M4 eastbound Jct 21 to 20 - lane closures

Active

M4 eastbound Jct 21 to 20 - lane closures

Start time
Mon, Aug 17, 2026 7:44 PM
Expected end
Tue, Aug 18, 2026 5:00 AM
Duration
9 hours 16 minutes
Road
M4 – M4 Eastbound Between J21 And J20
Category
Road Maintenance
Direction
Eastbound
Carriageway
Dual Carriageway
Lanes affected
1 of 3 lanes affected, 1 of 2 lanes affected
Reason
Maintenance Work
Live incident
Active roadworks
Planned
Cleared
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First published
Mon, Aug 17, 2026 7:44 PM
Last updated
Tue, Aug 18, 2026 12:22 AM
Cleared
Tue, Aug 18, 2026 5:00 AM
  • Latest update: M4 eastbound Jct 21 to 20 - lane closures
Coordinates
51.558018, -2.558016
Latitude span
51.553548 – 51.563152
Longitude span
-2.564788 – -2.553043
Bounding box centre
51.558350, -2.558916
Location descriptions
  • M4 eastbound between J21 and J20
  • link road from M4 J20 eastbound to M5 J15 northbound
  • link road from M5 J15 to M5 J20 westbound
  • M4 eastbound within J20
Feed validity status
Active
Overall feed start
Mon, Aug 17, 2026 7:44 PM
Overall feed end
Tue, Aug 18, 2026 5:00 AM
Feed window length
9 hours 16 minutes
Probability code (raw)
certain
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

12 coordinate pairs
Description
M4 eastbound between J21 and J20
Carriageway
Dual Carriageway
Lanes Restricted
1 lane restricted
Operational Lanes
3 operational lanes
Direction On Section
East Bound
Direction Relative
Aligned
Height Grade
Start2 End1
Linear Element Road
M4
Linear Element Model
The Network Model
Linear Element Id
{851BB8E6-6940-4369-BCF5-A96FE8932F11}
Linear Element Type
B Carriageway
From Distance
584 m
To Distance
1,098 m
Gml Srs Name
EPSG::4326
Gml Srs Dimension
2
Raw coordinate list
51.563152 -2.564788
51.563039 -2.564578
51.562736 -2.564011
51.562645 -2.56385
51.562522 -2.563576
51.561416 -2.561701
51.561086 -2.561178
51.560881 -2.560872
51.560732 -2.560668
51.56038 -2.560188
51.560139 -2.559868
51.559898 -2.559545

Segment 2

2 coordinate pairs
Description
link road from M4 J20 eastbound to M5 J15 northbound
Lanes Restricted
1 lane restricted
Operational Lanes
2 operational lanes
Direction On Section
North Bound
Direction Relative
Aligned
Height Grade
Start1 End1
Linear Element Road
M5
Linear Element Model
The Network Model
Linear Element Id
{0B7B371B-00B1-4C02-ACC7-CE21C8F7A7C6}
Linear Element Type
B Carriageway Entry Slip
From Distance
0 m
To Distance
54 m
Gml Srs Name
EPSG::4326
Gml Srs Dimension
2
Raw coordinate list
51.553882 -2.553621
51.553548 -2.553043

Segment 3

12 coordinate pairs
Description
link road from M5 J15 to M5 J20 westbound
Lanes Restricted
1 lane restricted
Operational Lanes
2 operational lanes
Direction On Section
East Bound
Direction Relative
Aligned
Height Grade
Start1 End1
Linear Element Road
M4
Linear Element Model
The Network Model
Linear Element Id
{ABB6A540-40C4-4072-BF82-7D58F2B5555B}
Linear Element Type
B Carriageway Exit Slip
From Distance
98 m
To Distance
462 m
Gml Srs Name
EPSG::4326
Gml Srs Dimension
2
Raw coordinate list
51.556672 -2.556297
51.556668 -2.556294
51.556579 -2.556214
51.555494 -2.555356
51.554866 -2.554858
51.554539 -2.554532
51.554531 -2.554524
51.554464 -2.55444
51.554205 -2.554112
51.554116 -2.553995
51.554071 -2.553923
51.553882 -2.553621

Segment 4

2 coordinate pairs
Description
M4 eastbound within J20
Carriageway
Dual Carriageway
Lanes Restricted
1 lane restricted
Operational Lanes
2 operational lanes
Direction On Section
East Bound
Direction Relative
Aligned
Height Grade
Start1 End1
Linear Element Road
M4
Linear Element Model
The Network Model
Linear Element Id
{28ED533E-2B58-4717-A7A3-2B792A8EAEAA}
Linear Element Type
B Carriageway
From Distance
0 m
To Distance
98 m
Gml Srs Name
EPSG::4326
Gml Srs Dimension
2
Raw coordinate list
51.557446 -2.556984
51.556648 -2.556376

