Crash View

A40 Clockwise Jct Denham Roundabout Lane 3 Closure

Planned

A40 Clockwise Jct Denham Roundabout Lane 3 Closure

Start time
Fri, Sep 26, 2025 10:00 PM
Expected end
Sat, Sep 27, 2025 4:00 AM
Duration
6 hours
Road
A40 – Roundabout At M40 J1/A40
Category
Road Maintenance
Direction
Clockwise
Carriageway
Dual Carriageway
Lanes affected
Lane 4 closed, 1 of 1 lanes affected, 1 of 3 lanes affected
Reason
Maintenance Work
Active
Planned
Cleared
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First published
Fri, Sep 26, 2025 10:15 AM
Last updated
Fri, Sep 26, 2025 8:00 PM
Cleared
Sat, Sep 27, 2025 4:00 AM
  • Latest update: A40 Clockwise Jct Denham Roundabout Lane 3 Closure
Coordinates
51.561783, -0.498131
Latitude span
51.561013 – 51.562607
Longitude span
-0.498371 – -0.497562
Bounding box centre
51.561810, -0.497967
Location descriptions
  • roundabout at M40 J1/A40
  • M40 J1 northbound access
Feed validity status
Planned
Overall feed start
Fri, Sep 26, 2025 10:00 PM
Overall feed end
Sat, Sep 27, 2025 4:00 AM
Feed window length
6 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
Lane Usage
Cl4
Lane Number
4
Lane Status
Closed
Lane Direction
Aligned
Lanes Restricted
1 lane restricted
Operational Lanes
1 operational lane
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
23 m
Gml Srs Name
EPSG::4326
Gml Srs Dimension
2
Raw coordinate list 
51.562422 -0.497724
51.562588 -0.49757
51.562607 -0.497562

Segment 2

2 coordinate pairs
Description
roundabout at M40 J1/A40
Carriageway
Single Carriageway
Lane Usage
Cl4
Lane Number
4
Lane Status
Closed
Lane Direction
Aligned
Lanes Restricted
1 lane restricted
Operational Lanes
3 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
{4D4F3342-201E-4ED0-BFE2-7B95F381A45E}
Linear Element Type
Other
From Distance
0 m
To Distance
19 m
Gml Srs Name
EPSG::4326
Gml Srs Dimension
2
Raw coordinate list 
51.561393 -0.498202
51.561565 -0.498245

Segment 3

2 coordinate pairs
Description
roundabout at M40 J1/A40
Carriageway
Dual Carriageway
Lane Usage
Cl4
Lane Number
4
Lane Status
Closed
Lane Direction
Aligned
Lanes Restricted
1 lane restricted
Operational Lanes
1 operational lane
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 4

2 coordinate pairs
Description
roundabout at M40 J1/A40
Carriageway
Single Carriageway
Lane Usage
Cl4
Lane Number
4
Lane Status
Closed
Lane Direction
Aligned
Lanes Restricted
1 lane restricted
Operational Lanes
3 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
{87054820-C2BE-4FAD-910C-B120A097BD72}
Linear Element Type
Other
From Distance
0 m
To Distance
6 m
Gml Srs Name
EPSG::4326
Gml Srs Dimension
2
Raw coordinate list 
51.561565 -0.498245
51.561623 -0.498263

Segment 5

2 coordinate pairs
Description
roundabout at M40 J1/A40
Carriageway
Single Carriageway
Lane Usage
Cl4
Lane Number
4
Lane Status
Closed
Lane Direction
Aligned
Lanes Restricted
1 lane restricted
Operational Lanes
3 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
{68B846F4-DA2E-4F82-AC98-AAB82A0650AD}
Linear Element Type
Other
From Distance
0 m
To Distance
14 m
Gml Srs Name
EPSG::4326
Gml Srs Dimension
2
Raw coordinate list 
51.561393 -0.498202
51.561267 -0.498167

Segment 6

6 coordinate pairs
Description
roundabout at M40 J1/A40
Carriageway
Dual Carriageway
Lane Usage
Cl4
Lane Number
4
Lane Status
Closed
Lane Direction
Aligned
Lanes Restricted
1 lane restricted
Operational Lanes
1 operational lane
Direction On Section
Clockwise
Direction Relative
Aligned
Height Grade
Start1 End1
Linear Element Road
A40
Linear Element Model
The Network Model
Linear Element Id
{F23E1600-F78D-4BB5-BDC1-CAA016398D0C}
Linear Element Type
Other
From Distance
0 m
To Distance
30 m
Gml Srs Name
EPSG::4326
Gml Srs Dimension
2
Raw coordinate list 
51.561623 -0.498263
51.561651 -0.498349
51.561702 -0.498371
51.561758 -0.498369
51.561801 -0.498367
51.561863 -0.498336

Segment 7

2 coordinate pairs
Description
roundabout at M40 J1/A40
Carriageway
Single Carriageway
Lane Usage
Cl4
Lane Number
4
Lane Status
Closed
Lane Direction
Aligned
Lanes Restricted
1 lane restricted
Operational Lanes
3 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
{DAB73540-16D7-4B15-A678-3562ADE02736}
Linear Element Type
Other
From Distance
0 m
To Distance
19 m
Gml Srs Name
EPSG::4326
Gml Srs Dimension
2
Raw coordinate list 
51.561092 -0.498168
51.561267 -0.498167

