I don't get it. They call them resevoirs but don't have 4 walls. Besides a resevoir is an artificial lake. These are more like flood control planes or flood protection. I wonder why did they just build them in that area of town. Does it flood there often? Kingwood always floods and they need it. They are built by an actual resevoir. My god, wouldn't it be a disaster if the Lake Houston Dam broke. New Orleans had poor planning. When the levees break it basically becomes one big resevoir.