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I I f4R. STAPLETON: MR. SLIZESKI: "How about channelization?" "Channelization of the South Platte has been in our planning, in our survey planning as we call it, for some time. General Walker had instructed us in April to provide him with more detailed plans on channelization. Now what we have in the South Platte Basin, up in the vicinity of the Columbine Country Club district, is a channel capacity of something like l7,OOO cubic feet a second. At Hampden Avenue bridge it has in the vicinity of 25,000 cubic feet a second capacity, and varying amounts on down stream. Generally, what is called the channelized section from Hampden Avenue to the north edge of Denver has reason- ably good capacity. From the fact that you can get these extreme rainfall cells on any of these 42 tributaries and some of them are quite large, take plum Creek, this has 324~ square miles of drainage area above the mouth; Bear Creek has 392,~ I belieye, about the same magni- tude. Even some of the smaller, or lesser known, tributaries like Big Dry, Arapahoe, and Little Dry right through Englewood, all have sufficient drainage area there that if you get these cells like we had in this June flood of ten inches in a matter of three or four hours - this is the cell, according to our hydrologic information, that hit there just at Palmer Lake and at the Arkansas-South platte divide on plum Creek and then below this there was another ten-inch cell right above Castle Rock - rainfall intensities of that magnitude, particularly in this area where you have your extreme stream slopes, always bring down this flood wave. I believe, when we are talking about the protection of Denver, say to the year 2000 when Denver's metropolitan population may be on the order of two million people or more, it is essential that Denver be protected fully from a catastrophe such as has just happened. Our long-range planning is to develop full protection for Denver which then