McNary Dam Columbia River, Oregon and Washington. Second-Step Cofferdam Closure. Hydraulic Model Investigation.
Abstract
The closure of the second-step cofferdam at McNary Dam was accomplished by depositing in a gap in the upstream leg of the cofferdam sufficient 12-ton concrete tetrahedrones to divert the bulk of the river flow through the partially-completed spillway and to allow subsequent placement of small materials to seal the gap. The model studies that led to the successful closure of this cofferdam were unique in nature and, by establishing the merits (and limitations) of the several models, may serve as an excellent guide for studies of similarly executed closures.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1956
- Accession Number
- ADA000408