Shane Ross (Dublin Rathdown, Independent) | Oireachtas source

My understanding is that it is not guaranteed, despite the pre-appraisal.

The expected benefits of the Slane bypass are that it will provide a bypass of Slane village, provide an enhanced living environment within the historic village, reduce journey times and traffic delays in the vicinity of Slane and enhance access between Dublin and the north west region. This scheme is currently at route selection stage. The route selection report is being finalised and is due for publication in 2019. A pre-application consultation process is under way with An Bord Pleanála. It is anticipated that the scheme will be published in late 2020. Subject to receiving planning approval the scheme may then progress to construction. The estimated construction timetable is three years with an anticipated completion date of 2024.

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