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Sept. 18, 1999 By Jim Mimiaga For the first time since the reservoir was completed in 1984, controllers of McPhee dam were forced to spill water downstream ... in September. Typically water is released into the lower Dolores River canyon during the annual spring run-off, but this year is far from typical. Heavy summer rains have put the reservoir at capacity, and that combined with low demand for irrigation water contributed to an unprecedented release date. "We've had more water this summer than anyone can remember, and so the demand is lower than normal," said John Porter, manager of the Dolores Water Conservancy District, which controls downstream discharges at McPhee Reservoir. Irrigation draws dropped the man-made lake four feet in June, he said, but late July and August precipitation quickly brought it back to capacity. Cool weather and more than enough rain for farmers (especially alfalfa producers) left no need for the stored water, prompting a two-week-long spill needed to make room for next year's spring snowmelt. "We had to vacate some space to get ready for winter," Porter said. "This is the first fall-time release since the dam was in place. We did not want to go into winter with a full reservoir." Normally the lake is down 15 to 20 feet by summer's end, he said. The release of 50 additional cubic feet per second every three hours, known as a "ramp-up," began Sept. 6, reaching a peak of 800 cfs two days later. Flows held there until midnight Thursday, when gates began slowly closing, curtailing the spill by 25 cfs every three hours. That will continue until Monday, at which point the flow will be lowered to 70 cfs. By Nov. 1 it will be down to 40 cfs, where it will stay until spring. Flow releases are carefully measured to help protect quality fishing waters and habitat below the dam. In-flows upriver from McPhee are 266 percent of normal this year, while Montezuma Valley Irrigation Co. (MVI) demand for water was down to 78 percent of the long-term average, Porter said. Water sold directly from McPhee for irrigators was at 35 percent of what is considered normal, based on five-year running average. MVI receives most of their water stock from Narraguinnep and Groundhog reservoirs, and also directly from the Dolores River at the Great Cut Dike. All this atypical fall whitewater has been a boon for river runners, both private and commercial. Boaters require flow conditions of at least 800 cfs for a decent run. "It has been good. We had a few extra trips because of the fall spill, in fact, we've got a trip running right now," said Barbara Klema, co-owner of Peregrine River Outfitters in Durango. "We could have taken better advantage if there had been a bit more advance notice, but it's been really nice, especially for customers who just called in. Normally a great trip like the lower Dolores is not available this time of year." She added that area river guides have been able to work longer this season compared to recent years. Bill Hatcher, a kayaker from Dolores, reported quality conditions on a popular stretch of Class 2 rapids from the Bradfield Bridge to the pump station. "I was just on it and it was really nice," he said. "I have never run that stretch this time of year, but when the flows are that high you have to take advantage. "I've been boating on desert rivers for 15 years and generally it is figured that the water will flow in the spring, so this was a nice opportunity." For Saturday the Bradfield Bridge/pump station stretch will be running around 400 cfs, which is good enough for tubing and kayaking, but not rafting. |
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