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

Check for flood warnings in this area

Latest recorded level 0.21m at 1:00am Sunday 5 April 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
2020-04-05T00:00Z	0.212	false
2020-04-04T23:45Z	0.209	false
2020-04-04T23:30Z	0.212	false
2020-04-04T23:15Z	0.208	false
2020-04-04T23:00Z	0.205	false
2020-04-04T22:45Z	0.205	false
2020-04-04T22:30Z	0.207	false
2020-04-04T22:15Z	0.205	false
2020-04-04T22:00Z	0.203	false
2020-04-04T21:45Z	0.203	false
2020-04-04T21:30Z	0.203	false
2020-04-04T21:15Z	0.207	false
2020-04-04T21:00Z	0.206	false
2020-04-04T20:45Z	0.21	false
2020-04-04T20:30Z	0.211	false
2020-04-04T20:15Z	0.213	false
2020-04-04T20:00Z	0.213	false
2020-04-04T19:45Z	0.215	false
2020-04-04T19:30Z	0.216	false
2020-04-04T19:15Z	0.22	false
2020-04-04T19:00Z	0.243	false
2020-04-04T18:45Z	0.224	false
2020-04-04T18:30Z	0.228	false
2020-04-04T18:15Z	0.227	false
2020-04-04T18:00Z	0.218	false
2020-04-04T17:45Z	0.22	false
2020-04-04T17:30Z	0.226	false
2020-04-04T17:15Z	0.232	false
2020-04-04T17:00Z	0.234	false
2020-04-04T16:45Z	0.233	false
2020-04-04T16:30Z	0.233	false
2020-04-04T16:15Z	0.228	false
2020-04-04T16:00Z	0.223	false
2020-04-04T15:45Z	0.238	false
2020-04-04T15:30Z	0.234	false
2020-04-04T15:15Z	0.236	false
2020-04-04T15:00Z	0.233	false
2020-04-04T14:45Z	0.235	false
2020-04-04T14:30Z	0.236	false
2020-04-04T14:15Z	0.235	false
2020-04-04T14:00Z	0.236	false
2020-04-04T13:45Z	0.232	false
2020-04-04T13:30Z	0.234	false
2020-04-04T13:15Z	0.234	false
2020-04-04T13:00Z	0.232	false
2020-04-04T12:45Z	0.233	false
2020-04-04T12:30Z	0.234	false
2020-04-04T12:15Z	0.233	false
2020-04-04T12:00Z	0.232	false
2020-04-04T11:45Z	0.234	false
2020-04-04T11:30Z	0.233	false
2020-04-04T11:15Z	0.233	false
2020-04-04T11:00Z	0.231	false
2020-04-04T10:45Z	0.234	false
2020-04-04T10:30Z	0.234	false
2020-04-04T10:15Z	0.234	false
2020-04-04T10:00Z	0.233	false
2020-04-04T09:45Z	0.234	false
2020-04-04T09:30Z	0.233	false
2020-04-04T09:15Z	0.231	false
2020-04-04T09:00Z	0.229	false
2020-04-04T08:45Z	0.221	false
2020-04-04T08:30Z	0.227	false
2020-04-04T08:15Z	0.233	false
2020-04-04T08:00Z	0.234	false
2020-04-04T07:45Z	0.236	false
2020-04-04T07:30Z	0.236	false
2020-04-04T07:15Z	0.234	false
2020-04-04T07:00Z	0.236	false
2020-04-04T06:45Z	0.235	false
2020-04-04T06:30Z	0.237	false
2020-04-04T06:15Z	0.236	false
2020-04-04T06:00Z	0.235	false
2020-04-04T05:45Z	0.237	false
2020-04-04T05:30Z	0.237	false
2020-04-04T05:15Z	0.236	false
2020-04-04T05:00Z	0.238	false
2020-04-04T04:45Z	0.24	false
2020-04-04T04:30Z	0.236	false
2020-04-04T04:15Z	0.238	false
2020-04-04T04:00Z	0.237	false
2020-04-04T03:45Z	0.239	false
2020-04-04T03:30Z	0.238	false
2020-04-04T03:15Z	0.242	false
2020-04-04T03:00Z	0.242	false
2020-04-04T02:45Z	0.24	false
2020-04-04T02:30Z	0.242	false
2020-04-04T02:15Z	0.245	false
2020-04-04T02:00Z	0.242	false
2020-04-04T01:45Z	0.242	false
2020-04-04T01:30Z	0.245	false
