Addressing trunk main losses with combined technologies

Finding leaks on transmission pipes and trunk mains can be especially challenging and with water utilities on the lookout for emerging technologies to address this issue, a satellite leak detection project in Africa shows there are solutions to this complex problem, as Jonathan Jacobi, director of sales, Utilis explains.

Supply interruptions and water losses from leaks on transmission pipes and trunk mains can be some of the most challenging water utilities face due to the large diameter of the pipes and the materials of which they are made. However, a satellite leak detection technology is helping address this complex issue, making finding the leaks much easier.

Drinking water pipelines are one of the sector’s largest and most expensive capital assets and maintaining their integrity must be a key priority. To achieve this, the reduction of water losses is a strategically necessity.

In October 2019, a pilot project was carried out on more than 1,000km of transmission mains in the south of Africa using Utilis’ satellite-borne L-band synthetic-aperture radar (SAR) analytics. Points of interest on the vast trunk main network were narrowed down using the technology, then specialist acoustic leak detection equipment from Swiss water loss technology company Gutermann was used to verify them and pinpoint leaks.

SARS image with pipe layers overlayed

While traditional leak detection techniques and instruments are less suitable for surveying large stretch of large-diameter pipes in rural terrain, Utilis’ technology is agnostic to pipe size or material, identifying leaks via soil moisture created by portable water mixing with the surrounding earth. The technology’s ability to pre-localise a leak, especially in such as difficult landscape, allows the surveying team to invest the time and equipment needed to pinpoint leaks, helping raise their efficiency and meet key performance indicators (KPIs).

Through random sampling, a total of 30 locations were identified for site investigation and verification in this project. This was followed by a leak validation exercise to mark the location and confirm the presence of a leak using Gutermann’s Aquascan TM2 trunk main leak correlator. This correlator is specialised in analysing the leak noise on large-diameter pipes and over distances of up to and sometimes even more than 1km distance. When the pipe distance and properties are known, the correlator is able to pinpoint the leak accurately.

The leak detection teams were able to locate leaks at all 30 locations, exhibiting 100% accuracy for the SAR technology and evidencing an effective job carried out by the teams in the field.

Likely leak location under investigation

Wake-up call
The need to protect water supplies by finding and fixing leaks as quickly and robustly as possible has never been more urgent, and not just in Africa. According to the World Resources Institute, demand for water has increased by 600% worldwide over the past 100 years and water utilities face increasing challenges due to aging infrastructure and vast networks spanning both urban and rural environments.

Satellite-based intelligence uses sensors to find leaks

Utilis’ remote-sensing technology uses a sensor mounted on a satellite orbiting at 637km above earth, which means it can capture an entire network in one shot. It has the potential to capture thousands of leaks using an algorithm that identifies the signature of drinking water escaping into the ground.

The expansive satellite-analytics helps companies strategically identify hot spots to investigate further so that leaks can be targeted before surfacing, reducing potential damage to nearby infrastructure and the environment.

This is particularly useful in rural areas as it is traditionally harder and more time-consuming detecting leaks in remote locations. In addition, the approach is non-invasive, can be frequently updated and is scalable.

“Fixing leaks is not just about stopping water loss once we are already aware there is an issue, it is also vital to pre-empt problems and prevent further collateral damage to the infrastructure and environment,” said Uri Gutermann, CEO of Gutermann. “There are solutions available to alleviate the pressure on water supplies and by harnessing technology and data to make intelligent, long-term decisions, utilities are better placed to address the growing problem.”

Cutting costs and water loss
Satellite leak detection offer utilities lower operating costs, with no preparations or upfront investments required. Leaks can be located faster, resources can be managed more efficiently, and background losses reduced, all resulting in decreased water losses.

Since developing the technology in 2016, Utilis has worked on over 250 projects worldwide in countries including the US, UK, Italy, Chile, China and Africa, leading to more than 30,000 leaks verified saving customers around 19,000 million litres a year.

Most countries are facing unprecedented pressure on water resources, and with global population growth, estimates show with current practices the world will face a 40% shortfall between forecast demand and available supply of water by as early as 2030.

To strengthen water security against this backdrop of increasing demand and water scarcity, the sector needs to invest in institutional strengthening, information management, and infrastructure development.

In the coming years, there is going to be a much higher demand for technology and data to address these pressing issues. The world is digitising, and the water industry must continue to adapt quickly and use these advances in technology to their benefit.

The message for water companies trying to address leakage is while the current solutions that exist may not be enough in isolation, when used in combination, companies can address leakage in a more efficient, cost effective and environmentally sustainable manner.