On the PROPOSAL of Cllr Fallon

SECONDED by Cllr Cummins

It was AGREED to approve the following Chief Executive recommendations:

Recommendation No 70:

Update the SFRA to include flood zone mapping for smaller settlements.

Recommendation No 71:

Include the following description of historical groundwater flooding in SFRA Table 2:

Historic groundwater flood map: The historic groundwater flood map is a national-scale flood map presenting the maximum historic observed extent of karst groundwater flooding. The map is primarily based on the winter 2015/2016 flood event, which in most areas represented the largest groundwater flood event on record. The map was produced based on the SAR imagery of the 2015/2016 event as well as any available supplementary evidence. The floods were classified by flood type differentiating between floods dominated by groundwater (GW) and floods with significant contribution of groundwater and surface water (GWSW). In addition to the historic groundwater flood map, the flood mapping methodology was also adapted to produce a surface water flood map of the 2015/2016 flood event. This flood map encompasses fluvial and pluvial flooding in non-urban areas and has been developed as a separate product.

Recommendation No 72:

To include the following description of predictive groundwater flooding in SFRA Table 3: Predictive groundwater flood map: The predictive groundwater flood map presents the probabilistic flood extents for locations of recurrent karst groundwater flooding. It consists of a series of stacked polygons at each site representing the flood extent for specific AEP's mapping floods that are expected to occur every 10, 100 and 1000 years (AEP of 0.1, 0.01, and 0.001 respectively). The map is focussed primarily (but not entirely) on flooding at seasonally inundated wetlands known as turloughs. Sites were chosen for inclusion in the predictive map based on existing turlough databases as well as manual interpretation of SAR imagery. The mapping process tied together the observed and SAR-derived hydrograph data, hydrological modelling, stochastic weather generation and extreme value analysis to generate predictive groundwater flood maps for over 400 qualifying sites. It should be noted that not all turloughs are included in the predictive map as some sites could not be successfully monitored with SAR and/or modelled.

Recommendation No 73:

To update recommended measure no. 2 from Section 4.3 of the SFRA Report as follows:

Protect Flood Zone A and Flood Zone B from inappropriate development and direct developments/land uses into the appropriate Flood Zone in accordance with The Planning System and Flood Risk Management Guidelines for Planning Authorities 2009 (or any superseding document) and the guidance contained in Plan Appendix 3.

Site-specific Flood Risk Assessment (FRA) is required for all planning applications in areas at risk of flooding (fluvial, coastal, pluvial or groundwater), even for developments appropriate to the particular Flood Zone. The detail of these site-specific FRAs will depend on the level of risk and scale of development. A detailed site-specific FRA should quantify the risks, the effects of selected mitigation and the management of any residual risks. The assessments shall consider and provide information on the implications of climate change with regard to flood risk in relevant locations. The 2009 OPW Draft Guidance on Assessment of Potential Future Scenarios for Flood Risk Management (or any superseding document) and available information from the CFRAM Studies shall be consulted with to this effect.

Where a development/land use is proposed that is inappropriate within the Flood Zone, then the development proposal will need to be accompanied by a Development Management Justification Test in addition to the site-specific Flood Risk Assessment.

Where only a small proportion of a site is at risk of flooding, the sequential approach shall be applied in site planning, in order to seek to ensure that no encroachment onto or loss of the flood plain occurs and/or that only water compatible development such as Open Space would be permitted for the lands which are identified as being at risk of flooding within that site. In Flood Zone C, where the probability of flooding is low (less than 0.1%, Flood Zone C), site-specific Flood Risk Assessment may be required and the developer should satisfy themselves that the probability of flooding is appropriate to the development being proposed. The County Plan SFRA datasets and the most up to date CFRAM Programme climate scenario mapping should be consulted by prospective applicants for developments in this regard and will be made available to lower-tier Development Management processes in the Council. Applications for development in flood vulnerable zones, including those at risk under the OPW’s Mid-Range Future Scenario, shall provide details of structural and non-structural risk management measures, such as those relating to floor levels, internal layout, floodresistant construction, flood-resilient construction, emergency response planning and access and egress during flood events.

Recommendation No 74:

To update recommended measure no. 5 from Section 4.3 of the SFRA Report as follows (new text in bold):

Work with other bodies and organisations, as appropriate, to help protect critical infrastructure, including flood risk management, water and wastewater infrastructure, within the county, from risk of flooding and to ensure the sustainable development of flood risk management infrastructure and practices.

Actively work with the CFRAM Programmes and catchment-based Flood Planning Groups, including where catchments go beyond the Council’s administrative boundary, in the development and implementation of catchment-based strategies for the management of flood risk - including those relating to storage and conveyance.

Co-operate with the Office of Public Works (OPW) in the delivery of Flood Relief Schemes

Recommendation No 75:

To reference the following Arterial Drainage Schemes under SFRA Table 3 under “Benefitting lands”: Ballyglass (Knockcroghery), Boyle, Corrib-Clare & Moy Arterial Drainage Schemes

Recommendation No 76:

To insert the following text into the SFRA under a new subsection titled ‘Sustainable Urban Drainage Systems’:

Urban developments, both within developments and within the public realm, should seek to minimise and limit the extent of hard surfacing and paving and require the use of sustainable drainage techniques for new development or for extensions to existing developments, in order to reduce the potential impact of existing and predicted flood risk (as provided for Plan policy objective ITC 7.44).  All new large scale developments should be required to provide ‘Sustainable Urban Drainage Systems’ (SUDS) as part of their development proposals (as provided for Plan policy objective GPO5). The integration of nature based solutions, such as amenity areas, ecological corridors and attenuation ponds, into public and private development initiatives, is applicable within the provisions of the Plan and should be encouraged (as provided for Plan policy objective CAEE 8.23). Where multiple individual proposals are being made SUDS should be integrated where appropriate and relevant. 

A Green Infrastructure Strategy for the county shall be prepared and implemented in partnership with key stakeholders and the public (as provided for by Plan policy objective NH 10.24). This Strategy should address the above SUDS issues as relevant. Further to the above, proposals for development should consider Greater Dublin Strategic Drainage Study documents in designing SUDS solutions, including the New Development Policy, the Final Strategy Report, the Code of Practice and Irish SuDS: guidance on applyingthe GDSDS surface water drainage criteria.

Recommendation No 77:

To update the reference to www.cfram.iein the SFRA to www.floodinfo.ie.