Segment 5

6 coordinate pairs
Description
M4 eastbound between J21 and J20
Carriageway
Dual Carriageway
Lanes Restricted
1 lane restricted
Operational Lanes
3 operational lanes
Direction On Section
East Bound
Direction Relative
Aligned
Height Grade
Start1 End1
Linear Element Road
M4
Linear Element Model
The Network Model
Linear Element Id
{BBCF13CD-84AD-4542-B91E-D5E3F80455EE}
Linear Element Type
B Carriageway
From Distance
0 m
To Distance
325 m
Gml Srs Name
EPSG::4326
Gml Srs Dimension
2
Raw coordinate list
51.559898 -2.559545
51.559388 -2.55895
51.558879 -2.558366
51.558404 -2.55787
51.558351 -2.557826
51.557446 -2.556984
Geometry type
MultiLineString
Geometry points
34
First coordinate pair
-2.564788, 51.563152
Road section segments
1
Road section points
34
View geometry JSON
{
    "type": "MultiLineString",
    "coordinates": [
        [
            [
                -2.564788,
                51.563152
            ],
            [
                -2.564578,
                51.563039
            ],
            [
                -2.564011,
                51.562736
            ],
            [
                -2.56385,
                51.562645
            ],
            [
                -2.563576,
                51.562522
            ],
            [
                -2.561701,
                51.561416
            ],
            [
                -2.561178,
                51.561086
            ],
            [
                -2.560872,
                51.560881
            ],
            [
                -2.560668,
                51.560732
            ],
            [
                -2.560188,
                51.56038
            ],
            [
                -2.559868,
                51.560139
            ],
            [
                -2.559545,
                51.559898
            ],
            [
                -2.553621,
                51.553882
            ],
            [
                -2.553043,
                51.553548
            ],
            [
                -2.556297,
                51.556672
            ],
            [
                -2.556294,
                51.556668
            ],
            [
                -2.556214,
                51.556579
            ],
            [
                -2.555356,
                51.555494
            ],
            [
                -2.554858,
                51.554866
            ],
            [
                -2.554532,
                51.554539
            ],
            [
                -2.554524,
                51.554531
            ],
            [
                -2.55444,
                51.554464
            ],
            [
                -2.554112,
                51.554205
            ],
            [
                -2.553995,
                51.554116
            ],
            [
                -2.553923,
                51.554071
            ],
            [
                -2.553621,
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            ],
            [
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            ],
            [
                -2.556376,
                51.556648
            ],
            [
                -2.559545,
                51.559898
            ],
            [
                -2.55895,
                51.559388
            ],
            [
                -2.558366,
                51.558879
            ],
            [
                -2.55787,
                51.558404
            ],
            [
                -2.557826,
                51.558351
            ],
            [
                -2.556984,
                51.557446
            ]
        ]
    ]
}
View road section coordinates
[
    [
        [
            -2.564788,
            51.563152
        ],
        [
            -2.564578,
            51.563039
        ],
        [
            -2.564011,
            51.562736
        ],
        [
            -2.56385,
            51.562645
        ],
        [
            -2.563576,
            51.562522
        ],
        [
            -2.561701,
            51.561416
        ],
        [
            -2.561178,
            51.561086
        ],
        [
            -2.560872,
            51.560881
        ],
        [
            -2.560668,
            51.560732
        ],
        [
            -2.560188,
            51.56038
        ],
        [
            -2.559868,
            51.560139
        ],
        [
            -2.559545,
            51.559898
        ],
        [
            -2.553621,
            51.553882
        ],
        [
            -2.553043,
            51.553548
        ],
        [
            -2.556297,
            51.556672
        ],
        [
            -2.556294,
            51.556668
        ],
        [
            -2.556214,
            51.556579
        ],
        [
            -2.555356,
            51.555494
        ],
        [
            -2.554858,
            51.554866
        ],
        [
            -2.554532,
            51.554539
        ],
        [
            -2.554524,
            51.554531
        ],
        [
            -2.55444,
            51.554464
        ],
        [
            -2.554112,
            51.554205
        ],
        [
            -2.553995,
            51.554116
        ],
        [
            -2.553923,
            51.554071
        ],
        [
            -2.553621,
            51.553882
        ],
        [
            -2.556984,
            51.557446
        ],
        [
            -2.556376,
            51.556648
        ],
        [
            -2.559545,
            51.559898
        ],
        [
            -2.55895,
            51.559388
        ],
        [
            -2.558366,
            51.558879
        ],
        [
            -2.55787,
            51.558404
        ],
        [
            -2.557826,
            51.558351
        ],
        [
            -2.556984,
            51.557446
        ]
    ]
]
Cause type
Road Maintenance
Detailed cause
Maintenance Work
Compliance
Mandatory
Probability
Certain
Validity status
Active
Road management
Other
Feed provider
National Highways
Data source
Roadworks
Feed version
1
Record created
Mon, Aug 17, 2026 7:44 PM
Record versioned
Tue, Aug 18, 2026 12:22 AM
Coordinate source
Geometry

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