Belfast Tidal Flood Alleviation Scheme completed
Completed in December 2024 at a cost of £33 million, the Belfast Tidal Flood Alleviation Scheme aims to protect over 3,000 homes and businesses from tidal flooding.
Infrastructure Minister Liz Kimmins MLA visited the Belfast Tidal Flood Alleviation Scheme on 26 March 2025, and said: “Adapting to climate is one of my Department’s seven foundations for a better future. While we cannot prevent all flooding from happening, we can reduce the impacts with appropriate infrastructure investment.”
Construction on the project began in July 2022 and it was initially expected to cost £17 million, however this figure almost doubled due to inflation and changes to the position of flood defences on third party land.
Spanning 8.5km, the network comprises both permanent and temporary flood defences from Stranmillis Weir to Belfast Harbour. It is due to integrate with Lagan Pedestrian and Cycle Bridge, the preliminary works of which commenced in 2024.
According to the Department, the scheme was designed to provide “a high level of protection” up to the mid-2080s, and future adaptations could extend this by an additional 40 years. Rising sea levels caused by climate change pose increase flooding risks to Belfast, with much of the city between one and two metres below extreme tide levels.
Kimmins says: “We are already experiencing a change in our weather with increasingly severe storms and the design of these flood defences takes into account climate change projections to 2080.”
The Department for Infrastructure estimates that over the 100-year life of the scheme, the level of flood risk is estimated to cause direct flood damages of £168 million valued today. Impacts on the local economy are estimated at an additional £87 million as per economic national appraisal guidance, but the Department indicates that the scheme can protect against these risks.
The Minister concludes: “I would also like to commend the team who have designed the defences to integrate with their surroundings. This vital work contributes to protecting a thriving city where people want to live and work, to visit and invest – both now and in the future.”
