The humble cockle shell.
It doesn’t look much other than a bit pretty does it?
Well what if I told you that the cockle shell is the latest weapon in the fight agaist river pollution in Aberystwyth?
No, we haven’t gone mad. It is actually completely true that this tiny shell is being used to clean up the River Rheidol, which has unusually high levels of zinc in its waters.
The source of the zinc is the old mine workings deep in the heart of the Rheidol Valley, which have been leaking zinc into the waters of the River Rheidol for years, along with a number of other metals.
Although the levels of zinc in the water are not deemed to be hazardous to the fish that inhabit the river, the Environment Agency has decided to take action, in a joint project with Newcastle University.
The university has developed a new and innovative filter made from compost, woodchip and cockle shells which it is hoped will encourage a level natural filtration, using natures own chemical and biological processes to clean the water before it enters the river.
In order to treat the water in this way, a new system of pipes has been built to divert the water to a new treatment works, where the filter, which needs no power other than the power of gravity, will hopefully work its magic leading to a cleaner river, with better quality water as a result.
With this in mind, the project is hopeful of meeting the good ecological status criteria set for 2015, which of course includes the levels of various metals in the river water.