Gutter Flow and Inlet Spacing
When stormwater is collected and carried along the roadside in a gutter, or next to a curb or barrier, the […]
Bridge Deck and Downstream End Drainage
The drainage design for the bridge deck requires the coordination of the bridge designer, the State Hydraulics Office, and the
Introduction to Drainage of Highway Pavements
Roadway and structure pavement drainage should be considered early in a project design, while the roadway geometry is still being
Placement of Rock Bank Protection
Once the type of rock has been selected from Table 4-2, the next step is to determine the appropriate installation.
Countermeasures for Stream Instability
Because of the abundance of watercourses in Washington State, and the legacy of highway placement along and across their corridors,
Manning’s Roughness Coefficients (n)
Table 4-1 presents references for Manning’s roughness coefficients. Table 4-2 presents estimated Manning’s roughness coefficients (n) for quarry spalls and
Critical Depth of Open-Channel Flow
Before finalizing a channel design, the hydraulic designer must verify that the normal depth of a channel is either greater
Roadside Ditch Design Criteria
Roadside ditches are generally located alongside uncurbed roadways with the primary purpose of conveying runoff away from the roadway. Ditches
Field Slope Measurements
The slope is calculated by dividing the vertical drop in the river channel by the horizontal distance measured along the