WALLA WALLA, Wash. – The U.S. Army Corps of Engineers, Walla Walla District, invites public comments on the draft Finding of No Significant Impact (FONSI) and Integrated Feasibility Study and Environmental Assessment Report (FR/EA) for the Mill Creek Flood Risk Management General Investigation Study, Walla Walla, Washington.
The Corps and the non-Federal Sponsor, Mill Creek Flood Control Zone District (Walla Walla County), are conducting the study to address the flood risks Mill Creek presents to the community of Walla Walla, Washington, and other communities within the Mill Creek watershed (adjacent lands). This draft FR/EA documents the results of the feasibility study and environmental compliance processes. It presents the process, analysis, results, and preliminary conclusions of the investigations and analysis performed to evaluate potential improvements to the existing Mill Creek Flood Control Project (MCFCP or Project).
The public comment period will begin on January 15, 2020 and conclude thirty days later on February 14, 2020. Public comments may be submitted electronically to the Corps using the online comment form on the Environmental Compliance webpage, or via email NEPANWW@usace.army.mil -- type “Mill Creek GI” in the subject line. Comments must be postmarked or e-mailed no later than February 14, 2020 to be considered as part of the public record. Comments should be mailed to:
U.S. Army Corps of Engineers, Walla Walla District
ATTN: CENWW_PPL-C, Mill Creek Study
201 North 3rd Ave.
Walla Walla, WA 99362-1876
A public meeting is planned for Wednesday, February 12, 2020 at 5:30 p.m. at the Courtyard by Marriott, 550 West Rose Street in Walla Walla, Washington. At this meeting, the Corps will give a presentation, conduct a question and answer session, and accept written comments from interested parties.
The draft FONSI and FR/EA are available in electronic form through the Corps’ website at https://www.nww.usace.army.mil/Missions/Environmental-Compliance/
If you have questions, please write or e-mail the Corps at the addresses above, or call the project Environmental Compliance Specialist at 509-527-7256.
The U.S. Army Corps of Engineers, Walla Walla District (Corps), in partnership with its non-federal sponsor, Walla Walla County, proposes to conduct a general investigation study on the Mill Creek Flood Control Project (Project) in Walla Walla, Washington. The study includes a modernized reassessment of the overall flood risks Mill Creek presents to the Walla Walla community. The study will consider Project capacity, performance, and reliability of several components through a range of alternatives that could be implemented to reduce risks to the community looking forward.
The Project was authorized in 1938 with the single purpose of reducing flood risk to the City of Walla Walla and surrounding communities.
The existing Project consists of four main components:
1) Bennington Dam, which impounds Bennington Lake, an off-channel reservoir
2) Diversion Dam, which diverts flood water through a channel into Bennington Lake
3) Leveed Channel (upstream and downstream of Walla Walla),
4) The concrete channel through downtown Walla Walla. Since the disastrous 1931 flood, life safety risks have increased.
The Project used to be able to divert floodwaters to Yellowhawk and Garrison Greeks.
The flood risk reduction provided by the Project may be insufficient to address current risks, and the number of buildings in the flood zone has tripled and now includes five elementary schools, two middle schools, two high schools, two colleges, six nursing and assisted-living homes, and three hospitals.
A public scoping period was conducted Oct. 15 through Nov. 16, 2018, including a public meeting held Nov. 1, 2018, in Walla Walla, Washington. Information and comments submitted during the scoping period will be included in the permanent public record, and used to identify issues to address in the study, exploring alternatives and identifying potential environmental effects of possible changes to the system. The study process will include additional outreach activities with citizens and stakeholders across the community to gather their thoughts and ideas related to the way we could manage flood risks and other important water resources considerations.
The Mill Creek GI study will also include coordination and consultation with other federal and state agencies to find ways to minimize potential effects to valuable environmental resources, such as ESA-listed fish, water quality, and cultural and historic resources.
The Corps is committed to working with our non-federal sponsor, Walla Walla County, and the larger community to provide safe and sustainable solutions to reduce flood risk in the City of Walla Walla and surrounding communities.
We will keep the public informed by updating this webpage and distributing information to area news media as the study progresses.