River Thames at St Johns Lock Water Level
Live river level, flow, historical records and forecast for River Thames at St Johns Lock in England, United Kingdom, built from official government gauge data.
- Location England, United Kingdom
- Primary gauge ea-0701TH (Environment Agency)
About River Thames at St Johns Lock
River Thames at St Johns Lock is a gauged river in England.
Season by season
This reach sits in a temperate river regime, so the rhythm is familiar: higher water in the colder half of the year, lower water in late winter and spring, and a summer drawdown that leaves more room in the channel. The seasonal high lands in November at 0.1 m (0.33 ft), while the seasonal low comes in March at 0.06 m (0.2 ft). That gap is modest on the gauge, but it still matters for moorings, intakes, and shallow edges used by fish or by people working from the bank.
The station’s typical annual swing is 4.2 cm (1.7 in). For anyone watching a dock line, that is the day-to-day movement to expect in an average year: small in centimetres, but enough to matter where clearance is tight.
Records and rises
The record range is much wider than the seasonal pattern. The highest level on record is 5.39 m (17.68 ft) in December 2019. The lowest is -0.14 m (-0.45 ft) in March 2008. Those two points show the reach can move well beyond its usual band, so a fixed installation should be judged against the extremes, not only the seasonal average.
With 31 years on record, this station has enough history to show the difference between ordinary month-to-month movement and the larger rises that show up only once in a while. For users on the water, that means the record high is the better marker for what the river can demand from a dock, bank step, or low crossing.
Reading the hero number
The number shown on the page is most useful when read against the median for the same calendar day, not as a raw height on its own. A river can sit at a similar level on different dates but mean very different things in the seasonal cycle; the median keeps the comparison tied to this station’s own record.
This station is published by the Environment Agency. For this reach, the day’s reading against the calendar-day median is the clearest way to judge whether the river is running near its usual range or sitting above it for this time of year, especially with more than 31 years of local record behind it.
How this page is built
Readings come from official government gauges and are rolled into daily records: the daily mean, high and low for every day on record. Each calendar day gets its own baseline from the full history, so the level you see is compared against what this specific date usually looks like rather than an annual average.
How Nibi Metrics works · Water stories
Nibi Metrics - live water levels, flow, and forecasts for lakes and rivers across Canada, the US and the UK
Real-time water levels, forecasts, and alerts for lakes and rivers across Canada, the US and the UK. Built on official government data.
Nibi Metrics tracks more than 13,000 gauged lakes and rivers across Canada, the United States and the United Kingdom, reading directly from official federal monitoring networks: the Water Survey of Canada, the United States Geological Survey, Quebec's provincial hydrometric network, and the Environment Agency for England. Every number on the platform is measured, not modelled - taken from a government gauge on the water itself and compared against that location's own historical record for this exact date.
What you can see for any monitored lake or river
The level right now, in feet or metres, updated as the source agency publishes new readings - for many stations that is every five to fifteen minutes. How today compares to typical: every location carries its own typical-for-this-date band built from its historical record, so a reading is never just a number - it is above, below, or near what this water usually does on this calendar day. Which way it is moving: a measured RISING, FALLING, or STEADY verdict computed from the gauge's own recent readings, with the rate of change - the difference between a flood ending and one beginning. What comes next: level forecasts up to 72 hours ahead, driven by the gauge's recent behaviour, upstream water, and quantitative precipitation forecasts, alongside live radar, lightning, and weather for the surrounding region.
Alerts that watch the water for you
Set a threshold on any location - a level, a distance above typical, or a rate of climb - and Nibi emails or notifies you the moment the gauge crosses it. Cottagers use it for spring freshet, anglers for river conditions, marinas and municipalities for operations. The scanning runs around the clock against the same measured data shown on every page.
Where Nibi comes from
Nibi means water in Anishinaabemowin. The platform began at a family cottage on Lake Muskoka, Ontario, where the spring melt floods the shoreline most years and the only forecast was standing on the dock, looking, and guessing. It grew into an independent, member-funded platform run by Muskoka Research Inc. - no investors, no data resale, and a privacy policy shorter than most cookie banners. The core data is free for everyone, forever; paid plans add automation like multi-location alerts, deep history, and reports.
Coverage
Nibi spans the continent: every Canadian province and territory with active federal gauges - from Vancouver Island rivers to the Muskoka lakes, prairie reservoirs, and Quebec's hydrometric network - and the United States from Maine to the Texas Hill Country, the Ohio Valley, and the Pacific Northwest. Coverage grows where the water news is: when a basin floods, its gauges join the platform with their full historical records attached. Many stations report every five to fifteen minutes; most report at least hourly; every page states exactly when its gauge last spoke.
Free forever, funded by members
The core promise is simple: the water data is free, for everyone, forever. Live levels, maps, radar, and recent history never sit behind a paywall. Paid plans fund the platform by adding automation - multi-location alerts, decades of history, longer forecasts, and PDF reports - so the people who need more carry the cost for everyone who just needs to check the lake before driving up. There are no investors and no advertising deals shaping what the data says.
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How every number is computed - About the platform
