January 23, 2026 – Yosemite National Park officials offer a glimpse back to the historic flooding of 1997. 

In January 1997, the Merced River became a raging torrent as an unusual storm pushed warm, moist air inland from the Pacific Ocean. Over a week, rainfall totals surpassed 20 inches, with rain falling as high as 9,200 feet elevation. Rapid runoff of this intense rain over a large area of the park, with a small contribution from melting snow at lower elevations of the park, caused the Merced River to swell to a record-setting crest of 14 feet above flood stage (24,600 cubic feet per second). This is the highest river flow ever measured since records started over 100 years ago.

The flood washed out roads and bridges in Yosemite Valley. More than 2,000 visitors and employees were temporarily stranded. Half of Yosemite’s 900 campsites were flooded, as well as guest rooms and employee cabins at the Yosemite Lodge. Yosemite Valley was closed to the public for over two months while the extensive infrastructure damage was repaired and replaced.

Although the flood negatively affected human infrastructure in Yosemite Valley, flooding is a natural process essential to the functioning of many ecosystems. Flood waters deliver organic matter and vital nutrients to the surrounding floodplain and improve wildlife habitat.

Next time you are in Yosemite Valley, look around and imagine how flood waters have changed the landscape that you see!

Note: See top number below of the 1997 flood level.

Photo credit: Sierra Sun Times

Photo credit: Sierra Sun Times

Video Description: Various footage of flooding in Yosemite Valley. Thousands of gallons of water tumble from waterfalls thousands of feet up in the air. The torrential current of a swollen river engulfs roads, bridges, and infrastructure. Once green meadows become lakes. Through it all, park staff attempts to travel in massive trucks to assess and mitigate damage.

View video here.

Source: NPS