North end of GBRA Calhoun Canal near Long Mott Water Level
Live river level, flow, historical records and forecast for North end of GBRA Calhoun Canal near Long Mott in TX, United States, built from official government gauge data.
- Location TX, United States
- Watershed east san antonio bay
- Primary gauge 08188590 (USGS)
About North end of GBRA Calhoun Canal near Long Mott
The North end of GBRA Calhoun Canal near Long Mott sits in the East San Antonio Bay watershed in Texas.
The watershed
This gauge sits on a canal reach in the East San Antonio Bay watershed. For people watching water levels here, the main signal is not a slow seasonal arc but short, rainfall-driven jumps, with long low stretches between events. That fits flash-flood country: the water can change in hours, so a dock, crossing, or intake can go from steady to stressed fast.
What the numbers say
The record high is 17.05 ft (5.2 m), set in March 2026. The record low is 7.3 ft (2.23 m), set in May 2021. That span tells you the range this station has already seen in only more than 10 years of record.
The seasonal pattern is tighter than those extremes. The highest typical month is August at 13.99 ft (4.26 m), and the lowest typical month is April at 13.32 ft (4.06 m). The typical annual swing is 8.1 in (20.6 cm). For someone keeping a boat, pump, or shoreline setup here, that means the usual year-to-year movement is modest, but the recorded highs and lows are still far enough apart to matter.
No fastest 24-hour rise is listed in the facts, so I’m not adding one.
Reading the hero number
The number shown at the top of the page is today’s reading compared with the median for this calendar day across the station record. That is the better way to read this site, because the same absolute level can mean something different in August than in April.
This station is measured by the USGS, and its record covers more than 10 years.
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
Field notes and explainers from the Nibi desk - how to read a staff gauge, what a 100-year flood actually means, how snowpack becomes summer water.
For five years, spring 2019 was the mark every Lake Muskoka decision answered to. In April 2026 the lake went two centimeters higher - and the official books have not caught up yet.
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
