Johnstonebridge Interchange

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Johnstonebridge Interchange
Location Map ( geo)
M74, Junction 16 - Geograph - 2683163.jpg
The Southbound Fork Sign in October 2011
Cameraicon.png View gallery (2)
Location
Johnstonebridge
County
Dumfriesshire
Highway Authority
Transport Scotland
Junction Type
Dumbbell
Roads Joined
A74(M), B7076
Junctions related to the B7076
Beattock Interchange • Crawford and Elvanfoot Interchanges • Gretna Interchange • Guards Mill Interchange • Kirkpatrick Fleming Interchange

Junction 16 on the A74(M), which marks the southern end of the last and longest rural section of the M74/A74(M) to be built, is a dumbbell. To the west is a link to the B7076 (the remains of the former dualled A74) and to the east is the entrance to Annandale Water services.

The motorway and the ex-A74 are parallel, running due north-south, and at the same level. The service area is at a lower level as the land falls eastward to the River Annan. The junction roundabouts are at the same level as the service area, so the link road has to climb in order to tie in with the B7076. To fit the climb into the space available, two right-angle curves are required.

The southbound exit slip road starts considerably further north than would seem necessary. This seems to have been a design change after the main part of the junction was open, and the reason for it is entirely mysterious.

The junction bridge is the watershed for the numbering of marker posts on the A74(M). To the south, they use the same London-based system as the M6 and M1. To the north, they use the same Glasgow-based system as the M74.

History

When the A74(M) was being built, this junction was a major temporary terminus of the motorway, and was then always referred to as Cleuchbrae. This name is that of a farm on the west side of the ex-A74 half a mile north of the junction, and of an adjacent burn.

When the junction was completed in its original form in December 1994, the motorway from the south, some distance after passing over the junction bridge and just before what is now its meeting with the northbound on-slip, curved to the left and then right to tie in with the A74 at Cleuchbrae.

The two southern slip roads were opened at that time. A version of the southbound off-slip was also opened; its southern part was as now, while its northern part was sharply curved. The northbound on-slip was left in an unfinished state, with earthworks, drainage and fencing complete for most of its length, but cut off at the north end by the temporary mainline, and with no carriageway construction done. Traffic wishing to join the northbound A74 would use the ex-A74 which had a temporary merge at Cleuchbrae.

A cutting was also made at that time through the hill to the north of the junction, ready for the next stretch of A74(M) northward. As with the northbound on-slip, its bulk earthworks, drainage and fencing were completed, but no carriageway construction was done. It may be that this cutting was not originally part of the contract but that the contractor was in need of fill for use further south, and thought of this as an excellent way to get it.

If we assume that this cutting was shaped in accordance with the design, as it then stood, of the future motorway, it can be said that the permanent southbound off-slip was originally planned to be of similar length to the northbound on-slip. When the next section northward came to be built, the cutting was widened on the east side to accommodate the longer slip road that was, for unknown reasons, then built.

The junction was finally completed in its finished form, along with the stretch of motorway northward to Paddy's Rickle Bridge, in April/May 1999.

For further historical background see M74 and A74(M) History.

Routes

Route To Notes

A74(M)

The NORTH, Glasgow, Edinburgh

A74(M)

The SOUTH, Carlisle

B7076

Beattock

B7076

Johnstonebridge, Lockerbie

Annandale Water services

Annandale Water services



Johnstonebridge Interchange
Related Pictures
View gallery (2)
M74, Junction 16 - Geograph - 2683163.jpgM74-16.jpg
Junctions on the M74 & A74(M)
M74M8 (22) Plantation Road • M8 (21) Seaward Street • 1 Kingston • 1A Polmadie Road • 2 Cambuslang Road • 2A Fullarton Road • 3 Carmyle Avenue • 3A Daldowie • 4 Maryville • 5 Raith • 6 Hamilton • 7 Larkhall • 8 Canderside Toll • Draffan • 9 Junction 9 • 10 Wellburn • 11 Poniel • 12 Millbank • 13 Abington
A74(M)13 Abington • 14 (North) Crawford • 14 (South) Elvanfoot • 15 Beattock • 16 Johnstonebridge • 17 Lockerbie North • 18 Lockerbie South • 19 Ecclefechan • 20 Eaglesfield • 21 Kirkpatrick Fleming • 22 Gretna • M6 (45) Guards Mill