Monday 23 December 2002

197-02

1970’s monitoring equipment found on Blackness beach

Twelve-year old Callum Miekle from Bo'ness couldn’t believe his eyes when the red plastic ‘frisbee’ he found on the beach at Blackness had a reward tag attached! The piece of plastic is actually a monitoring drogue used by the Lothian Purification Board in the 1970s to measure the tidal flow in the Firth.

The Scottish Environment Protection Agency (SEPA), who replaced the Purification Board in 1996, is absolutely thrilled with his find.

What he found is a Woodhead Seabed Drifter. A number of these were dumped overboard from the Forth Ranger survey vessel at a fixed point in the middle of the Firth of Forth and left to drift. The seabed drifters sink to the bottom of the river and drift with the current on the bed of the river towards the shore. Each drifter is fixed with a reward tag and serial number to encourage anyone who found one to return it to us. Using the time and location each drifter was put in the water, marine biologists were then able to gauge tidal streams, flow and current depending on the time and location they were found.

Oranges were used to gauge surface flow current at that time - a volume of oranges was put overboard and as they float on top of the water we were able to gauge the direction of the current by watching where they came ashore in the Firth!

Richard Park, senior marine biologist for SEPA said: "We are absolutely thrilled at this find and that Calum forwarded it to us. Not only does it show just how rapidly technology has advanced over the 25 years since this was put in the Forth, but also highlights our attitudes to environmental issues. Nowadays, we would never deliberately throw a plastic monitor like this into the Forth knowing that it might not be found or biodegrade for such a long time.”

SEPA’s responsibilities for Scotland's coastline extend up to three nautical miles from the coast. SEPA produces comprehensive information on pollutants to waters that are used to assess any local impacts on coastal waters as well as information that is used internationally to assess the impact on the wider marine environment.



ENDS