High-resolution sonar proves invaluable in search and recovery

The Yorkshire and the Humber Underwater Search and Marine Unit is using the latest high-resolution sonar technology in search and recovery operations.

The SeaKing Hammerhead sonar from Tritech International was recently deployed in South Yorkshire at Snailsden Reservoir in the Peak District where it enabled the team to quickly locate the body of a missing person who was believed drowned. Before the operation, the area was mapped using Tritech’s StarFish 990F, a high-resolution side-scan sonar system, to ensure the safety of divers entering the waterway and ultimately reducing the time spent in the water.

The sonar provides 360-degree scans of the search area. A geo-referenced plotter display and a built-in compass ensure accurate marking and mapping of the search area. It can be operated in two frequencies; 675 kHz for large area survey, up to a radius of 100m and 935 kHz for high-definition target examination at up to 40m radius.

Sergeant Steve Birss, of the Yorkshire and the Humber Police marine unit, explained: “In our role we are required to locate missing persons quickly and safely, often in nil-visibility conditions. The use of this equipment enables us to search larger areas in less time and then quickly guide the diver directly to the missing person. Using this equipment at Snailsden Reservoir reduced the search from weeks to hours, ultimately providing closure for the family concerned.”

He added: “In addition, Tritech’s generosity when we were engaged in very high-profile searches in York, North Yorkshire, proved invaluable. A SeaKing Hammerhead was provided for our use at short notice; a StarFish 990F was also brought to the scene by a member of the Tritech team who offered to operate the equipment on our behalf in adverse weather conditions for many hours.”

The Yorkshire and the Humber marine unit also visit schools to educate young children on the dangers of playing in open water.

The unit is made up of a dedicated team of one police sergeant and nine specially-trained police officers who deliver the service on a full-time basis to all four police forces of Yorkshire and the Humber.

It was launched in September 2012 when it was agreed by the four forces that it would be based in Humberside and would be established to maintain force capabilities at a time when significant budget reductions were required.

It was anticipated that the new unit would save in the region of £400,000 a year, money that the forces have been reinvesting into protecting local frontline resources.