Water Matters: Drought!

Drought!

Gesundheit! Oh, what did you say?

Drought was just declared for the Olympic Peninsula!

I don’t believe it … it’s been raining. And it’s only May – look at all the green out there. Plus, three months ago we had the biggest snowstorm in decades!

California’s droughts have everything to do with dry vs. wet conditions, but as Washington state law defines “drought conditions” it has nothing to do with dry weather.

State lawmakers are responsible for setting criteria on the availability of disaster relief funding for any type of emergency. A drought emergency is to be declared when (1) the water supply for an area is below 75 percent of normal, and (2) the water shortage is likely to create “undue hardships” for water users.

California has a meteorological definition of drought and Washington has a hydrological definition. The state Department of Ecology is responsible for identifying conditions that meet the legal definition of drought so its staff closely monitors winter weather patterns and measures snowpack while consulting other state and federal monitoring agencies.

The Dungeness Snotel station is one of four in the Olympic Mountains and 30+ in the state. Data from all four Olympic Snotel sites are generally reported for the whole range rather than one basin at a time.

This makes good sense because the Dungeness Snotel is at about 4,000 feet elevation, more than 1,000 feet lower than the top of the watershed. The historical record for the Dungeness station since installation in 1999 shows that snow is normally melted out by early May, compared to early or mid-June for higher-elevation stations.

Amazingly, and to the disappointment of skiers, the dump of snow we got in Sequim was not predictive of what happened high in the mountains. Unlike storms from the coast that dump their load up high and leave us in the rain shadow with an attractive dusting of snow, this storm was like the “lake effect” variety that hit Chicago hard after building up moisture over the Great Lakes. Our big snowstorm came from the north, crossed the relatively warm Strait, and dumped its snow load at low elevations.

I am in full agreement – it is hard to believe that such a snowy winter in Sequim didn’t create a bounty of snow in the mountains and replenish our glaciers.

In the Pacific Northwest, drought is not about recent rainfall or the bounty of flowers and spring growth, but instead it’s about the snow you don’t see – or see less of every day – in the mountains. The state definition is consistent with this. Hydrologists and other snowpack watchers find limited delight in “unseasonably” sunny and warm weather in April and May, because it means the snowpack is melting and that could mean trouble by July or August for certain populations, human and otherwise.

The undue hardship listed as the second criteria in the state’s definition of drought is that anticipated for late summer by farmers who could run out of irrigation water and communities whose water supply depends on snowmelt. Less politically visible are the salmon whose water supply also depends on snowmelt. Indeed, many facts in our world are not visible and obvious, but that doesn’t mean they’re not real.

Hydrology-ecology connections

As mentioned in the last “Geek Moment,” the savings account for Water Year 2019 reached its maximum balance by the end of April … when snow and ice in the mountains stopped accumulating. Saved precipitation in the form of ice determines what the Dungeness River flow levels will do during the heat of summer.

And how goes the River flow, so goes aquifer recharge, well water supplies, wetlands and creeks.

The US Geological Survey estimates that a quarter of the water that recharges our aquifer comes from Dungeness River seepage. When the total amount of water carried in one year by the Dungeness River drops, then the fraction seeping into the aquifer also drops.

Or, if that total volume comes in a few concentrated torrents from big storms rather than less intense rainfall spread throughout winter, then the flow velocity hinders infiltration and more of that rain will run off into the Strait.

Gardeners are very familiar with the difference between a good, persistent “soaking” rain and a brief squall that erodes the topsoil and runs off into the nearest ditch.

As the climate warms, trends indicate that the total number of inches of rain we get isn’t likely to decrease, but the way we get it is likely to transition to larger and warmer storms in winter – and drier springs, summers and falls.

This is fortunate for sun lovers but unfortunate for the natural systems dependent on the seasonal hydrologic patterns that have evolved over thousands of years. With less ice and snow contributing to snowmelt and the annual snowpack melting sooner, streams run lower and incoming salmon don’t have as much wetted streambed habitat to spawn in as they evolved with.

As we and Californians know all too well, increasing dryness also makes our traditionally verdant landscapes susceptible to wildfire. And that’s a different emergency declaration …

It comes down to this: many problems in our world have no obvious solution, but climate change is not one of them.

Sources: USGS, 1999, Hydrogeologic Assessment of the Sequim-Dungeness Area; ca.water.usgs.gov/california-drought.

Geek moment

City of Sequim encourages water conservation starting now, especially outdoors. We have information about Washington’s drought on our website (www.sequimwa.gov), including ideas for saving water, energy and money all at the same time.

For those with private wells concerned about drought risk, the Washington Department of Health suggests learning about your source from your well log or pump installer. The following factors may indicate higher risk of pump failure:

1. Shallow well (less than 50 feet deep).

2. Low flow rate/capacity/yield listed on well log (less than 10 gallons per minute).

3. If the well pump has sputtered or failed in the past.

In all cases conservation would be wise. To track your situation you could measure and record your well water level at the same time each year, or once each season. Here is a fact sheet on measuring the water level yourself or with a contractor: www.doh.wa.gov/portals/1/Documents/pubs/331-428.pdf.

For the 2019 Water Year (started Oct. 1, 2018):

• Rain in Sequim through May 27 at the Sequim 2E weather station (sea level): Total rainfall = about 13.5 inches.

• River flow at the USGS gage on the Dungeness (Mile 11.2): Currently = 754 cfs. Range for the past month = 289-944 cfs – a little higher than normal.

• Flow at Bell Creek entering Carrie Blake Park: trickle or none; Bell Creek at Washington Harbor= flow generally 2-3 cfs in spring.

Ann Soule is a hydrogeologist immersed in the Dungeness watershed since 1990, now Resource Manager for City of Sequim. The opinions expressed are those of the author and do not necessarily represent policies of her employer. Reach Ann at columnists@sequimgazette.com or via her blog at watercolumnsite.wordpress.com.