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If' II II II ~ ~ ~ ~ ~ - - - ~ - - - - ~ ~ Dr. Johnson found evidence in the geologic record for floods 3 to 5 times larger than that of 1911. He based this conclusion upon the size of the drainage basin, the size of bedload the river carries, and the fact that on topographic maps, tributaries appear truncated where they reach the valley. Such a flood would be like that of the Big Thompson north of Denver. It would wipe out the town of Dolores completely. Gravel pits would add only increased sediment to such as disaster. Nevertheless, this evidence shows the power of the Dolores River. In addition to flood frequency, other factors make the Dolores River dangerous. First is its high gradient. Steepness gives the river power to shift its channel both gradually and suddenly. A second danger is confinement. Valley walls often less than 1,000 feet apart force together Highway 145, fields and gravel pits, homes and people. The town itself has space to be only 3 blocks wide! Most of the San Juan Skyway, and all the pits, fields, river, and people are in the floodplain-there is no room to be anywhere else. HOW RIVER mSTORY AND PITS COMBINE: In both 1983 and 1984, spring floods of greater than 6,OOOcfs occurred on the Upper Dolores. Just below its junction with the West Fork and about 10 miles above town, the river makes a sharp bend to move from the northeast side ofthe valley over to the southwest. Either the 1983 or the 1984 flood sent the river out of banks where it made this turn and ripped all the soil off a long expanse of floodplain. Montezuma County officials eyed the devastation and decided to convert that ruined land into a gravel pit. Thus was born the first large pit complex upriver, Twin Spruce Pit, approved in 1985. (Information is from Jack Akin who has lived one mile below what is now Twin Spruce since boyhood.) All other pits including the Line,Oamp;',K,oenig, and Sunnyside were dllveloped since Twin Spruce and ' doWnriver from it. None of these pits has yet faced a flood of 6,000 cfs, let alone a very large flood of 8,000 cfs. The last 8,OOO-cfs event happened in 1949. Will we get another three this century? All this gravel development has been dug into the floodplain in harm's way without benefit of any geologic or hydrologic study under a system where the County Commissioners and pit operators just want gravel, and the Mined Land Reclamation Board is set up, to see they get it in an orderly manner! Up to now, they have been supported by a county full of people who exclaim, "Why, those pits are perfectly safe. They have been there for years," or" We will worry about another flood when it comes, we have always had floods." But here is what Twin Spruce has in store for us: Eight rectangular ponds in a line replace the floodplain-ponds which some locals call beautiful but tourists on the San Juan Skyway think are sewage lagoons. Ponds full of fish that must be fed by hand because'there is no natural vegetation surrounding them. Ponds nobody is allowed to fish in and that wildlife cannot approach because they are too steep. From wall to wall across the valley we have (1) the highway, (2) the long line of ponds, (3) a line of subdivision houses, (4) the Dolores River. Land all slopes down toward the river. Just above the ponds the Dolores channel still switches across the valley in its tight bend. Dr. Blair found only a sliver of gravel road to separate that bend from the empty channel the river used to scour the land in 1983. The road surface is only 2 feet hig.her than the river's