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

Check for flood warnings in this area

Latest recorded level 0.26m at 10:30pm Sunday 17 January 2021.

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
▼

• 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

You're missing out. A graph should be visible here.
Upgrade your browser to see and use all the features of this service.

You're missing out. A graph should be visible here.

Javascript must be enabled.

Observed data

DateTime	Value	Error
2021-01-17T22:30Z	0.259	false
2021-01-17T22:15Z	0.26	false
2021-01-17T22:00Z	0.26	false
2021-01-17T21:45Z	0.257	false
2021-01-17T21:30Z	0.261	false
2021-01-17T21:15Z	0.252	false
2021-01-17T21:00Z	0.254	false
2021-01-17T20:45Z	0.247	false
2021-01-17T20:30Z	0.224	false
2021-01-17T20:15Z	0.246	false
2021-01-17T20:00Z	0.241	false
2021-01-17T19:45Z	0.234	false
2021-01-17T19:30Z	0.248	false
2021-01-17T19:15Z	0.237	false
2021-01-17T19:00Z	0.254	false
2021-01-17T18:45Z	0.257	false
2021-01-17T18:30Z	0.248	false
2021-01-17T18:15Z	0.257	false
2021-01-17T18:00Z	0.267	false
2021-01-17T17:45Z	0.295	false
2021-01-17T17:30Z	0.292	false
2021-01-17T17:15Z	0.297	false
2021-01-17T17:00Z	0.276	false
2021-01-17T16:45Z	0.277	false
2021-01-17T16:30Z	0.278	false
2021-01-17T16:15Z	0.267	false
2021-01-17T16:00Z	0.267	false
2021-01-17T15:45Z	0.261	false
2021-01-17T15:30Z	0.266	false
2021-01-17T15:15Z	0.259	false
2021-01-17T15:00Z	0.263	false
2021-01-17T14:45Z	0.265	false
2021-01-17T14:30Z	0.261	false
2021-01-17T14:15Z	0.274	false
2021-01-17T14:00Z	0.274	false
2021-01-17T13:45Z	0.27	false
2021-01-17T13:30Z	0.271	false
2021-01-17T13:15Z	0.274	false
2021-01-17T13:00Z	0.247	false
2021-01-17T12:45Z	0.255	false
2021-01-17T12:30Z	0.248	false
2021-01-17T12:15Z	0.247	false
2021-01-17T12:00Z	0.251	false
2021-01-17T11:45Z	0.252	false
2021-01-17T11:30Z	0.247	false
2021-01-17T11:15Z	0.255	false
2021-01-17T11:00Z	0.256	false
2021-01-17T10:45Z	0.255	false
2021-01-17T10:30Z	0.265	false
2021-01-17T10:15Z	0.268	false
2021-01-17T10:00Z	0.281	false
2021-01-17T09:45Z	0.289	false
2021-01-17T09:30Z	0.282	false
2021-01-17T09:15Z	0.283	false
2021-01-17T09:00Z	0.283	false
2021-01-17T08:45Z	0.283	false
2021-01-17T08:30Z	0.288	false
2021-01-17T08:15Z	0.29	false
2021-01-17T08:00Z	0.29	false
2021-01-17T07:45Z	0.281	false
2021-01-17T07:30Z	0.293	false
2021-01-17T07:15Z	0.29	false
2021-01-17T07:00Z	0.284	false
2021-01-17T06:45Z	0.285	false
2021-01-17T06:30Z	0.288	false
2021-01-17T06:15Z	0.291	false
2021-01-17T06:00Z	0.287	false
