PORTLAND, Ore. -- Nearly 50 days without measurable rain, combined with hot, dry conditions, has made reservoir levels in the Willamette Valley the lowest in six years. Additionally, forecasts are not predicting enough precipitation to alleviate the ongoing drought in the Pacific Northwest. To help the public understand the conditions, the U.S. Army Corps of Engineers, Portland District will host an info session Thursday, Aug. 5th from 12-1 p.m. to update the public about lake levels and recreation opportunities in its 13 Willamette Valley reservoirs.
The Willamette Valley Project depends on spring and early summer rainfall to refill and lack of precipitation only allowed the system to refill to 67.4%. The lack of measurable rain in the past 50 days has only exacerbated the situation.
The Corps invites the public to attend the session to learn more about current operations, future forecasts and impacts to the Willamette Valley System.
Date: Thursday, August 5th, 12-1 p.m.
Link: https://usace1.webex.com/usace1/j.php?MTID=m2911e4975cb2e7c7922648c2909452b3
Call: 1-844-800-2712 (US) (Call-in toll-free number)
Access Code: 199 747 0306 #
Year-to-date precipitation across the Willamette was 82% of normal, as of Aug. 2. The snowpack is 0% of median for the Willamette – there is no snowpack left. Snowmelt helps keep reservoir elevations up in the summer if it lasts and matches outflows – but it only accounts for roughly 10% of the system’s storage – there is no snowpack left this year.
The Corps manages reservoir inflows based on a “rule curve,” or the authorized maximum elevation on a given day to balance flood risk and storage for authorized purposes. The Willamette Valley Systems’ reservoirs are kept lower in the winter to reduce downstream flooding and refilled in the spring to prepare for recreation and adequate flows for fish.
Portland District encourages the public to visit its “teacup diagrams” before heading out to recreate. Willamette River Basin teacup diagram: https://www.nwd-wc.usace.army.mil/nwp/teacup/willamette/ or http://pweb.crohms.org/nwp/teacup/willamette/.
Willamette Valley Project: The Willamette Valley Project’s 13 reservoirs are currently 45% full. System-wide reservoir storage are 55% below the rule curve.
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Portland District’s 150th Birthday: Portland District is one of the nation’s most comprehensive and diverse civil works programs and has been supporting the people of Oregon and southwest Washington since 1871. Throughout its 150-year history, the District has been operating locks and dams along the Columbia River, managing flood risks in the Willamette Valley and Rogue River Basin, maintaining Oregon's coastal waterways for navigation, and leading the Nation in hydropower generation. The team of more than 1,400 civil servants manage these missions all while ensuring equal attention is paid to environmental protection and restoration, fish and wildlife enhancement, and world-class recreation opportunities.