Update on Santry River flood protection works

Santry River:  The topographical survey is complete and data from this was put into the hydraulic model analysis which is also completed.

The consultants have produced a report which was forwarded onto the North Central Area Office.  A presentation was made to the area office on 17th September last.

 

The recommended proposal involves restriction of the culverts on the river underneath the Harmonstown Road, to produce a floodplain over local parkland during extreme precipitation events, thus reducing flows in the river downstream in Raheny Village. A leaflet drop to 128 houses on Lein Park, McCauley Avenue, Brookfield and Springdale Road in the area was carried out in the first week in October, asking for a meeting with local residents to answer any queries but no verbal or written responses have been received to date. Detailed structural design is underway for this restriction and should be completed next week.

Further flood walls/embankments will be required to protect against the 100 year event on both sides of the river from the Tyre centre to Main Street in Raheny. Discussions with the landowners of these areas commenced seven weeks ago and they all seem in agreement with the proposal. The height and lengths of these walls are currently being finalised and the detail design of them, assuming the Harmonstown Road restriction, should be carried out this week.

The maximum defence level for the 100 year flood event on the Southside of the Santry River between the Tyre centre and Main Street is around 1m high including 300mm of freeboard (safety margin). The maximum defence level on the North side of the river is 500mm including 300mm of freeboard, which may be constructed as an embankment. Flood defence extent drawings are currently being finalised.