There are small streams in Sheffield which are that colour permanently - running into the the rivers Loxley, Rivelin, Sheaf and Porter from the Greystones/Ringinglow/Stannington hills and plenty into the Don upstream from Hillsborough. Some of them are sough-like, with constructed tails and recently I've found a few of very small-scale ones that would be very difficult to get into, which may just be old culverted land-drains, but they look like 'mini-soughs'.
I don't think they're that much of a problem given their relative outflows, but I think 30 years ago it was probably a different matter. When was a kid growing up in Rotherham, the river and canal were totally forbidden zones. But we had the giant shale heaps from the opencasting to play on, so we were happy...