Search
And Recovery In The Marine Environment
Search
and rescue operations on land are in most cases fairly straightforward
especially with the help of helicopters, sniffer dogs and the ever-ready
public to lend a hand when searching for lost objects or bodies. According
to Michael Colley, Project Manager of Gardline Environmental Ltd 'Working
in the marine environment is very different'.
'When someone or an object falls into a river, the lives of many are
often put at risk to locate and recover the victim/object. There are
also a number of problems associated with working in the aquatic environment
i.e. poor visibility, choppy conditions, tidal currents, cold or freezing
temperatures and in certain areas contending with shipping or pleasure
boats which can greatly hamper delicate operations.
Using divers for search operations can take precious time especially
when the environment is in an area where one or more of the above problems
exist. Divers are also governed by health and safety procedures, which
would limit search times especially in areas where there is medium to
strong tidal currents and poor visibility.
The problem with tidal currents is if the object has been in the water
for some time and depending on its buoyancy rating it may not be anywhere
near where it was dropped or fell into the water. Poor visibility restricts
field of vision and usually “feeling the riverbed” is usually
the only way to find something even when using strong underwater lighting.
The way forward is to utilise the latest high-tech equipment used in
the marine survey industry, which will accelerate operations especially
during the searching process.
Initial
Search for Lost Objects or Drowned Victims
Using high tech equipment is a way forward to enable search and recovery
operations to be carried out in a safer manner and also significantly
speeds up the process of the actual search operation which can sometimes
take up to several days or even weeks.
Using the Kongsberg Mesotech scanning sonar system is a very quick and
simple way of locating objects on a riverbed and due to it’s high
resolution 675kHz and the with MS 1000 software, scanned images can
be seen very clearly especially on the shorter ranges of 40-50 metres.
Also a breakthrough tool for underwater searches for positive identification
is the VideoRay ROV, which is significantly lighter, less expensive,
and more manoeuvrable and compact than other remotely operated vehicles.
With a 250-foot tether, portable power, and a weight of just 8 pounds,
VideoRay helps to expand the range of underwater searches and studies.
The
scanning sonar can be used to locate targets. Then, the VideoRay can
be sent in to inspect the targets and send video footage to the crews
on land or on a boat. Furthermore, the entire search can be recorded
to help investigation teams. Both the scanning sonar and VideoRay can
sustain cold/freezing waters and operate in any type of visibility.
Following positive identification, divers can then be used for the recovery
operation.
The scanning sonar and ROV can also be used for many other types of
operations including reconnaissance operations in the entrances to ports,
marinas and other areas of interest for searching the underside of ships
and boats and water pipes/inlets etc. The systems can be operated from
small boats and also deployed from a bridge or riverbank etc.
Advantages Of Using High-Tech Equipment
Not restricted by environmental conditions i.e. waves, tidal currents,
vision, cold waters and is easily mobilised. The overall riding factors
are that human risk is reduced and operations are quick and efficient
and the data and images are of high quality and can be recorded for
investigation by specialised teams.
Contact
Michael Colley at Gardline Environmental Ltd
Tel +44 (0) 1493 845600
Email: mick.colley@gardline.com
Web: www.gardline.com