News Release
| Release Number: | 98-048 |
| Dated: | 6/24/1998 |
| Contact: | Public Affairs Office, 503-808-4510 |
Portland, Ore. -- The U.S. Army Corps of Engineers is seeking final public comment on the proposed Dredged Material Management Plan and Supplemental Environmental Impact Statement for the Columbia and Lower Willamette River Federal Navigation Channel.
The plan and SEIS are the result of a five-year Dredged Material Management Study conducted by the Corps from 1993 to 1998. Such studies are now required for all Corps navigation projects to evaluate cost-effective maintenance over a 20-year period.
Four long-term disposal alternatives are described in the report as ways of maintaining the existing authorized federal navigation channel with increased efficiency; one of the four is presented as the preferred alternative. The Corps, in cooperation with the Environmental Protection Agency, released the report on June 19 for a 30-day comment period.
Comments should be mailed by July 20, 1998, to: District Engineer, U.S. Army Corps of Engineers District, Portland, Attn: CENWP-PE-E, P.O. Box 2946, Portland, Oregon 97208-2946. Copies of the DMMS and SEIS are available for review by calling the Corps' environmental coordinator, Steve Stevens, at (503) 808-4768, or Study Manager Jon Gornick, at (503) 808-4341. All comments received during the public review period will be considered in the final decision, Stevens said.
The report explains the proposed 20-year management plan for the volume of material likely to be removed during routine maintenance dredging from the 40-foot navigation channel. The area addressed encompasses the 103.5 mile stretch of the channel from the mouth of the Columbia River to the Port of Vancouver upper turning basin, and the 11.6 miles of channel from the mouth of the Willamette River to the grain terminal at the Broadway Bridge, Stevens said.
The alternatives considered in the DMMS include: Alternative 1, "no action," which reflects the minimum disposal site requirements to continue current dredging and disposal practices on the Columbia River; Alternative 2, "least cost plan," which minimizes the overall cost of maintaining the channel; Alternative 3, "operational plan," which is a variation of the no action plan and provides additional disposal sites to allow more flexible disposal operations; and Alternative 4, the "proposed plan," which is a composite of alternatives 2 and 3 and expands the least cost plan to provide capabilities for periodic pipeline dredging and upland disposal in areas currently maintained by hopper dredge.
The DMMS includes an assessment of potential beneficial uses of dredged material for meeting non-navigation objectives, including fish and wildlife habitat restoration, industrial/commercial development and recreation.
Major issues addressed in the SEIS, which were identified through a formal public scoping process, include changes in river hydraulics and sedimentation, sediment quality, impacts to fisheries, impacts to riparian habitat and wildlife, and impacts to threatened and endangered species, particularly salmon. No threatened or endangered species would likely be affected by the preferred plan, Stevens said.
The Columbia River navigation project was originally authorized in 1878, with a 20-foot minimum depth. The navigation depth was increased to 25 feet in 1899 and the channel increased to 30 feet deep by 300 feet wide in 1912. Between 1930 and 1955, the navigation channel was increased again to 35 feet deep by 500 feet wide. The current 40-foot by 600-foot channel was authorized in 1962 and completed in 1976. This channel has been maintained through a combination of dredging and hydraulic control works, such as pile dikes.
Local sponsors for the existing 40-foot navigation channel include the Port of Portland in Oregon, and the ports of Vancouver, Woodland, Kalama and Longview in Washington. The state of Washington, acting through its Department of Natural Resources and Wahkiakum County, also sponsors the existing channel.