California · La Grange, CA
Tuolumne River float season
Gauge 11289650 on the La Grange Dam to Basso Bridge on the lower Tuolumne. A cold, clear Gold Country tailwater where summer tubes and fall drift boats share water below the old La Grange diversion.
Right now at this gauge
loading CFS
Checking the live gauge…
Well above typical for this date
Live reading from the USGS gauge page for Tuolumne River. Provisional data — subject to revision.
The year on this river
In a typical year at the La Grange gauge, the Tuolumne River runs fullest Feb–Apr and leanest Jul–Sep. Where today's reading falls inside that rhythm matters more than the raw number — the same flow that feels thin in spring can be the summer norm. Half of all past April days at this gauge ran above 599 CFS; the August median is 100 CFS.
| Month | Typical flow (CFS) | Relative volume |
|---|---|---|
| January | 334 | |
| February | 359 | |
| March | 362 | |
| April | 599 | |
| May | 306 | |
| June | 113 | |
| July | 108 | |
| August | 100 | |
| September | 105 | |
| October | 307 | |
| November | 252 | |
| December | 289 |
Record context
This gauge has measured daily flow since 1971 — 55 years of record. The largest daily average ever logged here was 50,100 CFS, in January 1997. Rivers do that sometimes; it's why the safety panel above isn't decoration.
Planning dates? The trip-window checker shows what flows have historically looked like on any week you pick for this river, or see what a CFS actually looks like.
More California float rivers
-
American River
Lower American, Sunrise Avenue to River Bend through Sacramento
Fullest: May–Jul
-
Cache Creek
Cache Creek canyon from Rumsey through Camp Haswell
Fullest: May–Jul
-
Klamath River
Mid-Klamath canyon around Seiad Valley and Happy Camp
Fullest: Feb–Apr
-
Merced River
Yosemite Valley bridges and the El Portal canyon below Redbud
Fullest: Apr–Jun
-
North Fork American River
Chamberlain Falls canyon above Lake Clementine
Fullest: Mar–May
-
Russian River
Forestville to Guerneville past Johnson's Beach
Fullest: Jan–Mar
Common questions
When is the Tuolumne River usually at its fullest?
At the La Grange gauge, the fullest stretch of a typical year is Feb–Apr, with the single highest monthly median in April (about 599 CFS). The leanest months are usually Jul–Sep.
What is a typical summer flow on the Tuolumne River?
The July median at this gauge is about 108 CFS — half of past Julys ran higher, half lower. Late summer is this river's lean season, so expect readings to drift down as the season goes on.
Is the Tuolumne River safe to float right now?
No flow number can answer that, and this site never labels a river safe. What the data can tell you is how today's reading compares with 55 years of this date's history — well above typical means pushier, colder, faster water. Pair that context with a PFD, a look at the river from the bank, and a call to a local outfitter before you commit.
Which USGS gauge does this page use?
USGS gauge 11289650 (TUOLUMNE R BL LAGRANGE DAM NR LAGRANGE CA), chosen because it best represents the La Grange Dam to Basso Bridge on the lower Tuolumne. Daily records here reach back to 1971.
Data: USGS gauge 11289650, approved daily records 1971–2026, retrieved 2026-08-07. Live readings are provisional and subject to revision. U.S. Geological Survey data is public domain.