Hampstead Heath Flood Prevention Pond Project

Key Facts

  • Client: City of London
  • Value: £15 million
  • Location: Hampstead Heath, London

Hampstead Heath is one of London's best loved green spaces and has 30 beautiful ponds.

Hampstead Heath is one of London's best loved green spaces and has 30 beautiful ponds. Although they look natural, most are formed by man-made earth dams and are up to 300 years old. Detailed studies show that the existing earth dams on the Highgate Chain and the Hampstead Chain of ponds could fail in a large storm, putting lives, residential properties and infrastructure at risk. Works are therefore required to safeguard against flooding, comply with reservoir legislation and protect the future of the heath’s famous ponds.

The solution for London

One of the main objectives of the scheme was to create a passive system that does not rely on any mechanical system or human intervention. To meet this objective, a total of 112m of concrete culverts are being installed to carry the overflow from each pond down to the next one in the chain. These are being precast off site which cuts down deliveries to the heath by 70% and eliminates the risks associated with pouring concrete in a sensitive aquatic environment.

Our project staff has been fully integrated with the Corporation’s Heath team since March 2014 under an ECI contract, inputting into the design of the proposed scheme and working together to limit the impact the works will have on peoples’ enjoyment of the Heath.

Working collaboratively with project stakeholders

The Ponds Project Stakeholder Group was set up during the ECI stage and together we review proposed designs and their long term impact on the landscape, including management, logistics, communications and implementation of the Ponds Project.

A Community Working Group was also set up as part of the planning conditions by Camden Council, made up of local councillors, societies with an interest in the Heath, residents associations and Heath users. The group meet monthly to discuss progress and resolve any concerns. BAM Nuttall team members attend these meetings to discuss the construction activities which may affect users, local residents and proposed wildlife and mitigation measures. The close working relationship we have developed has been of great benefit to the project delivery.

“We have been working closely with the BAM Nuttall team to make sure we bring this essential work to a conclusion with the minimum of disruption. Bringing them in on an ECI basis has meant the project team has been able to integrate with our Heath Conservation Team, Now everyone knows and understands who is working on what and are able to work well alongside one another.” Tom Creed, Engineer at the City of London

Environmentally sensitive

We are supporting the City of London to achieve an ‘Excellent’ CEEQUAL award.

Early on in the consultation process, some ponds were identified as sensitive because of their landscape or ecology and this includes Vale of Health. As a result, the scale of work at this pond was minimised as far as possible. As part of the designs, a new spillway is needed to allow water to leave the pond safely, in the event of a large storm, without causing any damage to the earth dam. The spillway will be grass-lined and sowed with a wild flower mix, which has been specifically designed to fit in with the Heath’s landscape. The designs have also been carefully considered to save the iconic Giant Redwood. BAM’s careful planning means the pond will remain open for anglers throughout the work and when complete, dogs will still be able to enter the water from the southern corner.

Once the project is fully completed, the Heath will be a safer place for downstream residents and the ponds will benefit from greater ecological diversity, better water, views and paths, new reed beds and other important wildlife habitats.