OGDEN -- A wet spring and cool summer have left Top of Utah water managers in the unusual position of having plenty of water to manage.
"The water managers are in a position which is enviable," said Brian McInerney, hydrologist for the National Weather Service. "They need to dump water to make room for the coming year, but what if it's a dry year?"
That's a problem water managers like to have. In Utah's drought years during the first half of this decade, they were looking at low or even dry reservoirs this time of year, hoping that the winter would fill them.
This year, he said, everything lined up well.
"We had a normal runoff, a good, efficient runoff," he said. "A lot of the snow in the mountains made it into the reservoir."
There was normal snowfall, he said, but in June the skies opened.
"We had 400 to 500 percent of June precipitation right at the end of the runoff period," he said, so instead of drawing from the reservoirs in June to irrigate crops, "we were filling them all the way through to the third week of June because of the rainfall."
At that point it quit raining until Monday, he said, but it didn't matter that much.
Temperatures stayed cool, cutting down on irrigation, so the end result is that reservoirs are relatively full.
Tage Flint, executive director of the Weber Basin Water Conservancy District, said he expects the water year to end Sept. 30 with about 25 percent more in storage than last year.
The larger reservoirs are the most full. Echo, which holds 73,000 acre-feet of water, is 43 percent full. Causey, which holds 7,000 acre-feet, is at 50 percent.
Pineview, which holds 110,000 acre-feet, is 66 percent full.
Willard Bay, which can hold nearly 200,000 acre-feet of water, is at 95 percent.
"This will allow us to feel better about next year regardless of what kind of winter we have," he said. He will have to watch the levels of his reservoirs, letting water out if it looks like a heavy snow year, but that's the sort of work he likes to have.
On the other hand, he dares not assume the wet, cool trends will continue. He can remember years when, even starting where his reservoirs are now, the winter was so dry they didn't fill.
"We will go with our irrigation season until Oct. 15," he said.
"This will establish our end point, because we can pretty accurately estimate what our drinking water demand will be, and at that point we'll start doing estimates and taking Brian's forecasts to estimate where we'll be."
On Monday, McInerney issued a summary of Utah's summer that shows why Flint has water to talk about this year.
First, he said, it rained a lot in June. Except for the southwest corner near St. George, almost all of the state got at least 150 percent of normal precipitation in June, and some areas had more than four times normal rainfall.
In July, rain patterns crashed, with most of Top of Utah getting less than 50 percent of normal. That continued into August.
What kept things from getting worse was a moderate temperature trend, McInerney said.
In the summer months of June through August, there were only 44 days in which temperatures got above 90 degrees, he said. The average is 56 days, and in 2008 there were 61 days.
The big difference came in the number of days in which temperatures exceeded 95 degrees. There were only 25 days this year, compared to 35 in 2008 and 47 in 2007. The normal number of days that exceed 95 degrees is 23, he said, which means 2009 wasn't abnormally cool, just a lot cooler when compared to the previous several.
Utah has seen a wetter trend over the last several years, he said.
"We haven't been in any drought since 2004," he said. The 2007 water year was dry, "but we had carryover in the reservoirs. But 2008 was good, 2009 was very good, so since 2005 four out of five years have been normal to above average for snowmelt and runoff."
With good snowpack and a good runoff, he said, a dry summer doesn't cause many problems.
What will happen this winter is harder to say.
There is a moderate el Nino, or warming, in the South Pacific, "and in the past, about 10 years ago, they used to be able to put their finger on it and say the American Southwest would be cooler and wetter than normal."
In the last seven years, though, warming or cooling in the South Pacific hasn't been having the usual effects, so "they're kind of stymied, the guys who do long range forecasts."
So it might be wetter and cooler this winter, he said, "but I think if you were going to wager anything, you wouldn't wager much on this."
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