North West Regional Underwater Search and Marine Unit

Police work does not just happen on land – the North West Regional Underwater Search and Marine Unit undertakes crucial work above and below the surface.

The unit can be called out to search anywhere between North Wales and the Scottish Border.

The area covered includes the force areas of Greater Manchester Police, Merseyside, Cheshire, Lancashire, North Wales and Cumbria.

Established in 1978, the unit is highly experienced in search and recovery operations - as well as all maritime matters.

Based in Cheshire, Lancashire and Merseyside, the unit can handle incidents in any of the six force areas and covers the largest area of any police dive team in the UK.

They dive up to 50 metres deep searching for missing people, weapons, stolen goods and submerged vehicles, helping search the areas that other teams can’t reach, including:

• Lakes
• Rivers
• Marshland
• Ponds
• Canals
• Drains
• Up to 12 miles offshore in the sea


Divers often have little or no visibility in the water. To compensate for this the unit uses special searching techniques and items as small as .22 calibre ammunition have been recovered.

For their marine police activity they have a 42ft launch, rigid inflatable boats and a survey vessel.

The unit uses sonar technology helps the divers to see underwater. Sound waves hit objects in the water and once reflected back are interpreted as high-resolution computer images. The unit uses sonar to search for sunken vehicles, boats and missing persons.

The team are also equipped with a remotely operated vehicle (ROV).
The ROV is a small, unmanned submarine that is guided from the shore or a boat. It’s equipped with lights and a video camera.

The ROV is operated from a control box complete with monitor which displays live video that can be recorded for evidence.

What makes the ROV special is that it can dive to depths of 150m - recovering items from places too dangerous for divers to operate in.

The unit undertakes a large number of tasks each year and is able to deploy anywhere in the region at short notice.