Lower Black Box

Lower Black Box

San Rafael Swell—North of I-70
What to Expect
2C III ACA Canyon Rating
  • This route may require some scrambling where handlines can be useful to some.
  • You can usually expect some water that has light to moderate current with easy water hazards.
  • Competent and smaller groups (4±) typically complete the route in 5–8 hours
Other Details
Skill Level:
Beginner with competent leadership, not advised solo unless done before
Seasons:
Summer, Fall
Rappels:
0–2 to 50 ft
Additional Gear:
50 ft webbing or rope for emergencies; lifejacket recommended for any weak swimmers; good walking stick for checking pool depth; good enclosed water footwear (no sandals)
Water:
Many people use an inflated inner tube to float through the deep-water sections
Flash Flood Risk:
Very High—no escape once in the river
Expected Time:
7–9 hours (4+ in the water—beware of hypothermia)
Distance:
1.85 miles approach to San Rafael River; 2.64 miles to entry point; 4.2 miles of strenuous hiking; 1.85 miles back to vehicle
Notes:
  • Water in the San Rafael Swell is heavily mineralized and works as a laxative, even after being filtered.
  • Carry 3 liters of drinking water per person
  • Best attempted in temperatures above 80º and clear skies
Nearby Routes:
Upper Black Box

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