River level River Thames at Marsh Lock (upstream data)

Check for flood warnings in this area

Latest recorded level 0.25m at 9:00pm Tuesday 20 April 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
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• Measured level
• When the water level reaches 0.40m 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
2021-04-20T20:00Z	0.251	false
2021-04-20T19:45Z	0.253	false
2021-04-20T19:30Z	0.252	false
2021-04-20T19:15Z	0.253	false
2021-04-20T19:00Z	0.252	false
2021-04-20T18:45Z	0.254	false
2021-04-20T18:30Z	0.253	false
2021-04-20T18:15Z	0.253	false
2021-04-20T18:00Z	0.252	false
2021-04-20T17:45Z	0.253	false
2021-04-20T17:30Z	0.254	false
2021-04-20T17:15Z	0.253	false
2021-04-20T17:00Z	0.253	false
2021-04-20T16:45Z	0.249	false
2021-04-20T16:30Z	0.245	false
2021-04-20T16:15Z	0.243	false
2021-04-20T16:00Z	0.241	false
2021-04-20T15:45Z	0.237	false
2021-04-20T15:30Z	0.235	false
2021-04-20T15:15Z	0.233	false
2021-04-20T15:00Z	0.231	false
2021-04-20T14:45Z	0.231	false
2021-04-20T14:30Z	0.234	false
2021-04-20T14:15Z	0.232	false
2021-04-20T14:00Z	0.236	false
2021-04-20T13:45Z	0.234	false
2021-04-20T13:30Z	0.239	false
2021-04-20T13:15Z	0.241	false
2021-04-20T13:00Z	0.24	false
2021-04-20T12:45Z	0.239	false
2021-04-20T12:30Z	0.241	false
2021-04-20T12:15Z	0.24	false
2021-04-20T12:00Z	0.242	false
2021-04-20T11:45Z	0.239	false
2021-04-20T11:30Z	0.243	false
2021-04-20T11:15Z	0.239	false
2021-04-20T11:00Z	0.239	false
2021-04-20T10:45Z	0.239	false
2021-04-20T10:30Z	0.239	false
2021-04-20T10:15Z	0.24	false
2021-04-20T10:00Z	0.239	false
2021-04-20T09:45Z	0.241	false
2021-04-20T09:30Z	0.237	false
2021-04-20T09:15Z	0.24	false
2021-04-20T09:00Z	0.241	false
2021-04-20T08:45Z	0.242	false
2021-04-20T08:30Z	0.243	false
2021-04-20T08:15Z	0.242	false
2021-04-20T08:00Z	0.24	false
2021-04-20T07:45Z	0.24	false
2021-04-20T07:30Z	0.24	false
2021-04-20T07:15Z	0.239	false
2021-04-20T07:00Z	0.239	false
2021-04-20T06:45Z	0.238	false
2021-04-20T06:30Z	0.24	false
2021-04-20T06:15Z	0.239	false
2021-04-20T06:00Z	0.24	false
2021-04-20T05:45Z	0.239	false
2021-04-20T05:30Z	0.239	false
2021-04-20T05:15Z	0.239	false
2021-04-20T05:00Z	0.24	false
2021-04-20T04:45Z	0.24	false
2021-04-20T04:30Z	0.24	false
2021-04-20T04:15Z	0.24	false
2021-04-20T04:00Z	0.24	false
2021-04-20T03:45Z	0.24	false
2021-04-20T03:30Z	0.24	false
2021-04-20T03:15Z	0.241	false
2021-04-20T03:00Z	0.242	false
2021-04-20T02:45Z	0.24	false
2021-04-20T02:30Z	0.241	false
2021-04-20T02:15Z	0.242	false
