Good afternoon, Camilla.
Thank you for writing to our Chief Executive, Jeremy Westlake, about the repair works at Chapel Milton Viaduct. My name is Jake Kelly and I am responding as managing director for the North West and Central area.
From my own experience, swifts are magnificent birds and I personally value sustaining and building natural habitats for them.
As Network Rail, we recognise that the viaduct has historically been an important site for swift activity, and like you we hugely value the diversity of wildlife that inhabits railway land. We understand how much these special birds mean to the local community, and I want to take this opportunity to set out clearly what we did, why we did it, and what we intend to do next.
The works and why they were necessary
Our repairs to Chapel Milton Viaduct were essential structural works to ensure the continued safe operation of the railway. The viaduct carries heavy freight trains that support both the regional and national economy, and certain structural cracks and crevices within the masonry had to be filled on safety grounds as part of the approved remedial design.
The ecological surveys we carried out
We want to reassure you that Network Rail took the welfare of swifts at this location extremely seriously throughout the project. Although swifts have been observed flying in the general area of the viaduct, our independent ecological surveys which went beyond what we were legally required to undertake during nesting season did not find evidence of active nesting in the specific areas where the structural works were carried out.
Our survey programme included:
Two preliminary ecological appraisals covering the structure and the compound area
A dawn-to-dusk thermographic imaging survey, during which swifts were observed in the general vicinity but were not found to be entering or exiting span three of the viaduct
Endoscopic surveys carried out by rope access specialists in June and July 2025 at the height of the nesting season which examined the specific crevices in question and found no evidence of active nesting
The ecological procedures we followed
Throughout the works, the project team followed agreed ecological protection procedures, including thorough pre-work checks carried out on the morning of the works to confirm no birds were present before any activity commenced. Works were deliberately programmed to take place outside the nesting season to ensure no disturbance to nesting birds.
These measures reflect our genuine commitment to protecting wildlife on and around the railway, not simply our legal obligations.
What we plan to do next
Whilst we are confident that we followed the correct procedures throughout, we recognise the strength of feeling in the local community and share a genuine commitment to supporting swift conservation at this historic structure.
With that in mind, we are planning to install swift-specific bird boxes on the viaduct to further enhance biodiversity and provide additional nesting opportunities for returning swifts. We are currently seeking advice from Historic England on whether this can be achieved within the constraints of the structure's Grade II listed status. Listed Building Consent is not guaranteed, but we are committed to exploring every available option and will progress this as quickly as possible.
Subject to receiving the necessary permissions, we are very keen to work collaboratively with local conservation groups on the installation of these boxes, and we will be in touch with them directly to discuss this in due course.
We hope this letter demonstrates that Network Rail does not take its responsibilities to wildlife lightly. We carried out surveys that went beyond our legal requirements, we programmed works to avoid the nesting season, we followed our ecological protection procedures throughout, and we are now actively looking at ways to further enhance swift nesting opportunities at the structure.
Thank you for raising this important issue with us, I hope I’ve shown that we always strive to balance the safe running of trains with protecting biodiversity on our land.
Yours sincerely,
Jake Kelly
Regional director for North West and Central
