I returned to Catrine first thing this morning to see the shutters come off yesterday’s concrete pours. Everything seems fine and the joiners quickly set about fitting the formwork for the crest of the weir that they hope to pour tomorrow.
Over the weekend, water will flow through the bypass pipe allowing the concrete to harden and strengthen. before being restored on Monday. The top end of the bypass pipe will be sealed with a 1 tonne plus, concrete plug that will be removable if work is ever required in future.
Finally I’ve added a photo of the new boulder field that has been installed at the upper weir. This serves three purposes. Firstly it helps stabilise the upper weir structure. Secondly it should deter most fish from attempting to swim over the smooth surface of the dam and finally it will also help guide fish to the fish pass. It is constructed of rock armour concreted together to form a large stable mass. I notice the smaller boulder near the right bank haven’t been concerted and unless they are, they will disappear rapidly with every spate. I will check if this is included in the plans.
Progress has been made and once the weir crest is complete and the plug is in the pipe, I can’t wait to see how it all looks and performs during the next spate. Almost all the work so far has been to improve fish migration and everything looks as thought it should work well with just one exception… the eel pass. I just can’t believe this will work at its current levels. The intake is between 750mm and 1000mm above the water level and unless there is a pump planned to lift water to the pass (and there isn’t), I fully expect this will have to be redone. I did express concerns at the time it was installed (for which I was called an idiot!) so I’ll just wait and see. This idiot knows water doesn’t flow uphill.