Chance for recovery?
ASHLAND — When Jim Pendleton sees cracked mud in the bed of Emigrant Lake in late fall, he looks skyward and wonders whether winter will bail him out or leave him high and dry.
Pendleton manages the Talent Irrigation District, which uses water from Emigrant and its two sister reservoirs of Hyatt and Howard Prairie to feed the farms, ranches and vineyards of the Bear Creek Valley.
But drought caused those reservoirs to crawl into this winter at their lowest levels in 20 years. On Nov. 30, Emigrant was 13 percent full, Howard Prairie was 9 percent and Hyatt was 25 percent. Their recovery by the start of the next irrigation season depends on how much snow accumulates in the mountains above them by April.
"If we could get to 80 percent full by that time ... we'll be in great shape," says Pendleton, whose TID controls the majority of the three reservoirs' water.
An analysis of Natural Resources Conservation Service data reveals that there's statistically a 50 percent chance that the three reservoirs will recover by late spring, with the late-winter snowpack — and not spring rainfall — appearing to be the determining factor.
In the years since 1960 in which Hyatt, Howard Prairie and Emigrant reservoirs were drawn down amid drought years, half the time the ensuing winter's snowpack was as much as 150 percent of average — enough to get the reservoirs 80 percent full before summer.
Yet in the other half of those heavy drought years, the ensuing winter's snowfall underachieved — often in the range of slightly more than half of the average snowpack, NRCS data shows.
During those years, not only did the reservoirs fail to recover, they sometimes ended up lower that spring than they were the previous fall, records show.
"That doesn't generate a whole lot of hope," says Julie Koeberle, a hydrologist with the NRCS's snow survey program. "But it does send a message that at least it (recovery) happened and there's hope it will again.
"If I looked at this data and there hadn't been recovery, you'd get a different message from me," Koeberle says.
Meteorologist Steve Pierce's message is everyone should have a good idea by Jan. 15 whether this current winter creates reservoir recovery in Jackson County or not.
Ocean currents are favoring an El Niño pattern that typically generates warmer storm patterns that bring more rain than snow to southwestern Oregon, a pattern that historically doesn't help snow-dependent reservoirs such as Hyatt, Howard Prairie and Emigrant.
Typically, mid-January snowpack can foreshadow what lies ahead for the rest of the winter in the Cascades, Pierce says.
"If we get to Jan. 15 without a good snowpack in the Cascades, the odds go way down that we'll get to average," says Pierce, president of the Oregon Chapter of the American Meteorological Society.
The water years of 1992 and '93 tell how different the snow season can be after low-water conditions the previous fall at Hyatt, Howard Prairie and Emigrant.
The three reservoirs limped into the 1991-92 winter at levels far higher than this past fall. On Nov. 30, 1991, Hyatt Lake was at 30 percent of capacity, while Howard Prairie was at 36 percent full and Emigrant was at a scant 20 percent full.
The ensuing winter saw a snowpack at just 20 percent of average on April 1, and Emigrant started the summer irrigation season at 61 percent full. Howard Prairie and Hyatt were at 24 percent and 34 percent, respectively.
The following fall saw reservoir levels even lower than this year.
On Nov. 30, 1992, Emigrant sat at just 3 percent full, while Hyatt and Howard Prairie were 18 percent and 11 percent of capacity, respectively, NRCS data shows.
But a funny thing happened on the way to this water pity-party. Heavy snows blanketed the basin early and often, creating a April 1, 1993, snowpack that was a whopping 127 percent of average.
By the following June, Emigrant was a smidge under full, and Hyatt and Howard Prairie were each over 80 percent capacity.
The reservoirs had recovered and didn't suffer low-water woes again until 2001.
"What it goes to show is that, just because we started low in December, it doesn't seal its (reservoirs') fate," Koeberle says.
Having just a dozen water years since 1960 that fit this formula for reservoir recharge isn't the deep data set that scientists prefer when making predictions on whether the weather this winter and spring will wash the 2014 drought away.
"What's interesting to me is how few years it's been this low," Koeberle says. "We need more data. But I don't want any more years like this just to get more data."