2021-01-17T05:45Z	0.288	false
2021-01-17T05:30Z	0.293	false
2021-01-17T05:15Z	0.281	false
2021-01-17T05:00Z	0.284	false
2021-01-17T04:45Z	0.287	false
2021-01-17T04:30Z	0.287	false
2021-01-17T04:15Z	0.283	false
2021-01-17T04:00Z	0.289	false
2021-01-17T03:45Z	0.291	false
2021-01-17T03:30Z	0.283	false
2021-01-17T03:15Z	0.28	false
2021-01-17T03:00Z	0.283	false
2021-01-17T02:45Z	0.282	false
2021-01-17T02:30Z	0.283	false
2021-01-17T02:15Z	0.281	false
2021-01-17T02:00Z	0.283	false
2021-01-17T01:45Z	0.288	false
2021-01-17T01:30Z	0.279	false
2021-01-17T01:15Z	0.279	false
2021-01-17T01:00Z	0.283	false
2021-01-17T00:45Z	0.281	false
2021-01-17T00:30Z	0.275	false
2021-01-17T00:15Z	0.285	false
2021-01-17T00:00Z	0.28	false
2021-01-16T23:45Z	0.278	false
2021-01-16T23:30Z	0.276	false
2021-01-16T23:15Z	0.279	false
2021-01-16T23:00Z	0.276	false
2021-01-16T22:45Z	0.274	false
2021-01-16T22:30Z	0.274	false
2021-01-16T22:15Z	0.272	false
2021-01-16T22:00Z	0.273	false
2021-01-16T21:45Z	0.27	false
2021-01-16T21:30Z	0.275	false
2021-01-16T21:15Z	0.27	false
2021-01-16T21:00Z	0.271	false
2021-01-16T20:45Z	0.27	false
2021-01-16T20:30Z	0.273	false
2021-01-16T20:15Z	0.277	false
2021-01-16T20:00Z	0.27	false
2021-01-16T19:45Z	0.271	false
2021-01-16T19:30Z	0.274	false
2021-01-16T19:15Z	0.272	false
2021-01-16T19:00Z	0.272	false
2021-01-16T18:45Z	0.267	false
2021-01-16T18:30Z	0.272	false
2021-01-16T18:15Z	0.27	false
2021-01-16T18:00Z	0.27	false
2021-01-16T17:45Z	0.272	false
2021-01-16T17:30Z	0.264	false
2021-01-16T17:15Z	0.269	false
2021-01-16T17:00Z	0.264	false
2021-01-16T16:45Z	0.265	false
2021-01-16T16:30Z	0.26	false
2021-01-16T16:15Z	0.269	false
2021-01-16T16:00Z	0.258	false
2021-01-16T15:45Z	0.26	false
2021-01-16T15:30Z	0.258	false
2021-01-16T15:15Z	0.261	false
2021-01-16T15:00Z	0.256	false
2021-01-16T14:45Z	0.254	false
2021-01-16T14:30Z	0.247	false
2021-01-16T14:15Z	0.254	false
2021-01-16T14:00Z	0.256	false
2021-01-16T13:45Z	0.251	false
2021-01-16T13:30Z	0.25	false
2021-01-16T13:15Z	0.252	false
2021-01-16T13:00Z	0.252	false
2021-01-16T12:45Z	0.259	false
2021-01-16T12:30Z	0.255	false
2021-01-16T12:15Z	0.25	false
2021-01-16T12:00Z	0.248	false
2021-01-16T11:45Z	0.252	false
2021-01-16T11:30Z	0.253	false
2021-01-16T11:15Z	0.255	false
2021-01-16T11:00Z	0.256	false
2021-01-16T10:45Z	0.252	false
2021-01-16T10:30Z	0.252	false
2021-01-16T10:15Z	0.256	false
2021-01-16T10:00Z	0.25	false
2021-01-16T09:45Z	0.257	false
2021-01-16T09:30Z	0.247	false
2021-01-16T09:15Z	0.249	false
2021-01-16T09:00Z	0.257	false
