Difficult Run above Fox Lake near Fairfax Water Level
Live river level, flow, historical records and forecast for Difficult Run above Fox Lake near Fairfax in VA, United States, built from official government gauge data.
- Location VA, United States
- Watershed middle potomac catoctin
- Primary gauge 01645704 (USGS)
About Difficult Run above Fox Lake near Fairfax
Difficult Run above Fox Lake near Fairfax is a river in the Middle Potomac-Catoctin watershed, Virginia.
What the record shows
The station record runs for more than 19 years, and the range on this reach is clear.
The highest reading in the file is 4.35 ft (1.33 m), set in April 2014. The lowest is 0.71 ft (0.22 m), set in September 2016. That spread matters for anyone watching a bank, crossing, or pump intake: this stream can move from a low late-summer stage to a much higher event level in the same record.
Seasonally, the usual high point is March at 1.15 ft (0.35 m), while the usual low point is September at 0.98 ft (0.3 m). The typical annual swing is 2 in (5.2 cm), so day-to-day changes are usually modest compared with the record extremes.
The watershed
The gauge drains 5.5 sq mi (14.2 km2) above the station. That is the area feeding this reading, not the whole named watershed.
For this part of Virginia, the seasonal pattern is the one to watch: winter and spring are the wetter stretch, and brief summer low flows are part of the record. For residents, that means the stream is most likely to press against banks and low crossings in the colder, wetter months, while late-summer water levels are more likely to sit near the low end of the station history.
Reading the hero number
The number on the page is today’s stage compared with the median for this calendar day in the USGS record. That is more useful than raw elevation because a stage of the same height can mean different things at different times of year.
With more than 19 years on record, the median gives a local baseline for this date: it shows whether the stream is running above or below its usual seasonal mark, not just how high the water is in absolute terms.
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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