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

Check for flood warnings in this area

Latest recorded level 0.23m at 12:00pm Saturday 19 January 2019.

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
2019-01-19T12:00Z	0.234	false
2019-01-19T11:45Z	0.245	false
2019-01-19T11:30Z	0.25	false
2019-01-19T11:15Z	0.246	false
2019-01-19T11:00Z	0.242	false
2019-01-19T10:45Z	0.27	false
2019-01-19T10:30Z	0.249	false
2019-01-19T10:15Z	0.252	false
2019-01-19T10:00Z	0.254	false
2019-01-19T09:45Z	0.253	false
2019-01-19T09:30Z	0.251	false
2019-01-19T09:15Z	0.266	false
2019-01-19T09:00Z	0.251	false
2019-01-19T08:45Z	0.253	false
2019-01-19T08:30Z	0.25	false
2019-01-19T08:15Z	0.251	false
2019-01-19T08:00Z	0.249	false
2019-01-19T07:45Z	0.251	false
2019-01-19T07:30Z	0.25	false
2019-01-19T07:15Z	0.251	false
2019-01-19T07:00Z	0.253	false
2019-01-19T06:45Z	0.254	false
2019-01-19T06:30Z	0.252	false
2019-01-19T06:15Z	0.253	false
2019-01-19T06:00Z	0.252	false
2019-01-19T05:45Z	0.255	false
2019-01-19T05:30Z	0.253	false
2019-01-19T05:15Z	0.253	false
2019-01-19T05:00Z	0.253	false
2019-01-19T04:45Z	0.253	false
2019-01-19T04:30Z	0.254	false
2019-01-19T04:15Z	0.253	false
2019-01-19T04:00Z	0.253	false
2019-01-19T03:45Z	0.252	false
2019-01-19T03:30Z	0.254	false
2019-01-19T03:15Z	0.253	false
2019-01-19T03:00Z	0.254	false
2019-01-19T02:45Z	0.254	false
2019-01-19T02:30Z	0.254	false
2019-01-19T02:15Z	0.254	false
2019-01-19T02:00Z	0.253	false
2019-01-19T01:45Z	0.253	false
2019-01-19T01:30Z	0.254	false
2019-01-19T01:15Z	0.254	false
2019-01-19T01:00Z	0.254	false
2019-01-19T00:45Z	0.255	false
2019-01-19T00:30Z	0.255	false
2019-01-19T00:15Z	0.253	false
2019-01-19T00:00Z	0.255	false
2019-01-18T23:45Z	0.256	false
2019-01-18T23:30Z	0.255	false
2019-01-18T23:15Z	0.255	false
2019-01-18T23:00Z	0.255	false
2019-01-18T22:45Z	0.254	false
2019-01-18T22:30Z	0.256	false
2019-01-18T22:15Z	0.254	false
2019-01-18T22:00Z	0.255	false
2019-01-18T21:45Z	0.257	false
2019-01-18T21:30Z	0.26	false
2019-01-18T21:15Z	0.263	false
2019-01-18T21:00Z	0.265	false
2019-01-18T20:45Z	0.271	false
2019-01-18T20:30Z	0.286	false
2019-01-18T20:15Z	0.292	false
2019-01-18T20:00Z	0.304	false
2019-01-18T19:45Z	0.311	false
2019-01-18T19:30Z	0.333	false
2019-01-18T19:15Z	0.345	false
2019-01-18T19:00Z	0.344	false
2019-01-18T18:45Z	0.343	false
2019-01-18T18:30Z	0.343	false
2019-01-18T18:15Z	0.34	false
2019-01-18T18:00Z	0.338	false
2019-01-18T17:45Z	0.334	false
2019-01-18T17:30Z	0.327	false
2019-01-18T17:15Z	0.315	false
2019-01-18T17:00Z	0.299	false
2019-01-18T16:45Z	0.292	false
2019-01-18T16:30Z	0.283	false
2019-01-18T16:15Z	0.271	false
2019-01-18T16:00Z	0.257	false
2019-01-18T15:45Z	0.259	false
2019-01-18T15:30Z	0.248	false
2019-01-18T15:15Z	0.229	false
2019-01-18T15:00Z	0.229	false
2019-01-18T14:45Z	0.23	false
2019-01-18T14:30Z	0.231	false
2019-01-18T14:15Z	0.23	false
2019-01-18T14:00Z	0.231	false
2019-01-18T13:45Z	0.233	false
2019-01-18T13:30Z	0.228	false
