one big giant umbrella

These would be pillars that were placed strategically around cities prone to bad weather and floods. When it begins to rain giant umbrellas are released from within the pillars and connect together to form one giant shelter for the whole city. The shelters can be made to slant in certain directions in order to direct the flow of the water as it hits the shelter. The water that is collected from these huge umbrellas could be stored for future droughts, poured into the nearest river, or, depending on how big the umbrellas are could be poured into countries in desperate need of water. The pillars could have some kind of sensor that can sense water (I don’t know much about that kind of thing) but they could also be manually controlled so that if the city/country is in desperate need of rain the pillars can be told not to release the umbrellas. The pillars can also be told to release the umbrellas every other rain fall so that gardens are still able to be naturally watered and stuff.