The short answer for a Khaki Campbell in an emergency
Seven days of feed and water is the minimum store for a Khaki Campbell duck, and fourteen days suits a household that storms, flooding, or distance from suppliers could isolate. A Khaki Campbell is a small bird next to cattle or horses, so the quantities are modest: a laying duck eats a measured scoop of waterfowl or layer feed each day and drinks roughly a litre of water, often more in hot weather. The catch is not the volume but the form the water takes. A duck's drinking supply must be deep enough for her to submerge her bill and splash her head, because that is how she keeps her nostrils and eyes clean, so a store planned around a narrow bottle or shallow saucer under-serves her even when the total volume looks right.
Storing feed a laying Khaki Campbell can rely on
Store the exact feed the Khaki Campbell already eats, in a sealed, rodent-proof bin kept somewhere dry, because switching a laying duck to an unfamiliar feed mid-emergency adds loose droppings and a laying dip on top of the crisis. Measure the store honestly by weighing out her normal daily portion and multiplying, rather than trusting that a part-used sack looks like two weeks. Keep the bin's contents rotating: feed from the emergency bin during ordinary weeks and refill it with fresh stock, so the oldest feed is always eaten in calm times. If she free-ranges and picks up part of her diet from the garden, remember that an emergency may confine her to the pen, where stored feed suddenly has to cover the whole ration, greens and insects included.
The water half: depth, cleanliness, and reserve volume
A Khaki Campbell drinks, dips, and rinses in the same water, which means her supply fouls faster than a chicken's and needs changing more often in any emergency routine. Store drinking water in covered containers that keep out droppings, bedding, and algae growth, and plan the reserve around daily changes rather than a single fill that is expected to last the week. A duck shut in a pen during a storm also loses access to her usual bathing water, so include enough extra for a small bathing tub on the worst days if space allows, since bathing keeps feathers in condition and feathers in condition are her weatherproofing. Position containers where you can lift and tip them daily without hauling them across a flooded or frozen yard.
Checking the duck's store before it is ever needed
Walk the Khaki Campbell's store the way you would at the start of any disruption: open the feed bin and smell for damp or mould, tip out one container of stored water and refill it fresh, and confirm the pen's own drinker bucket is sound and crack-free. Replace stored water regularly rather than treating it as permanent, and note the date each container was filled on the container itself. Recheck the amounts whenever the flock changes, because a store built for one duck covers two ducks for half the days. If a neighbour or family member would do the duck round in your absence, leave them the daily feed measure and the water-change routine in writing, not just the key to the pen.
Making the Khaki Campbell plan hold together under pressure
The store works best as part of a small written routine: daily feed measure, daily water change, a spare drinker if the main bucket cracks, and somewhere dry and predator-proof the duck can be shut into if her usual run is damaged. Practise the pen-shut routine once in calm weather so she is not being chased into an unfamiliar space for the first time during a storm. Keep the plan where the household can find it without you talking them through it. KinsLe Care Teams turns that routine into assigned checks for the Khaki Campbell's store, each one timestamped when done, so whoever is home can see the water was changed and the feed bin checked without a chain of phone calls.