River level River Colne at London Colney

Latest recorded level 1.34m at 6:00pm Wednesday 20 January 2021.

Levels: last 5 days and next 36 hours

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Measured level
Forecast level
Property flooding possible
Low lying land may flood
Highest recorded level. Hide
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Observed data

DateTime	Value	Error
2021-01-20T18:00Z	1.335	false
2021-01-20T17:45Z	1.333	false
2021-01-20T17:30Z	1.333	false
2021-01-20T17:15Z	1.333	false
2021-01-20T17:00Z	1.333	false
2021-01-20T16:45Z	1.331	false
2021-01-20T16:30Z	1.332	false
2021-01-20T16:15Z	1.33	false
2021-01-20T16:00Z	1.331	false
2021-01-20T15:45Z	1.329	false
2021-01-20T15:30Z	1.329	false
2021-01-20T15:15Z	1.33	false
2021-01-20T15:00Z	1.33	false
2021-01-20T14:45Z	1.33	false
2021-01-20T14:30Z	1.33	false
2021-01-20T14:15Z	1.331	false
2021-01-20T14:00Z	1.33	false
2021-01-20T13:45Z	1.331	false
2021-01-20T13:30Z	1.33	false
2021-01-20T13:15Z	1.332	false
2021-01-20T13:00Z	1.333	false
2021-01-20T12:45Z	1.334	false
2021-01-20T12:30Z	1.335	false
2021-01-20T12:15Z	1.335	false
2021-01-20T12:00Z	1.335	false
2021-01-20T11:45Z	1.335	false
2021-01-20T11:30Z	1.336	false
2021-01-20T11:15Z	1.336	false
2021-01-20T11:00Z	1.337	false
2021-01-20T10:45Z	1.337	false
2021-01-20T10:30Z	1.338	false
2021-01-20T10:15Z	1.339	false
2021-01-20T10:00Z	1.339	false
2021-01-20T09:45Z	1.338	false
2021-01-20T09:30Z	1.338	false
2021-01-20T09:15Z	1.339	false
2021-01-20T09:00Z	1.339	false
2021-01-20T08:45Z	1.34	false
2021-01-20T08:30Z	1.34	false
2021-01-20T08:15Z	1.342	false
2021-01-20T08:00Z	1.341	false
2021-01-20T07:45Z	1.341	false
2021-01-20T07:30Z	1.342	false
2021-01-20T07:15Z	1.342	false
2021-01-20T07:00Z	1.343	false
2021-01-20T06:45Z	1.343	false
2021-01-20T06:30Z	1.344	false
2021-01-20T06:15Z	1.345	false
2021-01-20T06:00Z	1.345	false
2021-01-20T05:45Z	1.345	false
2021-01-20T05:30Z	1.348	false
2021-01-20T05:15Z	1.347	false
2021-01-20T05:00Z	1.349	false
2021-01-20T04:45Z	1.349	false
2021-01-20T04:30Z	1.349	false
2021-01-20T04:15Z	1.348	false
2021-01-20T04:00Z	1.35	false
2021-01-20T03:45Z	1.351	false
2021-01-20T03:30Z	1.352	false
2021-01-20T03:15Z	1.353	false
2021-01-20T03:00Z	1.355	false
2021-01-20T02:45Z	1.355	false
2021-01-20T02:30Z	1.355	false
2021-01-20T02:15Z	1.356	false
2021-01-20T02:00Z	1.357	false
2021-01-20T01:45Z	1.358	false
2021-01-20T01:30Z	1.359	false
2021-01-20T01:15Z	1.36	false
2021-01-20T01:00Z	1.36	false
2021-01-20T00:45Z	1.363	false
2021-01-20T00:30Z	1.363	false
2021-01-20T00:15Z	1.363	false
2021-01-20T00:00Z	1.365	false
2021-01-19T23:45Z	1.366	false
2021-01-19T23:30Z	1.366	false
2021-01-19T23:15Z	1.369	false
2021-01-19T23:00Z	1.37	false
2021-01-19T22:45Z	1.371	false
2021-01-19T22:30Z	1.371	false
2021-01-19T22:15Z	1.373	false
2021-01-19T22:00Z	1.375	false
2021-01-19T21:45Z	1.375	false
