Flash Spring is a geyser with an average temperate of 195.9°F (91.1°C), an average pH of 8.1, and an average conductivity of 1400 uS/cm. Flash Spring exhibits steady activity in a superheated, fan-shaped pool with a runoff channel. There is a large sinter perimeter around the pool, with rocks at the north end. Flash Spring is set in the hillside and bubbles occasionally from the center vent.

Geysers

Geysers have constrictions in their plumbing systems that prevent water from moving freely to the surface where heat would escape. Water beneath the constrictions creates a buildup of steam. Eventually the steam pushes water past the constrictions and the geyser erupts.

Use Caution in Hydrothermal Areas

• Stay on boardwalks and designated trails.
• Hydrothermal water can severely burn you.
• Never run, push, or shove.
• Supervise children at all times.
• Do not scratch hydrothermal mats.

You are responsible for your safety.

Think safety, act safely. Yellowstone is a dangerous place.