Eighty-foot Texas canyon in three days

An Oct. 5, 2007 article from the Associated Press reports on a new canyon which was gouged out of the earth by a Texas reservoir overflowing its dam. It cut an 80-foot deep gorge in just three days. The article then states, "[That] doesn't compare with the world's most famous canyon. It took water around 5-6 million years to carve the Grand Canyon, which plunges 6,000 feet and is 15 miles wide at its widest point." Let's take those figures and compare the two. The Texas canyon was formed by 70,000 cubic feet of water emptying from the reservoir. It cut 80 feet deep in three days. Take those same ratios and apply to the flood of Noah. Water flowed in and receded for just over a year, but let's just use the nice, round number of 350 days for easier math. By this same ratio, over the course of 350 days of similar flow the Grand Canyon would be 9,333 feet deep! And that is just using the flow rate of one little Texas lake. What would a global flood which drowned the tallest mountains on earth accompanied by massive tectonic and volcanic activity do? The Grand Canyon should have been over 50% deeper after just a year of flooding. So how can it have taken the "mighty" Colorado River 5-6 million years to cut the Grand Canyon?
"Texas Canyon Was a Rush Job" (AP) by Michelle Roberts Oct. 5, 2007