2021-01-16T08:45Z	0.248	false
2021-01-16T08:30Z	0.254	false
2021-01-16T08:15Z	0.249	false
2021-01-16T08:00Z	0.254	false
2021-01-16T07:45Z	0.25	false
2021-01-16T07:30Z	0.243	false
2021-01-16T07:15Z	0.244	false
2021-01-16T07:00Z	0.253	false
2021-01-16T06:45Z	0.248	false
2021-01-16T06:30Z	0.253	false
2021-01-16T06:15Z	0.252	false
2021-01-16T06:00Z	0.25	false
2021-01-16T05:45Z	0.25	false
2021-01-16T05:30Z	0.25	false
2021-01-16T05:15Z	0.256	false
2021-01-16T05:00Z	0.253	false
2021-01-16T04:45Z	0.258	false
2021-01-16T04:30Z	0.256	false
2021-01-16T04:15Z	0.266	false
2021-01-16T04:00Z	0.256	false
2021-01-16T03:45Z	0.258	false
2021-01-16T03:30Z	0.261	false
2021-01-16T03:15Z	0.263	false
2021-01-16T03:00Z	0.265	false
2021-01-16T02:45Z	0.262	false
2021-01-16T02:30Z	0.265	false
2021-01-16T02:15Z	0.262	false
2021-01-16T02:00Z	0.264	false
2021-01-16T01:45Z	0.268	false
2021-01-16T01:30Z	0.269	false
2021-01-16T01:15Z	0.26	false
2021-01-16T01:00Z	0.264	false
2021-01-16T00:45Z	0.265	false
2021-01-16T00:30Z	0.256	false
2021-01-16T00:15Z	0.267	false
2021-01-16T00:00Z	0.262	false
2021-01-15T23:45Z	0.259	false
2021-01-15T23:30Z	0.257	false
2021-01-15T23:15Z	0.261	false
2021-01-15T23:00Z	0.263	false
2021-01-15T22:45Z	0.257	false
2021-01-15T22:30Z	0.255	false
2021-01-15T22:15Z	0.26	false
2021-01-15T22:00Z	0.255	false
2021-01-15T21:45Z	0.26	false
2021-01-15T21:30Z	0.251	false
2021-01-15T21:15Z	0.251	false
2021-01-15T21:00Z	0.246	false
2021-01-15T20:45Z	0.249	false
2021-01-15T20:30Z	0.253	false
2021-01-15T20:15Z	0.246	false
2021-01-15T20:00Z	0.247	false
2021-01-15T19:45Z	0.243	false
2021-01-15T19:30Z	0.245	false
2021-01-15T19:15Z	0.244	false
2021-01-15T19:00Z	0.243	false
2021-01-15T18:45Z	0.235	false
2021-01-15T18:30Z	0.234	false
2021-01-15T18:15Z	0.236	false
2021-01-15T18:00Z	0.232	false
2021-01-15T17:45Z	0.238	false
2021-01-15T17:30Z	0.23	false
2021-01-15T17:15Z	0.236	false
2021-01-15T17:00Z	0.232	false
2021-01-15T16:45Z	0.225	false
2021-01-15T16:30Z	0.226	false
2021-01-15T16:15Z	0.23	false
2021-01-15T16:00Z	0.229	false
2021-01-15T15:45Z	0.23	false
2021-01-15T15:30Z	0.223	false
2021-01-15T15:15Z	0.227	false
2021-01-15T15:00Z	0.226	false
2021-01-15T14:45Z	0.224	false
2021-01-15T14:30Z	0.222	false
2021-01-15T14:15Z	0.223	false
2021-01-15T14:00Z	0.227	false
2021-01-15T13:45Z	0.228	false
2021-01-15T13:30Z	0.227	false
2021-01-15T13:15Z	0.225	false
2021-01-15T13:00Z	0.225	false
2021-01-15T12:45Z	0.229	false
2021-01-15T12:30Z	0.228	false
2021-01-15T12:15Z	0.224	false
2021-01-15T12:00Z	0.224	false
