How about very focused and fast (high energy) water cannons, from the ground and from helicopters, as one among many anti-drone weapons? EDIT: A drone-clearing

How about very focused and fast (high energy) water cannons, from the ground and from helicopters, as one among many anti-drone weapons? EDIT: A drone-clearing drone, carrying the water cannon. It would be sent into an airspace where a problem drone has been reported, and either water down the offending drones, or report that they're gone. After clearing the airspace, firefighting aircraft are allowed in.