2021-01-19T21:30Z	1.377	false
2021-01-19T21:15Z	1.378	false
2021-01-19T21:00Z	1.38	false
2021-01-19T20:45Z	1.381	false
2021-01-19T20:30Z	1.382	false
2021-01-19T20:15Z	1.383	false
2021-01-19T20:00Z	1.385	false
2021-01-19T19:45Z	1.384	false
2021-01-19T19:30Z	1.386	false
2021-01-19T19:15Z	1.386	false
2021-01-19T19:00Z	1.387	false
2021-01-19T18:45Z	1.389	false
2021-01-19T18:30Z	1.389	false
2021-01-19T18:15Z	1.388	false
2021-01-19T18:00Z	1.391	false
2021-01-19T17:45Z	1.389	false
2021-01-19T17:30Z	1.389	false
2021-01-19T17:15Z	1.389	false
2021-01-19T17:00Z	1.387	false
2021-01-19T16:45Z	1.389	false
2021-01-19T16:30Z	1.387	false
2021-01-19T16:15Z	1.387	false
2021-01-19T16:00Z	1.386	false
2021-01-19T15:45Z	1.384	false
2021-01-19T15:30Z	1.381	false
2021-01-19T15:15Z	1.379	false
2021-01-19T15:00Z	1.377	false
2021-01-19T14:45Z	1.374	false
2021-01-19T14:30Z	1.37	false
2021-01-19T14:15Z	1.368	false
2021-01-19T14:00Z	1.363	false
2021-01-19T13:45Z	1.361	false
2021-01-19T13:30Z	1.359	false
2021-01-19T13:15Z	1.355	false
2021-01-19T13:00Z	1.354	false
2021-01-19T12:45Z	1.352	false
2021-01-19T12:30Z	1.349	false
2021-01-19T12:15Z	1.347	false
2021-01-19T12:00Z	1.345	false
2021-01-19T11:45Z	1.341	false
2021-01-19T11:30Z	1.34	false
2021-01-19T11:15Z	1.338	false
2021-01-19T11:00Z	1.337	false
2021-01-19T10:45Z	1.334	false
2021-01-19T10:30Z	1.334	false
2021-01-19T10:15Z	1.332	false
2021-01-19T10:00Z	1.332	false
2021-01-19T09:45Z	1.331	false
2021-01-19T09:30Z	1.33	false
2021-01-19T09:15Z	1.33	false
2021-01-19T09:00Z	1.33	false
2021-01-19T08:45Z	1.329	false
2021-01-19T08:30Z	1.33	false
2021-01-19T08:15Z	1.33	false
2021-01-19T08:00Z	1.329	false
2021-01-19T07:45Z	1.329	false
2021-01-19T07:30Z	1.329	false
2021-01-19T07:15Z	1.329	false
2021-01-19T07:00Z	1.329	false
2021-01-19T06:45Z	1.33	false
2021-01-19T06:30Z	1.329	false
2021-01-19T06:15Z	1.328	false
2021-01-19T06:00Z	1.329	false
2021-01-19T05:45Z	1.329	false
2021-01-19T05:30Z	1.331	false
2021-01-19T05:15Z	1.331	false
2021-01-19T05:00Z	1.33	false
2021-01-19T04:45Z	1.331	false
2021-01-19T04:30Z	1.332	false
2021-01-19T04:15Z	1.332	false
2021-01-19T04:00Z	1.332	false
2021-01-19T03:45Z	1.333	false
2021-01-19T03:30Z	1.332	false
2021-01-19T03:15Z	1.333	false
2021-01-19T03:00Z	1.334	false
2021-01-19T02:45Z	1.334	false
2021-01-19T02:30Z	1.333	false
2021-01-19T02:15Z	1.333	false
2021-01-19T02:00Z	1.334	false
2021-01-19T01:45Z	1.335	false
2021-01-19T01:30Z	1.336	false
2021-01-19T01:15Z	1.335	false
2021-01-19T01:00Z	1.335	false
2021-01-19T00:45Z	1.336	false
2021-01-19T00:30Z	1.337	false
2021-01-19T00:15Z	1.338	false
2021-01-19T00:00Z	1.339	false
2021-01-18T23:45Z	1.339	false
2021-01-18T23:30Z	1.34	false
2021-01-18T23:15Z	1.34	false
2021-01-18T23:00Z	1.341	false
2021-01-18T22:45Z	1.342	false
2021-01-18T22:30Z	1.342	false
2021-01-18T22:15Z	1.342	false
2021-01-18T22:00Z	1.343	false
