Our work in your area

Seagrave Road, Earls Court

What’s happening?

A tunnel access point (or “tunnel shaft”) has been dug at our site in the Earls Court car park, off Seagrave Road.

It is one of the four access points along the north-south tunnel from Wimbledon up to Kensal Green.

Timeline

April 2012

Site preparation: The site is prepared for construction, with the setting up of a temporary site office. Gates and hoardings are erected to secure the site.

April - June 2012

Tunnel shaft sinking: A shaft is constructed by ‘underpinning’. This involves excavating earth and inserting 1m concrete segments down into the ground. This process is then repeated until the shaft depth is reached.

March - Oct 2013

Construction of Earls Court connection tunnel and underground chamber: A tunnel is constructed to connect the base of the shaft with the main tunnel, located to the east of the site underneath Brompton Cemetery.

July 2014

Tunnel boring machine arrives: The tunnel boring machine arrives at the Earls Court chamber under the cemetery, having tunnelled northwards from the Wandsworth site.

Feb - June 2014

Headhouse construction: A permanent building called a headhouse is constructed to accommodate and protect the electrical and mechanical equipment, and allow access to the tunnel for maintenance work.

June 2015

Completion of structural work on site.

All dates subject to change.

Millfields Park, Hackney

What’s happening?

A tunnel access point (or “tunnel shaft”) has been dug at Hackney Substation, in Millfields Park.

It is the easterly access point along the east-west tunnel from Hackney to Willesden.

Timeline

Late 2011 - Spring 2012

Tunnel shaft sinking: A shaft is constructed using ‘diaphragm walls’ made of reinforced concrete. Excavation is carried out under a support fluid which exerts pressure against the trench walls, preventing collapse of the sides.

June 2014

Tunnel boring machine arrival: The tunnel boring machine arrives at the Hackney shaft, having tunnelled eastwards from Eade Road.

June 2014 - December 2014

Headhouse construction: A permanent building called a headhouse is constructed to accommodate and protect the electrical and mechanical equipment, and allow access to the tunnel for maintenance work.

February 2015 - September 2015

Cable installation: Cables are installed from Eade Road to Hackney, creating a subterranean electricity superhighway deep below London’s busy streets.

All dates subject to change.

Eade Road, Haringey

What’s happening?

A tunnel access point (or “tunnel shaft”) has been dug at our site on Eade Road.

It is one of the nine access points along the east-west tunnel from Willesden to Hackney.

Timeline

March - July 2011

Sinking the tunnel shaft: A shaft, approximately 40m deep is constructed by ‘underpinning’: excavating earth and inserting 1m segments down into the ground. This process is then repeated until the shaft depth is reached.

Aug 2011 - Aug 2014

Tunnel excavation: A tunnelling machine (named Cleopatra by local school girl Libby O’Shea) is delivered to site, lowered down the shaft in sections, reassembled, and then starts tunnelling towards St John’s Wood where it is removed, returned to Eade Road, and lowered into the shaft again for tunnelling towards Hackney.

May 2014 - December 2014

Headhouse construction: A permanent building called a headhouse is constructed to accommodate and protect the electrical and mechanical equipment, and allow access to the tunnel for maintenance work.

February 2014 - September 2014

Cable installation: Large drums are delivered and the cables lowered into the shaft through the headhouse, creating a subterranean electricity superhighway deep below London’s busy streets.

Late 2015

Project ends: Cables are joined together, commissioned and the site returned for re-use.

All dates subject to change.

Seven Sisters Road, Highbury

What’s happening?

A tunnel access point (or “tunnel shaft”) has been dug at our site on Seven Sisters Road.

It is one of the nine access points along the east-west tunnel from Willesden to Hackney.

National Grid is also building a new electricity substation at the site to help meet London’s energy needs.

Alongside the new substation, four new retail units are being built along Seven Sisters Road, as well as 44 new residential units, of which 22 will be affordable housing.

The substation has been designed using the latest technology and engineering to reduce its size and meet the highest environmental and sustainability standards. 