2021-01-15T11:45Z	0.22	false
2021-01-15T11:30Z	0.218	false
2021-01-15T11:15Z	0.219	false
2021-01-15T11:00Z	0.217	false
2021-01-15T10:45Z	0.211	false
2021-01-15T10:30Z	0.206	false
2021-01-15T10:15Z	0.188	false
2021-01-15T10:00Z	0.197	false
2021-01-15T09:45Z	0.189	false
2021-01-15T09:30Z	0.194	false
2021-01-15T09:15Z	0.192	false
2021-01-15T09:00Z	0.194	false
2021-01-15T08:45Z	0.192	false
2021-01-15T08:30Z	0.201	false
2021-01-15T08:15Z	0.198	false
2021-01-15T08:00Z	0.198	false
2021-01-15T07:45Z	0.193	false
2021-01-15T07:30Z	0.195	false
2021-01-15T07:15Z	0.205	false
2021-01-15T07:00Z	0.205	false
2021-01-15T06:45Z	0.204	false
2021-01-15T06:30Z	0.201	false
2021-01-15T06:15Z	0.212	false
2021-01-15T06:00Z	0.212	false
2021-01-15T05:45Z	0.207	false
2021-01-15T05:30Z	0.212	false
2021-01-15T05:15Z	0.209	false
2021-01-15T05:00Z	0.21	false
2021-01-15T04:45Z	0.215	false
2021-01-15T04:30Z	0.211	false
2021-01-15T04:15Z	0.216	false
2021-01-15T04:00Z	0.214	false
2021-01-15T03:45Z	0.217	false
2021-01-15T03:30Z	0.218	false
2021-01-15T03:15Z	0.228	false
2021-01-15T03:00Z	0.226	false
2021-01-15T02:45Z	0.223	false
2021-01-15T02:30Z	0.227	false
2021-01-15T02:15Z	0.228	false
2021-01-15T02:00Z	0.237	false
2021-01-15T01:45Z	0.236	false
2021-01-15T01:30Z	0.236	false
2021-01-15T01:15Z	0.24	false
2021-01-15T01:00Z	0.236	false
2021-01-15T00:45Z	0.244	false
2021-01-15T00:30Z	0.245	false
2021-01-15T00:15Z	0.246	false
2021-01-15T00:00Z	0.248	false
2021-01-14T23:45Z	0.252	false
2021-01-14T23:30Z	0.257	false
2021-01-14T23:15Z	0.254	false
2021-01-14T23:00Z	0.256	false
2021-01-14T22:45Z	0.259	false
2021-01-14T22:30Z	0.262	false
2021-01-14T22:15Z	0.268	false
2021-01-14T22:00Z	0.265	false
2021-01-14T21:45Z	0.268	false
2021-01-14T21:30Z	0.269	false
2021-01-14T21:15Z	0.271	false
2021-01-14T21:00Z	0.271	false
2021-01-14T20:45Z	0.269	false
2021-01-14T20:30Z	0.273	false
2021-01-14T20:15Z	0.269	false
2021-01-14T20:00Z	0.271	false
2021-01-14T19:45Z	0.267	false
2021-01-14T19:30Z	0.268	false
2021-01-14T19:15Z	0.262	false
2021-01-14T19:00Z	0.262	false
2021-01-14T18:45Z	0.258	false
2021-01-14T18:30Z	0.257	false
2021-01-14T18:15Z	0.255	false
2021-01-14T18:00Z	0.252	false
2021-01-14T17:45Z	0.246	false
2021-01-14T17:30Z	0.23	false
2021-01-14T17:15Z	0.229	false
2021-01-14T17:00Z	0.233	false
2021-01-14T16:45Z	0.224	false
2021-01-14T16:30Z	0.229	false
2021-01-14T16:15Z	0.23	false
2021-01-14T16:00Z	0.215	false
2021-01-14T15:45Z	0.256	false
2021-01-14T15:30Z	0.254	false
2021-01-14T15:15Z	0.259	false
