Two fatal car crashes in Provo Canyon (U.S. 189) recently have raised the urgent question of how to make the winding road safer. It is imperative that state, local and federal authorities take immediate action to reduce risk on the highway.

The road has been completely remade in recent years. It's smoother and wider, and many safety issues have been addressed. But there is plenty more that can and must be done as traffic continues to increase between Utah Valley and Heber City.

Since 2002, there have been 15 fatalities in the canyon area, and at least eight can be blamed on vehicles veering over the center line or otherwise moving out of their lanes. But normal turning is hazardous in several spots.

In the first fatal crash of 2008, a Provo woman turned left out of Vivian Park to head west. She apparently didn't see an oncoming Ford F-350 pickup. The truck broadsided the car. Two children, 8 and 7, were killed. A large sign a short distance away may have contributed to the accident by blocking her view.

In the second fatality, a car traveling west at night turned left at Squaw Peak Road. An eastbound vehicle T-boned it, killing a BYU student athlete. In this case, the road curves away just west of the accident site. That curve may have contributed to the driver's failure to see oncoming traffic.

These are not wildly improbably accidents. Any ordinary driver can tell you that at several locations in the canyon it's pretty scary getting across or back on the canyon road. Traffic moves fast, and it's almost always coming at you around a curve, through a dip or over a rise. Frequently it is obscured by median barriers that were installed for safety.

The Utah Department of Transportation installed miles of barriers, and they are undoubtedly a good thing. More turning lanes were also added. It is reasonable to think these measures will whittle down the death statistics.

But human beings are not statistics, and this is no time for complacency even if the road is safer now than it once was. The goal of the American Traffic Safety Services Association is "zero deaths," and that should be the goal of local highway agencies as well.

The Wasatch Front seems destined to keep growing, and U.S. 189 will eventually be four lanes to Heber City. Most of the danger, however, lies not in driving the distance but in turning on, off and across the highway at four trouble spots -- the Sundance turnoff, Vivian Park, Nunns Park and Squaw Peak Road.

You don't have to be a highway engineer to see this, nor do you have to spend large sums on traffic studies. You just have to open your eyes.

UDOT should take two common sense steps right now.

• First, remove the vision-obstructing sign near Vivian Park. It partially blocks the view of oncoming vehicles just as they emerge from a slight incline in the road. Taking the sign down would make that intersection a wee bit safer. A smaller sign at a different spot would do the job as well.

• Second, reduce the speed limit by 20 mph from a quarter mile above the Sundance turnoff to some distance below Vivian Park. Do the same at Nunns Park, and again at the Squaw Peak Road. Don't just throw up some speed limit signs but install some big flashing yellow lights to wake up drivers and compel attention.

For a few extra bucks a new technology can help. A Midvale company, InterPlan Co., early this year presented UDOT with a study of effective electronic speed limit signs. The signs can display speed limits that can be adjusted remotely, depending on conditions.

Variable speed limits are actually quite common in Utah. Just travel U.S. 89, for example, through communities like Centerfield, Marysvale, Circleville, Orderville and you'll find yourself frequently slowing and then accelerating after you're beyond town.

The same principle should apply at the Provo Canyon trouble spots.

Sure, there are some complications for traffic engineers, but we see nothing that appears insurmountable. Take the left turn onto Squaw Peak Road, where a life was lost recently. There's no question that it's nerve-wracking to be sitting there waiting to make a left with cars coming around a bend just ahead. The solution might be to simply prohibit turns and instead provide a safe U-turn somewhere else -- say at Canyon Glen. Likewise, traffic entering Provo Canyon from Squaw Peak Road might be directed up to a safer turnaround at Nunns Park. You get the picture.

Most troubling is the Sundance turnoff. If you've ever turned east toward Heber from Sundance, you know the meaning of fear. Fast-moving cars suddenly appear from behind a cliff. Anyone making that maneuver had better have plenty of horses under the hood. A reduced speed limit in that vicinity would dramatically enhance safety until the inevitable day that a stoplight is installed.

Of course, traffic professionals have far better access to ideas and resources than the Herald's editorial board. But our members drive the road frequently, along with tens of thousands of our neighbors. We urge UDOT to move forward without delay.

Other authorities can help too. The Utah Highway Patrol, for instance, could increase enforcement in the trouble zones.

There's no time to lose. Lives are at stake. The Fourth of July seems to be cursed. Including accidents on the University Avenue stretch, U.S. 189 has seen four fatalities on or around the Fourth since 2002. All this summer, various hikers, boaters, sightseers and picnickers will be swarming up and down the canyon. We don't want to see a tragic replay of recent history.

Do you agree?