The berm was worse up close than it had looked from the high gate.
The toe — the downstream base of the earthen structure — had already lost approximately thirty centimeters of compacted fill from its forward face. The timber planking that lined the base was partly exposed and partly undermined, two of the anchor stakes already pulled free by the water pressure and lying at awkward angles in the mud.
Thomas could hear the water moving through the structure. A low sucking sound, rhythmic, indicating internal water movement through the fill material. Piping, in engineering terms — the worst thing that could happen to an earthen dam or berm, because once internal channels of water movement established themselves in compacted fill, they widened progressively and catastrophically.
He had perhaps ninety minutes before the berm failed completely.
He positioned the first blank parallel to the toe face, one meter downstream of the berm base, which would create a secondary barrier for the water to press against rather than the fill directly. Then he ran back to Barnaby, reset the chain to the second blank, and said "go."
They fell into a rhythm.
Barnaby pulled each blank from the equipment yard and dragged it across the eighty meters of wet ground to the berm with a steady, unhurried power that did not vary between the first pull and the eighth. He did not slow on the wet sections.
He did not slip. His massive hooves, spreading under his weight with each step, distributed his eight-hundred kilograms across a surface area that kept him stable where a lighter animal or a wheeled vehicle would have struggled.
Thomas positioned each blank and prepared the next chain attachment while Barnaby was returning to the yard. The turnaround cycle — drag out, position, return, reattach — ran to approximately six minutes per blank once they had found their pace.
By nine forty-five they had positioned eight blanks along the berm toe in a staggered double-layer configuration, each blank locked against its neighbor by the pressure of the water behind the berm, which Thomas used as a passive clamping force rather than fighting against it.
The piping sound from inside the berm had not stopped. But it had not gotten louder.
Thomas drove a series of heavy iron stakes through the blanks into the berm face, using a sledgehammer swung in the rain and flashlight, securing the timber structure to the earth behind it. Barnaby stood at the chain's end four meters away, resting in place, his breath coming in long slow draws, steam rising from his coat in the cold rain air.
"Two more," Thomas said. "Then I think we've got it."
Barnaby pulled his head up from where he'd been resting it and turned back toward the equipment yard.
The rhythm they found on the timber drag runs was the rhythm of long practice — not the mechanical repetition of trained behavior, but the organic synchronization of two working partners who understood each other's capabilities and limitations.
Thomas set the chain attachment point to minimize side-load stress on Barnaby's collar. He learned on the second run that the optimal chain length was slightly shorter than standard, which reduced the lateral sway of the timber during the turn at the berm.
Barnaby learned on the third run that the ground at the berm approach was softer than the equipment yard surface, and adjusted his stride pattern — shorter steps, more vertical drive, less horizontal reach — to maintain traction without slipping.
They made no wasted movements. Thomas did not call directions unless a course correction was needed. Barnaby did not pause at the end of each run waiting for instruction. They had established the pattern: drag, position, return, reattach. The cycle ran on its own momentum.
By the sixth blank, Thomas's arms ached from the sledgehammer work and his boots were soaked through. By the eighth blank, his headlamp was dimming and he switched to his backup. Barnaby's coat was dark with rain and his breath came in long measured draws, but his stride had not shortened and his pull had not weakened.
Thomas had worked with heavy horses for twenty years before Barnaby. He had never worked with one that maintained consistent pull force across a sustained series of heavy loads in difficult conditions.
Most draft horses either wore down over a long working session or held back slightly in reserve. Barnaby worked at the same level from the first pull to the last, as if he had simply decided what level of effort the task required and was delivering it, no more and no less.