2021-04-20T02:00Z	0.242	false
2021-04-20T01:45Z	0.242	false
2021-04-20T01:30Z	0.242	false
2021-04-20T01:15Z	0.243	false
2021-04-20T01:00Z	0.242	false
2021-04-20T00:45Z	0.242	false
2021-04-20T00:30Z	0.242	false
2021-04-20T00:15Z	0.242	false
2021-04-20T00:00Z	0.243	false
2021-04-19T23:45Z	0.243	false
2021-04-19T23:30Z	0.244	false
2021-04-19T23:15Z	0.244	false
2021-04-19T23:00Z	0.242	false
2021-04-19T22:45Z	0.244	false
2021-04-19T22:30Z	0.243	false
2021-04-19T22:15Z	0.244	false
2021-04-19T22:00Z	0.243	false
2021-04-19T21:45Z	0.244	false
2021-04-19T21:30Z	0.245	false
2021-04-19T21:15Z	0.244	false
2021-04-19T21:00Z	0.243	false
2021-04-19T20:45Z	0.244	false
2021-04-19T20:30Z	0.244	false
2021-04-19T20:15Z	0.245	false
2021-04-19T20:00Z	0.244	false
2021-04-19T19:45Z	0.244	false
2021-04-19T19:30Z	0.243	false
2021-04-19T19:15Z	0.242	false
2021-04-19T19:00Z	0.242	false
2021-04-19T18:45Z	0.243	false
2021-04-19T18:30Z	0.244	false
2021-04-19T18:15Z	0.243	false
2021-04-19T18:00Z	0.246	false
2021-04-19T17:45Z	0.244	false
2021-04-19T17:30Z	0.245	false
2021-04-19T17:15Z	0.246	false
2021-04-19T17:00Z	0.244	false
2021-04-19T16:45Z	0.245	false
2021-04-19T16:30Z	0.243	false
2021-04-19T16:15Z	0.242	false
2021-04-19T16:00Z	0.245	false
2021-04-19T15:45Z	0.239	false
2021-04-19T15:30Z	0.243	false
2021-04-19T15:15Z	0.247	false
2021-04-19T15:00Z	0.239	false
2021-04-19T14:45Z	0.242	false
2021-04-19T14:30Z	0.244	false
2021-04-19T14:15Z	0.245	false
2021-04-19T14:00Z	0.244	false
2021-04-19T13:45Z	0.242	false
2021-04-19T13:30Z	0.241	false
2021-04-19T13:15Z	0.243	false
2021-04-19T13:00Z	0.243	false
2021-04-19T12:45Z	0.242	false
2021-04-19T12:30Z	0.246	false
2021-04-19T12:15Z	0.238	false
2021-04-19T12:00Z	0.241	false
2021-04-19T11:45Z	0.241	false
2021-04-19T11:30Z	0.242	false
2021-04-19T11:15Z	0.243	false
2021-04-19T11:00Z	0.224	false
2021-04-19T10:45Z	0.239	false
2021-04-19T10:30Z	0.241	false
2021-04-19T10:15Z	0.244	false
2021-04-19T10:00Z	0.241	false
2021-04-19T09:45Z	0.239	false
2021-04-19T09:30Z	0.239	false
2021-04-19T09:15Z	0.239	false
2021-04-19T09:00Z	0.237	false
2021-04-19T08:45Z	0.239	false
2021-04-19T08:30Z	0.238	false
2021-04-19T08:15Z	0.237	false
2021-04-19T08:00Z	0.237	false
2021-04-19T07:45Z	0.237	false
2021-04-19T07:30Z	0.236	false
2021-04-19T07:15Z	0.236	false
2021-04-19T07:00Z	0.234	false
2021-04-19T06:45Z	0.236	false
2021-04-19T06:30Z	0.233	false
2021-04-19T06:15Z	0.234	false
2021-04-19T06:00Z	0.235	false
2021-04-19T05:45Z	0.234	false
2021-04-19T05:30Z	0.235	false
2021-04-19T05:15Z	0.234	false
