  This paper addresses the problem of finding multiple near-optimal,
spatially-dissimilar paths that can be considered as alternatives in the
decision making process, for finding optimal corridors in which to construct a
new road. We further consider combinations of techniques for reducing the costs
associated with the computation and increasing the accuracy of the cost
formulation. Numerical results for five algorithms to solve the dissimilar
multipath problem show that a "bidirectional approach" yields the fastest
running times and the most robust algorithm. Further modifications of the
algorithms to reduce the running time were tested and it is shown that running
time can be reduced by an average of 56 percent without compromising the
quality of the results.
