Depart from the car park at the foot of the viaduct, near the water treatment plant.
(S/E) With your back to the car park, head towards the river.
(1) When you reach the riverbank, turn right onto the marked path along the river and continue along the marked path until you reach the junction with a road.
(2) Follow it to the left and cross the bridge.
(3) Turn left to rejoin the path and continue along it until you reach the viaduct.
(4) Before the viaduct, take the bridge on the left, turn left and walk along the water treatment plant to return to the car park (S/E).