2021-01-18T21:45Z	1.344	false
2021-01-18T21:30Z	1.344	false
2021-01-18T21:15Z	1.344	false
2021-01-18T21:00Z	1.344	false
2021-01-18T20:45Z	1.344	false
2021-01-18T20:30Z	1.344	false
2021-01-18T20:15Z	1.345	false
2021-01-18T20:00Z	1.345	false
2021-01-18T19:45Z	1.345	false
2021-01-18T19:30Z	1.345	false
2021-01-18T19:15Z	1.345	false
2021-01-18T19:00Z	1.345	false
2021-01-18T18:45Z	1.346	false
2021-01-18T18:30Z	1.345	false
2021-01-18T18:15Z	1.345	false
2021-01-18T18:00Z	1.346	false
2021-01-18T17:45Z	1.346	false
2021-01-18T17:30Z	1.346	false
2021-01-18T17:15Z	1.347	false
2021-01-18T17:00Z	1.347	false
2021-01-18T16:45Z	1.347	false
2021-01-18T16:30Z	1.347	false
2021-01-18T16:15Z	1.348	false
2021-01-18T16:00Z	1.348	false
2021-01-18T15:45Z	1.348	false
2021-01-18T15:30Z	1.349	false
2021-01-18T15:15Z	1.349	false
2021-01-18T15:00Z	1.349	false
2021-01-18T14:45Z	1.349	false
2021-01-18T14:30Z	1.35	false
2021-01-18T14:15Z	1.35	false
2021-01-18T14:00Z	1.35	false
2021-01-18T13:45Z	1.35	false
2021-01-18T13:30Z	1.351	false
2021-01-18T13:15Z	1.352	false
2021-01-18T13:00Z	1.351	false
2021-01-18T12:45Z	1.352	false
2021-01-18T12:30Z	1.353	false
2021-01-18T12:15Z	1.353	false
2021-01-18T12:00Z	1.355	false
2021-01-18T11:45Z	1.35	false
2021-01-18T11:30Z	1.352	false
2021-01-18T11:15Z	1.351	false
2021-01-18T11:00Z	1.353	false
2021-01-18T10:45Z	1.354	false
2021-01-18T10:30Z	1.355	false
2021-01-18T10:15Z	1.356	false
2021-01-18T10:00Z	1.357	false
2021-01-18T09:45Z	1.357	false
2021-01-18T09:30Z	1.359	false
2021-01-18T09:15Z	1.358	false
2021-01-18T09:00Z	1.36	false
2021-01-18T08:45Z	1.361	false
2021-01-18T08:30Z	1.361	false
2021-01-18T08:15Z	1.363	false
2021-01-18T08:00Z	1.364	false
2021-01-18T07:45Z	1.365	false
2021-01-18T07:30Z	1.366	false
2021-01-18T07:15Z	1.367	false
2021-01-18T07:00Z	1.367	false
2021-01-18T06:45Z	1.366	false
2021-01-18T06:30Z	1.368	false
2021-01-18T06:15Z	1.369	false
2021-01-18T06:00Z	1.369	false
2021-01-18T05:45Z	1.368	false
2021-01-18T05:30Z	1.369	false
2021-01-18T05:15Z	1.369	false
2021-01-18T05:00Z	1.371	false
2021-01-18T04:45Z	1.372	false
2021-01-18T04:30Z	1.372	false
2021-01-18T04:15Z	1.373	false
2021-01-18T04:00Z	1.373	false
2021-01-18T03:45Z	1.375	false
2021-01-18T03:30Z	1.376	false
2021-01-18T03:15Z	1.377	false
2021-01-18T03:00Z	1.378	false
2021-01-18T02:45Z	1.379	false
2021-01-18T02:30Z	1.38	false
2021-01-18T02:15Z	1.381	false
2021-01-18T02:00Z	1.382	false
2021-01-18T01:45Z	1.385	false
2021-01-18T01:30Z	1.384	false
2021-01-18T01:15Z	1.387	false
2021-01-18T01:00Z	1.387	false
2021-01-18T00:45Z	1.389	false
2021-01-18T00:30Z	1.389	false
2021-01-18T00:15Z	1.391	false
2021-01-18T00:00Z	1.393	false
2021-01-17T23:45Z	1.395	false
2021-01-17T23:30Z	1.397	false
2021-01-17T23:15Z	1.397	false
2021-01-17T23:00Z	1.399	false
2021-01-17T22:45Z	1.401	false
2021-01-17T22:30Z	1.402	false
2021-01-17T22:15Z	1.404	false
2021-01-17T22:00Z	1.403	false
