Jonathan Hart-Woods, one of our environmental managers tells us about his day out at Sprotbrough Lock open day on the Sheffield & South Yorkshire Navigation.
As some of you may know from reading Judy Jones’ blog, as part of the Sprotbrough Lock stoppage open day on Sunday 16 February, Judy and I led two guided tours looking at the environment and heritage of this unique and interesting area.
The tours started with my explanation of the formation of the Don Gorge. I described how the Don Gorge was the product of glacial activity and how the River Don now follows the route that the glacier carved on its way through the landscape. Along the Don Gorge, the river cuts through a very pure quality magnesium limestone which was very sought after for industrial processing and is still quarried today by LeFarge. Local people will tell you that you’d have to travel to Poland to find a similar limestone outcrop of this quality!
The quality of the magnesium limestone and the availability of water, wood and coal have always attracted industry and settlement along the Gorge from the time of the earliest settlements through the industrial revolution to the present day. From my perspective, the underlying geology gives rise to botanically rich 'mag' limestone grasslands and all the interesting plants this nationally rare habitat supports. Although not in evidence during the timing of the open day, if you know where and when to look you can find yellow rattle, cowslips, and pyramidal and bee orchids to name but a few.
We then went to look at the newly installed fish and eel passes on the Sprotbrough Weir on the River Don. This project was completed in February 2014 and will enable migratory fish such as salmon and sea trout to travel upstream to spawn as part of the 'salmon to Sheffield' initiative by providing a route for the fish to swim around the weir. The new fish pass will also allow coarse fish washed down over the weir to make their way back up stream via the new access route the fish pass provides.
The fish pass installed on the Sprotbrough Weir is a Larinier fish pass (named after the French designer of the pass), meaning that it works by slowing the flow of water through the installation of metal baffles along the floor of the pass. Larger fish are then able to swim up the pass and smaller fish can make their way up the pass by jumping over each baffle and resting behind it before they jump over the next one.
Next to the fish pass is the eel and elver pass, which will help eel and lamprey migrate upstream to breed. This pass has studs along the floor of the pass that slow the flow of the water and allow the eels to climb up around them. The studs are also useful for lamprey to sucker on to and climb up the pass. If you want to give yourself a scare, google lamprey, they’re your worst nightmare made reality; thank goodness they are confined to water and preying on fish . . . for now at least!
The river is now much cleaner than it once was, and so species such as salmon and lamprey are coming back to the River Don, making it all the more important to aid their passage up the river. The river used to be affected by heavy industrial pollution, and Judy talked the group through the reasons for this and the history of the river and surrounding areas.
The tour then looked at the SSSI woodland and some of the invasive plant issues that we have to deal with on an annual basis. We also talked about the difficulty some animals, particularly deer, have getting out of sheet-piled canals and I once again asked for help and assistance from anyone interested in helping me find funding or come up with innovative ideas to prevent this annual occurrence.
Dame Judy then interrupted just as I was in full flow to tell everyone about the Grade 2 listed remains of the Copley pump and what the pump was used for in the early 18th century. The tour ended with a visit to the boundary wall upstream of the pump and an explanation of its connection with World War II.
Judy and I saw over 50 people for the two tours we did and 1800 people visited the open day overall. The sun shone and it was a real pleasure to talk to all the people who turned up, in particular those from Sprotbrough and nearby who had loads of interesting tales and anecdotes to pass on to us. Feedback was really positive and Judy and I can’t wait for the next date on our Waterway Roadshow 2014, hope to see you at the next one.
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