2019-01-18T13:15Z	0.238	false
2019-01-18T13:00Z	0.234	false
2019-01-18T12:45Z	0.221	false
2019-01-18T12:30Z	0.236	false
2019-01-18T12:15Z	0.233	false
2019-01-18T12:00Z	0.242	false
2019-01-18T11:45Z	0.25	false
2019-01-18T11:30Z	0.245	false
2019-01-18T11:15Z	0.254	false
2019-01-18T11:00Z	0.254	false
2019-01-18T10:45Z	0.253	false
2019-01-18T10:30Z	0.254	false
2019-01-18T10:15Z	0.253	false
2019-01-18T10:00Z	0.254	false
2019-01-18T09:45Z	0.254	false
2019-01-18T09:30Z	0.254	false
2019-01-18T09:15Z	0.254	false
2019-01-18T09:00Z	0.255	false
2019-01-18T08:45Z	0.254	false
2019-01-18T08:30Z	0.253	false
2019-01-18T08:15Z	0.252	false
2019-01-18T08:00Z	0.251	false
2019-01-18T07:45Z	0.25	false
2019-01-18T07:30Z	0.245	false
2019-01-18T07:15Z	0.242	false
2019-01-18T07:00Z	0.236	false
2019-01-18T06:45Z	0.235	false
2019-01-18T06:30Z	0.236	false
2019-01-18T06:15Z	0.236	false
2019-01-18T06:00Z	0.237	false
2019-01-18T05:45Z	0.236	false
2019-01-18T05:30Z	0.238	false
2019-01-18T05:15Z	0.237	false
2019-01-18T05:00Z	0.237	false
2019-01-18T04:45Z	0.238	false
2019-01-18T04:30Z	0.238	false
2019-01-18T04:15Z	0.238	false
2019-01-18T04:00Z	0.239	false
2019-01-18T03:45Z	0.239	false
2019-01-18T03:30Z	0.239	false
2019-01-18T03:15Z	0.24	false
2019-01-18T03:00Z	0.239	false
2019-01-18T02:45Z	0.239	false
2019-01-18T02:30Z	0.239	false
2019-01-18T02:15Z	0.239	false
2019-01-18T02:00Z	0.239	false
2019-01-18T01:45Z	0.239	false
2019-01-18T01:30Z	0.239	false
2019-01-18T01:15Z	0.239	false
2019-01-18T01:00Z	0.239	false
2019-01-18T00:45Z	0.239	false
2019-01-18T00:30Z	0.239	false
2019-01-18T00:15Z	0.239	false
2019-01-18T00:00Z	0.24	false
2019-01-17T23:45Z	0.239	false
2019-01-17T23:30Z	0.239	false
2019-01-17T23:15Z	0.239	false
2019-01-17T23:00Z	0.239	false
2019-01-17T22:45Z	0.239	false
2019-01-17T22:30Z	0.239	false
2019-01-17T22:15Z	0.239	false
2019-01-17T22:00Z	0.239	false
2019-01-17T21:45Z	0.24	false
2019-01-17T21:30Z	0.24	false
2019-01-17T21:15Z	0.241	false
2019-01-17T21:00Z	0.242	false
2019-01-17T20:45Z	0.244	false
2019-01-17T20:30Z	0.246	false
2019-01-17T20:15Z	0.248	false
2019-01-17T20:00Z	0.252	false
2019-01-17T19:45Z	0.258	false
2019-01-17T19:30Z	0.267	false
2019-01-17T19:15Z	0.274	false
2019-01-17T19:00Z	0.292	false
2019-01-17T18:45Z	0.301	false
2019-01-17T18:30Z	0.328	false
2019-01-17T18:15Z	0.326	false
2019-01-17T18:00Z	0.345	false
2019-01-17T17:45Z	0.342	false
2019-01-17T17:30Z	0.338	false
2019-01-17T17:15Z	0.331	false
2019-01-17T17:00Z	0.316	false
2019-01-17T16:45Z	0.304	false
2019-01-17T16:30Z	0.282	false
2019-01-17T16:15Z	0.265	false
2019-01-17T16:00Z	0.257	false
2019-01-17T15:45Z	0.254	false
2019-01-17T15:30Z	0.244	false
2019-01-17T15:15Z	0.238	false
2019-01-17T15:00Z	0.236	false
2019-01-17T14:45Z	0.239	false
2019-01-17T14:30Z	0.234	false
2019-01-17T14:15Z	0.236	false
2019-01-17T14:00Z	0.235	false
2019-01-17T13:45Z	0.237	false
2019-01-17T13:30Z	0.239	false
2019-01-17T13:15Z	0.24	false
2019-01-17T13:00Z	0.24	false