2021-01-17T21:45Z	1.403	false
2021-01-17T21:30Z	1.405	false
2021-01-17T21:15Z	1.407	false
2021-01-17T21:00Z	1.409	false
2021-01-17T20:45Z	1.41	false
2021-01-17T20:30Z	1.411	false
2021-01-17T20:15Z	1.412	false
2021-01-17T20:00Z	1.413	false
2021-01-17T19:45Z	1.412	false
2021-01-17T19:30Z	1.415	false
2021-01-17T19:15Z	1.416	false
2021-01-17T19:00Z	1.418	false
2021-01-17T18:45Z	1.419	false
2021-01-17T18:30Z	1.421	false
2021-01-17T18:15Z	1.424	false
2021-01-17T18:00Z	1.426	false
2021-01-17T17:45Z	1.428	false
2021-01-17T17:30Z	1.431	false
2021-01-17T17:15Z	1.433	false
2021-01-17T17:00Z	1.435	false
2021-01-17T16:45Z	1.437	false
2021-01-17T16:30Z	1.439	false
2021-01-17T16:15Z	1.442	false
2021-01-17T16:00Z	1.445	false
2021-01-17T15:45Z	1.447	false
2021-01-17T15:30Z	1.449	false
2021-01-17T15:15Z	1.451	false
2021-01-17T15:00Z	1.452	false
2021-01-17T14:45Z	1.453	false
2021-01-17T14:30Z	1.455	false
2021-01-17T14:15Z	1.458	false
2021-01-17T14:00Z	1.46	false
2021-01-17T13:45Z	1.462	false
2021-01-17T13:30Z	1.464	false
2021-01-17T13:15Z	1.467	false
2021-01-17T13:00Z	1.468	false
2021-01-17T12:45Z	1.47	false
2021-01-17T12:30Z	1.473	false
2021-01-17T12:15Z	1.475	false
2021-01-17T12:00Z	1.478	false
2021-01-17T11:45Z	1.483	false
2021-01-17T11:30Z	1.485	false
2021-01-17T11:15Z	1.487	false
2021-01-17T11:00Z	1.491	false
2021-01-17T10:45Z	1.493	false
2021-01-17T10:30Z	1.495	false
2021-01-17T10:15Z	1.498	false
2021-01-17T10:00Z	1.501	false
2021-01-17T09:45Z	1.504	false
2021-01-17T09:30Z	1.507	false
2021-01-17T09:15Z	1.51	false
2021-01-17T09:00Z	1.511	false
2021-01-17T08:45Z	1.515	false
2021-01-17T08:30Z	1.518	false
2021-01-17T08:15Z	1.523	false
2021-01-17T08:00Z	1.528	false
2021-01-17T07:45Z	1.533	false
2021-01-17T07:30Z	1.539	false
2021-01-17T07:15Z	1.544	false
2021-01-17T07:00Z	1.55	false
2021-01-17T06:45Z	1.556	false
2021-01-17T06:30Z	1.563	false
2021-01-17T06:15Z	1.569	false
2021-01-17T06:00Z	1.577	false
2021-01-17T05:45Z	1.583	false
2021-01-17T05:30Z	1.589	false
2021-01-17T05:15Z	1.596	false
2021-01-17T05:00Z	1.601	false
2021-01-17T04:45Z	1.607	false
2021-01-17T04:30Z	1.614	false
2021-01-17T04:15Z	1.618	false
2021-01-17T04:00Z	1.624	false
2021-01-17T03:45Z	1.629	false
2021-01-17T03:30Z	1.633	false
2021-01-17T03:15Z	1.635	false
2021-01-17T03:00Z	1.639	false
2021-01-17T02:45Z	1.642	false
2021-01-17T02:30Z	1.644	false
2021-01-17T02:15Z	1.645	false
2021-01-17T02:00Z	1.646	false
2021-01-17T01:45Z	1.647	false
2021-01-17T01:30Z	1.647	false
2021-01-17T01:15Z	1.646	false
2021-01-17T01:00Z	1.645	false
2021-01-17T00:45Z	1.644	false
2021-01-17T00:30Z	1.643	false
2021-01-17T00:15Z	1.642	false
2021-01-17T00:00Z	1.64	false
2021-01-16T23:45Z	1.638	false
2021-01-16T23:30Z	1.635	false
2021-01-16T23:15Z	1.632	false
2021-01-16T23:00Z	1.629	false
2021-01-16T22:45Z	1.626	false
2021-01-16T22:30Z	1.623	false
2021-01-16T22:15Z	1.618	false