We’re re-using the heat produced by the electricity transformers within the residential development and nearby Montem Primary and Samuel Rhodes Schools – although the principle of recycling heat is simple, this complex engineering project will be the first of its kind for National Grid.

Timeline

June 2011

Site preparation: The site is prepared for the works by general clearing and setting up of a temporary site office and facilities. Gates and hoardings are erected to secure the site.

July 2011 – April 2012

Tunnel shaft sinking: A deep shaft is constructed by ‘underpinning’. This involves excavating earth and inserting 1m concrete segments down into the ground. This process is then repeated until the shaft depth is reached.

Spring 2013

Construction of connection tunnel: A tunnel is constructed to connect the base of the shaft with the main tunnel.

April 14 – March 2015

Completion of underground structural works

March - July 2015

Headhouse construction: A permanent building called a headhouse is constructed to accommodate and protect the electrical and mechanical equipment, and allow access to the tunnel for maintenance work.

January - October 2014

Basement digging: the basement for main substation building is dug out.

Summer 2015 - Spring 2016

Electrical equipment fitting: Electrical equipment is fitted in the substation.

Early 2016 - Autumn 2016

Staff welfare building construction: a staff welfare building is constructed.

Early 2017

Residential and retail development: Building of residential and retail development begins.

2019

Completion of works: Residential and retail development is finished and ready for people to move in.

All dates subject to change.

Lough Road, Islington

What’s happening?

A tunnel access point (or “tunnel shaft”) has been dug at the substation site on Lough Road.

The substation at Lough Road is being replaced by UK Power Networks (UKPN), the Distribution Network Operator Covering London, to help meet London’s energy needs.

The site is one of the nine access points along the east-west tunnel from Willesden to Hackney.

Timeline

January – November 2013

Tunnel shaft sinking: A shaft, approximately 40m deep, is constructed by ‘underpinning’. This involves digging earth and inserting 1m segments down into the ground until the shaft depth is reached.

December 2013 – July 2014

Connection tunnel excavation: A small tunnel boring machine is delivered to site and lowered down the shaft to tunnel 700m towards the main tunnel underneath Seven Sisters Road.

April 14 – February 2015

Completion of underground structural works

March 2015 – July 2015

Headhouse construction: A permanent building called a headhouse is constructed to accommodate and protect the electrical and mechanical equipment, and allow access to the tunnel for maintenance work.

March – Late 2015

Substation construction begins: National Grid finishes work on site, handing over to UK Power Networks who start building a new substation at the site.

All dates subject to change.

Canal Way, Kensal Green

What’s happening?

A tunnel access point (or “tunnel shaft”) has been dug at our site off Canal Way, Kensal Green.

It is the north access point along the north-south tunnel from Wimbledon.

National Grid is also building a new electricity substation at the site to help meet London’s energy needs.

Timeline

June 2011

Site preparation: The site is prepared for the works by general clearing and setting up of a temporary site office and facilities. Gates and hoardings are erected to secure the site.

August - Dec 2011

Tunnel shaft sinking: Two shafts are constructed by ‘underpinning’. This involves excavating earth and inserting 1m concrete segments down into the ground. This process is then repeated until the shaft depths are reached.

April - August 2013

Headhouse 1 construction: A permanent building called a headhouse is constructed to accommodate and protect the electrical and mechanical equipment, and allow access to the tunnel for maintenance work.

December 2013 - Mar 2015

Construction of connecting tunnel: A tunnel is constructed to connect the base of the second shaft with the main tunnel to Wimbledon.

April - August 2015

Completion of underground structural works

September 2015 – March 2015

Headhouse 2 construction: A permanent building called a headhouse is constructed to accommodate and protect the electrical and mechanical equipment, and allow access to the tunnel for maintenance work.

Summer 2015 - Spring 2016

Electrical equipment fitting: Electrical equipment is fitted in the substation.

Early 2016 - Autumn 2016

Staff welfare building construction: a staff welfare building is constructed.