2020-04-04T01:15Z	0.244	false
2020-04-04T01:00Z	0.246	false
2020-04-04T00:45Z	0.244	false
2020-04-04T00:30Z	0.245	false
2020-04-04T00:15Z	0.244	false
2020-04-04T00:00Z	0.245	false
2020-04-03T23:45Z	0.245	false
2020-04-03T23:30Z	0.247	false
2020-04-03T23:15Z	0.245	false
2020-04-03T23:00Z	0.244	false
2020-04-03T22:45Z	0.244	false
2020-04-03T22:30Z	0.245	false
2020-04-03T22:15Z	0.247	false
2020-04-03T22:00Z	0.245	false
2020-04-03T21:45Z	0.246	false
2020-04-03T21:30Z	0.248	false
2020-04-03T21:15Z	0.247	false
2020-04-03T21:00Z	0.247	false
2020-04-03T20:45Z	0.247	false
2020-04-03T20:30Z	0.245	false
2020-04-03T20:15Z	0.246	false
2020-04-03T20:00Z	0.244	false
2020-04-03T19:45Z	0.247	false
2020-04-03T19:30Z	0.248	false
2020-04-03T19:15Z	0.243	false
2020-04-03T19:00Z	0.243	false
2020-04-03T18:45Z	0.243	false
2020-04-03T18:30Z	0.244	false
2020-04-03T18:15Z	0.245	false
2020-04-03T18:00Z	0.245	false
2020-04-03T17:45Z	0.245	false
2020-04-03T17:30Z	0.248	false
2020-04-03T17:15Z	0.247	false
2020-04-03T17:00Z	0.244	false
2020-04-03T16:45Z	0.249	false
2020-04-03T16:30Z	0.246	false
2020-04-03T16:15Z	0.243	false
2020-04-03T16:00Z	0.243	false
2020-04-03T15:45Z	0.245	false
2020-04-03T15:30Z	0.243	false
2020-04-03T15:15Z	0.245	false
2020-04-03T15:00Z	0.245	false
2020-04-03T14:45Z	0.245	false
2020-04-03T14:30Z	0.243	false
2020-04-03T14:15Z	0.249	false
2020-04-03T14:00Z	0.244	false
2020-04-03T13:45Z	0.243	false
2020-04-03T13:30Z	0.246	false
2020-04-03T13:15Z	0.244	false
2020-04-03T13:00Z	0.242	false
2020-04-03T12:45Z	0.243	false
2020-04-03T12:30Z	0.246	false
2020-04-03T12:15Z	0.243	false
2020-04-03T12:00Z	0.241	false
2020-04-03T11:45Z	0.246	false
2020-04-03T11:30Z	0.246	false
2020-04-03T11:15Z	0.243	false
2020-04-03T11:00Z	0.242	false
2020-04-03T10:45Z	0.245	false
2020-04-03T10:30Z	0.247	false
2020-04-03T10:15Z	0.272	false
2020-04-03T10:00Z	0.245	false
2020-04-03T09:45Z	0.246	false
2020-04-03T09:30Z	0.246	false
2020-04-03T09:15Z	0.247	false
2020-04-03T09:00Z	0.248	false
2020-04-03T08:45Z	0.245	false
2020-04-03T08:30Z	0.247	false
2020-04-03T08:15Z	0.248	false
2020-04-03T08:00Z	0.249	false
2020-04-03T07:45Z	0.252	false
2020-04-03T07:30Z	0.252	false
2020-04-03T07:15Z	0.25	false
2020-04-03T07:00Z	0.248	false
2020-04-03T06:45Z	0.25	false
2020-04-03T06:30Z	0.253	false
2020-04-03T06:15Z	0.251	false
2020-04-03T06:00Z	0.25	false
2020-04-03T05:45Z	0.247	false
2020-04-03T05:30Z	0.246	false
2020-04-03T05:15Z	0.249	false
2020-04-03T05:00Z	0.249	false
2020-04-03T04:45Z	0.249	false
2020-04-03T04:30Z	0.25	false
2020-04-03T04:15Z	0.249	false
2020-04-03T04:00Z	0.249	false
2020-04-03T03:45Z	0.251	false
2020-04-03T03:30Z	0.246	false
2020-04-03T03:15Z	0.248	false
2020-04-03T03:00Z	0.244	false
2020-04-03T02:45Z	0.243	false
2020-04-03T02:30Z	0.246	false
2020-04-03T02:15Z	0.245	false
2020-04-03T02:00Z	0.245	false
2020-04-03T01:45Z	0.245	false
2020-04-03T01:30Z	0.244	false
2020-04-03T01:15Z	0.241	false
2020-04-03T01:00Z	0.243	false