2021-04-19T05:00Z	0.233	false
2021-04-19T04:45Z	0.234	false
2021-04-19T04:30Z	0.233	false
2021-04-19T04:15Z	0.234	false
2021-04-19T04:00Z	0.233	false
2021-04-19T03:45Z	0.232	false
2021-04-19T03:30Z	0.233	false
2021-04-19T03:15Z	0.233	false
2021-04-19T03:00Z	0.232	false
2021-04-19T02:45Z	0.233	false
2021-04-19T02:30Z	0.233	false
2021-04-19T02:15Z	0.234	false
2021-04-19T02:00Z	0.233	false
2021-04-19T01:45Z	0.233	false
2021-04-19T01:30Z	0.233	false
2021-04-19T01:15Z	0.233	false
2021-04-19T01:00Z	0.232	false
2021-04-19T00:45Z	0.232	false
2021-04-19T00:30Z	0.232	false
2021-04-19T00:15Z	0.232	false
2021-04-19T00:00Z	0.232	false
2021-04-18T23:45Z	0.233	false
2021-04-18T23:30Z	0.234	false
2021-04-18T23:15Z	0.231	false
2021-04-18T23:00Z	0.233	false
2021-04-18T22:45Z	0.232	false
2021-04-18T22:30Z	0.232	false
2021-04-18T22:15Z	0.232	false
2021-04-18T22:00Z	0.232	false
2021-04-18T21:45Z	0.232	false
2021-04-18T21:30Z	0.233	false
2021-04-18T21:15Z	0.232	false
2021-04-18T21:00Z	0.233	false
2021-04-18T20:45Z	0.233	false
2021-04-18T20:30Z	0.233	false
2021-04-18T20:15Z	0.234	false
2021-04-18T20:00Z	0.235	false
2021-04-18T19:45Z	0.234	false
2021-04-18T19:30Z	0.235	false
2021-04-18T19:15Z	0.235	false
2021-04-18T19:00Z	0.234	false
2021-04-18T18:45Z	0.235	false
2021-04-18T18:30Z	0.233	false
2021-04-18T18:15Z	0.232	false
2021-04-18T18:00Z	0.232	false
2021-04-18T17:45Z	0.234	false
2021-04-18T17:30Z	0.235	false
2021-04-18T17:15Z	0.235	false
2021-04-18T17:00Z	0.232	false
2021-04-18T16:45Z	0.23	false
2021-04-18T16:30Z	0.233	false
2021-04-18T16:15Z	0.231	false
2021-04-18T16:00Z	0.216	false
2021-04-18T15:45Z	0.22	false
2021-04-18T15:30Z	0.232	false
2021-04-18T15:15Z	0.233	false
2021-04-18T15:00Z	0.221	false
2021-04-18T14:45Z	0.228	false
2021-04-18T14:30Z	0.226	false
2021-04-18T14:15Z	0.228	false
2021-04-18T14:00Z	0.22	false
2021-04-18T13:45Z	0.233	false
2021-04-18T13:30Z	0.232	false
2021-04-18T13:15Z	0.225	false
2021-04-18T13:00Z	0.229	false
2021-04-18T12:45Z	0.231	false
2021-04-18T12:30Z	0.225	false
2021-04-18T12:15Z	0.227	false
2021-04-18T12:00Z	0.227	false
2021-04-18T11:45Z	0.223	false
2021-04-18T11:30Z	0.228	false
2021-04-18T11:15Z	0.223	false
2021-04-18T11:00Z	0.229	false
2021-04-18T10:45Z	0.227	false
2021-04-18T10:30Z	0.22	false
2021-04-18T10:15Z	0.217	false
2021-04-18T10:00Z	0.221	false
2021-04-18T09:45Z	0.226	false
2021-04-18T09:30Z	0.224	false
2021-04-18T09:15Z	0.221	false
2021-04-18T09:00Z	0.225	false
2021-04-18T08:45Z	0.205	false
2021-04-18T08:30Z	0.222	false