2021-01-16T22:00Z	1.614	false
2021-01-16T21:45Z	1.61	false
2021-01-16T21:30Z	1.606	false
2021-01-16T21:15Z	1.601	false
2021-01-16T21:00Z	1.597	false
2021-01-16T20:45Z	1.592	false
2021-01-16T20:30Z	1.589	false
2021-01-16T20:15Z	1.584	false
2021-01-16T20:00Z	1.58	false
2021-01-16T19:45Z	1.576	false
2021-01-16T19:30Z	1.572	false
2021-01-16T19:15Z	1.568	false
2021-01-16T19:00Z	1.563	false
2021-01-16T18:45Z	1.559	false
2021-01-16T18:30Z	1.553	false
2021-01-16T18:15Z	1.548	false
2021-01-16T18:00Z	1.541	false
2021-01-16T17:45Z	1.534	false
2021-01-16T17:30Z	1.528	false
2021-01-16T17:15Z	1.523	false
2021-01-16T17:00Z	1.517	false
2021-01-16T16:45Z	1.51	false
2021-01-16T16:30Z	1.502	false
2021-01-16T16:15Z	1.493	false
2021-01-16T16:00Z	1.483	false
2021-01-16T15:45Z	1.473	false
2021-01-16T15:30Z	1.461	false
2021-01-16T15:15Z	1.45	false
2021-01-16T15:00Z	1.44	false
2021-01-16T14:45Z	1.431	false
2021-01-16T14:30Z	1.424	false
2021-01-16T14:15Z	1.419	false
2021-01-16T14:00Z	1.414	false
2021-01-16T13:45Z	1.41	false
2021-01-16T13:30Z	1.406	false
2021-01-16T13:15Z	1.402	false
2021-01-16T13:00Z	1.399	false
2021-01-16T12:45Z	1.397	false
2021-01-16T12:30Z	1.395	false
2021-01-16T12:15Z	1.393	false
2021-01-16T12:00Z	1.392	false
2021-01-16T11:45Z	1.392	false
2021-01-16T11:30Z	1.391	false
2021-01-16T11:15Z	1.391	false
2021-01-16T11:00Z	1.39	false
2021-01-16T10:45Z	1.39	false
2021-01-16T10:30Z	1.39	false
2021-01-16T10:15Z	1.391	false
2021-01-16T10:00Z	1.392	false
2021-01-16T09:45Z	1.393	false
2021-01-16T09:30Z	1.394	false
2021-01-16T09:15Z	1.395	false
2021-01-16T09:00Z	1.394	false
2021-01-16T08:45Z	1.395	false
2021-01-16T08:30Z	1.395	false
2021-01-16T08:15Z	1.393	false
2021-01-16T08:00Z	1.394	false
2021-01-16T07:45Z	1.393	false
2021-01-16T07:30Z	1.394	false
2021-01-16T07:15Z	1.394	false
2021-01-16T07:00Z	1.394	false
2021-01-16T06:45Z	1.396	false
2021-01-16T06:30Z	1.397	false
2021-01-16T06:15Z	1.398	false
2021-01-16T06:00Z	1.399	false
2021-01-16T05:45Z	1.4	false
2021-01-16T05:30Z	1.402	false
2021-01-16T05:15Z	1.405	false
2021-01-16T05:00Z	1.408	false
2021-01-16T04:45Z	1.411	false
2021-01-16T04:30Z	1.412	false
2021-01-16T04:15Z	1.405	false
2021-01-16T04:00Z	1.405	false
2021-01-16T03:45Z	1.407	false
2021-01-16T03:30Z	1.408	false
2021-01-16T03:15Z	1.41	false
2021-01-16T03:00Z	1.413	false
2021-01-16T02:45Z	1.414	false
2021-01-16T02:30Z	1.415	false
2021-01-16T02:15Z	1.416	false
2021-01-16T02:00Z	1.416	false
2021-01-16T01:45Z	1.419	false
2021-01-16T01:30Z	1.421	false
2021-01-16T01:15Z	1.422	false
2021-01-16T01:00Z	1.424	false
2021-01-16T00:45Z	1.427	false
2021-01-16T00:30Z	1.427	false
2021-01-16T00:15Z	1.429	false
2021-01-16T00:00Z	1.429	false
2021-01-15T23:45Z	1.432	false
2021-01-15T23:30Z	1.434	false
2021-01-15T23:15Z	1.436	false
2021-01-15T23:00Z	1.437	false
2021-01-15T22:45Z	1.439	false
2021-01-15T22:30Z	1.442	false

