Kelston Sparkes completes initial groundworks at Hinkley Point Connection
Leading earthmoving contractor, Kelston Sparkes, was awarded the groundworks contract for the overhead section of the Hinkley Point Connection project in 2020. This was for the southern section of the innovative National Grid Project to create a new high-voltage electricity connection between Bridgwater and Seabank, near Avonmouth.
The connection, some 57kms long, comprises 48.5km of overhead lines and uses the world’s first operational T-pylons. The remaining 8.5km of cable runs underground through the Mendip Hills Area of Outstanding Natural Beauty leaving it free of pylons for the first time since the 1960’s. Upon completion it will provide new sources of low-carbon energy for homes and businesses in the South West.
Working for Tier 1 contractor, Balfour Beatty, the work on the southern section stretched from South of Bridgewater to Biddisham and entailed the installation of circa 12km of temporary haul roads and the construction of 45 work areas (a combined piling mat and crane platform area) across the Somerset levels ready for the erection of the pylons. The unique nature of the low-lying levels meant that the work included building a network of ditches, damning off and reaming multiple water courses and constructing culverts to divert water under the haul roads. Each watercourse required a bespoke solution and required careful planning to ensure all measures were reversible at the end of the project.
Of course, sustainability is at the heart of every construction project and Kelston Sparkes was delighted to partner with a novel company called Soil Science to minimise the aggregate requirement for the haul roads and work areas. The original design required the stripping of the topsoil and laying geogrid and 6F5 aggregate. Soil Science developed the SUREGROUND™ reversible soil enhancement system which mixes in-situ site soils with a proprietary binder to stabilise the soil and increase the load bearing capacity of the ground. By embracing this technology, it was possible to reduce the size of soil storage areas and eliminate the requirement for large quantities of primary aggregates; reducing lorry movements and reducing vehicle related emissions. This helped to reduce installation time and ensured community relations were preserved thanks to fewer vehicle movements on the local roads and associated noise, dust and vibration levels. Ultimately, 50% of the whole scheme was completed with the SUREGROUND™ temporary stabilisation solution which is fully reversible.
The installation of the Southern section has now been completed, and the team from Kelston Sparkes is currently on site commencing the removal of the haul roads and the complete reinstatement of all Somerset levels.
David Swann, Contracts Director of Kelston Sparkes, has confirmed the company has since tendered to complete the works on the Northern section of the project and thanks to the experience gained and the successful delivery of the initial section, that work started in 2021;
“We were delighted to win the tender to deliver the overhead section of this prestigious project and to continue strengthening our partnership with Balfour Beatty. This project played to our strengths, enabling us to produce the required aggregates within the quarries where we currently operate, undertaking all the transport and placing of temporary roads and work areas and then finally removing and repurposing the aggregate on other projects, thus significantly reducing the overall carbon impact. In combination to this, it’s been fantastic to work with Soil Science, who enabled us to deliver a really sustainable solution with their innovative soil enhancement system.”