OVERVIEW EXAMPLES OF DESIGN F0R
HIGHWAYS IN THE RIVER ENVIRONMENT
In this chapter, three examples are given illustrating the application of the principles,
methods and concepts of previous chapters to the design of highway encroachments and
crossings in the river environment. The designs encompass the use of geomorphic,
hydrologic and hydraulic principles to design safe and economical crossings that protect,
maintain and restore the river environment. The three-level design procedure discussed in
Chapter 9 is emphasized in these designs.
In the examples, the designs are determined by well-established numerical procedures;
however, they also depend heavily on the judgment of the engineer. The examples should
be read and studied as an illustrative unit and not as designs from which one can choose the
correct prescription for a problem at hand. River problems are much too complex for a
cookbook approach, as is evident from these examples.
10.1 OVERVIEW EXAMPLE 1 - BIJOU CREEK
This example presents a geomorphic, hydrologic, and hydraulic analysis of Bijou Creek, a
tributary to the Narrows Unit near Fort Morgan, Colorado. The proposed location of the Union
Pacific Railroad is approximately 1,500 ft (457 m) north of the creek (Figure 10.1). The
purpose of the analysis is to ensure the safety of the proposed railroad location and to evaluate
river engineering design alternatives. Since the data for this case study are available in
English units, the figures and tables retain English unit notation. SI (metric) units are given
parenthetically in the text for reference.
Figure 10.1. Topographic map of Bijou Creek study area.