The Environment Agency’s £100 million Boston Barrier scheme has reached another milestone with the arrival on site of the second set of defence gates on Friday 4 June.

Image: testing the primary barrier gate in August 2020

The vertical sector gates at the Port of Boston were transported across the North Sea from Rotterdam by barge, as was the primary barrier gate, which opened in December 2020.

The Boston Barrier scheme is expected to be fully completed at the end of 2022. Work on the scheme, which was identified by the government as critical infrastructure, has continued in line with the government’s coronavirus advice.

Adam Robinson, Boston Barrier project director for the Environment Agency, said:

“The delivery of the vertical sector gates is another exciting milestone in this important scheme which takes us one step closer to final project completion.

“These new gates will replace the current ones installed at the Port of Boston wet dock entrance, which were overtopped in the 2013 tidal surge. They will ensure continuity in the defence and better protection of homes and businesses downstream of the primary barrier gate over the next 100 years.”

The gates will be lifted from the barge by crane onto Self-Propelled Modular Transporters, a type of remotely controlled vehicle, and will be driven to a temporary storage location on site in the coming days.

They will then be installed in the wet dock entrance by scheme contractors BAM Nuttall & Mott MacDonald Joint Venture (BMMJV) later this year.

Once installed and fully operational, the gates will better protect a further 524 properties from tidal flooding. This will take the total number of homes and businesses in Boston being better protected by the scheme to more than 14,000.

Hollandia Infra, the Dutch company which manufactured the gates, have painted the gates with 3 layers of a 150 micrometre technical coating, thereby ensuring they have sufficient corrosion protection for their 100-year design lifetime.

Once in place the wet dock entrance gates will be one of the final large components of the Boston Barrier scheme.

The scheme, along with the adjoining Boston Haven Banks improvement scheme – a separate Environment Agency project, which is raising the river banks either side of the Haven – is part of the Boston Combined Strategy, which provides a 100-year flood risk management plan for Boston.

The Boston Barrier scheme was given the green light by the Secretary of State for Environment, Food and Rural Affairs in 2017. Work began on site in January 2018.

The primary Boston Barrier gate is now fully operational and can be raised in just 20 minutes.

With the whole of the £100m Environment Agency scheme now two-thirds complete, the project will provide Boston with one of the best standards of flood defence outside of London. Once the scheme is fully completed in 2022, flood risk to over 14,000 homes and 800 businesses will be greatly reduced and allow for the effects of climate change for the next 100 years.

The Boston Barrier is a critical infrastructure project and national priority project for the Environment Agency, delivered by BAM Nuttall Mott MacDonald Joint Venture.

Over 800 properties were flooded across the town in a tidal surge on 5 December 2013. The surge highlighted the need for improved tidal flood defences in Boston, and the barrier scheme became a National Priority Project for the Environment Agency’s Six-Year Programme six months later.