A four-hundred-pound water-pressure head was enough to cut through wood and strip flesh from bone.
The boiling water spraying from the grout port in Ring Forty-Eight was not just a flood hazard. It was an existential threat to the tunnel. If the heat underground water bed eroded the fractured dark rock surrounding the concrete rings, the high-pressure water would wash out the loose ground base, collapsing the entire two-hundred-and-fifty-foot lined bore into a waterlogged sinkhole.
“Shut off the spark power bars,” Giles shouted into the sound horn, his voice slicing through the roar of rushing water.
“Switch emergency lighting to isolated battery lanterns. Nobody steps in the invert water until the copper lines are dead.”
Apprentice linemen scrambled along the narrow high walkways, throwing the master knife switches.
The hissing arc-lamps flickered out, replaced instantly by the warm, yellow glow of sealed storage tank lanterns strung from the ceiling bolts.
Aldous Swift-Current, the town water engineer who had spent three seasons designing Haven-Hold’s canal networks, splashed through the steaming ankle-deep flood wearing heavy hardened rubber overalls. Behind him, four dwarven pipefitters dragged a heavy two-inch braided steel injection lance fitted with a quarter-turn bronze ball-cock valve.
“Deep water pressure is four hundred and twenty pounds, Lord Giles,” Aldous reported. He wiped scalding water drops from his leather goggles. “The fissure is fed by an underground heat lake beneath the dark rock doorstep.
