Watching the water supply:

Southwest Washington bearing brunt of dry conditions

Although we don't expect much rain this time of year, one area of the state stands out for being drier than usual: Southwest Washington and most of the Olympic Peninsula.

The July 19, 2018, U.S. Drought Monitor map classifies

southwest Washington as having moderate drought-like

conditions. Much of the rest of the state is considered

abnormally dry.

The U.S. Drought Monitor map, one of the tools we use to assess state water supply conditions, classifies much of the region as experiencing moderate drought-like conditions. The map is updated weekly and available on our statewide water supply conditions webpage.

Streamflow data also point to low flows in the region.

We’re seeing many rivers and streams in southwest Washington run at record low levels. The Chehalis River near Grand Mound is running at 113 cubic feet per second—a flow level in the 1st percentile, meaning flows are so low they are exceeded 99 percent of the time for this time of year historically. The Willapa River near Willapa is at 20 cubic feet per second, which is in the 1.5 percentile, meaning the flow is exceeded 98.5 percent of the time for this time of year historically. Irrigators, fish and aquatic habitat are most affected by these low flows.

Citing low flows in the Cowlitz River, the city of Kelso has asked its residents to take  

The Chehalis River winds its way west of Chehalis (July 19, 2018). We're
seeing record low flows on parts of the river. 

voluntarily water conservation measures until water levels in the municipality’s water source improve. To the north, the city of Forks and two small Jefferson County water systems are also asking their customers to follow voluntary conservation measures.

NOAA’s climate prediction center is predicting warm, dry conditions for the rest of summer. We are closely monitoring water supply conditions and working with other state agencies to track impacts. If you’d like more detail, read our water supply webpage.

Are we in a drought emergency?

Under Washington State law, emergency drought conditions are identified when water supply in an area has or is predicted to have 75 percent of normal water supplies AND undue hardships expected as a result. 

Drought emergencies are declared using a formal process based on statute. At this time, we have not declared a drought emergency anywhere in the state.

A rain-fed water system

The hydrogeology of southwest Washington is unique. Water supplies rely heavily on rain and less on snowpack from the Cascade and Olympic mountains. This means the region’s water supplies are more sensitive to above-average temperatures and below-average precipitation like we’ve been experiencing.

The effects of the unseasonably warm and dry weather in May led us to issue water use curtailment notices. We asked 88 junior water right holders—mostly irrigators—in the Chehalis River basin to stop using river water until flows increase.  This is the fourth consecutive year we have issued curtailment orders or notices for junior surface water irrigation uses in the basin. It was also among the earliest dates we have curtailed this group of water users.

Office of Chehalis Basin

In 2016, the Legislature created the Office of Chehalis Basin within Ecology. While a main focus of the new office is to pursue long-term flood-damage reduction and restore aquatic habitat in the state’s second-largest river drainage system, the Office of Chehalis Basin is also tracking the impacts of the dry conditions.

By Kristin Johnson-Waggoner, communications manager

Watching the water supply

While you’re out there enjoying this warm and dry weather, there’s another side to the story that we’re continuing to track: How these conditions are impacting state water supplies.

We are seeing dry areas around the state. NOAA is forecasting summer to be even drier and warmer than normal, so our dry conditions are likely to persist until the fall rains return.

This map from USGS shows about half of the 

streamflows in our state are at below-normal levels.
Learn more about streamflows at our statewide
conditions webpage. 

Currently, parts of the state (mostly southwest Washington) are experiencing moderate drought-like conditions. See the U.S. Drought Monitor map below for more detail. However, storage reservoirs for drinking water and irrigation are in good shape.

People and the environment depend on a healthy water supply. Impacts from the current dry conditions will likely most affect irrigators and fish. We’ll continue to track conditions on our website and this blog.

Are we in a drought emergency?

While drought-like conditions are evident, we’re not declaring a drought emergency at this time. Drought emergency declarations for the entire state or part of the state involve a formal, statute-based process. Conditions that could trigger a drought emergency are when water supply in an area is 75 percent of normal and there is an expectation of undue hardship because of deficient water supply. We are watching the situation closely.

Curtailment updates

We issue curtailment orders in parts of the state due to low flows in rivers and streams. Curtailing water use protects senior water right holders and adopted streamflows. Here’s an update:

• In June, we wrote about curtailing 300 junior water users along the Yakima River and its tributaries. Since then, the U.S. Bureau of Reclamation announced that senior and pro-ratable customers of project water will receive 100 percent of their water supply this summer. This is an improvement over June, when Reclamation had forecasted 96 percent. Due to this revision, which Reclamation attributes to reduced demand during the month of June, we are notifying the junior water right holders in the basin that they may resume their diversions. 

