Less fuss and bother

More than 1,700 customers will benefit from a £126,000 project to replace and rebuild high voltage (HV) overhead lines in rural Northamptonshire.

The first phase of the work from Thenford to Middleton Cheney has already been completed and seen the replacement of 2.2km of ageing poles and conductors. These had been in place for more than 40 years.

Phase one, which took eight weeks to complete, also included the replacement of overhead line (OHL) on a 0.7km spur serving Farthinghoe Recycling Centre, near Brackley.

Much of the affected OHL crosses fields and roads in rural Northamptonshire – a factor which has called for detailed negotiations with landowners to find a schedule that suits everyone.

Graeme Hill, an 11kV Planner based at Northampton, said: “Our technicians and wayleave specialists have been working closely with landowners to negotiate the access and egress we need to replace our assets, and to make sure landowners are happy with the timetable for coming onto their land.

“If they are growing crops or have livestock on the land or there has been a lot of wet weather they are understandably less keen, particularly as we use very large vehicles.”

Close working relationships with landowners have also enabled engineers to agree temporary storage areas for new poles and materials along the route of the OHL. These landowner-approved storage facilities will be used by WPD for the duration of the project.

Thenford investment 1: Customers in rural Northamptonshire will benefit from the lofty project.

Disruption, what disruption?

One of WPD’s top priorities throughout the project is to minimise the effect on customers.

Engineers have installed pole-mounted switches called ABSDs (Air Break Switch Disconnectors, sometimes known as ABIs) to avoid customer disruptions. ABSDs are used to split the planned rebuild into smaller, manageable sections and to reduce the impact of future shutdowns, including the likelihood of customer interruptions.

In fact, customer supplies will be unaffected throughout the work. For the first phase, generators were used to keep customer supplies on. These will be employed again during the second phase.

We have invested heavily in ‘sync on’ generators, which make it possible to transfer customers’ supplies to generators without any interruption. This is carried out before engineers switch off the HV overhead line.

Four generators of varied power were used throughout the eight-week period to deliver uninterrupted supplies to more than 70 customers. These replaced the transformers which are typically used to supply customers as they required refuelling daily.

Close liaison with other agencies also minimised disturbance for local people by successfully averting traffic disruption.

Although the OHL project involved crossing the busy A422, this was done while the road was closed as part of an existing bridge repair programme.

As an added boon to customers, the introduction of new poles and conductors will increase the network’s reliability and resilience, making it less prone to faults.

Thenford investment 2: Technician Jon Lay inspects a section of the revamped network.

In our Nature

Phase two will concentrate on 1.3km of OHL from Thenford Primary substation to Middleton Cheney and will include moving 400m of HV line out of a local beauty spot.

Special attention has been given to the work at Farthinghoe Nature Reserve to avoid disturbing the wildlife. Environmental surveys have identified nesting birds and badgers’ setts and have resulted in subtle alterations to the programme to rule out any adverse effects on this beautiful reserve.

The repositioning of the line will also remove issues with overhanging branches which have previously called for regular tree trimming.

The final stage of the project is due to be completed in October