Gwynedd Council wants to hear the public’s views on their new plans to build a flood defence at Hirael, Bangor. The public consultation is an opportunity for local residents to have their say on plans that could transform the Hirael Bay coastline.

 

 

The Hirael Flood Alleviation Scheme is a project looking to reduce the risk of flooding to commercial and residential properties in the lower Hirael area over the next 100 years. The project is still in the planning stage and various options are being considered.

The main benefit of the project is the reduction of the risk of tidal and surface water flooding properties in Hirael. The proposed scheme(s) will reduce this risk for 79 properties from a major tidal flooding event up until 2050, after which time, further consideration of the management solutions will be required

Historic flooding in Hirael has been caused by high rainfall coinciding with a high tide. The Afon Adda, which flows underground for 4 km through the centre of Bangor was diverted through culverts which were too small, and therefore when high tide occurred at the same time as peak river flow, the culvert was overwhelmed.

Extensive engineering works to alleviate the flood risk from the Afon Adda were completed in 2008, however, flood risk from the coast remains a risk to the area. With current sea level rise predictions due to climate change, the main risk to Hirael now comes from tidal flooding.

The coastal frontage of Beach Road is comprised of a mixture of defences which are beginning to show their age, and modelling has revealed they would only protect Hirael from a 1 in 3 year flood event (33% chance of such a flood happening in one year).

The current favoured option is building a new sea wall along the promenade, replacing the existing wall which is currently in a poor condition. To provide adequate flood protection, the wall would be raised some 1.3 m (4’3”) above the existing level of the promenade.

The height of the wall will have some impact on the view from the carpark and promenade. Options for mitigating this impact could include raising the land behind.

Flood gates

Access to the seafront is important, and therefore two sets of flood gates will be installed to maintain this accessibility: one on Glandwr Road, and the other next to the Welsh Water pumping station.

These gates will only be closed during periods of high water. Similar flood gates have recently been installed at Y Felinheli (photographed) as part of a new Gwynedd Council-led flood alleviation scheme.

Earth embankment – A short section of flood bank will be built near Welsh Water’s pumping station. This embankment will look very similar to that constructed in Beaumaris. The photo opposite is reflective of the approximate height and appearance of the embankment.

Enhancements

There may be opportunities for improving the overall appearance of the promenade in Hirael through the introduction of new seating areas, plants, flowers and recreational spaces.

This photo is of a flood alleviation scheme recently completed in Littlehampton, West Sussex with similar aspirations.

To have your say on the options please visit: https://hirael.ygc.cymru/public-consultation/?lang=en