Wallis Road, Hackney Wick
Case study

Wallis Road, Hackney Wick

We were appointed by Hurlington to undertake a Flood Risk Assessment to assess how the development can be implemented safely in terms of Flood Risk and establish appropriate mitigation measures. The commission also included preparing a sustainable surface water and a foul drainage strategy (SuDs)in support of the mixed-use application at a brownfield site at Wallis Road in Hackney Wick.

The site is located in a high-risk Flood Zone 3 area but benefits from protection from flood defences, for up to and including the 1in100year storm events, therefore there was no protection against the additional risks posed by climate change. The site was also located within a critical drainage area.

 

Transport Planning
Infrastructure Design
Environmental Assessment

Details

Challenges posed by the flood risk on Wallis Road

The main challenge posed by this site in terms of flood risk was how to ensure the development would remain safe for its lifetime and not increase the risk of flooding to downstream or surrounding properties. Flood compensation was a particularly difficult challenge that would require some innovative thinking to ensure the development would not displace more flood water than the existing site. This was further complicated by the fact that there were no existing buildings to offset the water displaced by the proposed buildings.

 

 

How we overcame these challenges

Following extensive reviews, discussions and meetings with the Environment Agency (EA) and the London Legacy Development Committee (LLDC) it was agreed that the existing shipping containers that were on-site could be used to offset the floodplain storage from the central cores of the building. The proposed building took up most of the site, so in order to offset any additional loss in flood plain storage and meet the EA’s requirements, the ground floor was allowed to flood. This was difficult as the LLDC would only permit the development if active frontages were provided at the ground floor.

 

 

The team worked to agree that the ground floor would essentially be an outdoor space with a semi-solid wall enclosing a number of container units that would be for flexible work space, retail, café and restaurant uses. This proposal met the EA flood compensation requirements and the LLDC’s active frontage requirements. This was achieved by proposing a permeable louvre/screen at the base of the external wall that would allow water to enter the building. For the individual units internally, this was achieved by implementing permeable roller doors.

Despite previous applications at this site being rejected, the team’s efforts meant that ultimately the development was granted planning permission. As the impacts of climate change are felt more widely, development in flood zones will become more common. This project highlights the importance of engaging with the relevant authorities early in the planning process and being open to flood resistance and resilience measures that will become increasingly key to development in the future.

For more information in relation to this project or assistance with a similar scheme, please contact slecocq@mayerbrown.co.uk or call on 01483 750508


Related content


Request callback

Please leave us your details and we will endeavour to call you back as soon as we can.

Request callback

Contact us for more information

Sign up to keep in touch

Visit our preference centre to sign up for our e-newsletter and update your preferences.

ROSPA
CQMS
Construction Line
Bloom
Mind
Woking Food Bank
bmtrada