About this spot
Stock up on supplies before heading out. Starting from Broadway Street in Boulder, travel west on Baseline Road toward the mountains. The road becomes Flagstaff Road with numerous hairpin turns through a burn area. Continue until reaching Lakeshore Drive, which transitions to unpaved surface and terminates at a parking area. From the lot, walk straight ahead or east to locate the trailhead, then descend to Gross Reservoir (sturdy footwear recommended). The water safety sign marks the jump location. You'll need a running start for a 35-40 foot jump into deep, cold water. Remove all trash when leaving. The reservoir experiences regular patrols, particularly on summer weekends when boats can be heard approaching. Enforcement has intensified significantly. Rangers now patrol daily—both via boat and on land using concealment tactics. Over 170 citations at $50 each were issued in the previous year, with fines increasing for repeat violations. Depth at the jump site measures 10 feet. The site has documented fatalities and serious injuries. Rangers will issue citations even to people who are wet, indicating enforcement occurs both during and after jumping activities. Violators face zero-tolerance consequences.