Consultants Recommended Route
West of Coonagh and Tunnel Under Shannon
For Limerick Southern Ring Road - Phase II

Following extensive studies and public consultation, Consultants M. C. 0' Sullivan & Co. Ltd. and COWl of Denmark have recommended to the Elected Members of Limerick County Council, Limerick Corporation and Clare County Council that the Limerick Southern Ring Road - Phase II should run from Rossbrien to the Dock Road, via Ballinacurra and using a tunnel to cross the River Shannon, taking a western route past Coonagh, to join the N18 via an interchange at Cratloe. The project has been included as a pilot Public Private Partnership project to be developed by 2006 in the National Development Plan.

Two route options were presented to the public from a large number of options initially considered by the Consultants. The route could go east or west of Coonagh village. Two options for crossing the River Shannon were also put on public display. A low level opening bridge or a tunnel could cross the river. A high-level bridge option was eliminated earlier, based on technical and cost grounds.

A low level opening bridge with sufficient clearance for general recreational and maintenance river traffic, but with a double leaf opening span to accommodate commercial shipping to and from the Port of Limerick was considered, but the consultants have recommended the tunnel option. A twin box tunnel will be constructed under the River Shannon with portals at either end, to carry the proposed dual carriageway under the River and providing continuous free flow conditions for both road and river traffic.

The tunnel option will deliver substantially free flow conditions for road and river users, while an opening bridge would be subject to interruptions to road traffic to accommodate approximately 400 shipping movements per year to and from the port. The Consultants estimate that between 10% and 20% of these interruptions would coincide with morning or afternoon peak traffic conditions.

"Ultimately, the tunnel option is considered to be preferred to a low level opening bridge because of the improved level of service it will deliver. It will maximise the socio-economic benefits of the scheme to the city and to the region", says Mr. Don 0' Sullivan, Director of Transportation and Water Services, Limerick County Council. "The tunnel option minimises the disruption to road and river users and eliminates the interaction between them. The long-term environmental impact of a tunnel is minor, being hidden from view apart from the terminal portals, though construction impacts will have to be carefully managed to minimise short term damage to the river environment."

A revised low level alignment for the ring road at Ballinacurra is recommended, with a fly-over to carry the existing N20 over the proposed Ring Road "While the high level N20 bridge will have some local visual impact, the overall impact is significantly less than that for the original high level ring road option", Mr. Pat O'Neill, Senior Engineer, confirms.

"The provision of the Southern Ring Road at low level at Ballinacurra can be accommodated by providing a new overbridge to carry the existing N20 over the proposed Ring Road concludes Mr. O'Neill. The flyover bridge for the N20 can accommodate the crossings of the railway and Ballinacurra River, as well as a pedestrian crossing from the Ballykeeffe Estate to the Crescent Shopping Centre.

In making these recommendations, the Consultants have taken full account of the Environmental, Engineering & Economic aspects of the alternatives considered. The recommended scheme takes account of public concerns regarding the N20 crossing at Ballinacurra and full consideration will be given to other concerns identified by the public as the detail of the scheme is evolved

Subject to the endorsement of the Consultant's recommendations by the Local Authorities and the NRA, they will then proceed to the preparation of the Preliminary Design, Environmental Impact Statement (EIS) and other associated documentation required for the statutory processes.

The NRA will also proceed with consideration of the options for tolling the proposed crossing. This is in line with the scheme being a Public Private Partnership project as detailed in the National Development Plan 2000 - 2006.