Forecast data

January 20th 2021, 6:00:00 pm	1.335
January 20th 2021, 6:15:00 pm	1.335
January 20th 2021, 6:30:00 pm	1.337
January 20th 2021, 6:45:00 pm	1.337
January 20th 2021, 7:00:00 pm	1.338
January 20th 2021, 7:15:00 pm	1.338
January 20th 2021, 7:30:00 pm	1.339
January 20th 2021, 7:45:00 pm	1.339
January 20th 2021, 8:00:00 pm	1.339
January 20th 2021, 8:15:00 pm	1.340
January 20th 2021, 8:30:00 pm	1.340
January 20th 2021, 8:45:00 pm	1.340
January 20th 2021, 9:00:00 pm	1.340
January 20th 2021, 9:15:00 pm	1.340
January 20th 2021, 9:30:00 pm	1.340
January 20th 2021, 9:45:00 pm	1.340
January 20th 2021, 10:00:00 pm	1.340
January 20th 2021, 10:15:00 pm	1.340
January 20th 2021, 10:30:00 pm	1.341
January 20th 2021, 10:45:00 pm	1.341
January 20th 2021, 11:00:00 pm	1.341
January 20th 2021, 11:15:00 pm	1.341
January 20th 2021, 11:30:00 pm	1.341
January 20th 2021, 11:45:00 pm	1.342
January 21st 2021, 12:00:00 am	1.343
January 21st 2021, 12:15:00 am	1.344
January 21st 2021, 12:30:00 am	1.344
January 21st 2021, 12:45:00 am	1.345
January 21st 2021, 1:00:00 am	1.346
January 21st 2021, 1:15:00 am	1.347
January 21st 2021, 1:30:00 am	1.347
January 21st 2021, 1:45:00 am	1.348
January 21st 2021, 2:00:00 am	1.350
January 21st 2021, 2:15:00 am	1.351
January 21st 2021, 2:30:00 am	1.352
January 21st 2021, 2:45:00 am	1.353
January 21st 2021, 3:00:00 am	1.354
January 21st 2021, 3:15:00 am	1.356
January 21st 2021, 3:30:00 am	1.356
January 21st 2021, 3:45:00 am	1.357
January 21st 2021, 4:00:00 am	1.357
January 21st 2021, 4:15:00 am	1.358
January 21st 2021, 4:30:00 am	1.358
January 21st 2021, 4:45:00 am	1.358
January 21st 2021, 5:00:00 am	1.359
January 21st 2021, 5:15:00 am	1.358
January 21st 2021, 5:30:00 am	1.358
January 21st 2021, 5:45:00 am	1.358
January 21st 2021, 6:00:00 am	1.358
January 21st 2021, 6:15:00 am	1.357
January 21st 2021, 6:30:00 am	1.356
January 21st 2021, 6:45:00 am	1.356
January 21st 2021, 7:00:00 am	1.355
January 21st 2021, 7:15:00 am	1.354
January 21st 2021, 7:30:00 am	1.354
January 21st 2021, 7:45:00 am	1.353
January 21st 2021, 8:00:00 am	1.352
January 21st 2021, 8:15:00 am	1.351
January 21st 2021, 8:30:00 am	1.351
January 21st 2021, 8:45:00 am	1.350
January 21st 2021, 9:00:00 am	1.348
January 21st 2021, 9:15:00 am	1.348
January 21st 2021, 9:30:00 am	1.347
January 21st 2021, 9:45:00 am	1.346
January 21st 2021, 10:00:00 am	1.346
January 21st 2021, 10:15:00 am	1.348
January 21st 2021, 10:30:00 am	1.352
January 21st 2021, 10:45:00 am	1.358
January 21st 2021, 11:00:00 am	1.368
January 21st 2021, 11:15:00 am	1.380
January 21st 2021, 11:30:00 am	1.394
January 21st 2021, 11:45:00 am	1.407