2021-01-14T15:00Z	0.259	false
2021-01-14T14:45Z	0.267	false
2021-01-14T14:30Z	0.297	false
2021-01-14T14:15Z	0.257	false
2021-01-14T14:00Z	0.225	false
2021-01-14T13:45Z	0.199	false
2021-01-14T13:30Z	0.195	false
2021-01-14T13:15Z	0.194	false
2021-01-14T13:00Z	0.192	false
2021-01-14T12:45Z	0.192	false
2021-01-14T12:30Z	0.184	false
2021-01-14T12:15Z	0.183	false
2021-01-14T12:00Z	0.18	false
2021-01-14T11:45Z	0.173	false
2021-01-14T11:30Z	0.166	false
2021-01-14T11:15Z	0.158	false
2021-01-14T11:00Z	0.152	false
2021-01-14T10:45Z	0.14	false
2021-01-14T10:30Z	0.109	false
2021-01-14T10:15Z	0.083	false
2021-01-14T10:00Z	0.109	false
2021-01-14T09:45Z	0.098	false
2021-01-14T09:30Z	0.099	false
2021-01-14T09:15Z	0.097	false
2021-01-14T09:00Z	0.098	false
2021-01-14T08:45Z	0.107	false
2021-01-14T08:30Z	0.102	false
2021-01-14T08:15Z	0.108	false
2021-01-14T08:00Z	0.12	false
2021-01-14T07:45Z	0.128	false
2021-01-14T07:30Z	0.137	false
2021-01-14T07:15Z	0.135	false
2021-01-14T07:00Z	0.137	false
2021-01-14T06:45Z	0.134	false
2021-01-14T06:30Z	0.141	false
2021-01-14T06:15Z	0.133	false
2021-01-14T06:00Z	0.132	false
2021-01-14T05:45Z	0.13	false
2021-01-14T05:30Z	0.134	false
2021-01-14T05:15Z	0.137	false
2021-01-14T05:00Z	0.13	false
2021-01-14T04:45Z	0.13	false
2021-01-14T04:30Z	0.134	false
2021-01-14T04:15Z	0.134	false
2021-01-14T04:00Z	0.131	false
2021-01-14T03:45Z	0.13	false
2021-01-14T03:30Z	0.139	false
2021-01-14T03:15Z	0.133	false
2021-01-14T03:00Z	0.141	false
2021-01-14T02:45Z	0.134	false
2021-01-14T02:30Z	0.136	false
2021-01-14T02:15Z	0.137	false
2021-01-14T02:00Z	0.146	false
2021-01-14T01:45Z	0.138	false
2021-01-14T01:30Z	0.14	false
2021-01-14T01:15Z	0.139	false
2021-01-14T01:00Z	0.145	false
2021-01-14T00:45Z	0.141	false
2021-01-14T00:30Z	0.149	false
2021-01-14T00:15Z	0.144	false
2021-01-14T00:00Z	0.141	false
2021-01-13T23:45Z	0.146	false
2021-01-13T23:30Z	0.15	false
2021-01-13T23:15Z	0.153	false
2021-01-13T23:00Z	0.152	false
2021-01-13T22:45Z	0.153	false
2021-01-13T22:30Z	0.157	false
2021-01-13T22:15Z	0.152	false
2021-01-13T22:00Z	0.158	false
2021-01-13T21:45Z	0.164	false
2021-01-13T21:30Z	0.165	false
2021-01-13T21:15Z	0.168	false
2021-01-13T21:00Z	0.161	false
2021-01-13T20:45Z	0.168	false
2021-01-13T20:30Z	0.171	false
2021-01-13T20:15Z	0.168	false
2021-01-13T20:00Z	0.174	false
2021-01-13T19:45Z	0.171	false
2021-01-13T19:30Z	0.177	false
2021-01-13T19:15Z	0.18	false
2021-01-13T19:00Z	0.181	false
2021-01-13T18:45Z	0.183	false
2021-01-13T18:30Z	0.183	false
2021-01-13T18:15Z	0.178	false
