Flood-Control Project for Northwest Branch, Anacostia River, District of Columbia and Maryland: Hydraulic Model Investigation
Abstract
A 1:30-scale model was used to study flood-control plans for a reach of the Northwest Branch of the Anacostia River near its junction with the Northeast Branch. Plans for this reach included the construction of a section of high-velocity concrete channel 550 ft long to pass flood waters safely through two existing bridges and preclude the need for their reconstruction. The reach in question is subject to tidal effects as well as backwater effects from the Northeast Branch. The purposes of the model study were to check the adequacy of the proposed improvement plan, which had been designed on the basis of hydraulic computations, and to develop such modifications as might be found desirable. The fixed-bed model reproduced the concrete channel with bridges and about 1600 ft of the channel and floodway upstream and downstream therefrom. It was determined from the investigation that the proposed design would result in unstable flow below the Baltimore and Ohio Railroad bridge within the high-velocity channel, and that the hydraulic jump would not be retained on the paved section at the end of the high-velocity channel for all tailwater conditions. Satisfactory modifications developed during the model study included a decrease in the floodway width upstream of the paved channel, superelevation of the, channel floor within the curve of the high-velocity channel, and changes in the alignment of side-wall transitions.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1956
- Accession Number
- ADA637662