2020-04-03T00:45Z	0.243	false
2020-04-03T00:30Z	0.248	false
2020-04-03T00:15Z	0.245	false
2020-04-03T00:00Z	0.246	false
2020-04-02T23:45Z	0.245	false
2020-04-02T23:30Z	0.243	false
2020-04-02T23:15Z	0.24	false
2020-04-02T23:00Z	0.242	false
2020-04-02T22:45Z	0.238	false
2020-04-02T22:30Z	0.239	false
2020-04-02T22:15Z	0.24	false
2020-04-02T22:00Z	0.238	false
2020-04-02T21:45Z	0.24	false
2020-04-02T21:30Z	0.239	false
2020-04-02T21:15Z	0.238	false
2020-04-02T21:00Z	0.239	false
2020-04-02T20:45Z	0.238	false
2020-04-02T20:30Z	0.238	false
2020-04-02T20:15Z	0.243	false
2020-04-02T20:00Z	0.238	false
2020-04-02T19:45Z	0.238	false
2020-04-02T19:30Z	0.235	false
2020-04-02T19:15Z	0.234	false
2020-04-02T19:00Z	0.232	false
2020-04-02T18:45Z	0.235	false
2020-04-02T18:30Z	0.232	false
2020-04-02T18:15Z	0.236	false
2020-04-02T18:00Z	0.234	false
2020-04-02T17:45Z	0.236	false
2020-04-02T17:30Z	0.239	false
2020-04-02T17:15Z	0.237	false
2020-04-02T17:00Z	0.233	false
2020-04-02T16:45Z	0.234	false
2020-04-02T16:30Z	0.236	false
2020-04-02T16:15Z	0.232	false
2020-04-02T16:00Z	0.232	false
2020-04-02T15:45Z	0.232	false
2020-04-02T15:30Z	0.232	false
2020-04-02T15:15Z	0.236	false
2020-04-02T15:00Z	0.232	false
2020-04-02T14:45Z	0.233	false
2020-04-02T14:30Z	0.232	false
2020-04-02T14:15Z	0.228	false
2020-04-02T14:00Z	0.231	false
2020-04-02T13:45Z	0.232	false
2020-04-02T13:30Z	0.236	false
2020-04-02T13:15Z	0.232	false
2020-04-02T13:00Z	0.228	false
2020-04-02T12:45Z	0.228	false
2020-04-02T12:30Z	0.225	false
2020-04-02T12:15Z	0.226	false
2020-04-02T12:00Z	0.229	false
2020-04-02T11:45Z	0.229	false
2020-04-02T11:30Z	0.227	false
2020-04-02T11:15Z	0.231	false
2020-04-02T11:00Z	0.229	false
2020-04-02T10:45Z	0.226	false
2020-04-02T10:30Z	0.227	false
2020-04-02T10:15Z	0.229	false
2020-04-02T10:00Z	0.228	false
2020-04-02T09:45Z	0.229	false
2020-04-02T09:30Z	0.231	false
2020-04-02T09:15Z	0.23	false
2020-04-02T09:00Z	0.233	false
2020-04-02T08:45Z	0.232	false
2020-04-02T08:30Z	0.237	false
2020-04-02T08:15Z	0.24	false
2020-04-02T08:00Z	0.24	false
2020-04-02T07:45Z	0.247	false
2020-04-02T07:30Z	0.248	false
2020-04-02T07:15Z	0.249	false
2020-04-02T07:00Z	0.25	false
2020-04-02T06:45Z	0.251	false
2020-04-02T06:30Z	0.251	false
2020-04-02T06:15Z	0.251	false
2020-04-02T06:00Z	0.25	false
2020-04-02T05:45Z	0.25	false
2020-04-02T05:30Z	0.252	false
2020-04-02T05:15Z	0.251	false
2020-04-02T05:00Z	0.247	false
2020-04-02T04:45Z	0.252	false
2020-04-02T04:30Z	0.249	false
2020-04-02T04:15Z	0.252	false
2020-04-02T04:00Z	0.253	false
2020-04-02T03:45Z	0.258	false
2020-04-02T03:30Z	0.257	false
2020-04-02T03:15Z	0.259	false
2020-04-02T03:00Z	0.256	false
2020-04-02T02:45Z	0.258	false
2020-04-02T02:30Z	0.256	false
2020-04-02T02:15Z	0.26	false
2020-04-02T02:00Z	0.257	false
2020-04-02T01:45Z	0.257	false
2020-04-02T01:30Z	0.258	false
2020-04-02T01:15Z	0.26	false
2020-04-02T01:00Z	0.257	false
2020-04-02T00:45Z	0.259	false
2020-04-02T00:30Z	0.256	false
