Upcoming works at Hackney Substation and Millfields Park
Planned works are now taking place at Hackney Substation and within parts of Millfields Park as part of the North London Reinforcement Project.
These works are taking place from May and will help us carry out important maintenance and upgrades to the electricity network serving North London safely and reliably.
What to expect
Work is currently taking place at Hackney Substation as part of the reinforcement. This includes clearing vegetation within the substation site, conducting ground surveys, and installing temporary ground protection mats to help protect surfaces during the works.
Our work within the substation will take place from 8am to 5pm including some weekends.
Work in Millfields Park
We will soon be carrying out work on our overhead electricity lines within Millfields Park and we will be placing ground protection mats in some areas of the park. We expect to be finished by the end of August.
Working hours are:
Weekdays: 7:30am–6:00pm (Monday to Friday)
Every other weekend:
Saturday: 7:30am–1:00pm
Sunday: 7:30am–3:00pm
Overview
Hackney Substation is an important part of the electricity network in North London. It helps move electricity safely and reliably into London.
We are upgrading the electricity network across North London so it can carry more power safely and reliably. This will help meet growing demand for electricity and support a stronger network for the future.
At Hackney, we need to upgrade equipment inside the substation. Some work is also expected in Millfields Park and nearby streets.
We know Millfields Park is an important local space for residents, park users and the wider community. We carefully plan our work to minimise disruption wherever possible. If any activity is likely to affect access to the park, local roads or nearby homes, we will let local residents know in advance.
What is happening
We plan to upgrade the overhead electricity line between Tottenham Substation and Hackney Substation. This will help the line carry more electricity safely and reliably as demand grows.
We also plan to replace two existing Supergrid Transformers at Hackney Substation. These are large pieces of equipment that help move electricity around the network by changing it to the right voltage.
Before the main work starts, we will need to carry out preparation work. This could include clearing vegetation, putting up fencing, creating temporary access routes and installing scaffolding.
Construction activity
Early site work is now underway at Hackney. This includes ground testing, putting down temporary ground protection mats, delivering welfare cabins and removing smaller pieces of equipment.
Outside the substation, we will also rewire sections of the overhead electricity line between Tottenham and Hackney. Some of this work will take place in Millfields Park.
While overhead line works are taking place, working hours will be 7:30am to 6pm, Monday to Friday. Work will also take place every other weekend, with working hours of 7:30am to 1pm on Saturdays and 7:30am to 3pm on Sundays.
Additional weekend work may also be required at other stages of the project, depending on construction requirements.
Works at Hackney
Our timetable for the work at Hackney is still being developed and may change. We need to plan the work around when parts of the electricity network can safely be taken out of service, when key equipment can be delivered, and other activity across the wider project.
The timeline below is our current estimate and may change:
- Early site works and preparation - Summer 2026
- Overhead line re-wiring – Summer 2026
- Main works begin, including removal of existing equipment – September - October 2026
- Groundworks and construction to prepare for new equipment – Winter 2026
- Installation of first new Supergrid Transformer – 2027
- Installation of second new Supergrid Transformer – 2029
A Supergrid Transformer (SGT) is a large piece of equipment that changes the voltage of electricity. This helps electricity travel efficiently across the network and be delivered safely to homes and businesses.
The existing SGTs at Hackney are being replaced with newer, higher-capacity units. This will help the substation operate at a higher voltage and support a stronger, more reliable electricity network for homes, businesses and communities across North London.
We expect to start removing the existing transformers in autumn 2026. The first replacement transformer is currently expected in 2027, with the second scheduled for 2029. These timings are estimates and may change as the programme develops.
As of May 2026, we are carrying out planned work in parts of Millfields Park to help maintain and upgrade the electricity network that serves North London.
The work includes activity on overhead electricity lines in the park and the use of ground protection mats in some areas to help protect the grass and ground conditions. We currently expect this work to be completed by the end of August.
We have carried out detailed noise assessments to understand how construction may affect the local area. Some work, such as removing existing equipment, groundworks and installing new equipment, may be noticeable at times because it involves heavy machinery. We will carefully plan noisier work to reduce disruption wherever possible.
Construction will usually take place between 7:30am and 6pm, Monday to Friday. During overhead line works, work will also take place every other weekend, from 7:30am to 1pm on Saturdays and 7:30am to 3pm on Sundays.
Occasional additional weekend work may be needed, depending on construction requirements.
If disruptive work needs to take place outside normal hours, we will carefully manage it and let the local community know in advance.
Traffic management
Most construction work in Hackney will not need road closures. A small number of short, planned closures will be needed to deliver the new Supergrid Transformers via Hillstowe Street. We will let the local community know well in advance before these deliveries take place.
Access for overhead line works will also be required via Millfields Road into Millfields Park.
Some work may need temporary traffic management, such as lane restrictions or temporary traffic control. Where this is needed, we will plan it carefully and tell the local community in advance.
Find out more about temporary closures on our Traffic Management page here.
We will keep Public Rights of Way open wherever we can, and most footpaths will remain accessible.
You can find more information about temporary closures on our Traffic Management page.
All heavy equipment for the project will be delivered to and removed from site via Hillstowe Street.
When planning HGV routes, we consider road safety, local access and how to reduce disruption for residents. The highways authority also reviews and approves these routes.
Contractors must use the agreed routes set out in the project’s Traffic Management Plan. Drivers will be briefed before making any journeys, and we will monitor compliance during construction.
If you have any concerns about HGV movements during the project, please contact our community relations team.
We are working closely with Hackney Council Highways to plan vehicle movements and traffic management. The council helps coordinate activity across different projects in the area, so the road network can continue to operate safely. We will continue to work through the right channels to coordinate our plans wherever possible.
Environment
Across the North London Reinforcement project, we aim to improve biodiversity by at least 15%. This means leaving local habitats in a better condition than they were before the work began.
Where possible, we are upgrading existing sites rather than building new ones. We are also looking for opportunities to introduce new planting and habitat improvements to help make the local area greener.
Because some work is taking place in Millfields Park, we are planning it carefully with the park, local environment and community in mind.
We will continue to work with local stakeholders and park users to understand concerns, protect important features such as trees and green spaces wherever possible, and identify ways to support positive outcomes for the community.
We are planning the work carefully to reduce environmental impacts wherever possible. At this stage, no tree removal has been confirmed. If any tree work is needed, we will manage it appropriately and let the local community know in advance.
We do not currently plan to close the park. There may be more construction activity in the park and small areas may need to be temporarily fenced off so work can be carried out safely. If any temporary closures are needed, we will let the local community know in advance.
Security
Security measures will be in place to help keep the site safe and secure. This includes overnight security when the site is not in active use. We may also use secure fencing, lighting and monitoring systems where needed. These measures are designed to protect the site, equipment and surrounding area.
Contact us
If you would like any further information or to speak to a member of the community relations team about the works, please use the contact form on our website or via the contact details below.
Email: [email protected]
Phone: 0800 538 5398