January 21st 2021, 12:00:00 pm	1.419
January 21st 2021, 12:15:00 pm	1.430
January 21st 2021, 12:30:00 pm	1.438
January 21st 2021, 12:45:00 pm	1.445
January 21st 2021, 1:00:00 pm	1.451
January 21st 2021, 1:15:00 pm	1.456
January 21st 2021, 1:30:00 pm	1.458
January 21st 2021, 1:45:00 pm	1.461
January 21st 2021, 2:00:00 pm	1.462
January 21st 2021, 2:15:00 pm	1.463
January 21st 2021, 2:30:00 pm	1.461
January 21st 2021, 2:45:00 pm	1.460
January 21st 2021, 3:00:00 pm	1.458
January 21st 2021, 3:15:00 pm	1.455
January 21st 2021, 3:30:00 pm	1.451
January 21st 2021, 3:45:00 pm	1.448
January 21st 2021, 4:00:00 pm	1.444
January 21st 2021, 4:15:00 pm	1.440
January 21st 2021, 4:30:00 pm	1.435
January 21st 2021, 4:45:00 pm	1.430
January 21st 2021, 5:00:00 pm	1.426
January 21st 2021, 5:15:00 pm	1.421
January 21st 2021, 5:30:00 pm	1.417
January 21st 2021, 5:45:00 pm	1.413
January 21st 2021, 6:00:00 pm	1.409
January 21st 2021, 6:15:00 pm	1.404
January 21st 2021, 6:30:00 pm	1.400
January 21st 2021, 6:45:00 pm	1.396
January 21st 2021, 7:00:00 pm	1.392
January 21st 2021, 7:15:00 pm	1.387
January 21st 2021, 7:30:00 pm	1.383
January 21st 2021, 7:45:00 pm	1.379
January 21st 2021, 8:00:00 pm	1.375
January 21st 2021, 8:15:00 pm	1.370
January 21st 2021, 8:30:00 pm	1.366
January 21st 2021, 8:45:00 pm	1.362
January 21st 2021, 9:00:00 pm	1.358
January 21st 2021, 9:15:00 pm	1.354
January 21st 2021, 9:30:00 pm	1.350
January 21st 2021, 9:45:00 pm	1.347
January 21st 2021, 10:00:00 pm	1.343
January 21st 2021, 10:15:00 pm	1.340
January 21st 2021, 10:30:00 pm	1.335
January 21st 2021, 10:45:00 pm	1.332
January 21st 2021, 11:00:00 pm	1.330
January 21st 2021, 11:15:00 pm	1.328
January 21st 2021, 11:30:00 pm	1.324
January 21st 2021, 11:45:00 pm	1.322
January 22nd 2021, 12:00:00 am	1.321
January 22nd 2021, 12:15:00 am	1.319
January 22nd 2021, 12:30:00 am	1.316
January 22nd 2021, 12:45:00 am	1.315
January 22nd 2021, 1:00:00 am	1.314
January 22nd 2021, 1:15:00 am	1.313
January 22nd 2021, 1:30:00 am	1.311
January 22nd 2021, 1:45:00 am	1.310
January 22nd 2021, 2:00:00 am	1.309
January 22nd 2021, 2:15:00 am	1.309
January 22nd 2021, 2:30:00 am	1.307
January 22nd 2021, 2:45:00 am	1.307
January 22nd 2021, 3:00:00 am	1.307
January 22nd 2021, 3:15:00 am	1.306
January 22nd 2021, 3:30:00 am	1.306
January 22nd 2021, 3:45:00 am	1.305
January 22nd 2021, 4:00:00 am	1.305
January 22nd 2021, 4:15:00 am	1.306
January 22nd 2021, 4:30:00 am	1.306
January 22nd 2021, 4:45:00 am	1.305
January 22nd 2021, 5:00:00 am	1.305
January 22nd 2021, 5:15:00 am	1.305
January 22nd 2021, 5:30:00 am	1.305
January 22nd 2021, 5:45:00 am	1.305
January 22nd 2021, 6:00:00 am	1.305

