Investigation reveals concerning fact about highway authority: ‘Unfortunately, this seems to be a low priority’

A citizen's request to access information related to the inspection of runoff ponds and other interceptors, including gullies, alongside motorways in the United Kingdom revealed a concerning gap in coverage -- raising fears of toxic contamination.

What's happening?

The New Civil Engineer reported [1] in February that a member of the public obtained access to National Highways data under the Freedom of Information Act, which guarantees the right [2] to see information held by public authorities upon request. They relayed their findings to NCE. The information revealed seven Greater Manchester interceptors around motorways hadn't been inspected or maintained since 2007 despite the fact that separator systems are ideally serviced at least every six months, per environmental consultancy Adler & Allan.

"Although this isn't a mandatory standard in the U.K., it is recognized good practice and should be reflected in National Highways' own maintenance schedules," said Jo Bradley, director of operations at the nonprofit Stormwater Shepherds [3], which aims to ensure future generations have access to clean water. All in all, records showed that 37 interceptors in Rochdale, Manchester, Bury, Tameside, Stockport, and Trafford hadn't been inspected or cleaned since at least 2018.

Why is this concerning?

Interceptors collect road runoff such as fuel, oil, brake fluid, pieces of tires, and elements from deteriorating road surfaces. When they don't receive proper maintenance, hazardous materials -- including microplastics from tires [4] -- can build up before making their way into crucial streams, rivers, and other waterways that serve the general public [5].

"It's increasingly clear that ... our rivers and waters courses are also in a poor state due to pollution flowing off the nation's roads and verges," said Friends of the Earth nature campaigner Paul de Zylva. "... Over time, these pollutants get blown and washed into rivers and waterways near to roads, where they're carried far and wide.

Unfortunately, this seems to be a low priority for our highways authorities and the Environment Agency, as the lack of inspections reflect." For its part, when it responded to the request for data, National Highways asserted that "the runoff ponds with inspections dating between 2007-2012 are likely to have been inspected since, but our records are unable to verify this," per NCE [6]. However, Bradley told the outlet that a visit to several interceptors along junctions 6 and 7 on M60 appeared to tell a different story.

"You know that they haven't been emptied for 15 years; we can see that because we can see that the trees have grown up around the manholes and around the device," Bradley said.

What's being done about this?

A National Highways spokesperson told [7] NCE that the agency is "committed to improving water quality" and aiming to "address all our high-risk outfalls by 2030," with annual inspections on interceptors for 2025-26 and reactive maintenance.

If it successfully executes the plan, it would move the needle in a positive direction, even if it doesn't fulfill the ideal six-month mark.

As a technical partner, professional services consultancy WSP will work closely [8] with National Highways and other program partners Mott Macdonald, Ramboll, and AECOM to verify high-risk assets and develop a strategy to mitigate risks and improve water quality as well as protect vulnerable wildlife that depend on the area's natural resources for survival [9].

Join our free newsletter [10] for good news and useful tips, and don't miss this cool list [11] of easy ways to help yourself while helping the planet.

Cool Picks

References

^ reported (www.newcivilengineer.com)
^ guarantees the right (www.gov.uk)
^ Stormwater Shepherds (www.stormwatershepherds.org.au)
^ microplastics from tires (www.thecooldown.com)
^ serve the general public (guide.thecooldown.com)
^ NCE (www.newcivilengineer.com)
^ told (www.newcivilengineer.com)
^ will work closely (www.wsp.com)
^ natural resources for survival (www.wsp.com)
^ free newsletter (www.thecooldown.com)
^ this cool list (rb.gy)