Wilsele - Pellenberg

Janaury 2018

General information session before work starts

On Monday 17 December, Elia organised an information session at Ontmoetingscentrum Genadedal on the work scheduled as part of the Wilsele-Pellenberg cable project. Informative roll-ups taught around 60 visitors more about the project's purpose, schedule and impact (on mobility), while the Elia project team and contractor involved were on hand to provide further information and answer questions. Go to the Documents tab to view and download the roll-ups and a flyer about the project.

Elia will begin work in January, starting on the first cable sections in Kessel-Lo and gradually moving towards Pellenberg. We will post a letter in advance of the work to those local residents specifically expected to be affected by the project, notifying them of potential disruptions.

December 2018

Elia organises information session on the Wilsele-Pellenberg project

Elia is organising an information session for local residents on the laying of the underground cable route between the high-voltage substation in Wilsele and a transition substation being built on the border between Kessel-Lo and Pellenberg. Residents can visit the information session at any time between 5.30 p.m. and 8 p.m. on the following date and at the following location:

  • 17 December 2018
    Ontmoetingscentrum Genadedal
    Velderblok 2A
    B-3010 Leuven

During this information session, Elia will talk about the project's purpose, schedule, works and impact (on mobility). Our project managers will be on hand to answer any questions.

September 2018

Construction of new transition substation in Pellenberg to begin in October

As part of this project, in October 2018 Elia will begin building a new transition substation at Wimmershofpad on Lange Lostraat in Pellenberg.

Elia will first prune and remove trees and bushes to make space for the new transition substation, after which Elia will lay foundation slabs and metal supports to which the electrical equipment can be attached. Lastly, Elia will install the electrical equipment, including a transformer, cable joints and overvoltage conductors. Elia is scheduled to complete all work by late 2019.

The disruption to the surrounding area caused by the work on the transition substation will be limited to the coming and going of trucks carrying materials.

Current situation


Future situation


July 2018

Elia completes the permit process

Elia obtained the environmental permit for the Wilsele-Pellenberg project in July 2018. The permit was issued by the Flemish Government's Environment Department. Elia will spend the summer preparing for the start of the work and will begin laying this new 70-kV high-voltage cable in autumn 2018.

The project 

Elia is laying a new 70-kV underground cable connection between the existing high-voltage substation in Wilsele (Aarschotsesteenweg) and a new (to be built) transition substation in Pellenberg (Wimmershofpad). This transition substation is needed to link the new underground connection with an existing high-voltage overhead connection.

Route through Wilsele and Kessel-Lo

The new 70-kV cable connection stretches seven kilometres through Wilsele and Kessel-Lo. The route was chosen in consultation with the local authorities, incorporating a range of considerations in order to minimise its impact. Busy thoroughfares and private land will be bypassed or drilled under where possible.

The route of the 70-kV underground cable connection begins at the existing Elia high-voltage substation in Wilsele (Aarschotsesteenweg). From there the cable runs along the Leuven-Mechelen railway line, the Eénmeilaan roundabout, Domeinstraat, Genadeweg, Schoolbergenstraat, Kortrijksestraat, Meugenslaan, Wimmershofpad and Kamperfoelieweg, up to the new transition substation in Pellenberg.


The benefit of the project

The security of supply of the Pellenberg campus and Leuven area

Laying the new 70-kV connection is key to guaranteeing the security of supply of the UZ Leuven Pellenberg campus and the greater Leuven area.

The dismantling of the Kessel-Lo - Tienen high-voltage line

Once the new 70-kV underground cable connection is up and running, Elia can eventually dismantle the 70-kV overhead line between Kessel-Lo and Tienen. This high-voltage line must be decommissioned as it has come to the end of its service life.



In September 2018, work began in Wilsele between the E314 motorway and the Leuven-Aarschot railway line near the Ecowerf and Aquafin sites. Directional drilling is taking place under the railway line, after which the cable will continue to be laid in the direction of Kessel-Lo. Work on the streets of Wilsele and Kessel-Lo is currently scheduled to start in early 2019 and end in late 2019.

In October 2018, we will also start work on the new transition substation in Pellenberg. We will first prune and remove trees and bushes to free up space before starting on the electrical work. We are scheduled to complete all work by late 2019.


Laying a 70-kV underground cable

The new underground connection comprises three cables in total, all of which are laid in the same trench. This process encompasses the following six phases:

1. Consultation with municipalities and towns

Elia consults the municipalities/towns involved and makes arrangements with local authorities and services.

2. Studies

The field survey analyses the location of existing utility lines, potential obstacles along the route, and other archaeological factors. This detailed study determines the exact location of the underground cables. A topographical survey is performed. Elia arranges the signage needed and potential diversion routes.

3. Digging of trenches

Elia begins digging the trenches in which the cables will subsequently be laid. The trenches are approximately 2 metres wide and 1.3 metres deep. It takes two months to complete each cable section (around one kilometre).

4. Directional drilling

Elia carries out directional drilling at intersections, waterways and railways. Directional drilling is a trenchless technique where drilling takes place between six and ten metres underground. Once drilling is complete, the cables are pulled underground through conduits.

5. Cable pulling through the trenches

A cable reel is used to lay the cables in the trench over a distance of around one kilometre. The cables are laid in a special type of sand in order to control the temperature and are covered with protective plates.

6. Restoration of the site

Elia restores the site to its original state once work is complete.

Features of laying the 70-kV underground cable

Elia uses two types of trench to lay the 70-kV cable connection along most of the route:

Type A trench

Type A trenches are the standard and most commonly used type of trench. Cables are laid in an open trench in a bundle.

Type B sleuf

Type B trenches have the same structure as type A trenches. Elia uses type B trenches at road crossings with little traffic. They are temporary open trenches in which conduits are laid. We then pull cables through these conduits.

Directional drilling
Elia performs directional drilling when working on waterways, busy intersections or crossings where type B trenches are not an option. Directional drilling is a trenchless drilling technique employed by Elia when laying cable connections under green areas and certain streets in order to avoid disturbing the surrounding area.

Type C trenches (where cable connections are laid in a slightly deeper trench) are used in agricultural areas. Aside from its depth, a type C trench is identical to the other types of trench.


Elia always takes its surroundings into account in its work. The high-voltage system operator takes a range of measures intended to minimise disruption and impact on the surrounding area.

  • Work only takes place during the day, from 7 a.m. to 7 p.m.
  • Once work is complete, the land is always restored to its original state.
  • Elia guarantees that local residents will always be able to access their home on foot.
  • In the event of specific, temporarily increased disruption for residents, Elia or its subcontractor(s) will always notify those affected individually via letter.
  • When diversions are required for normal traffic, this is arranged with the road authority and clearly communicated to residents.


If you have any questions or would like more information, please call the free hotline on 0800 11 089 or send an email to omwonenden@elia.be.