A720 Sheriffhall Roundabout
The Sheriffhall Roundabout is currently the only junction on the A720 Edinburgh City Bypass that isn't grade separated, which means the main City Bypass is at the same level as the local approach roads. This at-grade, six-way junction often experiences significant queuing, especially during peak hours.
The junction connects six A-roads:
- A7 North
- A6106 Millerhill Road
- A720 East
- A6106 Old Dalkeith Road
- A7 South
- A720 West
Further junction improvements at Sheriffhall were identified as part of the Strategic Transport Projects Review (STPR). The project, which is currently at the early stage in the design and assessment process, will result in separating local traffic from the strategic traffic on the A720 Edinburgh City Bypass and will allow traffic on the bypass to flow freely, improving road safety and journey times for all road users.
Previous improvement works at Sheriffhall have included widening and the provision of additional lanes.
Working on the Sheriffhall Roundabout presents some unique design challenges. The area sits on top of historical mine workings and a geological fault with possible mineral seams, fault zones and mine shafts. Although mining in the area has long ceased, any work done here still needs to take account of these complex ground conditions.
There are also extensive plans for residential and business developments in the region, including the South East Wedge development.
The Borders Railway is also very close, passing beneath the City Bypass via a tunnel 300m east of the Sherriffhall Roundabout.
DMRB Stage 1 Assessment
The Design Manual for Roads and Bridges (DMRB) Stage 1 design Assessment began in June 2013. Transport Scotland appointed Consulting Engineers, AECOM to undertake the design and assessment work.
The principal aim of Stage 1 was to identify a range of grade separation improvement options. The study examined traffic flows and considered how a new grade separated junction would interact with the adjacent A720 junctions.
Eight junction options were reviewed in accordance with the Stage 1 Assessment processes, namely:
- Option 1 – Dumbbell Grade Separation at Sheriffhall
- Option 2 – All slips provided at Gilmerton, no connection at Sheriffhall
- Option 3 – Squareabout at Gilmerton, A7 bridged over A720
- Option 4 – Collector Distributor, No Connection at Sheriffhall
- Option 5 – Combined Gilmerton and Sheriffhall Junction
- Option 6 – Grade Separated Roundabout at Sheriffhall
- Option 7 – Dumbbell Grade Separation at Sheriffhall, Gilmerton Slips closed
- Option 8 – Dumbbell Grade Separation West of Sheriffhall, Gilmerton Slips closed
Stage 1 is complete and concluded that Options 1, 2, 6 and 8 be taken forward for further assessment at Stage 2.
- Stage 2 (options assessment) involved:
- traffic surveys
- traffic modelling including accounting for future transport growth
- ground condition studies
- environmental consideration
A further sifting exercise undertaken during Stage 2 removed option 2.
For simplicity the remaining options 1, 6 and 8 were re-named A, B and C respectively and these emerging options were presented at the Public exhibition in December 2016 (see below).
The Stage 2 assessment is now complete and has identified that Option B is the preferred option. This option is being taken forward to the more detailed assessment during DMRB Stage 3.
A public exhibition was held in December 2016 to present the various options under consideration to the local community and provide an opportunity for vital feedback. You can view the leaflets, drawings and exhibition boards below.
Public exhibition - December 2016
We continue to progress Stage 3 of the development and assessment process to grade separate the Sheriffhall roundabout. This will culminate in the publication of draft Orders for formal comment.