Bowbridge Bridge breakthrough

Some news and history on Bowbridge Bridge

Bowbridge Bridge crosses the Thames & Severn Canal at the foot of Butterow Hill, Stroud. Gloucestershire County Council Highways contractor Amey plc recently commenced exploratory work beneath the carriageway widened in the 1960’s.This work will be followed by the reopening of the navigation channel beneath.

An enthusiasm for history

The project will be led by David Goodman of Amey plc, pictured right.

David described his enthusiasm for his work saying, “I love canals, and live close to the Wilts and Berks Canal. It is the civil engineering history I enjoy. It is so interesting to see how people built these structures so well, so long ago.”

Recent history

The monochrome picture below takes us back to 1910. The gentleman in the straw hat is facing towards Stroud as he leans on the canalside fence with the western face of the bridge behind him.

This view reveals that the bridge, built in the 1780’s, spanned the canal and the River Frome. The two watercourses are divided by a well-used narrow towpath.

(1910 photograph below from Stroudwater and Thames & Severn Canal in Old Pictures, by kind permission of Edwin Cuss and Mike Mills)

Road/Bridge Widening

In the 1960’s, when the canal had become derelict, there was clearly a pressing need to widen the roadway to accommodate increased motor traffic up and down Butterow Hill. This was achieved by simply placing two concrete pipes in the bed of the canal to carry whatever flow of water remained. Hundreds of tons of gravel ballast were then tipped into the canal channel immediately adjacent to the bridge. The widened roadway was then built on top of the infill and tight against the face of the canal bridge. A concrete block wall had been built beneath the bridge arch to support the ballast infill.

1960's services

Sewer, gas and mains water pipes were laid beneath the widened road surface.
It is this uncharted network of pipes and cables that the Amey team are currently revealing in a very delicate manner. This work has also involved the removal of just a few of the concrete blocks at the top of the arch — Hence the optimistic headline 'Bowbridge Bridge breakthrough'.
The second picture shows the view of the bridge from the narrow towpath as it appears in 2015. The 1960’s concrete block retaining wall and the recent, albeit small, ‘breakthrough’ appears in the third picture.

 

Next steps in the New Year

Between January and May 2016 the infill will be removed allowing a reinforced concrete box-culvert to be cast on site. The box-culvert will be placed tight against the original bridge arch. The restored navigable canal will flow through it.

The second towpath view, pictured below, shows the bridge and its overgrown infill.

David Goodman adds, "The steep steps on this side of the bridge will be replaced by a slope that will be angled to the left and up to the road level."

Concrete block 'breakthrough'

The 1960’s concrete block retaining wall and the recent, albeit small, ‘breakthrough’ appears in the third picture.

Canalside community under construction

Gloucester based developer Newland Homes have started work on the creation of a new canalside community — Bowbridge Wharf. The development is being built between the line of the canal and Butterow Hill which rises behind it.

The preparatory work for the Newland Homes project involved the stabilisation of the road and roadside bank on Butterow Hill. This has been achieved through a process known as 'soil nailing'. Soil nailing is a construction technique used to stabilise natural soil slopes. The process consists of installing closely spaced bars deep into the slope. The bars are then grouted into place.

Newland Homes have been working with utility companies to move service pipes & cables while keeping a watching brief over works within the road prior to the soil nailing taking place.

Butterow Hill closed

Consequently, Butterow Hill has been closed to traffic whilst the work has been carried out. The original closure notice authorised by Gloucestershire County Council allowed the road to be closed from 7th September to 27th November, or, ‘Until the works were completed’.

Delays caused by gas main leak discovery

During the works an historic leak in the gas main was discovered. This obviously needed urgent attention. Rather than complete the original works and have Wales & West Utilities (W&WU) return with major disruption and further repairs in January, W&WU has repaired the leak whilst the road was being excavated. In the long term this has saved time and future inconvenience.

However, since discovering the gas issue, Newland Homes’ contractors have had to follow stringent procedures when working alongside the gas infrastructure resulting in further delay to progress.

Community consultation & co-operation assists local school

As part of the road closure, Newland Homes funded a mini bus to take local children to school. This followed consultation with the local authority when it was highlighted that the normal bus route was disrupted by the road works.

Here is the good news…

Butterow Hill is set to reopen by 18th December!

Traffic lights will assist the flow across the narrowed bridge.