RIVER BOLLIN/MANCHESTER AIRPORT/LANCASHIRE
Apparently, the Bollin Tunnel can be fished, although, it seems some of the locals prefer to keep it to themselves and don’t like it being published.

Trout of up to 3lbs have been caught.

The river also holds chub, dace, roach, perch and pike.

If it’s trout on a fly you’re chasing, I would fish heavy nymphs to get them down among the cascades within the tunnel but be prepared to snag up frequently.  It’s a cost of doing fishing here.