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CrashStats

HP1 road accidents: crash map and statistics

Police recorded 4,136 road traffic collisions in the HP1 postcode district, Dacorum, from 1979 to 2025, and 5,490 people were killed or injured in them. Of those collisions, 49 were fatal and 787 were serious.

In 2025 police recorded 30 collisions, up 3% on 2024 (29).

Collisions since 1979
4,136
844th highest of 2,813 postcode districts
Casualties
5,490
1.33 per collision
Fatal collisions
49
56 people killed
Serious collisions
787
912 seriously injured
Collisions in 2025
30
Up 3% on 2024
Casualties in 2025
39
Up 15% on 2024

Road collision statistics for HP1

Collisions by severity, 1979 to 2025

  • Fatal491.2%
  • Serious78719%
  • Slight3,30080%

What the data shows

  • HP1 had 371 collisions from 2016 to 2025, 39% fewer than the 605 from 2006 to 2015.
  • 20% of collisions in HP1 were fatal or serious, against 20% across Great Britain.
  • 716 children under 16 were killed or injured in HP1, 13% of the casualties whose age was recorded.
  • The road surface was wet, icy, snowy or flooded in 40% of collisions in HP1.

Where HP1 ranks among 2,813 postcode districts

Most collisions
844th
Most casualties
838th
Most fatal collisions
1,220th
Most serious collisions
762nd

Collisions by day of the week

  • Monday602 (15%)
  • Tuesday551 (13%)
  • Wednesday640 (15%)
  • Thursday644 (16%)
  • Friday588 (14%)
  • Saturday665 (16%)
  • Sunday446 (11%)

Light conditions

  • Daylight2,938 (71%)
  • Dark, street lights lit931 (23%)
  • Dark, no street lighting208 (5%)
  • Dark, lighting unknown40 (1%)
  • Dark, street lights unlit19 (0.5%)

Type of road

  • Single carriageway3,309 (80%)
  • Dual carriageway381 (9.2%)
  • Roundabout373 (9%)
  • One way street or slip road61 (1.5%)
  • Not recorded12 (0.3%)

Speed limit at the scene

  • 20 mph12 (0.3%)
  • 30 mph3,070 (74%)
  • 40 mph118 (2.9%)
  • 50 mph148 (3.6%)
  • 60 mph589 (14%)
  • 70 mph199 (4.8%)

Weather at the time

  • Fine, no high winds3,184 (77%)
  • Raining, no high winds674 (16%)
  • Raining with high winds52 (1.3%)
  • Fine with high winds50 (1.2%)
  • Fog or mist32 (0.8%)
  • Snowing, no high winds23 (0.6%)
  • Snowing with high winds3 (0.1%)
  • Other77 (1.9%)
  • Not recorded41 (1%)

Who was hurt

  • Car occupant3,232 (59%)
  • Pedestrian894 (16%)
  • Motorcyclist771 (14%)
  • Cyclist316 (5.8%)
  • Van occupant114 (2.1%)
  • Bus or coach occupant67 (1.2%)
  • Goods vehicle occupant (over 3.5 tonnes)39 (0.7%)
  • Taxi or private hire car occupant39 (0.7%)
  • Minibus occupant6 (0.1%)
  • Other vehicle occupant5 (0.1%)
  • Other5 (0.1%)
  • Not recorded2 (under 0.1%)

Source: Department for Transport, STATS19 road safety data

HP1 road accidents by year

Collisions and casualties in HP1, 1979 to 2025

Collisions in HP1 peaked at 153 in 1990; 2025 had 30.

  • Collisions
  • Collisions in 2025: 30
  • Casualties

Source: Department for Transport, STATS19 road safety data

View as a table
YearCollisionsCasualties
20253039
20242934
20233441
20223851
20213746
20203033
20194559
20183539
20174457
20164964
20154563
20144059
20134864
20124758
20116885
20105785
20097797
200882101
20076696
200675111
200580109
200491134
200374100
200282107
2001105148
2000120173
199997133
1998115167
1997111170
1996114168
1995106122
1994119152
1993108145
1992115155
1991118150
1990153192
1989138195
1988115140
1987140190
1986143173
1985132175
1984127160
1983142189
1982126172
1981126158
1980134170
1979129161

Map of recent crashes in HP1

Map of the 24 most recent crashes in HP1

Use the arrow keys to move the map and the plus and minus keys to zoom.

  • 24 crashes
  • Fatal
  • Serious
  • Slight

Recent road crashes in HP1

The 24 most recent collisions in HP1 happened between 21 April and 27 December 2025.

Severity

Crashes by road in HP1

The A4146 has the most collisions in HP1, 945 of 4,136 (23%), followed by the A41 (364).

Collisions in HP1 on each road, 1979 to 2025
RankRoadCollisionsCasualtiesFatalSerious
1stA41469451,37124203
2ndA41364535786
3rdA414135174121
4thA4251109159216
5thA414787110111
6thB4878196214
7thB440223318
8thB45057800

Council areas covering HP1

Collisions in HP1 were recorded in 3 council areas. Dacorum has 4,119 of 4,136 (99.6%).

Collisions in HP1 by council area, 1979 to 2025
RankCouncil areaCollisionsCasualtiesFatalSerious
1stDacorum4,1195,46249783
2ndCentral Bedfordshire81803
3rdNorth Hertfordshire5500

Town in HP1

Of the 4,136 collisions in HP1, 2,423 (59%) were in Hemel Hempstead.