2019-01-17T12:45Z	0.238	false
2019-01-17T12:30Z	0.24	false
2019-01-17T12:15Z	0.239	false
2019-01-17T12:00Z	0.249	false
2019-01-17T11:45Z	0.245	false
2019-01-17T11:30Z	0.257	false
2019-01-17T11:15Z	0.257	false
2019-01-17T11:00Z	0.268	false
2019-01-17T10:45Z	0.264	false
2019-01-17T10:30Z	0.274	false
2019-01-17T10:15Z	0.276	false
2019-01-17T10:00Z	0.273	false
2019-01-17T09:45Z	0.274	false
2019-01-17T09:30Z	0.276	false
2019-01-17T09:15Z	0.272	false
2019-01-17T09:00Z	0.276	false
2019-01-17T08:45Z	0.278	false
2019-01-17T08:30Z	0.277	false
2019-01-17T08:15Z	0.283	false
2019-01-17T08:00Z	0.277	false
2019-01-17T07:45Z	0.275	false
2019-01-17T07:30Z	0.276	false
2019-01-17T07:15Z	0.278	false
2019-01-17T07:00Z	0.277	false
2019-01-17T06:45Z	0.28	false
2019-01-17T06:30Z	0.278	false
2019-01-17T06:15Z	0.279	false
2019-01-17T06:00Z	0.279	false
2019-01-17T05:45Z	0.279	false
2019-01-17T05:30Z	0.28	false
2019-01-17T05:15Z	0.279	false
2019-01-17T05:00Z	0.279	false
2019-01-17T04:45Z	0.279	false
2019-01-17T04:30Z	0.28	false
2019-01-17T04:15Z	0.279	false
2019-01-17T04:00Z	0.281	false
2019-01-17T03:45Z	0.281	false
2019-01-17T03:30Z	0.28	false
2019-01-17T03:15Z	0.281	false
2019-01-17T03:00Z	0.28	false
2019-01-17T02:45Z	0.28	false
2019-01-17T02:30Z	0.279	false
2019-01-17T02:15Z	0.279	false
2019-01-17T02:00Z	0.279	false
2019-01-17T01:45Z	0.278	false
2019-01-17T01:30Z	0.277	false
2019-01-17T01:15Z	0.278	false
2019-01-17T01:00Z	0.278	false
2019-01-17T00:45Z	0.277	false
2019-01-17T00:30Z	0.277	false
2019-01-17T00:15Z	0.277	false
2019-01-17T00:00Z	0.277	false
2019-01-16T23:45Z	0.277	false
2019-01-16T23:30Z	0.276	false
2019-01-16T23:15Z	0.276	false
2019-01-16T23:00Z	0.277	false
2019-01-16T22:45Z	0.277	false
2019-01-16T22:30Z	0.276	false
2019-01-16T22:15Z	0.275	false
2019-01-16T22:00Z	0.275	false
2019-01-16T21:45Z	0.275	false
2019-01-16T21:30Z	0.275	false
2019-01-16T21:15Z	0.274	false
2019-01-16T21:00Z	0.273	false
2019-01-16T20:45Z	0.274	false
2019-01-16T20:30Z	0.272	false
2019-01-16T20:15Z	0.272	false
2019-01-16T20:00Z	0.272	false
2019-01-16T19:45Z	0.271	false
2019-01-16T19:30Z	0.27	false
2019-01-16T19:15Z	0.271	false
2019-01-16T19:00Z	0.269	false
2019-01-16T18:45Z	0.269	false
2019-01-16T18:30Z	0.269	false
2019-01-16T18:15Z	0.27	false
2019-01-16T18:00Z	0.269	false
2019-01-16T17:45Z	0.268	false
2019-01-16T17:30Z	0.268	false
2019-01-16T17:15Z	0.269	false
2019-01-16T17:00Z	0.268	false
2019-01-16T16:45Z	0.267	false
2019-01-16T16:30Z	0.269	false
2019-01-16T16:15Z	0.268	false
2019-01-16T16:00Z	0.266	false
2019-01-16T15:45Z	0.267	false
2019-01-16T15:30Z	0.264	false
2019-01-16T15:15Z	0.267	false
2019-01-16T15:00Z	0.265	false
2019-01-16T14:45Z	0.261	false
2019-01-16T14:30Z	0.26	false
2019-01-16T14:15Z	0.261	false
2019-01-16T14:00Z	0.261	false
2019-01-16T13:45Z	0.259	false
2019-01-16T13:30Z	0.259	false
2019-01-16T13:15Z	0.257	false
2019-01-16T13:00Z	0.258	false
2019-01-16T12:45Z	0.257	false
2019-01-16T12:30Z	0.259	false
