NM502/Trinity 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 under consideration:

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 inconvenience.