Key milestones continue to be achieved at Havant Thicket Reservoir

Major milestones keep being hit at Portsmouth Water’s multi-million-pound Havant Thicket Reservoir project.

Jones Bros Civil Engineering UK and Mackley have combined forces as part of Future Water MJJV Ltd, which is the scheme’s principal contractor.

The on-site team has successfully completed construction of the reservoir’s 232-metre-long culvert and placed 1,000,000m³ of clay across the main embankment and wetlands.

In practical terms, that figure is enough to fill around 800 25m swimming pools, demonstrating the vast scale of material excavated, transported, and compacted.

Clay placement, meanwhile, is a critical part of the reservoir’s construction, providing an impermeable core that will help safely and efficiently retain water.

The culvert has been central to operations, with an average of 50 team members on site for nearly 18 months across close to 200,000 working hours.

The structure, which features a cut-off wall that measures 13 metres wide and nine metres high and took 72 hours to install, includes:

• More than 4,800m³ of concrete, reinforced by 2,400 tonnes of steel bars that, if all laid end to end, would stretch from the Earth to the moon and back nearly four times.
• 2,200 tonnes of Type 1 stone – enough to complete nearly 300 typical garden patios – to build the platforms for the machines and cranes to sit on.

Other notable statistics from the UK’s first major reservoir project in more than 30 years, include:

• The crane used in constructing the culvert travelled close to 150 miles to complete the lifting of the necessary equipment.
• The longest pour took 21 hours from start to finish without interruption, with 450m³ of concrete transferred through two pumps.

Deputy Project Director for Future Water and earthworks construction director Geraint Lloyd said: “Both the completion of the culvert and the clay placement milestone are key moments for the project.

“We are proud of the continued hard work and focus that are key features of every member of the on-site team.

“We can now look forward to hitting more landmark moments as the development progresses.”

Established in the 1950s, Jones Bros owns one of the largest plant fleets in the UK and employs approximately 570 people.

The company is currently working on contracts in various sectors including highways, flood and marine defence, reservoirs, waste management, and renewable energy around the UK.

The company runs an award-winning apprenticeship scheme, which has produced a large percentage of its current workforce, with several of its senior managers having started out as apprentices or in a trainee role. It has recruited hundreds of apprentices over the years.