In December 2010 Head Wier Natural fish pass was opened on the River Mole, UK.  For background, please see the post below ‘Weir today, gone tomorrow’.

The video in this post shows the moment the digger opened the channel and the River Mole began to flow through the Natural Fish pass.  The last part of the video is speeded up a little to show the filling up of the fish pass, so the diggers do appear to be moving a little fast!