H. Scott Oviatt Snow Survey Supervisory Hydrologist USDA NRCS Snow Survey and Water Supply Forecasting rcs/main/or/snow/ NRCS Oregon Technical Advisory Committee October 1, 2015 Review of Water Year 2015 Conditions – Future??

SYNOPSIS of 2015 Water Year in Oregon 1.Lack of sustained Pacific storm impacts 2.Near-record warm temperatures 3.Lack of snowfall and rain in place of snow 4.Minimal snowpack development **Resulting in surface water shortages**

Willamette Rogue/Umpqua Klamath John Day Owyhee/Malheur

Willamette Historic Snowpack Klamath Historic Snowpack John Day Historic Snowpack

Grande Ronde, Burnt, Powder & Imnaha Historic Snowpack Owyhee Historic Snowpack

67% OR in Extreme Drought – 100% in Severe Drought

2015 SUMMARY and POTENTIAL FUTURE IMPLICATIONS Warm temperatures resulted in lack of snow and snowpack Streamflow volumes decreased dramatically (to record low in many locations) through the water year due to the lack of snowpack and precipitation shortages (January through March) Most major basins are observed significantly decreased April snowpack, especially over the last 5 years April through July precipitation was near normal, but was not supplemented by snowmelt runoff resulting in record-low streamflows Dry soil profiles will most likely take multiple years of normal or above normal snowpack, precipitation, and cooler (near-normal) temperatures to restore conditions to ensure adequate runoff throughout the summer and early fall Burned areas and locations with extremely dry soil profiles are susceptible to flash flooding and landslide events

Thank you!