing traffic disruption and impact on businesses and residents.

Background, Current Practice and Areas of Opportunity

3D printing represents a transformative technology that could address key challenges in operational resilience and efficiency for water utilities. While 3D printing has revolutionised aerospace, defence, and medical sectors, its game-changing applications in water infrastructure remain largely untapped.

Our water infrastructure demands constant vigilance and maintenance to ensure uninterrupted service delivery. A critical challenge we face is maintaining a resilient supply chain that can provide reliable access to spare parts for our water infrastructure. While our in-house inventory management system serves us well, we see opportunities for improvement. When unexpected equipment failures occur or components deteriorate prematurely, the traditional supply chain can face delays in delivering urgent replacement parts. 3D printing offers an opportunity to develop on-demand, rapid manufacturing capabilities for critical components to minimise operational disruptions.

Furthermore, we see opportunities to use 3D printing to produce smart equipment or components that can improve our operations. We envision transformative possibilities in how we monitor and maintain our infrastructure. Imagine 3D printed pipe fittings that can also detect pressure anomalies, 3D printed sensors that can be printed on demand, 3D printed wearables for personnel health and safety monitoring or 3D printed rotating elements/components with embedded sensors. These enhanced components could enhance our approach, allowing for customisation and parts to be printed in-house in future.

The integration of 3D printing into PUB's operational and maintenance strategies will enable rapid response to potential risks, minimise downtime and reduce dependence on external supply chains. We seek partners with proven expertise and experience in 3D printing who can collaborate with us to develop practical solutions for our water utility operations. From manufacturing replacement components to smart equipment, we are interested in exploring several potential novel applications that aligns with our goal of strengthening operational resilience and efficiency.

The core capabilities we aim to develop include:

1. Creating accurate digital models of components through 3D scanning technology, establishing a reliable digital inventory of critical parts.
2. Implementing 3D printing systems that deliver consistent, high-quality components while optimising production times and costs.
3. Developing expertise in materials science and post-processing methods to ensure printed components meet the rigorous demands of water utility applications.

Background & Current Practice

Desalination plants in Singapore utilise GRP pipelines extensively in their water treatment processes, primarily due to their corrosion resistance properties. These pipelines, ranging from 150mm to 2,400 mm in diameter, play a crucial role in the desalination process by transferring both seawater and treated water between different treatment stages to accommodate various flow requirements. However, GRP pipelines are susceptible to premature deterioration when exposed to prolonged sunlight and poor lamination workmanship during installation.

Desalination plants face significant operational challenges when the pipelines fail, with repairs requiring a minimum of 24 hours due the time needed to cure the laminations. Early detection of weak spots and joints is crucial for preventing GRP pipe failures and ensuring the continued efficient operation of desalination plants. While PUB has established capabilities for leak detection and condition assessment of metal and concrete pipelines, there remains a specific need to explore cost-effective technologies in GRP pipeline assessment.

Addressing this challenge within the next few years is crucial to reduce unforeseen pipeline failure, which may become more frequent due to ageing assets. The current situation threatens plant operations through rising operational costs, and the risk of emergency shutdowns. Implementation of preventive measures would safeguard the plant's ability to meet its water supply commitments.

Areas of Opportunity 

1. Non-invasive and non-destructive methods (e.g., ultrasonic testing, thermography and radiography) to inspect pipelines externally, combined with instrumentation, drones or robotic platforms to enable safe access to hard-to-reach areas.
2. Methods capable of remote inspection, such as acoustic testing and transient pressure monitoring.
3. Methods that allow large area inspections from a distance given the large quantity of GRP pipelines in desalination plant, preferably those enabling inspection of elevated pipelines without requiring scaffolding or Mobile Elevated Work Platforms.
4. While external inspection methods are preferred, solutions may include in-line inspection method, provided they do not compromise water quality.

1. Safeguarding of plant operations by prevention of catastrophic failures.
2. Decreased operational costs by optimising maintenance schedules and reducing emergency repairs.
3. Improved safety by preventing hazardous pipe failures and reducing the work at height needed to inspect pipelines.
4. Improved plant reliability by ensuring consistent water supply.
5. Extended lifespan of GRP pipeline infrastructure by more accurately identifying area of weakness thereby delaying the need for costly replacements.