News - Construction News

Mabey Hire and BAM Nuttall to install flood barrier on River Haven

17 May 19

Mabey Hire is teaming up with BAM Nuttall to install a flood barrier on the River Haven to protect homes in Boston, Lincolnshire.

Temporary works specialist Mabey Hire announced the flood barrier which will protect 14,000 homes from tidal floods in Boston. The Boston Barrier project will be led by contractors BAM Nuttall and Mottt MacDonald joint venture (BMM JV) along with the environment agency.

Mabey Hire and BMM JV have already constructed struts and frames to support the excavation area, known as a cofferdam, after 2013 floods damaged around 800 homes. The structural supports are coping with a differing load of 0kN/m up to approximately 500kN/m, coming from the varying currents and tide levels of the water surrounding three of the cofferdam’s four walls.

Project Director at BAM Nuttall Steve Lowder said: “Working with a cofferdam is always tricky, let alone with the added challenge of varying and significant loads due to the tide range and the depth of excavation.”

“Mabey Hire’s rapid strut design enabled us to secure the cofferdam as quickly as possible, so excavation work could progress quickly, safely and efficiently. We look forward to delivering this vital flood prevention scheme, which will protect thousands of homes and businesses from further flood damage.”

Mabey Hire designed the struts with these different load cases in mind, to ensure the cofferdam remains stable and watertight as works progress. The engineering experts supplied a Supershaft Plus hydraulic frame, alongside super Bracing struts made up of 600 box sections and a 350T ram unit.

To stabilise the structure, bespoke box sections were created and welded to the rear of the frame, which sit in the pan of the sheet pile wall to ensure the eccentric loads are distributed around the cofferdam walls. The new £100million flood barrier will be built within the cofferdam to provide further protection to the local area.