Crash View

A4020 Oxford Road to A40 Denham Roundabout Westbound Jct 1 Exit Slip Lane 2 Closure

Planned

A4020 Oxford Road to A40 Denham Roundabout Westbound Jct 1 Exit Slip Lane 2 Closure

Start time
Mon, Oct 12, 2026 9:00 PM
Expected end
Tue, Oct 13, 2026 4:00 AM
Duration
7 hours
Road
A40 – Roundabout At M40 J1/A40
Category
Road Maintenance
Direction
Southbound
Carriageway
Dual Carriageway
Lanes affected
Lane 2 closed, 1 of 1 lanes affected, 1 of 3 lanes affected
Reason
Maintenance Work
Live incident
Active roadworks
Planned
Cleared
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First published
Mon, Oct 12, 2026 1:43 PM
Last updated
Mon, Oct 12, 2026 5:35 PM
Cleared
Tue, Oct 13, 2026 4:00 AM
  • Latest update: A4020 Oxford Road to A40 Denham Roundabout Westbound Jct 1 Exit Slip Lane 2 Closure
Coordinates
51.560592, -0.493324
Latitude span
51.560003 – 51.561156
Longitude span
-0.493895 – -0.493095
Bounding box centre
51.560580, -0.493495
Location descriptions
  • roundabout at M40 J1/A40
Feed validity status
Planned
Overall feed start
Mon, Oct 12, 2026 9:00 PM
Overall feed end
Tue, Oct 13, 2026 4:00 AM
Feed window length
7 hours
Probability code (raw)
probable
Compliance option (raw)
mandatory
Source identification (raw)
roadworks
Management type value
other
Contra-flow flag (raw)
false
Width restriction flag (raw)
false
Height restriction flag (raw)
false
Weight restriction flag (raw)
false

Segment 1

2 coordinate pairs
Description
roundabout at M40 J1/A40
Carriageway
Dual Carriageway
Lane Usage
Cl2
Lane Number
2
Lane Status
Closed
Lane Direction
Aligned
Lanes Restricted
1 lane restricted
Operational Lanes
0 operational lanes
Direction On Section
South Bound
Direction Relative
Aligned
Height Grade
Start1 End1
Linear Element Road
A40
Linear Element Model
The Network Model
Linear Element Id
{1C6646EB-9EFE-43A3-A1D7-05AA5E400D7F}
Linear Element Type
Other
From Distance
0 m
To Distance
17 m
Gml Srs Name
EPSG::4326
Gml Srs Dimension
2
Raw coordinate list 
51.560699 -0.493095
51.560555 -0.493182

Segment 2

4 coordinate pairs
Description
roundabout at M40 J1/A40
Carriageway
Single Carriageway
Lane Usage
Cl2
Lane Number
2
Lane Status
Closed
Lane Direction
Aligned
Lanes Restricted
1 lane restricted
Operational Lanes
1 operational lane
Direction On Section
Clockwise
Direction Relative
Both
Height Grade
Start1 End1
Linear Element Road
A40
Linear Element Model
The Network Model
Linear Element Id
{F9FC075C-0770-42B3-AF17-081B01B622D4}
Linear Element Type
Other
From Distance
0 m
To Distance
25 m
Gml Srs Name
EPSG::4326
Gml Srs Dimension
2
Raw coordinate list 
51.5605 -0.493267
51.560432 -0.493332
51.560332 -0.49344
51.560306 -0.493472

Segment 3

2 coordinate pairs
Description
roundabout at M40 J1/A40
Carriageway
Dual Carriageway
Lane Usage
Cl2
Lane Number
2
Lane Status
Closed
Lane Direction
Aligned
Lanes Restricted
1 lane restricted
Operational Lanes
3 operational lanes
Direction On Section
West Bound
Direction Relative
Aligned
Height Grade
Start1 End1
Linear Element Road
A40
Linear Element Model
The Network Model
Linear Element Id
{D8C291F3-6C0D-41FD-8852-F59F4A42EEFD}
Linear Element Type
Other
From Distance
0 m
To Distance
10 m
Gml Srs Name
EPSG::4326
Gml Srs Dimension
2
Raw coordinate list 
51.560088 -0.493822
51.560003 -0.493895

