River level River Thames at Old Windsor Lock (upstream data)

Flooding is possible - Be prepared

The latest information indicates flooding is possible - Take action.

Check for flood warnings in this area

Latest recorded level 0.84m at 7:00pm Tuesday 18 February 2020.

View downstream data for this station

Why are there 2 sets of data for this station?

Some monitoring stations are located near to a man-made structure which affects the river's flow characteristics, for example a weir, or lock. For these stations, we provide river levels from both the upstream and downstream sides of the structure.

River levels at this location in the last 5 days

Now
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• Measured level
• When the water level reaches 0.35m here, minor flooding is possible in this area
• Highest recorded level. Hide
• Show highest recorded level

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Observed data

DateTime	Value	Error
2020-02-18T19:00Z	0.84	false
2020-02-18T18:45Z	0.832	false
2020-02-18T18:30Z	0.818	false
2020-02-18T18:15Z	0.812	false
2020-02-18T18:00Z	0.823	false
2020-02-18T17:45Z	0.822	false
2020-02-18T17:30Z	0.817	false
2020-02-18T17:15Z	0.812	false
2020-02-18T17:00Z	0.815	false
2020-02-18T16:45Z	0.817	false
2020-02-18T16:30Z	0.807	false
2020-02-18T16:15Z	0.826	false
2020-02-18T16:00Z	0.811	false
2020-02-18T15:45Z	0.8	false
2020-02-18T15:30Z	0.798	false
2020-02-18T15:15Z	0.799	false
2020-02-18T15:00Z	0.784	false
2020-02-18T14:45Z	0.79	false
2020-02-18T14:30Z	0.763	false
2020-02-18T14:15Z	0.784	false
2020-02-18T14:00Z	0.76	false
2020-02-18T13:45Z	0.786	false
2020-02-18T13:30Z	0.76	false
2020-02-18T13:15Z	0.769	false
2020-02-18T13:00Z	0.77	false
2020-02-18T12:45Z	0.772	false
2020-02-18T12:30Z	0.785	false
2020-02-18T12:15Z	0.771	false
2020-02-18T12:00Z	0.781	false
2020-02-18T11:45Z	0.787	false
2020-02-18T11:30Z	0.776	false
2020-02-18T11:15Z	0.786	false
2020-02-18T11:00Z	0.791	false
2020-02-18T10:45Z	0.812	false
2020-02-18T10:30Z	0.79	false
2020-02-18T10:15Z	0.8	false
2020-02-18T10:00Z	0.798	false
2020-02-18T09:45Z	0.776	false
2020-02-18T09:30Z	0.782	false
2020-02-18T09:15Z	0.78	false
2020-02-18T09:00Z	0.777	false
2020-02-18T08:45Z	0.792	false
2020-02-18T08:30Z	0.777	false
2020-02-18T08:15Z	0.782	false
2020-02-18T08:00Z	0.765	false
2020-02-18T07:45Z	0.767	false
2020-02-18T07:30Z	0.785	false
2020-02-18T07:15Z	0.783	false
2020-02-18T07:00Z	0.775	false
2020-02-18T06:45Z	0.772	false
2020-02-18T06:30Z	0.772	false
2020-02-18T06:15Z	0.769	false
2020-02-18T06:00Z	0.788	false
2020-02-18T05:45Z	0.768	false
2020-02-18T05:30Z	0.767	false
2020-02-18T05:15Z	0.78	false
2020-02-18T05:00Z	0.751	false
2020-02-18T04:45Z	0.776	false
