How the River Cam is flowing compared with normal for the time of year — a live Environment Agency signal of how dry things are getting, with Cambridge Water's hosepipe-ban status alongside.
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From Town Tools. For the current version, visit https://www.town.tools/cambridge-england-gb/river-cam-drought
How much water is moving down the River Cam — measured just upstream of the city — set against what's normal for the time of year. It's a plain signal of how dry things are getting. Cambridge sits in the driest corner of Britain and draws almost all its tap water from the same chalk that feeds the river, so a low Cam and a stretched supply are the same story. The official word on the hosepipe ban comes from Cambridge Water, linked below.
Cam · Dernford, on the Cam a few miles south of the city near Sawston
0.19 m³/s
The Cam is very low for the time of year. Falling over the past couple of weeks. Daily mean for Saturday 11 July.
Around the 2nd percentile of July flows on record. That is about 46% of the normal July flow.
0.19 m³/s
Flow now
latest daily-mean discharge
0.29 m³/s – 0.59 m³/s
Typical for the month
the usual middle range in July (25th–75th percentile)
0.42 m³/s
Normal for the month
the long-term median July flow
The official word
This page describes the river day to day. The official drought status and any hosepipe ban are decided elsewhere — check here:
Why the Cam runs low in summer — and why it matters
The Cam is a chalk river. In a dry summer it naturally drops to a fraction of its winter flow, and the chalk aquifer that keeps it going is the same source about 97% of Cambridge's drinking water comes from. That makes this one of the least water-secure cities in the country: when the river is low, the aquifer behind it is under strain too. The proposed Fens Reservoir is years away, so for now the pressure is real every dry summer.
What this does and doesn't tell you
This page shows how the river is flowing day to day, compared with its own long-term record for the month. It is not a drought declaration and not a decision about water restrictions. The official drought status is set by the Environment Agency, and any hosepipe ban is Cambridge Water's call — both are linked below. A low reading here is a sign of a dry spell, not a forecast of one.
Updated . River data from the Environment Agency Hydrology API, under the Open Government Licence v3.0. Daily means may be revised.