Drive/East Road Study: Priorities
Evaluation of a roadway design must be based on a set of priorities and criteria.
I hold a strongly utilitarian view of streets and roads, so I think of streets
and roads as having major and minor design goals. The priorities will differ
from one street to another, depending on many factors.
NM 502 is an artery. It is one of only two public routes that
lead from Los Alamos to Santa Fe, I25, and Albuquerque. NM502 serves several
thousand commuters who live outside the townsite and work for Los Alamos National
Laboratory and other local employers. NM502 serves through-traffic as a business-district
bypass. It is a core element in emergency transportation. The corridor under
study here is the only paved evacuation route from the Townsite that does not
require crossing Omega Bridge. It is the most direct route away from the surrounding
mountains and forests for most of the town's residents, and played a vital evacuation
role in the evacuation forced by the Cerro Grand Fire.
These functional goals lead to my version of the priorities for the NM502 corridor
|Highest priority: move motor vehicle traffic
|Lower priorities: everything else
- Comfort and convenience
- Other transit modes
- Environmental features
To evaluate actual or design performance, small changes in the high priority
features must be weighed against large changes in the less important matters.
Of course, there are a few cases where one can have the best of all worlds;
but more frequently, trade-offs are necessary. Perhaps thinking in terms of
the "greatest good for the greatest number" is a reasonable
qualitative approach. Thus, a small change in efficiency that affects thousands
of users could weigh heavily against a large change in efficiency for a small
number of users. Another viewpoint should be considered: "What's the
worst that can happen?" For example, a small potential for a serious
consequence must sometimes be weighed against a high probability but modest