2020-02-18T04:30Z	0.748	false
2020-02-18T04:15Z	0.754	false
2020-02-18T04:00Z	0.751	false
2020-02-18T03:45Z	0.727	false
2020-02-18T03:30Z	0.737	false
2020-02-18T03:15Z	0.737	false
2020-02-18T03:00Z	0.741	false
2020-02-18T02:45Z	0.735	false
2020-02-18T02:30Z	0.721	false
2020-02-18T02:15Z	0.731	false
2020-02-18T02:00Z	0.719	false
2020-02-18T01:45Z	0.723	false
2020-02-18T01:30Z	0.725	false
2020-02-18T01:15Z	0.737	false
2020-02-18T01:00Z	0.716	false
2020-02-18T00:45Z	0.722	false
2020-02-18T00:30Z	0.719	false
2020-02-18T00:15Z	0.718	false
2020-02-18T00:00Z	0.729	false
2020-02-17T23:45Z	0.722	false
2020-02-17T23:30Z	0.73	false
2020-02-17T23:15Z	0.711	false
2020-02-17T23:00Z	0.709	false
2020-02-17T22:45Z	0.73	false
2020-02-17T22:30Z	0.7	false
2020-02-17T22:15Z	0.708	false
2020-02-17T22:00Z	0.695	false
2020-02-17T21:45Z	0.678	false
2020-02-17T21:30Z	0.682	false
2020-02-17T21:15Z	0.684	false
2020-02-17T21:00Z	0.684	false
2020-02-17T20:45Z	0.681	false
2020-02-17T20:30Z	0.679	false
2020-02-17T20:15Z	0.685	false
2020-02-17T20:00Z	0.703	false
2020-02-17T19:45Z	0.689	false
2020-02-17T19:30Z	0.691	false
2020-02-17T19:15Z	0.694	false
2020-02-17T19:00Z	0.697	false
2020-02-17T18:45Z	0.71	false
2020-02-17T18:30Z	0.697	false
2020-02-17T18:15Z	0.697	false
2020-02-17T18:00Z	0.708	false
2020-02-17T17:45Z	0.701	false
2020-02-17T17:30Z	0.69	false
2020-02-17T17:15Z	0.677	false
2020-02-17T17:00Z	0.675	false
2020-02-17T16:45Z	0.669	false
2020-02-17T16:30Z	0.668	false
2020-02-17T16:15Z	0.659	false
2020-02-17T16:00Z	0.66	false
2020-02-17T15:45Z	0.656	false
2020-02-17T15:30Z	0.662	false
2020-02-17T15:15Z	0.646	false
2020-02-17T15:00Z	0.643	false
2020-02-17T14:45Z	0.645	false
2020-02-17T14:30Z	0.648	false
2020-02-17T14:15Z	0.626	false
2020-02-17T14:00Z	0.622	false
2020-02-17T13:45Z	0.62	false
2020-02-17T13:30Z	0.604	false
2020-02-17T13:15Z	0.585	false
2020-02-17T13:00Z	0.579	false
2020-02-17T12:45Z	0.569	false
2020-02-17T12:30Z	0.552	false
2020-02-17T12:15Z	0.565	false
2020-02-17T12:00Z	0.544	false
2020-02-17T11:45Z	0.55	false
2020-02-17T11:30Z	0.554	false
2020-02-17T11:15Z	0.541	false
2020-02-17T11:00Z	0.553	false
2020-02-17T10:45Z	0.547	false
2020-02-17T10:30Z	0.573	false
2020-02-17T10:15Z	0.554	false
2020-02-17T10:00Z	0.552	false
2020-02-17T09:45Z	0.564	false
2020-02-17T09:30Z	0.582	false
2020-02-17T09:15Z	0.6	false
2020-02-17T09:00Z	0.61	false
2020-02-17T08:45Z	0.639	false
2020-02-17T08:30Z	0.614	false
2020-02-17T08:15Z	0.622	false
2020-02-17T08:00Z	0.63	false
2020-02-17T07:45Z	0.629	false
2020-02-17T07:30Z	0.635	false
2020-02-17T07:15Z	0.624	false
2020-02-17T07:00Z	0.629	false
2020-02-17T06:45Z	0.611	false
2020-02-17T06:30Z	0.616	false
2020-02-17T06:15Z	0.612	false