Forecasts contain uncertainty and can change frequently. For the latest information, always check for up to date flood warnings and alerts in your area.

Key information

How are river levels measured?

The Environment agency uses a network of monitoring stations across the country. Each one has its own datum - a height in metres fixed relative to mean sea level. This height is expressed as metres above ordnance datum (mAOD). The river levels we provide for each monitoring station are all relative to its site datum.

If we didn't do this, we'd show some very high measurements, which could cause confusion. By using a local site datum, the river levels are easier to understand, especially by users familiar with the data from a particular monitoring station.

A river's height above ordnance datum can be seen by adding the site datum to the river level.

How often are river levels measured?

How might river levels affect flood risk?

Typical range

This is the usual range of river levels at this station, based on historical data.

Above typical

This means that flooding is possible because river levels at this station are currently higher than usual.
Many factors can influence the possibility of flooding - river levels are only one indicator. Always check if there's a flood warning in place at a particular location.

Below typical

This means that river levels at this station are currently lower than usual.
Drought or water management measures may be in place. Please check for the latest information on water resources and restrictions in your area.

How are forecasts produced?

The forecasts shown here are computer models based on technical data, local conditions and Met Office rainfall predictions and may contain uncertainty. Because they’re linked to the weather, forecasts can change quickly. We update them more frequently if the risk of flooding increases.

When we issue flood warnings and alerts we assess many factors including these forecasts, local conditions, tides and the weather forecast.

Flood warnings and alerts can still be issued even if water levels at a measuring station are forecast to remain within its typical range. For the latest information, always check for up to date flood warnings and alerts.

What effect could these levels have on nearby areas?

Typical range at this location

0.94m to 1.85m.

Above 1.85m flooding of low-lying land may occur in these areas

Upper River Colne and Radlett Brook

Above 2.30m some property flooding may occur in these areas

River Colne at London Colney

Highest forecast level at this location

The highest level forecast in the next 36 hours is 1.46m at 2:15pm Thursday 21 January 2021.

Highest level recorded at this location

2.72m on 30 October 2000

View nearby measuring stations