2020-04-02T00:15Z	0.257	false
2020-04-02T00:00Z	0.256	false
2020-04-01T23:45Z	0.255	false
2020-04-01T23:30Z	0.251	false
2020-04-01T23:15Z	0.241	false
2020-04-01T23:00Z	0.243	false
2020-04-01T22:45Z	0.244	false
2020-04-01T22:30Z	0.245	false
2020-04-01T22:15Z	0.244	false
2020-04-01T22:00Z	0.246	false
2020-04-01T21:45Z	0.244	false
2020-04-01T21:30Z	0.246	false
2020-04-01T21:15Z	0.243	false
2020-04-01T21:00Z	0.246	false
2020-04-01T20:45Z	0.245	false
2020-04-01T20:30Z	0.246	false
2020-04-01T20:15Z	0.25	false
2020-04-01T20:00Z	0.244	false
2020-04-01T19:45Z	0.245	false
2020-04-01T19:30Z	0.243	false
2020-04-01T19:15Z	0.246	false
2020-04-01T19:00Z	0.248	false
2020-04-01T18:45Z	0.249	false
2020-04-01T18:30Z	0.25	false
2020-04-01T18:15Z	0.25	false
2020-04-01T18:00Z	0.252	false
2020-04-01T17:45Z	0.251	false
2020-04-01T17:30Z	0.249	false
2020-04-01T17:15Z	0.248	false
2020-04-01T17:00Z	0.251	false
2020-04-01T16:45Z	0.249	false
2020-04-01T16:30Z	0.249	false
2020-04-01T16:15Z	0.25	false
2020-04-01T16:00Z	0.25	false
2020-04-01T15:45Z	0.248	false
2020-04-01T15:30Z	0.25	false
2020-04-01T15:15Z	0.25	false
2020-04-01T15:00Z	0.251	false
2020-04-01T14:45Z	0.247	false
2020-04-01T14:30Z	0.252	false
2020-04-01T14:15Z	0.247	false
2020-04-01T14:00Z	0.249	false
2020-04-01T13:45Z	0.25	false
2020-04-01T13:30Z	0.25	false
2020-04-01T13:15Z	0.249	false
2020-04-01T13:00Z	0.247	false
2020-04-01T12:45Z	0.25	false
2020-04-01T12:30Z	0.245	false
2020-04-01T12:15Z	0.249	false
2020-04-01T12:00Z	0.248	false
2020-04-01T11:45Z	0.249	false
2020-04-01T11:30Z	0.246	false
2020-04-01T11:15Z	0.244	false
2020-04-01T11:00Z	0.244	false
2020-04-01T10:45Z	0.245	false
2020-04-01T10:30Z	0.246	false
2020-04-01T10:15Z	0.245	false
2020-04-01T10:00Z	0.246	false
2020-04-01T09:45Z	0.245	false
2020-04-01T09:30Z	0.245	false
2020-04-01T09:15Z	0.244	false
2020-04-01T09:00Z	0.245	false
2020-04-01T08:45Z	0.245	false
2020-04-01T08:30Z	0.243	false
2020-04-01T08:15Z	0.246	false
2020-04-01T08:00Z	0.244	false
2020-04-01T07:45Z	0.247	false
2020-04-01T07:30Z	0.247	false
2020-04-01T07:15Z	0.247	false
2020-04-01T07:00Z	0.247	false
2020-04-01T06:45Z	0.249	false
2020-04-01T06:30Z	0.251	false
2020-04-01T06:15Z	0.252	false
2020-04-01T06:00Z	0.251	false
2020-04-01T05:45Z	0.25	false
2020-04-01T05:30Z	0.25	false
2020-04-01T05:15Z	0.253	false
2020-04-01T05:00Z	0.254	false
2020-04-01T04:45Z	0.253	false
2020-04-01T04:30Z	0.253	false
2020-04-01T04:15Z	0.255	false
2020-04-01T04:00Z	0.256	false
2020-04-01T03:45Z	0.255	false
2020-04-01T03:30Z	0.254	false
2020-04-01T03:15Z	0.256	false
2020-04-01T03:00Z	0.254	false
2020-04-01T02:45Z	0.261	false
2020-04-01T02:30Z	0.261	false
2020-04-01T02:15Z	0.26	false
2020-04-01T02:00Z	0.257	false
2020-04-01T01:45Z	0.26	false
2020-04-01T01:30Z	0.258	false
2020-04-01T01:15Z	0.259	false
2020-04-01T01:00Z	0.259	false
2020-04-01T00:45Z	0.261	false
2020-04-01T00:30Z	0.26	false
2020-04-01T00:15Z	0.264	false
2020-04-01T00:00Z	0.26	false
