The last week of March yielded plenty of benefit for The Dalles’ water supply — about two feet of snow at High Prairie as of March 31 — bringing the seasonal total snowpack to 99 inches.
The question that’s most important to the city’s water supply is how much water is in that snow? As of Monday, that figure was 35 inches of water, or 78 percent of average, said Dave Anderson, The Dalles public works director, who snowshoed into the watershed with water department staff to take the measurement.
“It was our last trip up there for the season and we’re in reasonably good shape,” Anderson said. “We’re certainly in much better shape than we were at the end of January.”
The city didn’t take measurements at the end of January, instead relying on regional measurements done by the Natural Resource Conservation Service that showed water content at between 19 and 37 percent of average in various measurements.
Watershed snowpack measurements have been taken during the winter months since 1983, Anderson said, and December and January typically provide a good share of water for the season.
“At the end of December, we usually average about 10 inches of water,” he said. “By the end of January, we usually average 29 inches. By February it’s up to 38 and by the end of March it’s up to 45.”
While the final measurements of the year didn’t quite reach that March mark, they’re still better than six other years since 1983, including last year.
“Last year was just slightly less than what we measured last year,” Anderson said. “While this won’t be a year when we have an abundant supply from our surface water source, it’s not looking like any kind of shortage that’s a concern for us.”
Measurements showed a good layer of ice next to the ground below the snow, which he said is not ideal.
“We like the ground to be unfrozen and for there not to be an ice layer on the ground under the snow. If [the ice] isn’t present, there’s a better chance for the water to soak into the ground and recharge the ground supplies.”