Slugs kept shorting Stretford's traffic lights — seals and copper tape ended the outages

The traffic lights at the Robin Hood crossroads in Stretford, Trafford — where Urmstone Lane, Kingsway and Barton Road meet — failed again and again despite being fixed or replaced. The signals were less than a couple of years old, three dangerous incidents were reported in the space of a year, and residents asked why the lights kept going out. Transport for Greater Manchester's engineers were initially baffled.

Trafford councillor Steve Adshead, who had to push Transport for Greater Manchester 'quite a bit', kept at it for more than a year before the authority came back with a written explanation: with the exception of one outage caused by a road traffic collision, every fault shared the same underlying cause. Slugs had entered the signal controller — drawn by warmth — and their bodies caused short circuits. It was, Adshead said, the first time the highways team had ever experienced this.

The remedial works in July 2026 were unglamorous and cheap: checking the controller's door and base seals for holes and sealing them, and installing copper tape around the electrical components. Since the works were completed, Transport for Greater Manchester reported, there have been no further signal outages at the junction.

The outages repeated even after repair and replacement, so the equipment's age was not the cause.

Slugs seeking warmth crawled into the signal controller, and their bodies shorted the circuits.

A councillor kept pressing the authority for over a year until a root-cause explanation arrived in writing.

Sealing closed the entry route and the copper tape guarded the components, without replacing the whole unit.

When an asset keeps failing for no visible reason, push for a real root cause before replacing parts again — and don't dismiss a low-tech fix once the cause is known.

Transport for Greater Manchester set out the diagnosis and the fix in a letter: apart from one collision-caused outage, the faults shared one cause, and the July 2026 remedial works — resealing the controller and adding copper tape — have been followed by no further signal outages. Adshead noted residents had been the ones asking why the lights kept failing, and that the highways team had never seen anything like it before.