PORTLAND, Ore. -- As warm, dry weather continues, the U.S. Army Corps of Engineers, Portland District is seeing a worsening water year as it strives to refill 13 Willamette Valley reservoirs for the upcoming recreation season.
The Willamette Valley Project depends on spring and early summer rainfall to refill and lack of precipitation is making it difficult to fill multiple reservoirs. To help explain the situation, Corps staff will host a virtual public information session, Thursday, May 20th from 12-1 p.m.
The Corps invites the public to attend the session to learn more about current operations, future forecasts and potential impacts to the Willamette Valley System.
Date: Thursday, May 20, 12-1 p.m.
Link: https://usace1.webex.com/usace1/j.php?MTID=m09a0fd1d3f712d087fbb7fa821490011
Call: 1-844-800-2712 (US) (Call-in toll-free number)
Access Code: 199 320 2562 #
The Corps encourages questions but asks participants to send any questions in through the “chat” function in the WebEx during the call.
Year-to-date precipitation across the Willamette was 76% of normal, as of May 17. The snowpack is 51% of median for the Willamette. 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.
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 67% full. System-wide reservoir storage are 33% below the rule curve. Year-to-date precipitation in the Valley is 76% of normal. Willamette Basin snowpack is currently 51% of median.
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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.