Water to horses: I've only prepared for floods, where pasturage or the animals themselves are at risk, and water sources are deemed to be compromised (floodwater is generally not safe for man nor animal to drink) - the answer to how to water your horses is to move them to safer ground. In the case of local evacuation plans that means to the county fairgrounds, where water is safe and plentiful, and if the flood is big enough, accommodations are made to house a lot of animals and their owners, if they need to be with them, which they generally do. If not the fairgrounds, other local land owners and live stock holders can agree on a safe pasturage site. This works in flood zones in King and Lewis counties.

Local responders and EM generally don't have the resources to take water trucks to fill n inflatable pools every day; better to move your animals to the water until the floodwaters subside and local water sources are restored.

Drought, wild fires and other water interruptions - these could have different answers than for floods, but generally you can still address the safety of your animals by temporary evacuation to a reliable water source.