Recording Tyres and Other Junk

Information gathered from fieldwalking on the foreshore, geophysical sonar surveys and reports of polluting junk sent to us on social media are all added to our electronic map called a Geographic Information System or GIS. Information of a similar type is stored together on a Layer in the GIS. Each Layer can be switched on or off to show combinations of information that help us understand what is on the seabed. The GIS includes the whole of the Tamar waterway, comprising Plymouth Sound and its estuaries right up to the furthest tidal reach of the rivers Tamar, Plym, Yealm, Lynher and Tavy.

Click on any picture below to show a larger image.

Some information is included for the whole area such as the depth of water and the material the seabed is made of such as sand, mud, or rock. The water depth is important to know when planning sonar surveys and diving operations. We need to know the material the seabed is made of for many reasons, for example it is more difficult to locate junk on a rocky seabed, so we have to search those areas differently. In areas of sand and mud the junk may be partly or completely buried so we may not detect all the junk using the sonar and a diver clearing up the seabed may find more junk than we expect.

The GIS includes information about historic water depths so we can see how the seabed has changed over time. Historic charts can also help to identify features on the seabed such as old buoy moorings or where dredging work was done.

Shipwrecks

The GIS was started by The SHIPS Project to record information about shipwrecks in the area. The electronic map now includes the shipwrecks frequently visited by sports divers, some that were found by the divers who first explored the bottom of Plymouth Sound, the shipwrecks found by The SHIPS Project and all the ships that are known to have wrecked in the area.

Some of the shipwrecks contain polluting materials and many of the steel wrecks are draped with lost fishing nets, all of which need to be recovered.

The picture (left) shows the location of the well-known shipwrecks visited by sports divers with a few added that are wrecked on the foreshore.

You can find out more about all the shipwrecks around Plymouth on The SHIPS Project website The SHIPS Project

Aircraft Crash Sites

Many aircraft crashed in Plymouth Sound and not all of them were salvaged. The picture (left) shows the locations of the aircraft thought to still be on the seabed, or parts of them still remain. Some of the aircraft have never been found so they may lie on the seabed still to be discovered.

Plymouth Sound and the seas beyond are the last resting place of many aircrews lost in crashes within the Plymouth Marine Park.  All crashed military aircraft or civilian aircraft that were lost during military service in the UK and its territorial waters are automatically designated as ‘protected places’ under the Protection of Military Remains Act 1986.  Diving is permitted on these sites but only on a ‘look but don’t touch’ basis.  Any investigations of air crash sites are done with this in mind, we believe it is important to identify the sites and remember the airmen that were lost. More than 80 Allied and German airmen died in the air crashes in this area with casualty information not available for 9 of the 37 accounts.  Of the 80 known casualties, the bodies of 43 were never recovered from the sea.

When undertaking clean-up operations or removing ghost fishing gear it is important to know where the known crash sites are so the areas can be avoided. It is also important to be able to recognise parts of crashed aircraft so that they can be left alone during clean-ups, and they can be reported to the appropriate authorities. The 1000 Tyres Project team includes professional maritime archaeologists that have training and experience in dealing with crashed aircraft.

You can find out more about all the aircraft crash sites in the area on The SHIPS Project website The SHIPS Project. A 70-page illustrated book by The SHIPS Project about these aircraft, 'Aircraft Crash Sites in and Around Plymouth Sound National Marine Park' can be ordered on the Publications page.

Hulks on the Foreshore

There are approximately 120 timber, iron or steel built boats abandoned in the creeks and rivers around Plymouth. The SHIPS Project team recently located and recorded all of the hulks in the waterway, so their locations are now known, these are important to 1000 Tyres Project as some of the hulks are a source of pollution. Some of the hulks contain oils and lubricants, some are painted with polluting antifouling paint and others contain asbestos. There are many other abandoned boats which are made of GRP or fibreglass with is extremely toxic to the ecosystem and the locations of these are also being recorded.

You can find out more about all the hulks on the waterway on The SHIPS Project website The SHIPS Project. A 247-page illustrated book by The SHIPS Project about these hulks, 'Historic Ships on the Foreshore in and Around Plymouth Sound National Marine Park' can be ordered on the Publications page.

The map on the left shows the locations of the hulks in Hooe Lake and the Cattewater as recorded in the GIS electronic map.

Disused Cables

There are hundreds of abandoned cables on the seabed in Plymouth Sound. Some of the cables were laid to provide electrical power to outlying places like Drake's Island, the Plymouth Breakwater, and the navigation buoys while some of the cables were used for communication before the invention of radio. The seabed in Jennycliff Bay is littered with hundreds of cables that appear to be worn out fishing gear and some can be found on the seabed that have no known purpose. The cables are an entrapment hazard to ships anchors and the older cables made of rubber break down and scatter particles into the water.

The 1000 Tyres team have been recording the location of the cables as they are found by divers or during geophysical surveys, so the GIS includes the locations of the ones we know so far, shown in the picture as brown lines.

Rubbish on the Seabed off Mount Batten

The seabed around the Mount Batten pier and Mallard Shoal is covered with junk of all types. The picture (left) is taken from the GIS and shows the location of the debris, with tyres shown in blue, abandoned cables as brown lines and other man-made objects are shown as squares. The map also includes the land and foreshore at Mount Batten, Mallard Shoal and its flock of navigation buoys and the bathymetry contours.

This area appears to have been a favourite place for dumping junk of all types and this now forms a mess of wire, steel and tyres on the seabed which will be difficult to remove.

Seagrass at Ramscliff Point

The picture (left) shows an area of seabed off Ramscliff Point at the south end of Jennycliff Bay in Plymouth Sound. There is a small seagrass bed in this location which is shown on the map as an area of green hatching. Alongside and within the seagrass are many tyres (blue), abandoned cables (brown) and unidentified junk (squares), some of which is buried and can only be detected by geophysical survey instruments.

The area enclosed by the solid green line is the seabed that we have high resolution side-scan sonar data for. The area to the left has fewer items of debris but this is only because we do not yet have sonar data that covers it, once surveyed properly then we expect to find a similar amount of junk.

The seabed here contains a huge quantity of debris of unknown type and material and much of it could be a significant source of pollution. It is possible that the debris is adversely affecting the ecosystem, so we are working hard to remove it.

Data to identify tyres and other junk on the seabed has been kindly provided to The 1000 Tyres Project by Wavefront Systems Ltd. Wavefront Systems and Sonardyne International Ltd. Sonardyne.

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