Avoca Spring is a linear, elongated pool that continuously boils with built-up, solidified sinter above the water level. Some of the surrounding area with runoff water is home to orange-colored thermophiles. Avoca Spring has steady boiling and overflowing activity, but no defined eruptions. Earthquakes have a history of altering this continuous activity, with periods of dormancy, and seems to be directly related to Silver Globe Geyser activity.

Avoca Spring has an average temperate of 193.7°F (89.8°C), an average pH of 8.3, and an average conductivity of 2287 uS/cm.

Hot Springs

Hot springs are the most common hydrothermal features in Yellowstone. Their plumbing has no constrictions.

Superheated water cools as it reaches the surface, sinks, and is replaced by hotter water from below.

This circulation prevents water from reaching the temperature needed to set off an eruption.

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.