2021-04-18T08:15Z	0.225	false
2021-04-18T08:00Z	0.223	false
2021-04-18T07:45Z	0.224	false
2021-04-18T07:30Z	0.223	false
2021-04-18T07:15Z	0.223	false
2021-04-18T07:00Z	0.224	false
2021-04-18T06:45Z	0.224	false
2021-04-18T06:30Z	0.224	false
2021-04-18T06:15Z	0.224	false
2021-04-18T06:00Z	0.223	false
2021-04-18T05:45Z	0.223	false
2021-04-18T05:30Z	0.223	false
2021-04-18T05:15Z	0.224	false
2021-04-18T05:00Z	0.223	false
2021-04-18T04:45Z	0.225	false
2021-04-18T04:30Z	0.225	false
2021-04-18T04:15Z	0.225	false
2021-04-18T04:00Z	0.225	false
2021-04-18T03:45Z	0.225	false
2021-04-18T03:30Z	0.226	false
2021-04-18T03:15Z	0.226	false
2021-04-18T03:00Z	0.227	false
2021-04-18T02:45Z	0.227	false
2021-04-18T02:30Z	0.227	false
2021-04-18T02:15Z	0.227	false
2021-04-18T02:00Z	0.228	false
2021-04-18T01:45Z	0.229	false
2021-04-18T01:30Z	0.228	false
2021-04-18T01:15Z	0.23	false
2021-04-18T01:00Z	0.23	false
2021-04-18T00:45Z	0.23	false
2021-04-18T00:30Z	0.23	false
2021-04-18T00:15Z	0.231	false
2021-04-18T00:00Z	0.231	false
2021-04-17T23:45Z	0.231	false
2021-04-17T23:30Z	0.232	false
2021-04-17T23:15Z	0.233	false
2021-04-17T23:00Z	0.232	false
2021-04-17T22:45Z	0.233	false
2021-04-17T22:30Z	0.234	false
2021-04-17T22:15Z	0.234	false
2021-04-17T22:00Z	0.233	false
2021-04-17T21:45Z	0.235	false
2021-04-17T21:30Z	0.234	false
2021-04-17T21:15Z	0.235	false
2021-04-17T21:00Z	0.235	false
2021-04-17T20:45Z	0.235	false
2021-04-17T20:30Z	0.235	false
2021-04-17T20:15Z	0.236	false
2021-04-17T20:00Z	0.236	false
2021-04-17T19:45Z	0.236	false
2021-04-17T19:30Z	0.236	false
2021-04-17T19:15Z	0.238	false
2021-04-17T19:00Z	0.24	false
2021-04-17T18:45Z	0.241	false
2021-04-17T18:30Z	0.238	false
2021-04-17T18:15Z	0.238	false
2021-04-17T18:00Z	0.24	false
2021-04-17T17:45Z	0.241	false
2021-04-17T17:30Z	0.241	false
2021-04-17T17:15Z	0.241	false
2021-04-17T17:00Z	0.239	false
2021-04-17T16:45Z	0.239	false
2021-04-17T16:30Z	0.238	false
2021-04-17T16:15Z	0.238	false
2021-04-17T16:00Z	0.236	false
2021-04-17T15:45Z	0.238	false
2021-04-17T15:30Z	0.236	false
2021-04-17T15:15Z	0.234	false
2021-04-17T15:00Z	0.237	false
2021-04-17T14:45Z	0.234	false
2021-04-17T14:30Z	0.237	false
2021-04-17T14:15Z	0.238	false
2021-04-17T14:00Z	0.239	false
2021-04-17T13:45Z	0.238	false
2021-04-17T13:30Z	0.238	false
2021-04-17T13:15Z	0.239	false
2021-04-17T13:00Z	0.235	false
2021-04-17T12:45Z	0.236	false
2021-04-17T12:30Z	0.237	false
2021-04-17T12:15Z	0.234	false
2021-04-17T12:00Z	0.233	false
2021-04-17T11:45Z	0.236	false
2021-04-17T11:30Z	0.233	false
