"Extreme Drought" Continues, but McKenzie has Hidden Reserves
By Adam Spencer, Communications Specialist
As this weekend brings a potential record-breaking heat wave, the "Extreme Drought" conditions will worsen for the Willamette Valley.
According to the US Drought Monitor, the entire State of Oregon is facing "Moderate Drought," with over 80% of Lane County in "Severe" or "Extreme Drought."
In Eugene, for the rainy season starting in October 2020, we are 28 inches short of our average rainfall.
Up in the mountains, precipitation at the McKenzie Pass tracked with the average until this spring's extremely dry April, according to the National Resources Conservation Service. We received a good snowpack, but that hot April melted the snow away, and the "Snow Water Equivalent" in the McKenzie has plunged below average, joining the previous three years (2018, 2019, and 2020) as below-average precipitation years to continue the drought.
At this time, however, EWEB does not anticipate that we will need to institute water rationing measures by the end of this summer.
In the McKenzie River Basin, we can actually count on years of stored water supply, thanks to the McKenzie's unique geology.
The McKenzie is born from the lava rocks of the "New Cascades." These volcanic mountains are young, geologically speaking, and their porous igneous rocks act as filters for the snow that falls on their slopes. It takes precipitation approximately 6-7 years to percolate through the mountains' natural lava rock filter, finally emerging as springs that become the McKenzie River.
Visitors to Clear Lake can see the McKenzie's crystal-clear water as it emerges from its multi-year cleanse. This mountain-sized filter also provides some of the cleanest drinking water in the nation for nearly 200,000 people in Eugene.
In fact, during peak water demand season in August, our intake at the Hayden Bridge Water Filtration Plant is pulling in just 2-3% of the total river volume, so even in drought years like this one the McKenzie is dependable.
Climate change will bring more droughts and more flooding alike, and we'll have to adjust. Global temperatures are rising, meaning we'll receive less precipitation as falling snow.
Warming temperatures will continue to fuel massive fluctuations in the jet stream as well, causing more frequent, pronounced swings in the El Niño Southern Oscillation. For the Pacific Northwest, both El Niño years (which bring warmer-than-average winters) and La Niña years (colder winters) bring in 2.5 inches more rain than average.
With the McKenzie's underground lava rock reservoirs, the wet years will help us through the dry ones, as above-average precipitation in 2017 and 2016 help abate our current drought. EWEB closely monitors the McKenzie watershed for drought concerns, floods, Harmful Algal Blooms, and other hazards.
If water levels ever start to get too low, we will first send a "Water Shortage Advisory" that asks for voluntary curtailment of water use. If water levels continue to decline, we'll issue a "Water Shortage Alert" that mandates water curtailment. Finally, we'll declare a "Water Shortage Emergency" that restricts water use strictly to culinary and sanitary needs.
Again, EWEB will not likely issue Water Shortage notices this year. Nevertheless, it's always good to get in the practice of using less water. The less water we use in Eugene means there's more cold McKenzie River water cooling down the Willamette for our native fish who require cold water to survive. Using less water is also a great way to save money!
To help our customers get into a water conservation mindset, we are launching "Water-Wise Wednesdays" to share tips, products, and life-hacks to remind us of ways we can do our part to reduce our water consumption.
Check in with us each week through the summer to learn about "Water Wise" techniques for your lawn and garden, positive practices in the home, low-flow toilets and other products that EWEB rewards you to buy and install, and more.
Our first "Water Wise" tip is for gardeners out there: With this record heat wave, make sure to water your lawn, gardens, and landscaping early in the morning or late in the evening. If you water during the heat of the day a lot of it will simply evaporate off. Watering in the morning or evening allows the water to settle in, drop down into the soils, and get to the roots, where plants need it most.
Check in next week for another Water-Wise Wednesday, and rest assured that we'll be watching the river and the forecast to make sure there's enough water for us all to enjoy.
