Prompton Reservoir at Prompton Water Level
Live lake level, flow, historical records and forecast for Prompton Reservoir at Prompton in PA, United States, built from official government gauge data.
- Location PA, United States
- Watershed lackawaxen
- Primary gauge 01428900 (USGS)
About Prompton Reservoir at Prompton
Prompton Reservoir is in the Lackawaxen watershed in Pennsylvania.
The watershed
The reservoir’s gauge drains 59.6 sq mi (154 km2) upstream of this station. That is the area that feeds the reading here, not the whole watershed map label.
For people who watch this water, the main seasonal pattern is modest but clear. The typical high month is March at 1125.78 ft (343.14 m), and the typical low month is September at 1123.73 ft (342.51 m). The usual swing between those months is 24.6 in (62.5 cm). That is the range a dock, pump intake, or shoreline setup has to live with through the year.
What the numbers say
The record high is 1133.29 ft (345.43 m) in April 2022. The record low is 2.99 ft (0.91 m) in August 1988. Those two ends show how far the reservoir has moved over the record, and they are the sort of numbers that matter when you are checking access, shore exposure, or how much water is sitting in reserve.
This station has 40 years on record. That is enough history to separate a one-day bump from the usual seasonal shape. For this reservoir, spring is where the higher water tends to show up, while late summer is where the lower water tends to settle.
Reading the hero number
The hero number on this page is today’s reading compared with the median for this calendar day across the station record. That is more useful than raw elevation alone because it tells you whether the reservoir is running high or low for this date, not just what the staff gauge reads.
This is a USGS station, and the comparison is built from 40 years of record.
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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Inside the freshet cycle that puts Manitoba shorelines at risk each year - and why 2026 broke the script.
The science of snow water equivalent and why it drives the season ahead.
What the numbers on the measuring stick actually tell you.
Why Central and South Texas rivers go from gravel beds to fifty-year records in an afternoon - including July 2026 on the Nueces.
One percent, every year, forever - unwrapping hydrology's most misunderstood phrase, and how it differs from our own percentiles.
How every number is computed - About the platform
