Police and Dive Companies Using Sidescan Sonar
A wide variety of users including public safety dive teams and commercial dive companies are finding sidescan sonar to be an essential piece of equipment in their search and survey operations. Sidescan sonar is a tool for these projects because it produces detailed images of the underwater environment regardless of water clarity. It scans several hundred feet of ocean, lake or river bottom with each pass of the boat, allowing large areas to be searched quickly.
The sonar’s acoustic beam reflects off any objects lying on the bottom and the data is sent topside where vivid colour images are displayed and stored on a laptop or tablet computer. Sidescan can locate sunken boats, submerged vehicles and drowning victims as well as inspect bridge supports, seawalls and dams. Even in zero visibility the image quality can be almost photographic.
One agency utilising this sonar is the New York Department of Environmental Protection (DEP) Police. Members of this department are New York State police officers and they investigate more than 4,000 complaints each year including illegal transportation, storage and disposal of hazardous waste. To assist in these investigations, the DEP Police acquired a JW Fishers SSS-600K sidescan sonar. The sonar allows them to survey reservoirs to ensure no foreign objects are contaminating the city’s water supply (image). The department recently upgraded their sonar system and sent two officers to Fishers facility in Massachusetts for a free day of factory training.
Another law enforcement agency using the sidescan is the Dubai Police in the United Arab Emirates. This desert kingdom located between Saudi Arabia and Oman is small by geographic standards, but holds the world’s 7th largest oil reserves and is one of the wealthiest countries in the Middle East. The 15,000-strong police force is responsible for the safety and security of 2 million people. The police coordinate all emergency responses as well as search and rescue operations on land and sea. For water SAR operations the department acquired a JW Fishers sidescan sonar with splash-proof computer and Sonar Map Coverage software. The computer with ultra-bright display allows the sonar to be operated from small, open boats. The mapping software shows the operator the track of the boat as it moves over the search area as well as the width of the area being scanned, to ensure no piece is missed. Fishers also offers an adjustable transducer option for the sonar which allows vertical structures to be scanned by rotating the angle of the transducers. This means a team can survey the face of a dam, seawall, pier, bridge support, or ship’s hull to look for damage or any ‘unnatural’ device like an explosive that may have been attached to a submerged structure.
Hydromax in the Philippines are also employing these sonar, providing its customers with an extensive list of underwater services including ship maintenance and repair, hydrographic surveys, pier inspection and repair, search and salvage, and dredging. They are equipped with tools and equipment including JW Fishers SSS-600K/1200K sidescan sonar with 200 metres of cable and CMS cable management system. The 600K allows an area up to 150 metres wide to be scanned with each pass of the vessel. When very high-resolution images of an underwater object are required, the sonar operator simply switches to 1200K with a click of the mouse. It will be instrumental for pipeline surveys and salvage projects.