2020-02-17T06:00Z	0.605	false
2020-02-17T05:45Z	0.601	false
2020-02-17T05:30Z	0.609	false
2020-02-17T05:15Z	0.599	false
2020-02-17T05:00Z	0.609	false
2020-02-17T04:45Z	0.628	false
2020-02-17T04:30Z	0.614	false
2020-02-17T04:15Z	0.607	false
2020-02-17T04:00Z	0.612	false
2020-02-17T03:45Z	0.606	false
2020-02-17T03:30Z	0.607	false
2020-02-17T03:15Z	0.606	false
2020-02-17T03:00Z	0.608	false
2020-02-17T02:45Z	0.615	false
2020-02-17T02:30Z	0.612	false
2020-02-17T02:15Z	0.609	false
2020-02-17T02:00Z	0.612	false
2020-02-17T01:45Z	0.603	false
2020-02-17T01:30Z	0.6	false
2020-02-17T01:15Z	0.605	false
2020-02-17T01:00Z	0.6	false
2020-02-17T00:45Z	0.609	false
2020-02-17T00:30Z	0.588	false
2020-02-17T00:15Z	0.578	false
2020-02-17T00:00Z	0.584	false
2020-02-16T23:45Z	0.588	false
2020-02-16T23:30Z	0.581	false
2020-02-16T23:15Z	0.579	false
2020-02-16T23:00Z	0.576	false
2020-02-16T22:45Z	0.579	false
2020-02-16T22:30Z	0.584	false
2020-02-16T22:15Z	0.59	false
2020-02-16T22:00Z	0.579	false
2020-02-16T21:45Z	0.581	false
2020-02-16T21:30Z	0.591	false
2020-02-16T21:15Z	0.583	false
2020-02-16T21:00Z	0.582	false
2020-02-16T20:45Z	0.573	false
2020-02-16T20:30Z	0.566	false
2020-02-16T20:15Z	0.563	false
2020-02-16T20:00Z	0.554	false
2020-02-16T19:45Z	0.548	false
2020-02-16T19:30Z	0.532	false
2020-02-16T19:15Z	0.531	false
2020-02-16T19:00Z	0.544	false
2020-02-16T18:45Z	0.528	false
2020-02-16T18:30Z	0.516	false
2020-02-16T18:15Z	0.534	false
2020-02-16T18:00Z	0.528	false
2020-02-16T17:45Z	0.519	false
2020-02-16T17:30Z	0.501	false
2020-02-16T17:15Z	0.514	false
2020-02-16T17:00Z	0.509	false
2020-02-16T16:45Z	0.505	false
2020-02-16T16:30Z	0.507	false
2020-02-16T16:15Z	0.499	false
2020-02-16T16:00Z	0.487	false
2020-02-16T15:45Z	0.485	false
2020-02-16T15:30Z	0.464	false
2020-02-16T15:15Z	0.453	false
2020-02-16T15:00Z	0.452	false
2020-02-16T14:45Z	0.441	false
2020-02-16T14:30Z	0.454	false
2020-02-16T14:15Z	0.448	false
2020-02-16T14:00Z	0.433	false
2020-02-16T13:45Z	0.446	false
2020-02-16T13:30Z	0.425	false
2020-02-16T13:15Z	0.433	false
2020-02-16T13:00Z	0.442	false
2020-02-16T12:45Z	0.432	false
2020-02-16T12:30Z	0.426	false
2020-02-16T12:15Z	0.419	false
2020-02-16T12:00Z	0.406	false
2020-02-16T11:45Z	0.4	false
2020-02-16T11:30Z	0.402	false
2020-02-16T11:15Z	0.399	false
2020-02-16T11:00Z	0.391	false
2020-02-16T10:45Z	0.391	false
2020-02-16T10:30Z	0.386	false
2020-02-16T10:15Z	0.385	false
2020-02-16T10:00Z	0.384	false
2020-02-16T09:45Z	0.364	false
2020-02-16T09:30Z	0.381	false
2020-02-16T09:15Z	0.362	false
2020-02-16T09:00Z	0.373	false
2020-02-16T08:45Z	0.38	false
2020-02-16T08:30Z	0.361	false
2020-02-16T08:15Z	0.362	false
2020-02-16T08:00Z	0.358	false
