The stabilization of the aquaculture vats had saved the food supply, but it had permanently increased the barony's hydraulic overhead. Between the new trickle-towers, the cooling jackets for the high-output kilns, and the constant thirst of the steam pistons, Ashfall was consuming water faster than the subterranean wells could replenish. The water table was dropping—a silent, invisible depletion that threatened to ground the entire industrial machine. To survive, Kael had to execute his most ambitious civil engineering project yet: the redirection and elevation of the River Ash.
The "grit" of the aqueduct project was the sheer volume of material required. The River Ash ran through a gorge nearly three hundred yards away and forty feet below the level of the main village. To bring that water to the barony, Kael couldn't just dig a ditch; he had to build a sustained-gradient bridge that could withstand the freezing frontier winters without cracking.
Kael designed a Modular Siphon-Aqueduct. Instead of a traditional Roman-style stone archway, which would take years to build, he utilized the surplus of refractory bricks and the new "Ashfall Standard" iron piping. The structure would consist of a series of brick piers supporting a heavy iron trough, insulated with a layer of packed ash and charcoal to prevent the water from freezing in transit.
"We aren't just moving water; we're moving energy," Kael told the assembly of laborers. He divided the six hundred souls into three shifts. "If the river stops flowing, the steam stops pushing. If the steam stops, the forges go cold. Every brick you lay is a minute of heat for your families."
The construction of the Intake Weir at the river's edge was the most dangerous phase. Rylen and the Tier 0 crews had to work in the freezing, fast-moving current, driving iron-shod timber piles into the rocky riverbed to create a diversion dam. The "grit" was literal: the silt from the riverbed scoured their skin, and the constant spray turned their clothing into suits of ice.
Kael implemented the Pneumatic Caisson. He designed a large, bottomless iron box that was lowered into the river. By pumping air into the box using a steam-driven bellows, the water was pushed out, allowing a small crew of three men to work on the dry riverbed to bolt the intake valves directly into the bedrock. It was a terrifying, claustrophobic environment; the men worked in a high-pressure pocket of air, knowing that a single mechanical failure in the bellows would result in instant drowning.
Socially, the aqueduct project became a symbol of the "Total Integrated State." The children of the barony were tasked with mixing the waterproof mortar—a specialized blend of lime, volcanic ash, and crushed brick. The elderly managed the "Insulation Line," packing the charcoal layers around the iron pipes. For the first time, every single demographic of Ashfall was working on a single, visible structure that connected the wild river to their industrial heart.
A technical failure occurred at the halfway mark. The calculated gradient of the aqueduct—a precise drop of two inches for every hundred feet—was compromised by a localized subsidence in the soil. The water didn't flow; it pooled and began to exert lateral pressure that threatened to topple the brick piers.
Kael didn't tear down the piers. He engineered a Hydraulic Ram. By utilizing the kinetic energy of the river's own flow at the intake, he created a pump that used water-hammer pressure to "push" the water up the slight incline caused by the subsidence. It was an elegant, self-powering solution that turned a geological error into a mechanical feature.
As the sluice gates groaned open, a massive volume of water surged into the iron trough. The sound was a deep, resonant roar that echoed through the valley. The water traveled the three hundred yards, crossing the bridge of iron and brick, and finally poured into the central reservoir of Ashfall.
The "Water Debt" was paid. The trickle-towers roared with new life, and the steam pistons finally had a reliable, high-volume source of coolant. Kael stood at the reservoir, the spray of the river cooling his soot-stained face. He had successfully harnessed the primary artery of the landscape.
"The river belongs to us now, Elms," Kael said, watching the water churn. "But the Duke's sulfur plant is downstream. By taking this water, we've just given them a reason to walk up the riverbank to see who cut off their supply. Start the Defensive Moat construction. If we have the water, we might as well use it as a wall."