A40 Clockwise Jct Denham Roundabout Lane 2 closure

Planned

Start time: Sat, Mar 7, 2026 10:00 PM
Expected end: Sun, Mar 8, 2026 6:00 AM
Duration: 8 hours
Road: A40 – Roundabout At M40 J1/A40
Category: Road Maintenance
Direction: Clockwise
Carriageway: Dual Carriageway
Lanes affected: 2 of 2 lanes affected
Reason: Roadworks

Active

Planned

Cleared

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First published: Wed, Mar 4, 2026 2:50 PM
Last updated: Sat, Mar 7, 2026 11:59 PM
Cleared: Sun, Mar 8, 2026 6:00 AM

Latest update: A40 Clockwise Jct Denham Roundabout Lane 2 closure

Coordinates: 51.562281, -0.497920
Latitude span: 51.562012 – 51.562612
Longitude span: -0.498244 – -0.497560
Bounding box centre: 51.562312, -0.497902
Location descriptions: roundabout at M40 J1/A40

Feed validity status: Planned
Overall feed start: Sat, Mar 7, 2026 10:00 PM
Overall feed end: Sun, Mar 8, 2026 6:00 AM
Feed window length: 8 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

3 coordinate pairs

Description: roundabout at M40 J1/A40
Carriageway: Dual Carriageway
Lanes Restricted: 2 lanes 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: {43F990DC-B3EF-44C8-851B-491F68920039}
Linear Element Type: Other
From Distance: 0 m
To Distance: 24 m
Gml Srs Name: EPSG::4326
Gml Srs Dimension: 2

Raw coordinate list

51.562422 -0.497724
51.562588 -0.49757
51.562612 -0.49756

Segment 2

2 coordinate pairs

Description: roundabout at M40 J1/A40
Carriageway: Dual Carriageway
Lanes Restricted: 2 lanes 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: {A2317FCF-EDCE-47B6-B43B-F489D7D70C5C}
Linear Element Type: Other
From Distance: 0 m
To Distance: 11 m
Gml Srs Name: EPSG::4326
Gml Srs Dimension: 2

Raw coordinate list

51.562051 -0.498215
51.562121 -0.498097

Segment 3

4 coordinate pairs

Description: roundabout at M40 J1/A40
Carriageway: Single Carriageway
Lanes Restricted: 2 lanes restricted
Operational Lanes: 2 operational lanes
Direction On Section: Clockwise
Direction Relative: Both
Height Grade: Start1 End1
Linear Element Road: A40
Linear Element Model: The Network Model
Linear Element Id: {05C9EE3B-D4CB-4D71-A07C-33CE63B9DD3D}
Linear Element Type: Other
From Distance: 0 m
To Distance: 42 m
Gml Srs Name: EPSG::4326
Gml Srs Dimension: 2

Raw coordinate list

51.562121 -0.498097
51.562325 -0.49786
51.562361 -0.49781
51.562422 -0.497724

Segment 4

2 coordinate pairs

Description: roundabout at M40 J1/A40
Carriageway: Dual Carriageway
Lanes Restricted: 2 lanes 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: {7E3245F9-FDA3-44ED-A204-D956D43713DC}
Linear Element Type: Other
From Distance: 17 m
To Distance: 22 m
Gml Srs Name: EPSG::4326
Gml Srs Dimension: 2

Raw coordinate list

51.562012 -0.498244
51.562051 -0.498215

Geometry type: MultiLineString
Geometry points: 11
First coordinate pair: -0.497724, 51.562422
Road section segments: 1
Road section points: 11

View geometry JSON

{
    "type": "MultiLineString",
    "coordinates": [
        [
            [
                -0.497724,
                51.562422
            ],
            [
                -0.49757,
                51.562588
            ],
            [
                -0.49756,
                51.562612
            ],
            [
                -0.498215,
                51.562051
            ],
            [
                -0.498097,
                51.562121
            ],
            [
                -0.498097,
                51.562121
            ],
            [
                -0.49786,
                51.562325
            ],
            [
                -0.49781,
                51.562361
            ],
            [
                -0.497724,
                51.562422
            ],
            [
                -0.498244,
                51.562012
            ],
            [
                -0.498215,
                51.562051
            ]
        ]
    ]
}

View road section coordinates

Cause type: Road Maintenance
Detailed cause: Roadworks
Compliance: Mandatory
Probability: Probable
Validity status: Planned
Road management: Other