Potomac River at Point of Rocks Water Level
Live river level, flow, historical records and forecast for Potomac River at Point of Rocks in MD, United States, built from official government gauge data.
- Location MD, United States
- Watershed middle potomac catoctin
- Primary gauge 01638500 (USGS)
About Potomac River at Point of Rocks
The Potomac River at Point of Rocks sits in the Middle Potomac-Catoctin watershed, Maryland.
What the record shows
The station has more than 50 years of record. The highest reading in that span was 23.86 ft (7.27 m) in March 2010. The lowest was 0.72 ft (0.22 m) in September 2010.
That spread matters on the ground. A river that can move from a September low to a March flood asks a lot of docks, intakes, and bank access. The typical annual swing is 30.7 in (78 cm), and the seasonal pattern is clear: the usual high point comes in May at 3.89 ft (1.19 m), while the usual low point comes in September at 1.33 ft (0.41 m). In this part of the Mid-Atlantic, winter and spring rain floods are the main flood season, tropical remnants can deliver the biggest events, and summer low flows are common between storms.
The watershed
This gauge drains 9,651 sq mi (24,996 km2) above the station. That is the area feeding this reading, not the whole watershed mapped on a page.
For people living or fishing here, the upstream area is large enough that conditions can change after widespread rain, not just after local showers. The record and the seasonal cycle both point to a river that can run low in late summer and then rise sharply in the wetter season.
Reading the hero number
The hero number is today’s reading compared with the median for this calendar day across the station’s record. That is more useful than raw elevation because a stage can look high or low only in relation to what this river usually does on this date.
With more than 50 years on record, the USGS median gives a fair local baseline for the season and the day. It lets you see whether the river is running above its usual footing, below it, or near it right now.
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.
Water Stories
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How every number is computed - About the platform
