Flood channels are built in Las Vegas to control and redirect sudden, heavy rainfall, which is a major threat due to the city's desert environment and position in a valley. The Las Vegas Valley acts like a bowl, so water from surrounding mountains collects rapidly, and the hard, non-absorbent ground means the water has nowhere to go but into flash floods that can cause billions of dollars in damage. The extensive network of concrete channels, tunnels, and detention basins channels this water awa

'What a storm': Las Vegas hit with fresh flash floods as rain pours into casino