Space technology used to search for water on Mars is now hunting for invisible leaks under the streets of São Paulo, using satellites, AI, and chlorine signals to help Sabesp recover up to 6.7 billion liters of water.

A technology linked to space exploration has begun to be applied in urban supply networks, connecting satellites, artificial intelligence, and field teams in an operation aimed at identifying underground water losses.

A technology based on satellite radar and artificial intelligence, developed from applications related to the search for water in the subsurface of Mars and other planetary bodies, has begun to be used to locate invisible leaks in supply networks on Earth.

In Brazil, Asterra’s solution was contracted by Sabesp in a R$ 5.9 million agreement to map, over two years, the Metropolitan Region of São Paulo and guide field teams in identifying treated water losses.

The system uses synthetic aperture radar data, known by the acronym SAR, which can penetrate part of the surface cover and capture signals related to subsurface moisture.

The difference lies in the processing of this information: algorithms analyze the data obtained by satellite and look for patterns compatible with the presence of treated potable water, especially by the signature associated with the chlorine used in the supply.

The technology does not replace the work of teams on the streets.

It functions as a screening stage, reduces the search area, indicates priority points, and guides field investigation.

After the satellite points to a suspicious region, technicians use geophones, listening rods, and location apps to confirm if there is a leak and find the exact point of the problem.

Satellite technology emerged from the search for water on Mars

The technological base used by Asterra originates from applications aimed at identifying underground water on Mars and other planetary bodies.

According to the company itself, geophysicist Lauren Guy identified a possibility of adapting the method for Earth, where satellite data could be applied to monitoring water networks.

Utilis, the company that later began operating under the Asterra brand, was co-founded in 2013 to develop commercial uses of this technology.

From 2016, leak detection in underground water networks became one of the commercial applications of the system.

In practice, satellites in orbit capture information from extensive areas, and Asterra transforms this data into operational maps for sanitation companies.

The process allows identifying regions with signs of leakage, but confirmation still depends on trained teams and field equipment.

The radar used operates in the L band, a frequency range that can penetrate the ground and pass through elements like asphalt, vegetation, and surface structures.

The reading does not show a broken pipeline like in a common photograph.

What appears is a set of signals that, when processed, can indicate moisture compatible with treated water leakage.

How the satellite detects signs of treated water

The potable water distributed in cities undergoes chemical treatment before reaching homes.

One of the elements used in this process is chlorine.

The technology seeks to differentiate this water from other sources, such as natural soil moisture, groundwater, rivers, sewage, or rainwater.

The method combines remote sensing, database cross-referencing, and artificial intelligence.

First, the satellite collects information from the contracted area.

Then, algorithms analyze the electromagnetic signals and compare the results with the supply network layout provided by the sanitation company.

With this cross-referencing, the system generates a map with points of possible leakage near the pipelines.

The markings are classified by priority level, allowing field teams to focus verification on areas with the highest probability of actual loss, according to the tool’s parameters.

In the operation described by Sabesp, the indicated points can cover areas with a radius of about 100 meters.

Within this perimeter, geophonists walk the streets with acoustic equipment to listen for the characteristic noise of water escaping under pressure.

Geophones confirm leaks indicated by satellite

The traditional method of locating leaks depends on trained professionals to interpret sounds underground.

The geophone captures vibrations and amplifies noises produced by water as it exits the pipeline.

As the technician approaches the source of the leak, the sound tends to become more intense.

When there is suspicion, the team uses a listening rod to confirm the point.

In some cases, the ground is drilled to check for moisture presence.

If the rod comes out wet, the indication gains strength, and the location is forwarded for repair by the responsible teams.

Before the use of satellite solutions, these professionals already had different forms of screening.

Sanitation companies monitored pressure drops, out-of-pattern consumption, and noise sensors to reduce the investigated area.

Even so, many underground leaks do not reach the surface and may remain without visual identification.

Asterra’s technology comes into play at this stage.

Instead of focusing the search on very large areas, the system directs the investigation to regions where there are signs compatible with leakage.

According to Fábio Passos, loss manager at Sabesp interviewed by Superinteressante, the images are cross-referenced with the company’s water networks and displayed on maps with red and yellow markings, according to accuracy.

Sabesp Contract Targets Leaks in Greater São Paulo

Sabesp contracted the tool for use over two years in the Metropolitan Region of São Paulo.

The reported investment is R$ 5.9 million, with application in distribution networks and pipelines.

A report from Click Guarulhos, based on information attributed to the company, stated that in the first three months of operation, from April to June, the planned coverage included almost 9,000 kilometers of networks in São Paulo, Guarulhos, Osasco, and Carapicuíba.

These areas were included in the project due to a higher expectation of water volume recovery, according to the disclosed information.

In São Paulo’s capital, the technology was expected to reach regions such as Consolação, Avenida Paulista, Jardim América, Sacomã, Mooca, Guaianases, Itaquera, and Perus, in addition to the area of the Raposo Tavares Highway.

The expectation attributed to Sabesp was to recover 6.7 billion liters of water in the first 12 months of using the solution.

The volume was compared, in the disclosed information, to the supply of a city the size of Caieiras, in Greater São Paulo, with over 95,000 inhabitants.

In a previous test cited by Pesquisa Fapesp magazine, Sabesp analyzed 50 kilometers of networks in the Metropolitan Region of São Paulo.

Satellite images indicated 81 leaks, while traditional methods found 14 in the same context.

Engineer Cícero Mirabô Rocha, from the company’s Operational Development sector, told the publication that the exact location still depends on acoustic techniques.

Invisible Water Losses Challenge Sanitation Networks

Water losses are among the points monitored by sanitation companies in supply networks.

Part of them occurs due to fraud or measurement errors, while another portion is linked to non-visible leaks in buried pipelines.

When water does not surface on the street, the problem can remain undetected for long periods.

Superinteressante reported that Sabesp registers about 19% water losses in the 375 cities where it operates.

In this scenario, identifying leaks before they reach the surface allows for directing repairs, reducing waste, and preventing treated water from flowing away unaccounted for.

Asterra has already had the technology adopted in countries like China, United Arab Emirates, and Japan, as well as Brazilian cities like Rio de Janeiro and Curitiba.

The company does not own the satellites used in the process; its role is in interpreting the data, processing the images, and delivering the maps that guide water companies.

According to Fábio Passos, the accuracy of the solution used by Sabesp is above 90%, although the result depends on field conditions.

Heavy traffic, construction work, and urban noise can make it difficult to listen with geophones during the week.

At night and on weekends, less interference may favor the confirmation of points by the teams.

Use in sewage networks still depends on technical evaluation

In addition to potable water, Sabesp is considering applying the same type of technology to locate sewage leaks.

The logic would be similar, but it would require identifying other characteristic chemical compounds, as sewage does not have the same signature as treated water.

The possibility still depends on technical evaluation.

Sewage leaks can generate environmental impacts, especially when they reach soil, rivers, or drainage networks.

Therefore, early detection is also among the areas of interest for companies responsible for urban sanitation.

In current use, the most established application of the technology is in identifying treated water.

The satellite does not repair the pipes, does not replace the geophonist, and does not eliminate the need for network maintenance.

Its function is to indicate where the team should look first, shortening the path between the invisible leak and the repair.

A tool associated with the investigation of water beyond Earth now helps locate losses under streets, avenues, and sidewalks.