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In the third of our series of articles looking at what makes Greater Manchester Fire and Rescue Service ‘Outstanding,’ I met the team who are developing the use of sonar on sub-surface drones to aid water rescue. With some innovative thinking, deep passion and an organisation that encourages ideas, the service is early in its promising journey to use underwater sonar to enhance water rescue and keep firefighters safe along the way.
In Greater Manchester’s former docklands, now reborn as waterside leisure spaces, an old hazard has taken on a modern face. The canals and basins around Salford Quays look benign, but beneath the surface they are deep, dark and unforgiving. Drownings in inland waterways are now around three times higher than fire deaths in the UK. Faced with this reality, Greater Manchester Fire and Rescue Service (GMFRS) has turned to an innovative blend of sonar, robotics and open‑source engineering to transform how crews search for and recover submerged casualties.
The team is headed up by Dave Allsey, known to everyone in GMFRS as Stan, and the innovation is a compact, bright‑coloured underwater remotely operated vehicle known as a UROV. It has been in use since March and the team are clearly enthusiastic about the capability and its potential to vastly enhance water rescue.
Setting out the problem
Historically, GMFRS crews responding to drownings in the city’s still waters found the same circumstances: incidents were almost always witnessed, someone sees a person stumble or jump in, calls 999 and firefighters are mobilised. Stan describes the typical response:
“Despite the fact we saturate the area with surface rescuers using poles and the little mini cameras we’ve got on the water rescue units, we rarely find them. The diver comes along the next day from the police diving team, and they find them exactly where we were looking in as little as five feet of water. Even though we had 25 personnel on the water, we could do nothing because we can’t go subsurface.”
Drawing on past experience with sonar from scuba diving, Stan began exploring how to bring advanced sonar into frontline rescue in a cost effective way. That exploration has culminated in a system that combines high‑resolution imaging sonar with a manoeuvrable ROV capable of physically recovering a casualty.
Sonar as the star of the show
The 25kg UROV carries multiple sonar systems, but the core sensor is a multi-beam imaging sonar mounted on the vehicle’s nose. Rather than the single sweeping “ping” familiar from submarine films, this unit fires around 512 beams of sound, building a continuous, live image of the underwater environment. Dense objects show as bright returns; crucially, their shadows on the sonar display reveal their shape and size. Stan says that working with industry has been critical to bringing his ideas to life.
“We are hugely indebted to the team at Blueprint Subsea, who make the Oculus 750D sonar. It’s the star of the show really and we are grateful to them for the free loans of equipment they have provided so that we could develop this capability here in Greater Manchester.”
To train the team and get to know the capability of the UROV, they have studied every known drowning in Salford Quays. Each one has been recreated using a submersible dummy placed where real casualties were found and in each case, the sonar has located them immediately. This is a dramatic improvement on traditional, largely blind search methods. Even when the video camera is almost useless in murky water, the sonar can show a recognisable human outline: head, arms, legs and the tell‑tale shadow behind.
A second, side‑scan sonar mode allows the team to ‘slice’ through river channels, building a picture as the ROV moves forward; this has proven essential when the exact entry point is unknown or when someone has been swept away.
During my visit, the team had the UROV sitting on a metal deck next to a large pond at the training centre. With one of the team looking at the cameras on a laptop set in a ruggedised box and another member of the team on hand to place the UROV in the water, the work starts as the UROV is piloted from the safety of land and attached to a cable so that it can be returned to shore. It makes no noise and once in the water it glides through the water and speeds up on command making little impact on the surface as it does its work.
Stan calls the technology magic and kicks back when I call it a drone. “It’s not a drone, people keep calling it that, but it’s not. It’s a wired, remotely operated vehicle. We need that wire because that’s what’s going to pull them up. The technology is very simple: it’s two computers talking to each other, there’s a computer in the actual ROV, and there’s a computer in a box where we can see what it sees and navigate to where we want it to go.”
From oil and gas to open‑source rescue
Much of the technology suitable for this kind of work has been developed for the oil and gas industry, where a single ROV package can cost a quarter of a million pounds and needs to be shipped back to the supplier for maintenance.
Instead, GMFRS has adopted a cost-effective approach using what Stan calls an ‘enthusiast‑grade ‘ROV platform. They have invested in one from Blue Robotics in California, designed originally for scientific users and built around open‑source software. Working with search‑and‑rescue specialist Chris Beer from Sarsub, they specified, flat‑packed, built and integrated their own system. This comprises multi-beam sonar, high‑output lighting, video, manipulator arm and a Kevlar‑reinforced network tether capable of hauling more than a hundred kilos.
Because the vehicle is modular and familiar to its operators, most faults can be repaired back at the station in under an hour. The team has logged more than 300 dives so far, with the system continually tweaked and upgraded based on operational learning.
Engineering for survival time, not just recovery
The real innovation lies not only in finding bodies faster, but in shifting the focus back to potential survival. The team works to a ’30–60–90′ protocol informed by academic research into post‑drowning resuscitation. It shows that the colder, deeper and younger the casualty, the longer the possible window for successful resuscitation. In Manchester, where water temperatures are below six degrees for most of the year, that window can be significantly extended.
Fast, technology‑assisted recovery can also matter even when survival is unlikely. Stan explains that emergency physicians at Salford Royal Hospital have highlighted that drowning victims are often prime candidates for organ donation because they are young, fit and previously healthy. Prolonged immersion in dirty water can render organs unusable, so if the UROV can locate and retrieve a casualty within tens of minutes rather than many hours, it may turn an otherwise total loss into the chance to save multiple lives.
Putting robotics on the fire engine
The UROV packs into a single box and fits on a fire engine based at Salford, its location was chosen after analysing GMFRS’s water rescue data. Vehicle access around the Salford Quays means crews can arrive, deploy, boot the system and be scanning the water within minutes.
From a game‑controller‑style interface, operators can pilot the UROV like an underwater helicopter, using compass bearings to navigate, then switching to video and a manipulator arm that is fitted with dedicated hooks during real incidents to grab and haul in the casualty via the tether.
By fusing accessible robotics, open‑source engineering and advanced sonar into a deployable, repairable frontline tool, GMFRS has quietly pushed water rescue into a new era. In old dock areas that have turned into modern flats and leisure destinations, this innovation may be the difference between a body recovery and a life saved. Or, at the very least, between one tragic death and the possibility of saving several others.
Read the previous articles in this series – Why body worn video isn’t just for policing and our interview with Chief Fire Officer Dave Russel, When an emotionally intelligent leadership culture leads to outstanding performance.
The drones and robotics feature returns to The Emergency Tech Show in September. Register to attend here.
