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

Curtailments come to the Chehalis River basin

Notice applies to outdoor water use only—mostly irrigation

The curtailment notice affects junior water right holders.

After an unseasonably warm and dry May, we have notified 93 junior water right holders in the Chehalis River basin that their access to surface water for irrigation is curtailed until streamflows increase in the state’s second largest watershed and drainage basin.

The water users have rights that are junior to (younger than) the 1976 instream flows set by state rule for the basin. Those junior water right holders need to stop diverting water from the Chehalis, Newaukum, Satsop, and Wynoochee rivers when flows are not being met to keep the water in the stream. We sent notification letters to the 93 junior water right holders on May 31.

This is the fourth consecutive year we have issued curtailment orders or notices for junior surface water irrigation uses in the Chehalis basin to comply with the regulation requirements. The curtailment notice does not apply to indoor water use or water for livestock.

As we’ve done in prior years, our staff will periodically visit the basin and are available to answer questions in person, by telephone, or email.

Check our website to see if instream flows are being met:

·        Lower Chehalis watershed

·        Upper Chehalis watershed

Unusual May weather

The Chehalis basin receives most of its runoff from rain, with some minor contributions from snowpack at higher elevations in headwater streams in the southern Olympic Mountains. Streamflows in the basin are lower than normal for this time of year. It’s been warm and dry in the Chehalis River basin and there is little melting snow left to compensate for the tightening water supply.

Instream flows protect rivers

The Newaukum River

We are required by law to protect senior water right users and adopted streamflows for rivers and streams to make sure there is enough water to meet the needs of people, farms, and fish. One of the most effective tools for protecting streamflows is to set instream flows, which are flow levels adopted into rule.

An instream flow rule was established in 1976 for Chehalis basin streams. Since then, newer water rights have been issued that are junior to the flow rule. When flows drop below the adopted levels, junior water rights (those established after the instream flow rule was adopted into law) can be temporarily interrupted in an effort to keep the protected amount of water in the stream. This means junior water rights are curtailed from withdrawing water until streamflows rise above the established flow levels.

Setting instream flows protects our streams, rivers, and lakes from new withdrawals that would harm instream resources including fish, wildlife, recreation, aesthetics, water quality, and navigation.

Read more about protecting streamflows. 

By Kristin Johnson-Waggoner, Water Resources Program