Robin Scheswohl captured this image inside the New Irvington Tunnel in the Sunol Valley. From her vantage point inside the Vargas East Tunnel section, Scheswohl pointed her camera west toward sunlight streaming down the Vargas Shaft—the brightly lit area in the background.
Scheswohl regularly photographs the more than 80 projects undertaken by San Francisco's Water System Improvement Program to upgrade the Hetch Hetchy Regional Water System. The New Irvington Tunnel will run 3.5 miles and have an internal diameter between 8.5 ft and 10.5 ft. Hole-through is expected this summer.