Recently hatched just over the road from me is an imaginative way to put a derelict watercourse into sensible eco-use.
An old Victorian lido, for decades unmanaged and unloved, has been transformed into a 'fish-pass' thanks to a partnership between The Friends of Millhouses Park and The Environment Agency. A fish-pass is a man-made conduit which allows fish to travel upstream to their natural spawning grounds where significant barriers - mostly man-made weirs - have prevented them from doing so in the past. In theory a fish-pass creates vital opportunities for fish to move above these obstacles and a major measure of their success is an increase in the river's fish population and, as a result, increased numbers of predator populations (birds and mammals) which depend on them for food. This contributes greatly to good bio-diversity.
The pass at Millhouses is designed to allow the main native fish species, Brown Trout, to bypass the significant barrier - a long weir with a medium gradient - as well as creating new habitat for our endangered, native, white-clawed crayfish which is under threat from its American cousin.
Slightly spooky to think your dog is at risk of a nip from one of these beautiful creatures
but more worrying to think they might, without real concrete action, be wiped out by their American counterparts!
The EA have a short promo video for the fish pass on their website here. The BBC commented on it here. I know of two 'tagged' fish below the weir in September 2011 and it'll be very interesting to find out in March 2012 whether the same fish have managed to navigate the pass.
Here's a very rough video I made this morning of the pass area with my pocket camera (the river is in reasonable but late form)
Millhouses Park Fish Pass 23rd December 2011 from Waterfeature on Vimeo.
Watch the film, 'Kelham Island Hydro', and ask whether what boils down to be a few kettles' worth of hydro-generated electricity is proportionate to the decimation of our little-understood and very fragile river ecosystems.
If you have problems viewing the film from here, please view on Vimeo or watch on Google where you can also download to your pc.