"...Receding floodwater would naturally have followed the cracks and fractures in the freshly deposited and uplifted Flood sediments of the Colorado Plateau. The water draining off the Colorado Plateau would have flowed westerly toward the Pacific Ocean. Rapid uplift and surface drainage of receding floodwater provide both the path and the necessary volume of water to quickly carve out Grand Canyon. And this process would have concluded prior to the Ice Age, eliminating any timing conflicts with the canyon formation and the later lava flows originating on the Uinkaret Plateau. No hypothetical lakes are necessary as a water source in this explanation..." See more at the article link below: