Inadequate drainage leading to water accumulation on carriageway
National Highways received 2 coroners' reports about this hazard between 7 Dec 2022 and 15 Jul 2026.
They came from 2 different coroners in 2 coroner areas. A similar concern was raised again 1 time after the first warning.
A published response was found for 1 of the 1 earlier reports, stating 4 specific actions.
The story, report by report
Spacing grows with the time between reports.
“The crash location is at the bottom of an incline on the M20 motorway which normally would not cause an issue, however the road also has a camber which causes water to run across the carriageway rather than draining into either the central reservation of the drain on the hard shoulder.”
Original on judiciary.uk ↗ National Highways responded, stating 4 specific actions.Response (PDF) ↗Response (PDF) ↗
“South East Regional Operations Centre (SEROC) set variable message signs to display”
Stated timescale: 08 February 2023
“170 metres of combined kerb drainage jetted, 200 metres x 2 Acco drains jetted and a full CCTV drainage survey carried out”
Stated timescale: 08 February 2023
2 more stated actions in the Promises tab.
- 3 years 7 months laterClosely relatedConfidence 0.90 · higha different coroner
“Despite this fatal collision having occurred in December 2025, the topographic and drainage surveys are not yet available and no works other than "minor works for overburden removal" have taken place”
Original on judiciary.uk ↗ National Highways responded.Response (PDF) ↗Response (PDF) ↗
- All reports to National Highways
Each row is one judged link between an earlier and a later report. Open a row to read both quotes, found word for word in the originals.
2022 → 2026Cody Stock3 years 7 months after Josie Archer-Smith · different coronerClosely relatedConfidence 0.90 · high
Closely relatedConfidence 0.90 · highBoth reports highlight inadequate drainage leading to water accumulation on the carriageway that increases the risk of hydroplaning/aquaplaning collisions.
Josie Archer-Smith · 7 Dec 2022
“The crash location is at the bottom of an incline on the M20 motorway which normally would not cause an issue, however the road also has a camber which causes water to run across the carriageway rather than draining into either the central reservation of the drain on the hard shoulder.”
Original on judiciary.uk ↗ Cody Stock · 15 Jul 2026
“Despite this fatal collision having occurred in December 2025, the topographic and drainage surveys are not yet available and no works other than "minor works for overburden removal" have taken place”
Original on judiciary.uk ↗ Stated action in the response to the earlier report
“170 metres of combined kerb drainage jetted, 200 metres x 2 Acco drains jetted and a full CCTV drainage survey carried out”
Stated action · timescale: 08 February 2023
“South East Regional Operations Centre (SEROC) set variable message signs to display”
Stated action · timescale: 08 February 2023
“170 metres of combined kerb drainage jetted, 200 metres x 2 Acco drains jetted and a full CCTV drainage survey carried out”
Stated action · timescale: 08 February 2023
“200 metres of combined kerb drainage jetted and cleaned; ▪ 150 metres of centre reserve drainage channel cleaned;”
Stated action · timescale: June-July 2023
“M20 Medway and Allington Deck Refurbishment scheme is due to be delivered between June and July 2023”
No specific action could be extracted with a verified quote.
No specific action could be extracted with a verified quote.
No specific action could be extracted with a verified quote.
- Each report's concerns were extracted by Nemotron 3 Nano on Nebius Token Factory, each with a quote copied from the report.
- Concerns from reports to National Highways at least six months apart were compared by meaning (Qwen3 embeddings) and wording (TF-IDF).
- The closest pairs were judged by Nemotron 3 Super with reasoning on. Only identical or closely related, with confidence of at least 0.70, are shown.
- Every quote was checked by code as an exact substring of the original text. Names of staff and family are redacted, and the deceased are named by report title only.
| Link | Meaning | Wording | Judge | Coroner |
|---|---|---|---|---|
| 2022 → 2026 | 0.76 | 0.28 | Closely related · 0.90 | different |
Judge model: nvidia/nemotron-3-super-120b-a12b. How Nemotron did the work · Full methodology.
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This shows that a similar concern was raised again after an earlier report. It does not say why, and it is not a finding about any organisation or person. To report an error, see the corrections route.