Flood Control and Sediment Studies

           

The Guadalupe River study area is located in San Jose, California immediately south of San Francisco Bay. As part of a redevelopment plan, the Corps of Engineers is designing and cost sharing for channel improvements on the Guadalupe River to provide for 100-year flood protection. Much of the channel reach upstream of Los Gatos Creek was model studied at ERDC (formerly Waterways Experiment Station, WES) in 1988 as part of the General Design Memorandum (GDM) studies conducted by Sacramento District. After that modeling there were modifications of the flow split between the box culvert and natural channel at the I-280 over-crossing, and modifications to the channel to incorporate aesthetic and architectural treatments. The revised intake design for the box culvert at I-280 was model studied at ERDC beginning in 1992 at a 1:25 scale. The USU study, initiated in 2000, established the current design configuration from upstream of Santa Clara Street to downstream of Coleman Avenue.

         

Physical model study of the proposed Double Box bypass Culverts of the Guadalupe River and Los Gatos Creek from Santa Clara Street to Coleman Avenue in San Jose California.


          

The purpose of the study was to investigate the impact of additional highway piers or columns from the proposed State Route (SR) 87 High Occupancy Vehicle (HOV) Lane Widening Project on the flood of the Guadalupe River. In particular the impact on the floodway and river channel was studied at the San Fernando Street bridge, Park Avenue Bridge, and the planned Woz Way culvert and outlet to be located just upstream of San Fernando Street. The concern is that the additional bridge columns required to accommodate the widening of the Guadalupe River Viaduct structure could cause the pressurization of the Park Avenue bridge, San Fernando Street Bridge, or the Woz Way culvert.

The project consisted of a physical model study of a new curved ogee spillway for Success Dam and Lake, located on the Tule River in the Sierra Nevada foothills, 8 miles east of Porterville, California.  The new spillway, a curved ogee spillway, will raise the elevation of the reservoir by 10 feet.  The curved ogee spillway must pass the Probable Maximum Flood (PMF) without exceeding a maximum reservoir elevation to provide adequate freeboard below the top of the dam.  The model is a 1:25 Froude scale model constructed of mortar.  The curved ogee crest is innovative in that it will pass more flow than a conventional straight ogee crest.  Other design considerations included the application of the curved ogee in a narrow bypass channel with non uniform approach conditions and velocities.  Downstream tailwater effects were a concern for the stability of the flow over and downstream of the crest.  An under-designed crest shape was also tested to determine if the geometry of the crest would increase flow capacity without producing negative pressures.

The purpose of the Labyrinth Weir model was to address the design, construction, and the operation concerns of the U.S. Army Engineers, Sacramento District (CESPK-ED-D); Hydroplus Inc.; the City of Visalia, California; the Division of Flood Management and the Division of Safety of Dams of the California Department of Water Resources (DWR); the Reclamation Board of the State of California; the California Division of Safety of Dams (DSOD); and the Kaweah Delta Water Conservation District.

 

 

 

A Diversion Structure has been proposed for flood control on Mill Creek in Salt Lake County, Utah. The structure will be located at Highland Drive, and will divert excess flow from Mill Creek into the Hillview Detention basin. The structure will be designed to divert excess flows  from a 100-year thunderstorm. The maximum flow  will be split into a  culvert flow to Mill Creek and a diversion pipe flow.  The structure will have to either transport the sediment loads back to the downstream Mill Creek channel or will have to store the sediment loads.  The structure will provide a sediment basin for storage of excess bed loads that can not be transported by the return flows to Mill Creek, and the structure will also have to prevent sediment from being carried by the diversion pipe flows.

 

A Diversion Structure has been proposed for flood control on Mill Creek in Salt Lake County, Utah. The structure will be located at Highland Drive, and will divert excess flow from Mill Creek into the Hillview Detention basin. The structure will be designed to divert excess flows  from a 100-year thunderstorm. The maximum flow  will be split into a  culvert flow to Mill Creek and a diversion pipe flow.  The structure will have to either transport the sediment loads back to the downstream Mill Creek channel or will have to store the sediment loads.  The structure will provide a sediment basin for storage of excess bed loads that can not be transported by the return flows to Mill Creek, and the structure will also have to prevent sediment from being carried by the diversion pipe flows.