The Group Manager Development reported that this application was considered by the Committee at its meeting on 30 April 2015 and Natural Resources Wales (NRW) had submitted a late objection to the development, which indicated that the Flood Consequence Assessment (FCA) submitted which accompanied the planning application, had failed to demonstrate that the consequences of flooding could be acceptably managed in accordance with national guidance over the lifetime of the development.  He stated that NRW’s principle concern was how the proposed development would change the movement of flood waters in a major flood event and the resulting impact of flood waters on third parties.  NRW had also suggested that a larger area of the commercial and residential centre of Bridgend will experience an increase in flood risk depths by up to 100mm.     

The Group Manager Development informed the Committee that Mr John Young of Edenvale Young Associates on behalf of the applicant’s consulting engineers had been invited to make a presentation to address the concerns of NRW.

Mr Young provided the Committee with information on the nature of flooding in Bridgend in order to allow it to make an informed decision about the risks and change in risks associated with flooding.  He informed the Committee how Bridgend currently floods, its frequency, the flood depths and their danger, how the existing risk of flooding is managed and the change in depth of flooding and hazard as a result of the development and how this could be managed. 

Mr Young informed the Committee that Bridgend is protected from flooding by flood defences which run through the Town Centre, hydraulic modelling had been undertaken for the Flood Consequence Assessment indicated the consequences of flood water overtopping the walls upstream of the site flooding over land towards the Rhiw Car Park flooding the triangular area including Market Place, Dunraven Place and Adare Street.  Flooding would continue over property adjacent to Dunraven Place with the entire area including the Rhiw inundated eventually.  He informed the Committee that Edenvale Young had undertaken a hydrological analysis which had been reviewed and approved by NRW.  The hydrological analysis in conjunction with the hydraulic modelling indicate that the flood defences do not overtop in the 1 in 100 year return period event and in the 1 in 1000 return with peak flows in the river increased by 20% to allow for climate change but with no blockage to bridges.  He stated that flood defences are normally constructed to give a standard protection of 1 in 100 years with a 20% allowance for climate change.  The hydraulic modelling has been used to predict the depth of flooding for a 1 in 1000 year event before the construction of the development.  He stated that the existing Rhiw Car Park and the area to the north are located on an area where the danger is classified as dangerous to all (extreme hazard) and “dangerous to Most” (significant hazard).                                         

Mr Young informed the Committee that the NRW provides a flood warning service to Bridgend, with automated warnings provided to all residents registered for the service with floodgates closed in advance of a serious flooding event.  He stated that the development occupies approximately the same footprint as the existing building, but the structure would be slightly less porous than the existing car park.  Water flowing towards the development from the north would be held up in front of the building resulting in a slight increase in water levels to the north of the building.  He highlighted the difference in water levels pre and post construction of the development.  Water levels upstream of the car park and to the south at the A4061 will rise by 0.040m to 0.060m.  He highlighted the change in flood depth at each of the 38 representative properties with very small changes in the classification of hazard throughout the area to the north of the development.  He stated that the changes to flooding as a result of the development can be classified as being minor adverse.  If there were to be a major flood event the risk of the general public and to the emergency services entering this area are so high in both the pre and post development conditions that they would be classified as unacceptable.    

Mr Young informed the Committee the most important consideration is the residents of the development; however, all residential development will be above the 1 in 1000 year water level, with safe access and egress for residents to areas of high ground.  He stated that flood risk to residents can be adequately managed in accordance with Technical Advice Note 15.  The development will cause a slight rise in water levels upstream of the site estimated to be between 0.04m and 0.06m.  However the depth of flooding to the triangular area to the north would be very deep in both the pre and post development situations.  He concluded that the risks to residents can be adequately managed and the minor adverse changes to flood risk to the north of the site are acceptable. 

The Team Leader Coastal and Flood Management informed the Committee that he had considered the hydraulic modelling and hydrological analysis and advised that there would be no more residents put at risk as a result of the development.  He stated that there are sufficient warnings in place with sensors at the flood defences He advised that the development would not present a significant risk and that he considered the risk to be acceptable.  He stated that NRW had accepted the model produced by the consultants and that the development would cause a slight increase in depth due to flooding.

RESOLVED:              That planning permission be granted subject to the conditions set out in the report to the Development Control Committee of 30 April 2015 with the addition of the following condition:-

                                    22.  No development shall take place until the applicant has submitted to and had agreed in writing by the Local Planning Authority a Flood Warning and Evacuation Plan (FEP).  This Plan shall address the matters required pursuant to Appendix 5 of Technical Advice Note 15 Development and Flood Risk and include the following information:

During Demolition/Construction Process:

·     command & control (decision making process and communications to ensure activation of FEP);

·    training and exercising of personnel on site (H& S records as to whom and when);

·   flood warning procedures (in terms of receipt and transmission of information and to whom);

·   site evacuation procedures and routes and provision for identified safe refuges (who goes there and resources to sustain them).

During Occupation of Development:

·   occupant awareness of the likely frequency and duration of flood events;

·   safe access to and from the development;

·   subscription details to Natural Resources Wales flood warning system,

The FEP shall be reviewed at intervals not exceeding 3 years and will form part of the Health & Safety at Work Register maintained by the applicant.

Reason: To limit the effect of flooding by ensuring the provision of a satisfactory means of flood management on the site.