Lowest Rainfall on Record for Eureka/Several Rivers at Record Minimums for This Time of Year

For Eureka, this was the second driest December on record. But that simple fact just scratches the surface of how little water this county has received in 2013.

Normally, about 40 inches of water pours from the skies above Humboldt’s biggest city annually.

However, according to Ryan Aylward, Meteorologist with the US National Weather Service, rainfall in this notoriously watery town sunk to 16.6 inches this year–a whopping 4.57 inches below the previous record low of 21.17 inches set way back in 1929. 

That’s right.  Eureka is not just at a record low in 2013. It’s a long ways below the last record low.

And it is not just Eureka. The whole county, in fact, the whole state, is dry.

Some areas are much worse than others. Ukiah, for instance, had a previous low of 19.98 inches of rain in one year.  But, this year, it only gathered a mere 7.5 inches of rain. That’s less than half the former record.

The problem isn’t just lack of rain. It is the lack of snow pack, too.

The above graphic from the National Weather Service contrasts the snowpack on this date last year (on the right) with the snowpack this year (on the left.) Notice the minimal amount of snow this year compared to last. Though, to be fair, November and December of 2012 had above normal precipitation.

However, here’s another way of looking at the situation.  Below is a graphic of the water content in the snowpack of Northern California provided by the Department of Water Resources.

The pale blue heap shows the average water content. The red line shows the content from the disastrous drought winter of 1976-1977. Above it is the thin blue line depicting last year. And that dark blue line barely nudging its way above the bottom–that’s this year’s water content in the first month of the season. Now, of course, there are several more months to go but, this isn’t a good start.

Snow pack is at 11% of normal here in Northern California. We’re seriously behind.  According to the California Department of Water Resources,The mountain snowpack provides as much as a third of California’s water supply by accumulating snow during our wet winters and releasing it slowly when we need it during our dry springs and summers.” 

Our rivers are running at levels seldom seen before in this season, too.  A spot check shows that several of them are at record lows for this time of year. The gauge on the Klamath at Orleans, for instance, shows that the minimum discharge ever recorded on December 30th was 2440 cubic feet per second. Or, that was the minimum. Yesterday, the discharge had dropped to 1830 cubic feet per second–600 cubic feet below the previous record for that date.

The Van Duzen at Bridgeville has never been recorded discharging less than 21 cubic feet per second on December 30th but, this year, it was discharging 19 cubic feet. Note that both of these previous minimums were in 1977 which according to the Humboldt County Operational Area Hazard Mitigation Plan was the driest on record.

The report goes on to say,

The 1977 extreme California drought conditions affected water supplies for civilian and industrial interests throughout Humboldt County and were some of the worst in the County’s history. Not only were water supplies compromised for the County’s usage, but the drought forced neighboring counties to petition for additional drawdown of water resources allotted from Humboldt County… . If Humboldt County were to experience a drought like that of 1975-77 season, the economic, cultural, environmental, and social impact could be devastating not only to Humboldt County but also to counties and state projects that depend on water received from Humboldt County.

One impact to the Eel, which wasn’t anticipated in the report, just occurred. PG&E, which has dams on the Eel (see map here) and normally releases at least 100 cubic feet of water per second (cfs) this time of year in order to help salmon migrate has received permission to greatly reduce this amount. The Potter Valley Project, PG&E writes,

…is experiencing the driest year on record and, as a result, can no longer sustain the current minimum flow requirements while also ensuring the safe operation of the Project due to extremely low storage levels in Lake Pillsbury.  A reduction in discharge from Lake Pillsbury is needed to eliminate the risk of vertical bank collapse in the reservoir bed that could occur unless discharge is reduced. (See here for the full text of the request.)

PG&E requested and received permission to immediately cut the minimum amount of water they must release from 100 cubic feet per second to 25 cubic feet per second on the Eel River. EPIC’s Gary Graham Hughes wrote that this “clearly present serious challenges for recovering salmonid populations in the mainstem and lower sections of the Eel River.”

The Eel River while not at a record low is at a level usually found in August. This is much lower than normal December flows. This month, the middle of the salmon migration, usually has flows that average almost a 1000 times the current amount.

Scott Greacen, Executive Directer of Friends of the Eel River, says this is concerning. He acknowledges that in recent years there have been “reassuring runs of Coho” salmon but, he says, the low water flow is going to cause problems.  “In situations like this, it is a real reminder that even the runs we have had in the last few years are vulnerable.”

According to an article in the Redwood Times, the North Coast is already seeing a serious impact. Virginia Graziani writes,

As of Dec. 3,…the Van Arsdale Fisheries Station had counted only 18 fish coming up the fish ladder to spawn in the stretch of the river between the two dams.

On the same day last year the total count for the season was 3400 chinook.

Ryan Aylward, Meterologist for the US Weather Service says that the most reliable forecasts for the next two weeks show very little precipitation. There is, he says, ” A little front that will slide through on the 3rd.” But it isn’t expected to drop much water.

The first storm we get, Aylward says, will do little to fill the rivers. “With soils dry now for awhile, a lot of rain is just going to go into the soils. It will take a storm or two to bring up the flows.” In addition, he says, because we are already 11 inches behind normal, it will be hard to catch up to a normal year. Long range forecasts show “persistent drought into March.”

“It looks more and more that the water year as a whole is going to be below normal but,” he says, “there is still time.” 

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