As flat, plain, and old-fashioned as the title: the novelized building of a big suspension bridge across the Tano Gorge, 75 miles north of Santa Fe, N.M.--complete with technical problems, political pressures, corporate hangups, and a smidgin of drab romance. The major obstacle to the Big Bridge, as troubleshooter Sam Taylor (from Ross Associates construction firm in San Francisco) soon learns, is the high wind in the gorge. But other troubles soon crop up as Sam hangs around the building site: employee accidents; the somewhat shady, distinctly lecherous governor is out to capitalize on the construction; the Chicano community is up in arms when an all-Anglo work force is recruited--and even more so when a Chicano lad dies in a bridge fall; a scurrilous land speculator is trying to make the most of the situation; and there are questions of command--both on the site (Sam has to dismiss the supervisor) and back home in Frisco (old man Ross has a stroke, Sam tries to take over). Plus: Stern tries, mostly in vain, to stir up some excitement about the two, conflicting loves in Sam's life: city girl Liz and country girl Ellie (daughter of the county's richest landowner--a fine, crippled gent who does his best to balance all the money/politics interests). In slow, stiff dialogue scenes, then, Sam deals with all these threats to the bridge--which, perhaps, should never have been started in the first place (those wind dangers). But finally the towers are up, the cantilevers are in place . . . when a tornado arises, promising a little action at last. (Very little is actually delivered.) Waxworks characters, minimal suspense, and a plodding pace--but some readers may appreciate the techno-talk (""By how much would cable stays increase resistance to wind-caused oscillations?""), the earnest man-to-man camaraderie, and Stem's familiar, stolid craftsmanship.