2021-04-17T11:15Z	0.232	false
2021-04-17T11:00Z	0.233	false
2021-04-17T10:45Z	0.237	false
2021-04-17T10:30Z	0.227	false
2021-04-17T10:15Z	0.231	false
2021-04-17T10:00Z	0.229	false
2021-04-17T09:45Z	0.226	false
2021-04-17T09:30Z	0.23	false
2021-04-17T09:15Z	0.231	false
2021-04-17T09:00Z	0.215	false
2021-04-17T08:45Z	0.235	false
2021-04-17T08:30Z	0.236	false
2021-04-17T08:15Z	0.237	false
2021-04-17T08:00Z	0.235	false
2021-04-17T07:45Z	0.235	false
2021-04-17T07:30Z	0.235	false
2021-04-17T07:15Z	0.237	false
2021-04-17T07:00Z	0.237	false
2021-04-17T06:45Z	0.236	false
2021-04-17T06:30Z	0.236	false
2021-04-17T06:15Z	0.237	false
2021-04-17T06:00Z	0.236	false
2021-04-17T05:45Z	0.237	false
2021-04-17T05:30Z	0.238	false
2021-04-17T05:15Z	0.238	false
2021-04-17T05:00Z	0.238	false
2021-04-17T04:45Z	0.238	false
2021-04-17T04:30Z	0.239	false
2021-04-17T04:15Z	0.239	false
2021-04-17T04:00Z	0.239	false
2021-04-17T03:45Z	0.239	false
2021-04-17T03:30Z	0.237	false
2021-04-17T03:15Z	0.238	false
2021-04-17T03:00Z	0.239	false
2021-04-17T02:45Z	0.239	false
2021-04-17T02:30Z	0.239	false
2021-04-17T02:15Z	0.239	false
2021-04-17T02:00Z	0.239	false
2021-04-17T01:45Z	0.238	false
2021-04-17T01:30Z	0.238	false
2021-04-17T01:15Z	0.239	false
2021-04-17T01:00Z	0.239	false
2021-04-17T00:45Z	0.239	false
2021-04-17T00:30Z	0.238	false
2021-04-17T00:15Z	0.238	false
2021-04-17T00:00Z	0.239	false
2021-04-16T23:45Z	0.238	false
2021-04-16T23:30Z	0.238	false
2021-04-16T23:15Z	0.239	false
2021-04-16T23:00Z	0.238	false
2021-04-16T22:45Z	0.238	false
2021-04-16T22:30Z	0.238	false
2021-04-16T22:15Z	0.238	false
2021-04-16T22:00Z	0.239	false
2021-04-16T21:45Z	0.238	false
2021-04-16T21:30Z	0.239	false
2021-04-16T21:15Z	0.238	false
2021-04-16T21:00Z	0.238	false
2021-04-16T20:45Z	0.241	false
2021-04-16T20:30Z	0.239	false
2021-04-16T20:15Z	0.239	false
2021-04-16T20:00Z	0.239	false
2021-04-16T19:45Z	0.239	false
2021-04-16T19:30Z	0.238	false
2021-04-16T19:15Z	0.239	false
2021-04-16T19:00Z	0.239	false
2021-04-16T18:45Z	0.24	false
2021-04-16T18:30Z	0.242	false
2021-04-16T18:15Z	0.24	false
2021-04-16T18:00Z	0.241	false
2021-04-16T17:45Z	0.24	false
2021-04-16T17:30Z	0.241	false
2021-04-16T17:15Z	0.24	false
2021-04-16T17:00Z	0.239	false
2021-04-16T16:45Z	0.242	false
2021-04-16T16:30Z	0.241	false
2021-04-16T16:15Z	0.228	false
2021-04-16T16:00Z	0.241	false
2021-04-16T15:45Z	0.24	false
2021-04-16T15:30Z	0.24	false
2021-04-16T15:15Z	0.238	false
2021-04-16T15:00Z	0.243	false
2021-04-16T14:45Z	0.242	false
2021-04-16T14:30Z	0.241	false