Segment 8

4 coordinate pairs
Description
roundabout at M40 J1/A40
Carriageway
Dual Carriageway
Lane Usage
Cl4
Lane Number
4
Lane Status
Closed
Lane Direction
Aligned
Lanes Restricted
1 lane restricted
Operational Lanes
1 operational lane
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
0 m
To Distance
22 m
Gml Srs Name
EPSG::4326
Gml Srs Dimension
2
Raw coordinate list 
51.561863 -0.498336
51.561928 -0.498303
51.561953 -0.49829
51.562051 -0.498215

Segment 9

3 coordinate pairs
Description
M40 J1 northbound access
Carriageway
Dual Carriageway
Lane Usage
Cl4
Lane Number
4
Lane Status
Closed
Lane Direction
Aligned
Lanes Restricted
1 lane restricted
Operational Lanes
1 operational lane
Direction On Section
North Bound
Direction Relative
Aligned
Height Grade
Start1 End1
Linear Element Road
A40
Linear Element Model
The Network Model
Linear Element Id
{805BE05B-25DD-4B51-91E2-515882581AA7}
Linear Element Type
A Carriageway Entry Slip
From Distance
20 m
To Distance
29 m
Gml Srs Name
EPSG::4326
Gml Srs Dimension
2
Raw coordinate list 
51.561013 -0.498119
51.56102 -0.498128
51.561092 -0.498168

Segment 10

4 coordinate pairs
Description
roundabout at M40 J1/A40
Carriageway
Single Carriageway
Lane Usage
Cl4
Lane Number
4
Lane Status
Closed
Lane Direction
Aligned
Lanes Restricted
1 lane restricted
Operational Lanes
3 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
Geometry type
MultiLineString
Geometry points
30
First coordinate pair
-0.497724, 51.562422
Road section segments
1
Road section points
30
View geometry JSON 
{
    "type": "MultiLineString",
    "coordinates": [
        [
            [
                -0.497724,
                51.562422
            ],
            [
                -0.49757,
                51.562588
            ],
            [
                -0.497562,
                51.562607
            ],
            [
                -0.498202,
                51.561393
            ],
            [
                -0.498245,
                51.561565
            ],
            [
                -0.498215,
                51.562051
            ],
            [
                -0.498097,
                51.562121
            ],
            [
                -0.498245,
                51.561565
            ],
            [
                -0.498263,
                51.561623
            ],
            [
                -0.498202,
                51.561393
            ],
            [
                -0.498167,
                51.561267
            ],
            [
                -0.498263,
                51.561623
            ],
            [
                -0.498349,
                51.561651
            ],
            [
                -0.498371,
                51.561702
            ],
            [
                -0.498369,
                51.561758
            ],
            [
                -0.498367,
                51.561801
            ],
            [
                -0.498336,
                51.561863
            ],
            [
                -0.498168,
                51.561092
            ],
            [
                -0.498167,
                51.561267
            ],
            [
                -0.498336,
                51.561863
            ],
            [
                -0.498303,
                51.561928
            ],
            [
                -0.49829,
                51.561953
            ],
            [
                -0.498215,
                51.562051
            ],
            [
                -0.498119,
                51.561013
            ],
            [
                -0.498128,
                51.56102
            ],
            [
                -0.498168,
                51.561092
            ],
            [
                -0.498097,
                51.562121
            ],
            [
                -0.49786,
                51.562325
            ],
            [
                -0.49781,
                51.562361
            ],
            [
                -0.497724,
                51.562422
            ]
        ]
    ]
}
View road section coordinates 
[
    [
        [
            -0.497724,
            51.562422
        ],
        [
            -0.49757,
            51.562588
        ],
        [
            -0.497562,
            51.562607
        ],
        [
            -0.498202,
            51.561393
        ],
        [
            -0.498245,
            51.561565
        ],
        [
            -0.498215,
            51.562051
        ],
        [
            -0.498097,
            51.562121
        ],
        [
            -0.498245,
            51.561565
        ],
        [
            -0.498263,
            51.561623
        ],
        [
            -0.498202,
            51.561393
        ],
        [
            -0.498167,
            51.561267
        ],
        [
            -0.498263,
            51.561623
        ],
        [
            -0.498349,
            51.561651
        ],
        [
            -0.498371,
            51.561702
        ],
        [
            -0.498369,
            51.561758
        ],
        [
            -0.498367,
            51.561801
        ],
        [
            -0.498336,
            51.561863
        ],
        [
            -0.498168,
            51.561092
        ],
        [
            -0.498167,
            51.561267
        ],
        [
            -0.498336,
            51.561863
        ],
        [
            -0.498303,
            51.561928
        ],
        [
            -0.49829,
            51.561953
        ],
        [
            -0.498215,
            51.562051
        ],
        [
            -0.498119,
            51.561013
        ],
        [
            -0.498128,
            51.56102
        ],
        [
            -0.498168,
            51.561092
        ],
        [
            -0.498097,
            51.562121
        ],
        [
            -0.49786,
            51.562325
        ],
        [
            -0.49781,
            51.562361
        ],
        [
            -0.497724,
            51.562422
        ]
    ]
]
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
Fri, Sep 26, 2025 10:15 AM
Record versioned
Fri, Sep 26, 2025 8:00 PM
Coordinate source
Geometry

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