The Upper Diversion Chamber of High-Arch was an underground cave of giant stone granite stonework that shook with the deep, terrifying roar of an imprisoned river.
Carved directly into the limestone roots of the mountain, the chamber was eighty feet long and forty feet wide, its vaulted ceiling supported by six huge eight-sided pillars of dressed dark rock. The air was ice-cold, thick with freezing stone spray, and smelling of wet stone, crushed lime, and ancient machine grease. Through the open iron grates of the floor, Tomas Reed could see the black, churning mass of the Great Siphon—millions of cubic feet of clean alpine snowmelt tearing through the underground limestone caverns under twelve sea-weights of deep water pressure.
Rising along the eastern wall of the cave stood the massive machinery of the main headworks: four huge ten-foot bronze rack-and-pinion winches, anchored to twelve-foot granite foundation blocks by two-inch Swedish iron tie-rods.
Each winch governed a ten-foot-wide, twelve-foot-high bronze water gate that sealed the intake portal of the Grand Aqueduct of Saint Eleanor. But the winches were not free to turn. Through the spokes of the five-foot cast-iron hand-wheels ran double loops of one-inch case-hardened steel logging chain, secured with heavy High court box-padlocks lacquered in black pitch. Across the gear-teeth, thick iron dog-collars had been driven into the bronze racks. That kept the gates from lifting more than eighteen inches. Just enough to wet the water chute, while sixty thousand miners’ inches of pure mountain water was diverted through backup…