2021-04-16T14:15Z	0.246	false
2021-04-16T14:00Z	0.24	false
2021-04-16T13:45Z	0.241	false
2021-04-16T13:30Z	0.243	false
2021-04-16T13:15Z	0.245	false
2021-04-16T13:00Z	0.243	false
2021-04-16T12:45Z	0.245	false
2021-04-16T12:30Z	0.245	false
2021-04-16T12:15Z	0.246	false
2021-04-16T12:00Z	0.244	false
2021-04-16T11:45Z	0.243	false
2021-04-16T11:30Z	0.243	false
2021-04-16T11:15Z	0.248	false
2021-04-16T11:00Z	0.243	false
2021-04-16T10:45Z	0.244	false
2021-04-16T10:30Z	0.24	false
2021-04-16T10:15Z	0.241	false
2021-04-16T10:00Z	0.248	false
2021-04-16T09:45Z	0.249	false
2021-04-16T09:30Z	0.248	false
2021-04-16T09:15Z	0.248	false
2021-04-16T09:00Z	0.247	false
2021-04-16T08:45Z	0.246	false
2021-04-16T08:30Z	0.246	false
2021-04-16T08:15Z	0.247	false
2021-04-16T08:00Z	0.245	false
2021-04-16T07:45Z	0.245	false
2021-04-16T07:30Z	0.247	false
2021-04-16T07:15Z	0.246	false
2021-04-16T07:00Z	0.246	false
2021-04-16T06:45Z	0.247	false
2021-04-16T06:30Z	0.248	false
2021-04-16T06:15Z	0.246	false
2021-04-16T06:00Z	0.247	false
2021-04-16T05:45Z	0.247	false
2021-04-16T05:30Z	0.247	false
2021-04-16T05:15Z	0.248	false
2021-04-16T05:00Z	0.248	false
2021-04-16T04:45Z	0.248	false
2021-04-16T04:30Z	0.248	false
2021-04-16T04:15Z	0.248	false
2021-04-16T04:00Z	0.249	false
2021-04-16T03:45Z	0.249	false
2021-04-16T03:30Z	0.249	false
2021-04-16T03:15Z	0.25	false
2021-04-16T03:00Z	0.25	false
2021-04-16T02:45Z	0.249	false
2021-04-16T02:30Z	0.25	false
2021-04-16T02:15Z	0.251	false
2021-04-16T02:00Z	0.25	false
2021-04-16T01:45Z	0.25	false
2021-04-16T01:30Z	0.25	false
2021-04-16T01:15Z	0.25	false
2021-04-16T01:00Z	0.25	false
2021-04-16T00:45Z	0.251	false
2021-04-16T00:30Z	0.251	false
2021-04-16T00:15Z	0.252	false
2021-04-16T00:00Z	0.252	false
2021-04-15T23:45Z	0.252	false
2021-04-15T23:30Z	0.251	false
2021-04-15T23:15Z	0.251	false
2021-04-15T23:00Z	0.252	false
2021-04-15T22:45Z	0.252	false
2021-04-15T22:30Z	0.253	false
2021-04-15T22:15Z	0.253	false
2021-04-15T22:00Z	0.252	false
2021-04-15T21:45Z	0.252	false
2021-04-15T21:30Z	0.253	false
2021-04-15T21:15Z	0.254	false
2021-04-15T21:00Z	0.253	false
2021-04-15T20:45Z	0.253	false
2021-04-15T20:30Z	0.253	false
2021-04-15T20:15Z	0.253	false

Forecast data

Key information

• Station name: Marsh Lock (upstream)
• Station ID: 7155
• River name: River Thames
• Typical range: 0.11m to 0.40m
• Highest level on record: 1.63m on 01 November 2001
• Site datum: 31.97mAOD (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.

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