Lough Allen Harbour Project
In 2022 Acorn Landscapes were contracted to construct a private harbour on the shore of Lough Allen in Co. Roscommon. This followed a long Planning application involving several Environmental Impact Assessments, Consultation with Waterways Ireland and Inland Fisheries and planning conditions that required constant monitoring of the water quality for the duration of the works. Since 2016 the water levels in the lake have been controlled by the ESB and the Shannon Flood Risk State Agency Working Group. The levels are maintained at much lower levels than pre 2016 and fluctuate by roughly 1.5 metres making it challenging to safely moor boats in the lake.
The proposed harbour had to accommodate a large range in water level similar to that experienced in coastal locations. The Scope of Works included the following:
- Project manage all aspects of the planning and construction of the harbour.
- Installing 150 linear metres of Silt curtain to prevent any disturbance to the surrounding waters and lake bed.
- Dredging a 35-metre-long channel from the harbour entrance to deeper water with all dredged material being drawn off-site to a licenced tip site.
- Daily monitoring and recording of pH and turbidity
- Driving 75 linear metres of Sheet piles to the perimeter of the harbour. These were driven 8 metres deep to retain the breakwaters and allow for the deepening of the inner harbour.
- Driving 2 No. 335mm diameter piles to a depth of 12 metres to anchor the floating jetty
- Construction of 2 No. 30-metre-long stone breakwaters from Rock Armour.
- Installation of an 11-metre-long floating jetty with water, power, lighting and 4 metre access ramp.
- Dredging the harbour area to a depth of 3 metres below mean water level
- Finishing all areas in a way that made it look as natural and unobtrusive as possible.
All works were completed within the In Stream works window between July and September as set out by Inland Fisheries Ireland.