From the surface, Blue Hole is a modest-sized, circular pool of water, about 80 feet in diameter. The water temperature is about 62° F, with a variation of a few degrees throughout the year. Several millions of gallons of spring water flow through the pool, finally spilling out through a rapidly-flowing stream that is about 5 feet wide. The pool is located inside City Limits of Santa Rosa, close to area businesses. Facilities at the pool are a modern shower room with lavatory stalls and a simple, plywood dive shop. A convention hall was under construction in November 2008. Scuba divers are charged a fee to swim, but skin divers are admitted at no charge.