2021-01-13T18:00Z	0.178	false
2021-01-13T17:45Z	0.183	false
2021-01-13T17:30Z	0.181	false
2021-01-13T17:15Z	0.183	false
2021-01-13T17:00Z	0.189	false
2021-01-13T16:45Z	0.199	false
2021-01-13T16:30Z	0.207	false
2021-01-13T16:15Z	0.228	false
2021-01-13T16:00Z	0.238	false
2021-01-13T15:45Z	0.241	false
2021-01-13T15:30Z	0.243	false
2021-01-13T15:15Z	0.239	false
2021-01-13T15:00Z	0.236	false
2021-01-13T14:45Z	0.242	false
2021-01-13T14:30Z	0.24	false
2021-01-13T14:15Z	0.235	false
2021-01-13T14:00Z	0.239	false
2021-01-13T13:45Z	0.239	false
2021-01-13T13:30Z	0.237	false
2021-01-13T13:15Z	0.235	false
2021-01-13T13:00Z	0.24	false
2021-01-13T12:45Z	0.239	false
2021-01-13T12:30Z	0.238	false
2021-01-13T12:15Z	0.235	false
2021-01-13T12:00Z	0.235	false
2021-01-13T11:45Z	0.232	false
2021-01-13T11:30Z	0.243	false
2021-01-13T11:15Z	0.237	false
2021-01-13T11:00Z	0.231	false
2021-01-13T10:45Z	0.235	false
2021-01-13T10:30Z	0.237	false
2021-01-13T10:15Z	0.236	false
2021-01-13T10:00Z	0.233	false
2021-01-13T09:45Z	0.241	false
2021-01-13T09:30Z	0.238	false
2021-01-13T09:15Z	0.231	false
2021-01-13T09:00Z	0.234	false
2021-01-13T08:45Z	0.238	false
2021-01-13T08:30Z	0.234	false
2021-01-13T08:15Z	0.237	false
2021-01-13T08:00Z	0.24	false
2021-01-13T07:45Z	0.234	false
2021-01-13T07:30Z	0.236	false
2021-01-13T07:15Z	0.238	false
2021-01-13T07:00Z	0.239	false
2021-01-13T06:45Z	0.237	false
2021-01-13T06:30Z	0.237	false
2021-01-13T06:15Z	0.235	false
2021-01-13T06:00Z	0.232	false
2021-01-13T05:45Z	0.234	false
2021-01-13T05:30Z	0.239	false
2021-01-13T05:15Z	0.234	false
2021-01-13T05:00Z	0.236	false
2021-01-13T04:45Z	0.236	false
2021-01-13T04:30Z	0.236	false
2021-01-13T04:15Z	0.233	false
2021-01-13T04:00Z	0.237	false
2021-01-13T03:45Z	0.237	false
2021-01-13T03:30Z	0.234	false
2021-01-13T03:15Z	0.243	false
2021-01-13T03:00Z	0.234	false
2021-01-13T02:45Z	0.234	false
2021-01-13T02:30Z	0.235	false
2021-01-13T02:15Z	0.237	false
2021-01-13T02:00Z	0.236	false
2021-01-13T01:45Z	0.234	false
2021-01-13T01:30Z	0.238	false
2021-01-13T01:15Z	0.239	false
2021-01-13T01:00Z	0.236	false
2021-01-13T00:45Z	0.24	false
2021-01-13T00:30Z	0.24	false
2021-01-13T00:15Z	0.236	false
2021-01-13T00:00Z	0.237	false
2021-01-12T23:45Z	0.24	false
2021-01-12T23:30Z	0.24	false
2021-01-12T23:15Z	0.241	false
2021-01-12T23:00Z	0.241	false
2021-01-12T22:45Z	0.238	false
2021-01-12T22:30Z	0.238	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
• Check the long term flood risk for an area in England.

Share this page

• Twitter
• Facebook
• Email