HS2 Solihull viaducts complete: 495m River Blythe span

The three HS2 viaducts that carry the new railway across Solihull borough are now structurally complete. HS2 confirmed on 12 August that the River Blythe, Balsall Common and Marsh Farm viaducts, all of them between Hampton in Arden and Balsall Common on the southern approach to Interchange station, have reached structural completion, with the final parapets going on to the River Blythe viaduct in the coming days. (HS2 media centre, 12 August 2026)

The three are very different structures. River Blythe is the largest and the closest to Interchange station, about 1.5 miles away: 495 metres long and 12 metres high, crossing the river, its floodplain and Meriden Road near Hampton in Arden. Balsall Common is 430 metres long and eight metres high, built to the north-east of the existing Network Rail line and crossing Station Road, Truggist Lane, Bayleys Brook, the Heart of England Way and the floodplain. Marsh Farm, two and a half miles south of the River Blythe crossing, is the smallest at 145 metres long and five metres high, carrying the main line over Bayleys Brook and the marshland around it.

The River Blythe crossing was built around an SSSI

The River Blythe is a Site of Special Scientific Interest, and HS2 says the design was shaped by that. The low-lying structure is carried on two abutments and 19 concrete piers with Y-shaped splits, a form HS2 says reduces the volume of concrete used as well as changing how the viaduct looks. The space beneath is designed to let wildlife through, with dispersal routes cited for badgers, bats, birds, fish, great crested newts, otters and water voles.

The parapets are polished concrete and acoustic, which HS2 says both cuts noise for nearby homes and visually reduces the mass of the structure. Local residents opted for the larger polished parapets on one side and were consulted on the tree planting meant to settle the viaduct into the landscape. Structural completion is not the end of the work here: engineers still have acoustic barriers to fit and final waterproofing to do.

Doug Barnett, HS2 Ltd’s senior project manager, said the design and landscaping solutions “were of upmost importance to local residents, and we worked extremely hard to get that right”.

Balsall Common’s parapets were chosen by public vote

At Balsall Common the main structure was finished earlier this year, and the parapets are the part still to be installed. Their design came out of a public vote: a polished finish that reflects the sky and surrounding vegetation, and a weave motif referencing the area’s history of textile production. HS2 says all 304 parapets will be installed by spring 2027.

Both the Balsall Common and River Blythe structures were classed as Key Design Elements, HS2’s label for structures whose size, closeness to communities or location in a sensitive area meant local people were given a say in how they look.

Building over Bayleys Brook meant moving it. Matthew Parkes, construction manager at HS2’s contractor Balfour Beatty VINCI, said engineers “carefully diverted a 150-metre section of the brook to allow Balsall Common Viaduct to pass over the top”.

What it means for you

Work is not finished in Balsall Common. Parapet installation runs on to spring 2027, so construction activity around Station Road and Truggist Lane continues. If you drive or walk those routes, check current restrictions before you set out; our Solihull roadworks and travel page covers where to look for live closures.

Marsh Farm viaduct is doing a second job. HS2 says the finished structure is being used as a haul road while the embankments and cuttings beside it are built, and that this keeps lorries off local roads. So a completed viaduct still carrying construction traffic is expected, not a sign of a problem.

Walkers on the Heart of England Way should expect the long-distance path to pass under the Balsall Common structure permanently. The viaduct crosses the route.

None of this puts a date on trains. The release gives no opening date for Interchange station or for services, and we are not going to invent one. What HS2 does say is that passengers from Interchange will be able to reach London Euston and Old Oak Common, which it describes as directly linked to more than 100 locations. Until then, the fastest way to London from the borough is the existing service, which we set out on our Solihull train times to London page.

For scale, HS2 says the whole route has more than 500 bridging structures, including over 50 major viaducts stretching a combined 15 kilometres, or nine miles. Three of them are ours.

Also this week: Solihull’s T Level results, and what the numbers behind them show.