2020-02-16T07:45Z	0.357	false
2020-02-16T07:30Z	0.363	false
2020-02-16T07:15Z	0.355	false
2020-02-16T07:00Z	0.35	false
2020-02-16T06:45Z	0.341	false
2020-02-16T06:30Z	0.339	false
2020-02-16T06:15Z	0.334	false
2020-02-16T06:00Z	0.342	false
2020-02-16T05:45Z	0.343	false
2020-02-16T05:30Z	0.328	false
2020-02-16T05:15Z	0.335	false
2020-02-16T05:00Z	0.319	false
2020-02-16T04:45Z	0.321	false
2020-02-16T04:30Z	0.333	false
2020-02-16T04:15Z	0.329	false
2020-02-16T04:00Z	0.329	false
2020-02-16T03:45Z	0.319	false
2020-02-16T03:30Z	0.328	false
2020-02-16T03:15Z	0.327	false
2020-02-16T03:00Z	0.311	false
2020-02-16T02:45Z	0.311	false
2020-02-16T02:30Z	0.315	false
2020-02-16T02:15Z	0.315	false
2020-02-16T02:00Z	0.312	false
2020-02-16T01:45Z	0.316	false
2020-02-16T01:30Z	0.313	false
2020-02-16T01:15Z	0.305	false
2020-02-16T01:00Z	0.3	false
2020-02-16T00:45Z	0.311	false
2020-02-16T00:30Z	0.311	false
2020-02-16T00:15Z	0.303	false
2020-02-16T00:00Z	0.315	false
2020-02-15T23:45Z	0.306	false
2020-02-15T23:30Z	0.332	false
2020-02-15T23:15Z	0.307	false
2020-02-15T23:00Z	0.309	false
2020-02-15T22:45Z	0.314	false
2020-02-15T22:30Z	0.312	false
2020-02-15T22:15Z	0.308	false
2020-02-15T22:00Z	0.309	false
2020-02-15T21:45Z	0.314	false
2020-02-15T21:30Z	0.303	false
2020-02-15T21:15Z	0.316	false
2020-02-15T21:00Z	0.308	false
2020-02-15T20:45Z	0.308	false
2020-02-15T20:30Z	0.322	false
2020-02-15T20:15Z	0.305	false
2020-02-15T20:00Z	0.309	false
2020-02-15T19:45Z	0.302	false
2020-02-15T19:30Z	0.297	false
2020-02-15T19:15Z	0.301	false
2020-02-15T19:00Z	0.292	false
2020-02-15T18:45Z	0.296	false
2020-02-15T18:30Z	0.3	false
2020-02-15T18:15Z	0.295	false
2020-02-15T18:00Z	0.288	false
2020-02-15T17:45Z	0.283	false
2020-02-15T17:30Z	0.296	false
2020-02-15T17:15Z	0.276	false
2020-02-15T17:00Z	0.28	false
2020-02-15T16:45Z	0.275	false
2020-02-15T16:30Z	0.272	false
2020-02-15T16:15Z	0.261	false
2020-02-15T16:00Z	0.268	false
2020-02-15T15:45Z	0.252	false
2020-02-15T15:30Z	0.253	false
2020-02-15T15:15Z	0.263	false
2020-02-15T15:00Z	0.264	false
2020-02-15T14:45Z	0.258	false
2020-02-15T14:30Z	0.254	false
2020-02-15T14:15Z	0.264	false
2020-02-15T14:00Z	0.266	false
2020-02-15T13:45Z	0.257	false
2020-02-15T13:30Z	0.273	false
2020-02-15T13:15Z	0.263	false
2020-02-15T13:00Z	0.287	false
2020-02-15T12:45Z	0.261	false
2020-02-15T12:30Z	0.299	false
2020-02-15T12:15Z	0.286	false
2020-02-15T12:00Z	0.265	false
2020-02-15T11:45Z	0.272	false
2020-02-15T11:30Z	0.249	false
2020-02-15T11:15Z	0.26	false
2020-02-15T11:00Z	0.264	false
2020-02-15T10:45Z	0.247	false
2020-02-15T10:30Z	0.245	false
2020-02-15T10:15Z	0.255	false
2020-02-15T10:00Z	0.256	false
2020-02-15T09:45Z	0.262	false
2020-02-15T09:30Z	0.259	false