2019-01-16T12:15Z	0.258	false
2019-01-16T12:00Z	0.256	false
2019-01-16T11:45Z	0.258	false
2019-01-16T11:30Z	0.295	false
2019-01-16T11:15Z	0.255	false
2019-01-16T11:00Z	0.257	false
2019-01-16T10:45Z	0.256	false
2019-01-16T10:30Z	0.253	false
2019-01-16T10:15Z	0.256	false
2019-01-16T10:00Z	0.254	false
2019-01-16T09:45Z	0.254	false
2019-01-16T09:30Z	0.254	false
2019-01-16T09:15Z	0.254	false
2019-01-16T09:00Z	0.256	false
2019-01-16T08:45Z	0.255	false
2019-01-16T08:30Z	0.253	false
2019-01-16T08:15Z	0.254	false
2019-01-16T08:00Z	0.253	false
2019-01-16T07:45Z	0.253	false
2019-01-16T07:30Z	0.255	false
2019-01-16T07:15Z	0.254	false
2019-01-16T07:00Z	0.253	false
2019-01-16T06:45Z	0.254	false
2019-01-16T06:30Z	0.254	false
2019-01-16T06:15Z	0.252	false
2019-01-16T06:00Z	0.252	false
2019-01-16T05:45Z	0.251	false
2019-01-16T05:30Z	0.252	false
2019-01-16T05:15Z	0.252	false
2019-01-16T05:00Z	0.251	false
2019-01-16T04:45Z	0.252	false
2019-01-16T04:30Z	0.252	false
2019-01-16T04:15Z	0.251	false
2019-01-16T04:00Z	0.253	false
2019-01-16T03:45Z	0.252	false
2019-01-16T03:30Z	0.251	false
2019-01-16T03:15Z	0.252	false
2019-01-16T03:00Z	0.254	false
2019-01-16T02:45Z	0.253	false
2019-01-16T02:30Z	0.251	false
2019-01-16T02:15Z	0.25	false
2019-01-16T02:00Z	0.252	false
2019-01-16T01:45Z	0.254	false
2019-01-16T01:30Z	0.254	false
2019-01-16T01:15Z	0.252	false
2019-01-16T01:00Z	0.252	false
2019-01-16T00:45Z	0.253	false
2019-01-16T00:30Z	0.253	false
2019-01-16T00:15Z	0.255	false
2019-01-16T00:00Z	0.254	false
2019-01-15T23:45Z	0.254	false
2019-01-15T23:30Z	0.253	false
2019-01-15T23:15Z	0.254	false
2019-01-15T23:00Z	0.253	false
2019-01-15T22:45Z	0.255	false
2019-01-15T22:30Z	0.257	false
2019-01-15T22:15Z	0.257	false
2019-01-15T22:00Z	0.257	false
2019-01-15T21:45Z	0.257	false
2019-01-15T21:30Z	0.258	false
2019-01-15T21:15Z	0.259	false
2019-01-15T21:00Z	0.257	false
2019-01-15T20:45Z	0.259	false
2019-01-15T20:30Z	0.259	false
2019-01-15T20:15Z	0.261	false
2019-01-15T20:00Z	0.261	false
2019-01-15T19:45Z	0.261	false
2019-01-15T19:30Z	0.261	false
2019-01-15T19:15Z	0.263	false
2019-01-15T19:00Z	0.262	false
2019-01-15T18:45Z	0.263	false
2019-01-15T18:30Z	0.263	false
2019-01-15T18:15Z	0.264	false
2019-01-15T18:00Z	0.265	false
2019-01-15T17:45Z	0.264	false
2019-01-15T17:30Z	0.266	false
2019-01-15T17:15Z	0.268	false
2019-01-15T17:00Z	0.266	false
2019-01-15T16:45Z	0.266	false
2019-01-15T16:30Z	0.266	false
2019-01-15T16:15Z	0.266	false
2019-01-15T16:00Z	0.266	false
2019-01-15T15:45Z	0.265	false
2019-01-15T15:30Z	0.267	false
2019-01-15T15:15Z	0.265	false
2019-01-15T15:00Z	0.266	false
2019-01-15T14:45Z	0.267	false
2019-01-15T14:30Z	0.266	false
2019-01-15T14:15Z	0.267	false
2019-01-15T14:00Z	0.267	false
2019-01-15T13:45Z	0.265	false
2019-01-15T13:30Z	0.265	false
2019-01-15T13:15Z	0.266	false
2019-01-15T13:00Z	0.267	false
2019-01-15T12:45Z	0.264	false
2019-01-15T12:30Z	0.265	false
2019-01-15T12:15Z	0.264	false
2019-01-15T12:00Z	0.272	false