2020-03-31T23:45Z	0.259	false
2020-03-31T23:30Z	0.259	false
2020-03-31T23:15Z	0.261	false
2020-03-31T23:00Z	0.26	false
2020-03-31T22:45Z	0.259	false
2020-03-31T22:30Z	0.262	false
2020-03-31T22:15Z	0.265	false
2020-03-31T22:00Z	0.261	false
2020-03-31T21:45Z	0.263	false
2020-03-31T21:30Z	0.261	false
2020-03-31T21:15Z	0.261	false
2020-03-31T21:00Z	0.26	false
2020-03-31T20:45Z	0.262	false
2020-03-31T20:30Z	0.263	false
2020-03-31T20:15Z	0.263	false
2020-03-31T20:00Z	0.266	false
2020-03-31T19:45Z	0.264	false
2020-03-31T19:30Z	0.261	false
2020-03-31T19:15Z	0.259	false
2020-03-31T19:00Z	0.258	false
2020-03-31T18:45Z	0.255	false
2020-03-31T18:30Z	0.255	false
2020-03-31T18:15Z	0.253	false
2020-03-31T18:00Z	0.255	false
2020-03-31T17:45Z	0.253	false
2020-03-31T17:30Z	0.254	false
2020-03-31T17:15Z	0.257	false
2020-03-31T17:00Z	0.257	false
2020-03-31T16:45Z	0.255	false
2020-03-31T16:30Z	0.256	false
2020-03-31T16:15Z	0.256	false
2020-03-31T16:00Z	0.253	false
2020-03-31T15:45Z	0.252	false
2020-03-31T15:30Z	0.249	false
2020-03-31T15:15Z	0.249	false
2020-03-31T15:00Z	0.251	false
2020-03-31T14:45Z	0.249	false
2020-03-31T14:30Z	0.248	false
2020-03-31T14:15Z	0.249	false
2020-03-31T14:00Z	0.247	false
2020-03-31T13:45Z	0.247	false
2020-03-31T13:30Z	0.247	false
2020-03-31T13:15Z	0.248	false
2020-03-31T13:00Z	0.247	false
2020-03-31T12:45Z	0.251	false
2020-03-31T12:30Z	0.249	false
2020-03-31T12:15Z	0.246	false
2020-03-31T12:00Z	0.245	false
2020-03-31T11:45Z	0.244	false
2020-03-31T11:30Z	0.243	false
2020-03-31T11:15Z	0.243	false
2020-03-31T11:00Z	0.244	false
2020-03-31T10:45Z	0.242	false
2020-03-31T10:30Z	0.241	false
2020-03-31T10:15Z	0.241	false
2020-03-31T10:00Z	0.238	false
2020-03-31T09:45Z	0.24	false
2020-03-31T09:30Z	0.236	false
2020-03-31T09:15Z	0.24	false
2020-03-31T09:00Z	0.239	false
2020-03-31T08:45Z	0.239	false
2020-03-31T08:30Z	0.24	false
2020-03-31T08:15Z	0.239	false
2020-03-31T08:00Z	0.239	false
2020-03-31T07:45Z	0.236	false
2020-03-31T07:30Z	0.237	false
2020-03-31T07:15Z	0.24	false
2020-03-31T07:00Z	0.234	false
2020-03-31T06:45Z	0.235	false
2020-03-31T06:30Z	0.234	false
2020-03-31T06:15Z	0.231	false
2020-03-31T06:00Z	0.235	false
2020-03-31T05:45Z	0.232	false
2020-03-31T05:30Z	0.232	false
2020-03-31T05:15Z	0.232	false
2020-03-31T05:00Z	0.229	false
2020-03-31T04:45Z	0.229	false
2020-03-31T04:30Z	0.229	false
2020-03-31T04:15Z	0.229	false
2020-03-31T04:00Z	0.226	false
2020-03-31T03:45Z	0.228	false
2020-03-31T03:30Z	0.224	false
2020-03-31T03:15Z	0.224	false
2020-03-31T03:00Z	0.221	false
2020-03-31T02:45Z	0.22	false
2020-03-31T02:30Z	0.22	false
2020-03-31T02:15Z	0.218	false
2020-03-31T02:00Z	0.215	false
2020-03-31T01:45Z	0.214	false
2020-03-31T01:30Z	0.213	false
2020-03-31T01:15Z	0.212	false
2020-03-31T01:00Z	0.209	false
2020-03-31T00:45Z	0.208	false
2020-03-31T00:30Z	0.206	false
2020-03-31T00:15Z	0.201	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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