River Conditions
Illustrated map of Lake Tahoe

River stage

Happy Isles, Merced River

River level
0.59 ft
Status
Below flood stage
7-day change
+0.00 ft
Recent high
3.86 ft
Recent low
0.58 ft

Last reported 2026-10-13 | NWS HPIC1

30-day change
-0.18 ft
Average
1.53 ft
Readings
121
Data span
122 days
Record crest
13.27 ft

In brief

The Merced River at Happy Isles, CA read 0.59 ft on Oct 13, 2026, 6.91 ft below minor flood stage. That is 0.18 ft lower than 30 days earlier.

Source: National Weather Service gauge HPIC1

Water 50 °F (10 °C) · 2 °F warmer than normal for this date · -2 °F in 24 hours

River level timeline

0.00.40.71.01.3SEP 13SEP 18SEP 23SEP 28OCT 03OCT 08OCT 13HIGH 0.77LOW 0.580.59 ftLAST READING

Stage threshold profile

Minor flooding 7.50 ftModerate flooding 10.00 ftMajor flooding 13.27 ft CURRENT 0.59 ft

Highest crests on record

RankCrestDate
1 13.27 ft 1997-01-02
2 12.73 ft 1955-12-23

Flood crests recorded at this gauge by the National Weather Service.

What happens at each level

  1. 7.00 ft

    North Pines and Lower Pines campgrounds begin flooding.

  2. 7.50 ft

    Flood Stage. Housekeeping camp and Yosemite Valley backpacker campground begin to flood.

  3. 8.20 ft

    Swinging Bridge overtops. Water on road at Northside Drive, Southsie Drive, El Capitan crossover, and Sentinel crossover.

  4. 10.00 ft

    Northside Drive at Wosky Pond, Southside Drive at Chapel Meadow, El Capitan crossover, and Sentinel crossover are impassable to vehicles.

  5. 13.27 ft

    Flood of Record: 1/2/97. $178 million in damage to Yosemite Valley.

Written by the local National Weather Service forecast office for this exact gauge.

Frequently asked questions

Is the Merced River flooding at Happy Isles?

No. The Merced River at Happy Isles is at 0.59 ft, 6.91 ft below minor flood stage.

What is the flood stage at Happy Isles?

The National Weather Service sets minor flooding 7.5 ft, moderate flooding 10 ft and major flooding 13.27 ft.

What is the highest the Merced River has been at Happy Isles?

The highest crest on record is 13.27 ft, on 1997-01-02.

Is the Merced River high or low right now at Happy Isles?

At 0.59 ft it is higher than 5% of readings over the last 122 days.

How warm is the water at Happy Isles, Merced River?

The water temperature at Happy Isles, Merced River is 50 °F (9.7 °C), measured 6:30 pm by USGS, which is 2 °F warmer than normal for this date over the past ten years. It has fallen 2.3 °F in the last 24 hours.

Stage and flood information from the NOAA National Weather Service (gauge HPIC1); daily history from the U.S. Geological Survey (site 11264500). Last reading 2026-10-13. For flood safety decisions always follow official National Weather Service warnings.