2020-02-15T09:15Z	0.26	false
2020-02-15T09:00Z	0.256	false
2020-02-15T08:45Z	0.252	false
2020-02-15T08:30Z	0.25	false
2020-02-15T08:15Z	0.255	false
2020-02-15T08:00Z	0.25	false
2020-02-15T07:45Z	0.257	false
2020-02-15T07:30Z	0.253	false
2020-02-15T07:15Z	0.249	false
2020-02-15T07:00Z	0.236	false
2020-02-15T06:45Z	0.257	false
2020-02-15T06:30Z	0.249	false
2020-02-15T06:15Z	0.253	false
2020-02-15T06:00Z	0.257	false
2020-02-15T05:45Z	0.254	false
2020-02-15T05:30Z	0.254	false
2020-02-15T05:15Z	0.25	false
2020-02-15T05:00Z	0.254	false
2020-02-15T04:45Z	0.251	false
2020-02-15T04:30Z	0.255	false
2020-02-15T04:15Z	0.25	false
2020-02-15T04:00Z	0.268	false
2020-02-15T03:45Z	0.263	false
2020-02-15T03:30Z	0.256	false
2020-02-15T03:15Z	0.249	false
2020-02-15T03:00Z	0.256	false
2020-02-15T02:45Z	0.254	false
2020-02-15T02:30Z	0.246	false
2020-02-15T02:15Z	0.278	false
2020-02-15T02:00Z	0.255	false
2020-02-15T01:45Z	0.259	false
2020-02-15T01:30Z	0.256	false
2020-02-15T01:15Z	0.274	false
2020-02-15T01:00Z	0.269	false
2020-02-15T00:45Z	0.27	false
2020-02-15T00:30Z	0.264	false
2020-02-15T00:15Z	0.272	false
2020-02-15T00:00Z	0.255	false
2020-02-14T23:45Z	0.251	false
2020-02-14T23:30Z	0.259	false
2020-02-14T23:15Z	0.252	false
2020-02-14T23:00Z	0.255	false
2020-02-14T22:45Z	0.261	false
2020-02-14T22:30Z	0.256	false
2020-02-14T22:15Z	0.259	false
2020-02-14T22:00Z	0.253	false
2020-02-14T21:45Z	0.261	false
2020-02-14T21:30Z	0.267	false
2020-02-14T21:15Z	0.248	false
2020-02-14T21:00Z	0.27	false
2020-02-14T20:45Z	0.26	false
2020-02-14T20:30Z	0.263	false
2020-02-14T20:15Z	0.245	false
2020-02-14T20:00Z	0.266	false
2020-02-14T19:45Z	0.273	false
2020-02-14T19:30Z	0.269	false
2020-02-14T19:15Z	0.27	false
2020-02-14T19:00Z	0.269	false
2020-02-14T18:45Z	0.257	false
2020-02-14T18:30Z	0.247	false
2020-02-14T18:15Z	0.258	false
2020-02-14T18:00Z	0.254	false
2020-02-14T17:45Z	0.254	false
2020-02-14T17:30Z	0.25	false
2020-02-14T17:15Z	0.252	false
2020-02-14T17:00Z	0.252	false
2020-02-14T16:45Z	0.241	false
2020-02-14T16:30Z	0.241	false
2020-02-14T16:15Z	0.251	false
2020-02-14T16:00Z	0.258	false
2020-02-14T15:45Z	0.24	false
2020-02-14T15:30Z	0.247	false
2020-02-14T15:15Z	0.241	false
2020-02-14T15:00Z	0.236	false
2020-02-14T14:45Z	0.218	false
2020-02-14T14:30Z	0.255	false
2020-02-14T14:15Z	0.225	false
2020-02-14T14:00Z	0.201	false
2020-02-14T13:45Z	0.177	false
2020-02-14T13:30Z	0.165	false
2020-02-14T13:15Z	0.174	false
2020-02-14T13:00Z	0.175	false
2020-02-14T12:45Z	0.174	false
2020-02-14T12:30Z	0.176	false
2020-02-14T12:15Z	0.18	false
2020-02-14T12:00Z	0.19	false
2020-02-14T11:45Z	0.189	false
2020-02-14T11:30Z	0.201	false
2020-02-14T11:15Z	0.204	false
2020-02-14T11:00Z	0.241	false