• In the Methow area, irrigators with interruptible water rights will likely be regulated when river levels drop close to minimum flows. We will provide these water users with a hotline to check if they are allowed to irrigate.

As always, visit our statewide conditions webpage for information on streamflows, temperature, precipitation, and more.

We use several tools to assess statewide water supply conditions, including a weekly map from the U.S. Drought Monitor. This week’s map shows abnormal dryness and parts of the state, mostly in southwest Washington, experiencing moderate drought-like conditions.

By Kristin Johnson-Waggoner, communications manager

Watching the water supply

Snow is piling up at Paradise on Mt. Rainier. Photo: National Park Service webcam

This blog post is part of an ongoing series about water supply. Please click here to read the previous post. If you want to learn more, visit our Washington water supply information page.

It’s a new year and a good time to check in on our statewide water supply. Winter usually puts less pressure on our water supply because of reduced demand for water in homes and less agricultural irrigation. But communities and farms are already starting to plan for the drier and warmer months -- and experts are watching the conditions closely.

Looking back at 2016

For Washington state as a whole, 2016 was a slightly warmer, wetter-than-normal year. Temperature-wise, the state was 1 to 2 degrees warmer than average annually, and March through May tied 1992 for record warmth.

The balmy spring caused our snowpack to melt at record rates. In early April, the state snowpack was slightly above normal. By late May, it was less than 50 percent of normal. This raised some concern that water supplies might be pinched later in the summer, but a switch to wetter conditions and more moderate temperatures in June and July made things manageable. Still, there were some watersheds in southwest Washington where dry conditions caused total runoff during the spring and summer to be even lower than 2015 – a drought year.

This fall, the warmth returned along with long stretches of rainy days. Averaged statewide, October and November were the second-warmest on record (3.3 degrees above normal) and wettest on record (6.61 inches above normal). The pattern changed in December, though, when cooler, drier weather swept in. Most of the state was chilly – with many areas a few degrees below normal – for the first few weeks of the month.

Status of our supplies

We’re starting 2017 with good snowpack. Let’s take a closer look at water supply as of Jan. 5 and forecasts for the future:

The sun peeks out over a snowy scene on Hurricane Ridge. 

The Olympic Mountains have 126 percent of normal snowpack
for this time of year. Photo: National Park Service webcam

Weather and outlook | Looking ahead, state climatologists are expecting La Niña conditions (cool and wet) to shape our regional climate, but there’s a good chance we’ll switch into neutral conditions (neither La Niña nor El Niño) later this winter. Forecast models aren’t clear on temperature heading into spring, but they are predicting wetter-than-normal weather. Beyond spring, the forecast models aren’t saying much.

Mountain snowpack | Mountain snow is critical because it serves as a reservoir during spring and summer, gradually melting and feeding rivers and streams. Our mountain snowpack got a late start this year but is currently looking good. The lower Columbia, central Puget Sound and Olympic regions, in particular, are doing great with more than 125 percent of normal snowpack for this time of year. The mountains near Spokane are somewhat behind schedule, but they’re still looking decent with 77 percent of normal snowpack.

Rivers and streams | Experts are seeing typical conditions for our state’s rivers and streams. Daily streamflows are mostly in the normal range. Flows are dropping below normal during cold snaps, when snowmelt stops.

Agriculture | The U.S. Bureau of Reclamation reports that storage levels at the five reservoirs in the Yakima River basin, a major agricultural center, are at 107 percent of normal. Precipitation from October to the end of December is about 94 percent of normal in the Yakima region.

Drinking water | Drinking water supplies in our state’s big cities are in good shape. At the beginning of September, Everett’s water storage was 110 percent of normal for that time of year. Seattle’s combined reservoir storage is also above normal for this time of year. Tacoma reports that both precipitation and snowpack levels are above normal at the Lynn Lake monitoring site near the Howard Hanson Reservoir.

How you can help

We all have a role to play in conserving water, even in winter! Here one way you can make a difference:

• Insulate outdoor spigots to prevent them from freezing and bursting. If you have an outdoor garden hose, remove and drain it. This video from the Saving Water Partnership has more information.

For more tips, visit our water conservation page.

By Kristin Johnson-Waggoner, Water Resources Program communications manager