Early 2017

Residential and retail development: Building of residential and retail development begins.

2019

Completion of works: Residential and retail development is finished and ready for people to move in.

All dates subject to change.

Lodge Road, St. John’s Wood

What’s happening?

A tunnel access point (or “tunnel shaft”) has been dug at St John’s Wood substation on Lodge Road.

It is one of the nine access points along the east-west tunnel from Willesden to Hackney.

Timeline

September - December 2011

Main tunnel shaft sinking: A shaft, approximately 48m deep, is constructed by ‘underpinning’. This involves excavating earth and inserting 1m concrete segments down into the ground. This process is then repeated until the shaft depth is reached.

January - February 2013

Construction of second shaft and connecting tunnel: A second shaft is sunk and a tunnel constructed to connect the base of the shaft with the main tunnel.

February 2013

Arrival of tunnel boring machine from Willesden: The tunnel boring machine (named Evelyn by local school girl Chastity Nyadu-Bekoe) arrives at St. John’s Wood from Willesden in the West.

May 2013

Arrival of tunnel boring machine from Eade Road: The tunnel boring machine (named Cleopatra by local school girl Libby O’Shea) arrives at St. John’s Wood, having tunnelled South West from the Eade Road site.

September 2013 – August 2014

Headhouse construction: A permanent building called a headhouse is constructed to accommodate and protect the electrical and mechanical equipment, and allow access to the tunnel for maintenance work.

All dates subject to change.

Royal College Street, St. Pancras

What’s happening?

A tunnel access point (or “tunnel shaft”) has been dug at St. Pancras substation on Royal College Street.

It is one of the nine access points along the east-west tunnel from Willesden to Hackney.

Timeline

Late 2011 - April 2012

Sinking the tunnel shaft: A shaft, approximately 38m deep, is constructed by ‘underpinning’. This involves excavating earth and inserting 1m concrete segments down into the ground. This process is then repeated until the shaft depth is reached.

May – August 2013

Spur tunnel construction: A 283m long, 3m wide tunnel is constructed using a tunnel boring machine (named ‘Powering Paula’ by local school children) to connect the base of the shaft with the main tunnel underneath Camden Road.

August 2013

School playground resurfaced: The playground area of Our Lady’s School – which neighbours the site – is vacated and the playground hoarding dismantled and removed. Once the work is finished, the playground is resurfaced and the wall replaced.

September 2015 – May 2016

Headhouse construction: A permanent building called a headhouse is constructed to accommodate and protect the electrical and mechanical equipment, and allow access to the tunnel for maintenance work.

All dates subject to change.

Armoury Way, Wandsworth

What’s happening?

A tunnel access point (or “tunnel shaft”) has been dug at our site at the former gasworks off Armoury Way.

It is one of the four access points along the north-south tunnel which connects our electricity substations at Wimbledon and Kensal Green.

Timeline

Aug 2011

Site preparation: The site is prepared for the works by general clearing and setting up of a temporary site office and facilities. Gates and hoardings are erected to secure the site.

Sept - Dec 2011

Tunnel shaft sinking: A shaft is constructed by ‘wet caisson’, a method used in water bearing ground.

March 2013

Tunnel boring machine arrival: The tunnel boring machine is delivered to site, lowered down the shaft in sections, and reassembled for tunnelling to Wimbledon.

December 2013

Tunnel boring machine returned: The tunnel boring machine arrives at Wimbledon, where it is removed, returned to Wandsworth, lowered into the shaft again and reassembled for tunnelling to Earls Court.

March 2015

Tunnelling complete: Work finishes on the north-south tunnel from Wimbledon to Kensal Green

December 2015 – March 2016

Headhouse construction: A permanent building called a headhouse is constructed to accommodate and protect the electrical and mechanical equipment, and allow access to the tunnel for maintenance work.

Early – Late 2016

Cable installation: Installation of the required cabling for the length of the north-south route from Wimbledon to Kensal Green

All dates subject to change.

Acton Lane, Willesden

What’s happening?

