COMHAIRLE CONTAE ÁTHA CLIATH THEAS
SOUTH DUBLIN COUNTY COUNCIL
MEETING OF ENVIRONMENT, PUBLIC REALM AND CLIMATE CHANGE SPC
Tuesday, February 02, 2016
HEADED ITEM NO.
River Poddle Flood Alleviation Scheme
Options for dealing with flood risk on the Poddle River were identified under the Eastern Catchment Flood Risk Assessment and Management (ECFRAM) study and consultations with the public took place in 2013. The preferred proposals for flood mitigation measures on the River Poddle include:
- Flood walls and embankments with flood storage in Tymon Park
- Culvert inlet screens
- Flap valves
- Sealed manholes
The proposed works for the overall scheme cross two Council boundaries and South Dublin County Council (SDCC) working in collaboration with Dublin City Council (DCC) will take the proposals forward through planning and eventual construction. Documents for the procurement of the design and environmental consultants for the Scheme are currently being finalised. The consultants will also prepare a detailed Cost Benefit Analysis for the proposed works.
It is intended to divide the scheme into two phases: the first phase is the works at Tymon Park and the second phase is the works downstream of Tymon Park.
Subject to the identification of an environmentally viable and cost beneficial scheme and successful completion of the planning process it is hoped to be in a position to commence construction of the Tymon Park works in 2017 and the downstream works in early 2018.
Construction of the works in Tymon Park will take about one year while construction of the remainder of the works will take about two years.
The Office of Public Works (OPW) has given a commitment, in principle, to funding a viable, cost beneficial and environmentally acceptable scheme for the Poddle and has made indicative provision for its cost in its Multi-Annual Capital Budget Profiles.
The works proposed to alleviate flooding on the Poddle are to be designed to the standard level of protection often referred to as the 100-year flood, which is to prevent flooding during events with a 1% annual exceedance probability (AEP) for fluvial floods. The design will take account also of climate change.
Interim works carried out to date by SDCC involve new debris screens placed on culverts on the river which are monitored remotely by telemetry. Any alarms can be responded to quickly so that debris build up can be removed in good time.