HBP is a thermal spring with a maximum surface temperature of about 90°C. One of the earliest published descriptions of this thermal spring was made by G.A. Waring (1915) based on his observations made in 1908. Waring refers to the spring as Casa Diablo Hot Pool, however the spring is now more commonly referred to as Hot Bubbling Pool by local residents. Waring described the spring as a pool measuring about 30 by 35 yards with surface temperatures ranging between 120°F and 180°F (49°C and 82°C) and having no surface flow out but having a well defined outlet channel. This description fits within the range of conditions observed since 1982.

HBP lies in a shallow topographic depression between two northwest trending faults that are splays of the Hilton Creek Fault, one of several eastern Sierra frontal faults. The rock outcrop that forms a low cliff on the north side of the pool is composed of silicified sandstone that blankets a large area to the north and east of this site. The sandstone formed by cementation of sand and gravel that was deposited in a delaic environment along the shore of a Pleistocene lake that lapped against outcrops of Early Rhyolite composing the resurgent dome.

Systematic monitoring of pool stage by USGS began in 1989, prior to that time pool stage and water temperature were recorded for short periods lasting from a few days to several months. In recent years gage height or pool stage has been measured by a pressure transducer and recorded every 30 minutes on an electronic datalogger. These data are retrieved when the site is visited (approximately monthly) for calibration measurements. Gas and water chemistry data also have been collected on several occasions.

The size of the pool and surface temperatures have varied over time in response to climatic variables (air temperature, humidity, barometric pressure, and precipitation) as well as aquifer pressure changes resulting from variations in ground-water recharge and geothermal well pumping at Casa Diablo about 3 miles to the west. Pool stage increased by about 1.5 ft in July 1986 because of above average ground-water recharge resulting from winter precipitation amounting to about 150 percent of the long-term average at Mammoth Lakes. The large increase in pool volume caused the water temperature to decrease by about 5 °C. Geothermal well pumping at Casa Diablo increased by about 300 percent in December 1990; within days of the increased pumping, the stage of the pool began to drop and by mid-1992 had dropped by about 3.5 feet. More recently (2006), geothermal pumping at Casa Diablo was decreased by about 30 percent when new wells 3 miles farther to the west were activated (the overall rate of pumping, however, is similar to the long-term rate for 1992-2006). Pool stage at HBP began to rise within days of the change in the location of pumping and by late 2006 the stage had increased by about 4 feet, and continues to rise. Additionally, the color of the pool is becoming greener, particularly at the margins, due to algae that can only survive at temperatures below about 70°C, indicating a general cooling of the pool as has occurred previously with large increases in pool volume. Pool stage is also known to change in response to some local and distant earthquakes.

When the pool stage is low, boiling temperature springs and travertine terrace deposits are exposed along the shoreline. The water level in nearby well CW-3 (just 300 ft east of HBP) is affected by seasonal precipitation, atmospheric pressure, geothermal pumping, and seismic events. The changes in water level in CW3 closely match the changes in stage at HBP.