2020-02-14T10:45Z	0.248	false
2020-02-14T10:30Z	0.247	false
2020-02-14T10:15Z	0.252	false
2020-02-14T10:00Z	0.24	false
2020-02-14T09:45Z	0.251	false
2020-02-14T09:30Z	0.25	false
2020-02-14T09:15Z	0.245	false
2020-02-14T09:00Z	0.241	false
2020-02-14T08:45Z	0.241	false
2020-02-14T08:30Z	0.249	false
2020-02-14T08:15Z	0.24	false
2020-02-14T08:00Z	0.247	false
2020-02-14T07:45Z	0.238	false
2020-02-14T07:30Z	0.244	false
2020-02-14T07:15Z	0.247	false
2020-02-14T07:00Z	0.248	false
2020-02-14T06:45Z	0.239	false
2020-02-14T06:30Z	0.242	false
2020-02-14T06:15Z	0.241	false
2020-02-14T06:00Z	0.242	false
2020-02-14T05:45Z	0.245	false
2020-02-14T05:30Z	0.241	false
2020-02-14T05:15Z	0.239	false
2020-02-14T05:00Z	0.243	false
2020-02-14T04:45Z	0.238	false
2020-02-14T04:30Z	0.243	false
2020-02-14T04:15Z	0.238	false
2020-02-14T04:00Z	0.236	false
2020-02-14T03:45Z	0.234	false
2020-02-14T03:30Z	0.245	false
2020-02-14T03:15Z	0.238	false
2020-02-14T03:00Z	0.242	false
2020-02-14T02:45Z	0.238	false
2020-02-14T02:30Z	0.236	false
2020-02-14T02:15Z	0.241	false
2020-02-14T02:00Z	0.236	false
2020-02-14T01:45Z	0.237	false
2020-02-14T01:30Z	0.229	false
2020-02-14T01:15Z	0.238	false
2020-02-14T01:00Z	0.236	false
2020-02-14T00:45Z	0.233	false
2020-02-14T00:30Z	0.236	false
2020-02-14T00:15Z	0.235	false
2020-02-14T00:00Z	0.24	false
2020-02-13T23:45Z	0.229	false
2020-02-13T23:30Z	0.227	false
2020-02-13T23:15Z	0.233	false
2020-02-13T23:00Z	0.229	false
2020-02-13T22:45Z	0.225	false
2020-02-13T22:30Z	0.228	false
2020-02-13T22:15Z	0.233	false
2020-02-13T22:00Z	0.238	false
2020-02-13T21:45Z	0.227	false
2020-02-13T21:30Z	0.228	false
2020-02-13T21:15Z	0.231	false
2020-02-13T21:00Z	0.239	false
2020-02-13T20:45Z	0.238	false
2020-02-13T20:30Z	0.231	false
2020-02-13T20:15Z	0.246	false
2020-02-13T20:00Z	0.246	false
2020-02-13T19:45Z	0.257	false
2020-02-13T19:30Z	0.254	false
2020-02-13T19:15Z	0.282	false

Forecast data

Key information

• Station name: Old Windsor Lock (upstream)
• Station ID: 7172
• River name: River Thames
• Typical range: 0.10m to 0.35m
• Highest level on record: 1.94m on 11 February 2014
• Site datum: 16.12mAOD (what does this mean?)

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?

We use measuring stations like this one to collect water level data, usually once or twice a day. We collect data more frequently when there's a greater risk of flooding. That's why the graph might show a short time lag since the last measurement.

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.

• View nearby measuring stations

• View the flood information service for England
• View your property's long term risk of flooding

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