RAF WaddingtonHigh Voltage Upgrade
High Voltage Upgrade
Client: Defence Infrastructure Organisation (DIO)
Location: RAF Waddington, Lincoln, LN5 9NB
Type: Fixed price contract
Services: HV Upgrade
Main Contractor: Morgan Sindall
Architect: Mott MacDonald
Duration: 40 weeks
RAF Waddington first opened its doors as a Royal Flying Corps training base in 1916. A century on, it is one of the most important military bases in Britain: the UK hub of intelligence, surveillance, target acquisition and reconnaissance, collectively known as ISTAR. It is also one of the Royal Air Force’s busiest operational airfields, accommodating six badged RAF squadrons and nearly 3000 people.
Inevitably, ongoing modernisation and recent infrastructure upgrades had placed an increasing burden on the camp’s energy demands. To meet the present and future needs of the site, the DIO decided to commission a partial HV upgrade of its power supply, more than doubling the existing 3.5mVA capacity to a new 7.5mVA of electrical supply from Western Power Distribution.
Working with main contractor Morgan Sindall, WT Parker helped to facilitate a new capacity duplicate incoming supply for the base, supported by 3mVA of embedded diesel generation, and including a partial renewal of the HV ring main cables. For us, the project was an opportunity to provide world class HV engineering for one of the UK’s most strategic and prestigious military institutions.
- Doubling of the camp’s electricity supply from 3.5mVA to 7.5mVA.
- 2.5 miles of trenches excavated to a depth of 1.2 metres.
- Workforce of 12 engineers employed across the project.
New sub-station and standby set house
RAF Waddington’s power supply follows the typical model for an airfield site: an Intake Sub-Station (ISS) is linked remotely to a Standby Set House, separated by several hundred metres to provide security of supply in the event of enemy action. For the present upgrade, Morgan Sindall demolished and replaced both structures prior to installation. Our role was to provide the electrical fit-out for the new buildings, with two adjacent 1.5 mVA transformers, and two 1.650 MW generators, in the Standby Set House.
One of the major challenges of the work involved the laying of cables to the stations. In total we dug out 2.5 miles of trenching for the project, to a depth of 1.2m. Waddington’s relative age added to the complexity of this operation. Generations of military personnel have used the site over the past century, leaving a considerable legacy of utility services, BT secure lines and other obstacles below ground level. While the Statement of Known Hazards identified most of the potential obstructions, our engineers detected and dealt with several others during the work itself, including an unmapped bunker dating from World War II and a pile of asbestos sheeting. Both involved rapid but essential rerouting of the trenching and the work continued with minimal delay.
Our work on the upgrade had to take account of several changes during the fit-out. One of these involved the location of the Standby Set House itself. When a BT secure line was identified running through the proposed footprint of the new building, the construction plan was altered to move it several metres away and at a 90 degree angle. We worked quickly to absorb the changes, recalculating the cabling requirements and the necessary re-piping to the generators. Separately, alterations also had to made to the Schneider switchgear version that we had proposed for the ISS and Set House. Post-tender, the company announced that it would no longer be supporting its Visax switchgear beyond 10 years. After a swift cost comparison and re-quotation process, our designers advised upgrading to Schneider’s newer Genie Evo range, and this was accepted by the client.
Softening the impact
RAF Waddington is a busy site with sensitive operational needs. As such, we needed to provide the base with a programme of works that caused the least amount of disturbance possible. This was achieved partly through a bespoke traffic plan, with flow plates and carefully scheduled excavations to minimise disruption to the camp’s road network during cable installation. For the upgrade itself we designed a phased shutdown programme of the existing HV system, bringing the new ISS and SBSH HV systems online as the old ones were decommissioned. We were also able to reduce costs by avoiding the use of temporary generators during the switchover. In all cases we worked closely with the Appointed Persons to make the process as open and efficient for the camp as possible, with 45-day notification of outages, and overtime restricted to weekdays in order to cause less disturbance at weekends.