Segment 4

2 coordinate pairs
Description
roundabout at M40 J1/A40
Carriageway
Single Carriageway
Lane Usage
Cl2
Lane Number
2
Lane Status
Closed
Lane Direction
Aligned
Lanes Restricted
1 lane restricted
Operational Lanes
1 operational lane
Direction On Section
Clockwise
Direction Relative
Both
Height Grade
Start1 End1
Linear Element Road
A40
Linear Element Model
The Network Model
Linear Element Id
{68F8FADF-37D0-4824-83FD-A65EAA260780}
Linear Element Type
Other
From Distance
0 m
To Distance
18 m
Gml Srs Name
EPSG::4326
Gml Srs Dimension
2
Raw coordinate list 
51.561114 -0.493182
51.560952 -0.493158

Segment 5

4 coordinate pairs
Description
roundabout at M40 J1/A40
Carriageway
Single Carriageway
Lane Usage
Cl2
Lane Number
2
Lane Status
Closed
Lane Direction
Aligned
Lanes Restricted
1 lane restricted
Operational Lanes
1 operational lane
Direction On Section
Clockwise
Direction Relative
Both
Height Grade
Start1 End1
Linear Element Road
A40
Linear Element Model
The Network Model
Linear Element Id
{8754CD64-54A3-4623-AE20-977C625E4BF4}
Linear Element Type
Other
From Distance
0 m
To Distance
34 m
Gml Srs Name
EPSG::4326
Gml Srs Dimension
2
Raw coordinate list 
51.560306 -0.493472
51.560273 -0.493513
51.560211 -0.493587
51.560088 -0.493822

Segment 6

2 coordinate pairs
Description
roundabout at M40 J1/A40
Carriageway
Single Carriageway
Lane Usage
Cl2
Lane Number
2
Lane Status
Closed
Lane Direction
Aligned
Lanes Restricted
1 lane restricted
Operational Lanes
1 operational lane
Direction On Section
Clockwise
Direction Relative
Both
Height Grade
Start1 End1
Linear Element Road
A40
Linear Element Model
The Network Model
Linear Element Id
{B8CD81A6-B542-4B36-85A8-3706D989AD6A}
Linear Element Type
Other
From Distance
4 m
To Distance
9 m
Gml Srs Name
EPSG::4326
Gml Srs Dimension
2
Raw coordinate list 
51.561156 -0.493195
51.561114 -0.493182

Segment 7

4 coordinate pairs
Description
roundabout at M40 J1/A40
Carriageway
Dual Carriageway
Lane Usage
Cl2
Lane Number
2
Lane Status
Closed
Lane Direction
Aligned
Lanes Restricted
1 lane restricted
Operational Lanes
0 operational lanes
Direction On Section
Clockwise
Direction Relative
Aligned
Height Grade
Start1 End1
Linear Element Road
A40
Linear Element Model
The Network Model
Linear Element Id
{0ADD6897-E733-4876-B914-5C7C075721CB}
Linear Element Type
Other
From Distance
0 m
To Distance
19 m
Gml Srs Name
EPSG::4326
Gml Srs Dimension
2
Raw coordinate list 
51.560869 -0.493133
51.560824 -0.493095
51.560816 -0.493095
51.560699 -0.493095

Segment 8

2 coordinate pairs
Description
roundabout at M40 J1/A40
Carriageway
Single Carriageway
Lane Usage
Cl2
Lane Number
2
Lane Status
Closed
Lane Direction
Aligned
Lanes Restricted
1 lane restricted
Operational Lanes
1 operational lane
Direction On Section
Clockwise
Direction Relative
Both
Height Grade
Start1 End1
Linear Element Road
A40
Linear Element Model
The Network Model
Linear Element Id
{2ECD94C7-03F6-4ADB-84CF-562BD531968C}
Linear Element Type
Other
From Distance
0 m
To Distance
9 m
Gml Srs Name
EPSG::4326
Gml Srs Dimension
2
Raw coordinate list 
51.560952 -0.493158
51.560869 -0.493133

