The River Blackwater is a tributary of the Shannon which once supported two mills – Blackwater Mills and Rosmadda Mills. The construction of the Shannon hydroelectric scheme in the 1920s involved making a large culvert to allow the head race canal feeding the power station at Ardnacrusha to cross the Blackwater. At the time of the culvert’s construction in 1926 both of the nearby mills had fallen into disuse although the mill race for Blackwater Mills can still be seen at the cache site.
This cache is part of a series of caches looking at the history and impact of the Shannon hydroscheme:
Parteen Weir
Blackwater Culvert
The recommended parking is on the headrace canal bridge from which you can see the power station building itself. If you need to cross the bridge, please use the pedestrian path as the road across the bridge is narrow and the traffic moves fast. Take great care when opening your car door. Cars are often parked here as people like to walk out the canal banks for exercise. The infall of the culvert is on the left bank of the head race canal when the power station building is at your back (i.e. looking upstream). You will be heading upstream away from the power station building on route to the cache. There are stiles in place to allow people to cross onto the canal bank from the road. To reach the cache you must walk down the steep grass banking. Sturdy/waterproof footwear is highly recommended. When you reach the culvert you will see a ramp that the water flows down before entering the long concrete tunnel. There is also a narrow wooden slot fish pass on the far side of the ramp. Above the concrete arch you will see the date of construction (1926) in relief. Looking upstream of the culvert you will see that the River Blackwater curves to the left but there is also a straight silted channel which was the Blackwater millrace.
BYOP
Congratulations to Wassy42 on the FTF!