A tunnel access point (or “tunnel shaft”) has been dug at Willesden substation off Acton Lane.

It is the westerly access point along the east-west tunnel to Hackney.

Timeline

April 2011

Site preparation: The site is prepared for the works by general clearing and setting up of a temporary site office and facilities. Gates and hoardings are erected to secure the site.

Jun - Aug 2011

Tunnel shaft sinking: A shaft is constructed by ‘underpinning’. This involves excavating earth and inserting 1m concrete segments down into the ground. This process is then repeated until the shaft depth is reached.

Aug - Oct 2011

Adit construction: A connecting tunnel is constructed to make way for the tunnel boring machine. It is this machine that will be used to tunnel 19 kilometres of the 32km subterranean electricity superhighway deep below London’s busy streets.

Dec 2011

Tunnel boring machine arrival: The tunnel boring machine (named Evelyn by local school girl Chastity Nyadu-Bekoe) arrives on site. It is subsequently lowered into the shaft in order to begin tunnelling in the New Year.

March 2012

Tunnelling begins: The tunnel boring machine begins tunnelling eastwards from Willesden to Channel Gate Road, taking approximately 6 weeks.

Jan 2013 – April 2014

Headhouse construction: A permanent building called a headhouse is constructed to accommodate and protect the electrical and mechanical equipment, and allow access to the tunnel for maintenance work.

All dates subject to change.

Channel Gate Road, Willesden

What’s happening?

A tunnel access point (or “tunnel shaft”) has been dug at our site on Channel Gate Road, Willesden.

It is one of the nine access points along the east-west tunnel from Willesden to Hackney.

Timeline

April 2011

Site preparation: The site is prepared for the works by general clearing and setting up of a temporary site office and facilities. Gates and hoardings are erected to secure the site.

Jun - Aug 2011

Tunnel shaft sinking: A shaft is constructed by ‘underpinning’. This involves excavating earth and inserting 1m concrete segments down into the ground. This process is then repeated until the shaft depth is reached.

May 2012

Tunnel boring machine arrival: The tunnel boring machine (named Evelyn by local school girl Chastity Nyadu-Bekoe) arrives at Channel Gate Road, having tunnelled eastwards from Willesden. Tunnelling operations then transfer to Channel Gate Road, as Evelyn begins tunnelling from there to St John’s Wood.

February 2013

Tunnelling complete: Tunnelling carried out by giant tunnel boring machines eastwards from Channel Gate Road through the shaft at Kensal Green and all the way to St John’s Wood is completed.

January 2014 – February 2015

Cable installation: Cables are installed from Channel Gate Road to serve the section of tunnelling between Willesden and St Johns Wood, creating a subterranean electricity superhighway deep below London’s busy streets.

All dates subject to change.

Riverside Road, Wimbledon

What’s happening?

A tunnel access point (or “tunnel shaft”) has been dug at Wimbledon substation on Riverside Road.

It is the southern-most access point along the north-south tunnel to Kensal Green.

Timeline

July 2011

Site preparation: The site is prepared for the works by general clearing and setting up of a temporary site office and facilities. Gates and hoardings are erected to secure the site.

Aug - Sept 2011

Tunnel shaft sinking at Riverside Road: A shaft is constructed by ‘wet caisson’, a method used in water bearing ground. A segmental lining for the shaft is erected on the surface and then sunk into position.

Dec 2011

Site secured: The site is secured until the arrival of the tunnel boring machine.

February 2013

Tunnelling complete: Tunnelling carried out by giant tunnel boring machines eastwards from Channel Gate Road through the shaft at Kensal Green and all the way to St John’s Wood is completed.

October 2013

Tunnel boring machine arrival: The tunnel boring machine arrives, having tunnelled from Wandsworth. It is then removed and returned to Wandsworth for tunnelling to Earls Court.

July – September 2015

Headhouse construction: A permanent building called a headhouse is constructed to accommodate and protect the electrical and mechanical equipment, and allow access to the tunnel for maintenance work.

All dates subject to change.