The engineering marvel that is St Saviour’s bridge, Ottery

St Saviour's Bridge in Ottery, a symbol of old-day resilience, has a rich history of reconstruction due to being washed away multiple times, questioning the present location as the original one. However, the bridge was entirely swept away in the great December flood of 1849. Tenders were invited in February 1851, and a decision was made to construct a cast iron bridge to produce the ornate effect of the five Gothic arches, which are such an attractive feature of the bridge and have made residents wonder how they were transported from Leeds to Ottery. A document created on the 10th of July 1992, when St Saviour's Bridge was reopened, provides fascinating insight into the history of the bridge's reconstruction. Thirty-two years later, I have been given the opportunity to share it with you.

In 1851, the 24-metre bridge met the transportation needs of the day's coaches and carts, but by 1991, a carriageway less than five metres wide with a sharp bend was deemed inadequate. Additional government funding was allocated to bring all main route bridges up to standard. Upon inspection, the Council's engineers found cracked cast iron members and a corroded deck at St Saviour's Bridge, requiring immediate repair and reinforcement.

County Engineer Edward Chorlton and his team of bridge engineers faced a unique set of challenges. On one hand, modern traffic necessitated a bridge that adhered to contemporary strength standards. On the other hand, the bridge's status as an Ancient Monument mandated that its outward appearance remained unchanged. Furthermore, as the primary entrance to the town, the bridge couldn't be closed entirely during reconstruction, requiring continued access for vehicles and pedestrians. Dean and Dyball Construction Ltd, with the lowest bid of £330,262, had the formidable task of reconciling all these demands and delivering a bridge equipped for modern highway loading, all while preserving the iconic appearance of the original 1851 bridge.

The reconstruction was a testament to meticulous planning and execution. A temporary footbridge was promptly constructed near the upstream side, while one-way traffic was efficiently maintained with temporary signals. The bridge supported two large-diameter gas mains, three telephone ducts, a water main and a high-voltage electricity cable, necessitating careful planning. Steps were decisively taken on the south side to widen the bridge. A large piling rig efficiently bored 24 cast-in-place concrete piles, each 600mm in diameter and 8 metres deep, to firmly support the abutment extensions and wing walls and prevent differential settlement. The old stonework was meticulously recorded before being promptly taken down, and new reinforced concrete abutments and wing walls were efficiently completed and robustly supported on the piles. The southern cast iron arch was assertively disassembled into three parts by undoing the 141-year-old connecting bolts and moved to its new position at the end of the new abutments. The old bolts were unsparingly reused to reassemble the arch.

The road was completely closed for the installation of the first three new steel beams. Once the new deck was built over these beams, traffic was diverted to it while work continued on the other half of the road. Three more new beams were then placed between the four existing cast iron arches, and a new deck was constructed over them. Rapid-setting concrete was poured between the two halves of the new deck, necessitating another closure to prevent vibration from traffic while the concrete set. Finally, finishing works were completed, and the bridge was reopened for unrestricted two-way traffic.

Next time you drive over this incredible wonder of engineering, remember its uniqueness and message: modernism and technological advancements can work with an ancient monument's status to provide efficient service without sacrificing beauty.