Segment 9

2 coordinate pairs
Description
roundabout at M40 J1/A40
Carriageway
Dual Carriageway
Lane Usage
Cl2
Lane Number
2
Lane Status
Closed
Lane Direction
Aligned
Lanes Restricted
1 lane restricted
Operational Lanes
0 operational lanes
Direction On Section
South Bound
Direction Relative
Aligned
Height Grade
Start1 End1
Linear Element Road
A40
Linear Element Model
The Network Model
Linear Element Id
{3DF5FF34-7930-43BB-B5D6-DAF4E7EB173D}
Linear Element Type
Other
From Distance
0 m
To Distance
8 m
Gml Srs Name
EPSG::4326
Gml Srs Dimension
2
Raw coordinate list 
51.560555 -0.493182
51.5605 -0.493267
Geometry type
MultiLineString
Geometry points
24
First coordinate pair
-0.493095, 51.560699
Road section segments
1
Road section points
24
View geometry JSON 
{
    "type": "MultiLineString",
    "coordinates": [
        [
            [
                -0.493095,
                51.560699
            ],
            [
                -0.493182,
                51.560555
            ],
            [
                -0.493267,
                51.5605
            ],
            [
                -0.493332,
                51.560432
            ],
            [
                -0.49344,
                51.560332
            ],
            [
                -0.493472,
                51.560306
            ],
            [
                -0.493822,
                51.560088
            ],
            [
                -0.493895,
                51.560003
            ],
            [
                -0.493182,
                51.561114
            ],
            [
                -0.493158,
                51.560952
            ],
            [
                -0.493472,
                51.560306
            ],
            [
                -0.493513,
                51.560273
            ],
            [
                -0.493587,
                51.560211
            ],
            [
                -0.493822,
                51.560088
            ],
            [
                -0.493195,
                51.561156
            ],
            [
                -0.493182,
                51.561114
            ],
            [
                -0.493133,
                51.560869
            ],
            [
                -0.493095,
                51.560824
            ],
            [
                -0.493095,
                51.560816
            ],
            [
                -0.493095,
                51.560699
            ],
            [
                -0.493158,
                51.560952
            ],
            [
                -0.493133,
                51.560869
            ],
            [
                -0.493182,
                51.560555
            ],
            [
                -0.493267,
                51.5605
            ]
        ]
    ]
}
View road section coordinates 
[
    [
        [
            -0.493095,
            51.560699
        ],
        [
            -0.493182,
            51.560555
        ],
        [
            -0.493267,
            51.5605
        ],
        [
            -0.493332,
            51.560432
        ],
        [
            -0.49344,
            51.560332
        ],
        [
            -0.493472,
            51.560306
        ],
        [
            -0.493822,
            51.560088
        ],
        [
            -0.493895,
            51.560003
        ],
        [
            -0.493182,
            51.561114
        ],
        [
            -0.493158,
            51.560952
        ],
        [
            -0.493472,
            51.560306
        ],
        [
            -0.493513,
            51.560273
        ],
        [
            -0.493587,
            51.560211
        ],
        [
            -0.493822,
            51.560088
        ],
        [
            -0.493195,
            51.561156
        ],
        [
            -0.493182,
            51.561114
        ],
        [
            -0.493133,
            51.560869
        ],
        [
            -0.493095,
            51.560824
        ],
        [
            -0.493095,
            51.560816
        ],
        [
            -0.493095,
            51.560699
        ],
        [
            -0.493158,
            51.560952
        ],
        [
            -0.493133,
            51.560869
        ],
        [
            -0.493182,
            51.560555
        ],
        [
            -0.493267,
            51.5605
        ]
    ]
]
Cause type
Road Maintenance
Detailed cause
Maintenance Work
Compliance
Mandatory
Probability
Probable
Validity status
Planned
Road management
Other
Feed provider
National Highways
Data source
Roadworks
Feed version
1
Record created
Mon, Oct 12, 2026 1:43 PM
Record versioned
Mon, Oct 12, 2026 5:35 PM
Coordinate source
Geometry

Driving on the A40? See every live closure, roadwork and planned restriction on this road.

A40 live closures

Related incidents

A40 Eastbound Jct 1 exit slip road lane 1 closure

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