2019-01-15T11:45Z	0.255	false
2019-01-15T11:30Z	0.268	false
2019-01-15T11:15Z	0.267	false
2019-01-15T11:00Z	0.266	false
2019-01-15T10:45Z	0.265	false
2019-01-15T10:30Z	0.266	false
2019-01-15T10:15Z	0.268	false
2019-01-15T10:00Z	0.266	false
2019-01-15T09:45Z	0.267	false
2019-01-15T09:30Z	0.265	false
2019-01-15T09:15Z	0.263	false
2019-01-15T09:00Z	0.266	false
2019-01-15T08:45Z	0.265	false
2019-01-15T08:30Z	0.265	false
2019-01-15T08:15Z	0.267	false
2019-01-15T08:00Z	0.27	false
2019-01-15T07:45Z	0.268	false
2019-01-15T07:30Z	0.27	false
2019-01-15T07:15Z	0.27	false
2019-01-15T07:00Z	0.269	false
2019-01-15T06:45Z	0.269	false
2019-01-15T06:30Z	0.269	false
2019-01-15T06:15Z	0.27	false
2019-01-15T06:00Z	0.272	false
2019-01-15T05:45Z	0.27	false
2019-01-15T05:30Z	0.271	false
2019-01-15T05:15Z	0.272	false
2019-01-15T05:00Z	0.272	false
2019-01-15T04:45Z	0.272	false
2019-01-15T04:30Z	0.272	false
2019-01-15T04:15Z	0.272	false
2019-01-15T04:00Z	0.273	false
2019-01-15T03:45Z	0.272	false
2019-01-15T03:30Z	0.273	false
2019-01-15T03:15Z	0.274	false
2019-01-15T03:00Z	0.274	false
2019-01-15T02:45Z	0.274	false
2019-01-15T02:30Z	0.274	false
2019-01-15T02:15Z	0.274	false
2019-01-15T02:00Z	0.273	false
2019-01-15T01:45Z	0.273	false
2019-01-15T01:30Z	0.274	false
2019-01-15T01:15Z	0.275	false
2019-01-15T01:00Z	0.275	false
2019-01-15T00:45Z	0.275	false
2019-01-15T00:30Z	0.274	false
2019-01-15T00:15Z	0.273	false
2019-01-15T00:00Z	0.274	false
2019-01-14T23:45Z	0.273	false
2019-01-14T23:30Z	0.273	false
2019-01-14T23:15Z	0.273	false
2019-01-14T23:00Z	0.274	false
2019-01-14T22:45Z	0.272	false
2019-01-14T22:30Z	0.273	false
2019-01-14T22:15Z	0.273	false
2019-01-14T22:00Z	0.272	false
2019-01-14T21:45Z	0.274	false
2019-01-14T21:30Z	0.273	false
2019-01-14T21:15Z	0.273	false
2019-01-14T21:00Z	0.274	false
2019-01-14T20:45Z	0.275	false
2019-01-14T20:30Z	0.274	false
2019-01-14T20:15Z	0.277	false
2019-01-14T20:00Z	0.279	false
2019-01-14T19:45Z	0.282	false
2019-01-14T19:30Z	0.285	false
2019-01-14T19:15Z	0.29	false
2019-01-14T19:00Z	0.295	false
2019-01-14T18:45Z	0.311	false
2019-01-14T18:30Z	0.332	false
2019-01-14T18:15Z	0.343	false
2019-01-14T18:00Z	0.34	false
2019-01-14T17:45Z	0.337	false
2019-01-14T17:30Z	0.332	false
2019-01-14T17:15Z	0.326	false
2019-01-14T17:00Z	0.312	false
2019-01-14T16:45Z	0.299	false
2019-01-14T16:30Z	0.282	false
2019-01-14T16:15Z	0.258	false
2019-01-14T16:00Z	0.274	false
2019-01-14T15:45Z	0.277	false
2019-01-14T15:30Z	0.278	false
2019-01-14T15:15Z	0.276	false
2019-01-14T15:00Z	0.273	false
2019-01-14T14:45Z	0.274	false
2019-01-14T14:30Z	0.27	false
2019-01-14T14:15Z	0.271	false
2019-01-14T14:00Z	0.262	false
2019-01-14T13:45Z	0.291	false
2019-01-14T13:30Z	0.27	false
2019-01-14T13:15Z	0.266	false
2019-01-14T13:00Z	0.271	false
2019-01-14T12:45Z	0.265	false
2019-01-14T12:30Z	0.266	false
2019-01-14T12:15Z	0.27	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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