I love Waze. Absolutely love it.

It’s a great traffic app for alerting drivers to everything from a major crash ahead to a guy fixing a flat on the shoulder to road crews trimming weeds. Just punch a destination into your smartphone and a Siri-like voice tells you how to skirt traffic slowdowns.

But not everyone shares my passion.

Many residents and traffic engineers are fed up with Waze for diverting untold numbers of commuters onto streets they say were once fairly free of traffic. The complaints come from side roads feeding off Interstate 680 at the Sunol Grade, residential areas near the Highway 92-U.S. 101 interchange on the Peninsula, city streets in Mountain View and Los Gatos.

Waze, whose navigation advice is based on GPS tracking and crowdsourced feedback both from the Waze app and Google maps, issues 1.2 million road alerts each month. That’s a tally sure to grow, which makes Rose Morgan, of Mountain View, shudder.

“My neighborhood is pretty much up in arms about the huge influx of cars trying to avoid freeway tie-ups and cutting between 280, 85 and 237,” said Morgan, who lives on Cuesta Drive near El Camino Hospital.

“We have seen drivers running a red light at a school crossing, passing in a double yellow turn-only lane, honking and harassing local drivers who drive at the speed limit. Lately, we’ve seen huge tour buses careening along at 50 mph as well. At commute hours, it takes up to 20 minutes just to get out of one’s own driveway.”

Highway 9 from Los Gatos to Cupertino has seen a surge in traffic as morning commuters try to escape the Highway 85 jam by taking Highway 17 south to 9 at Waze’s urging. And 101 at Highway 92 may also be suffering from a Waze overload.

“Waze and other such apps have done more to damage traffic flow than the booming economy,” insists Larry Blair, who lives near the interchange in Foster City. “When traffic for the San Mateo Bridge slows down, Waze instructs drivers to get off the freeway. The result is gridlock in our neighborhood.”

But the East Bay may have the biggest Waze worry. The evening commute on 680 north from Milpitas to Pleasanton and beyond has been horrendous for two decades. Now attempts to use Mission Boulevard and Calaveras Road to skirt the freeway have led to more vehicles testing those narrow alternates.

Recently big rigs have gotten stuck trying to bypass 680 by using narrow Morrison Canyon Road where trucks are banned.

“This is forcing drivers using Waze-type services to move to inner roads, especially Paseo Padre Parkway, from 5 to 8 in the evenings,” said Stawan Kadepurkar of Fremont. “For residents like us to even cross or turning on to Paseo Padre from roads such as Upland, Pine Street or Cam Del Campo is very difficult. This has been the situation for almost a year now with residents very frustrated.”

And engineers as well.

“This is just another example of the negative impact to our quality of life of the non-commuters caused by Google Maps and Waze,” said Fremont traffic engineer Norm Hughes. “In years past, this was a known shortcut by a few drivers but it has become really intrusive and a safety concern for others on the road.”

OK, points made. But they have not dimmed my love for Waze. For some of us, it’s taken a huge chunk of stress out of being on the road. Why is traffic slow? How can I get around it? Waze tells me.

Google owns Waze, which was first developed in Israel, and spokesperson Julie Moosler says it “can help spread traffic across the grid of open space on the road and help prevent mass congestion.”

CHP officer Art Montiel agrees. “I feel it would be the same as if we notify motorists about a crash on the freeway and ask them to avoid the area and take alternate routes.”

Matt Morley, the public works director in Los Gatos, sees problems as well as benefits. His town endured Waze-induced clogged streets last summer as drivers tried to avoid Highway 17 to get to the beach.

But, he conceded, “Waze provides information that commuters value.”

Value indeed. Although naysayers are vocal, Waze fans like Tony DiBenedetto of San Jose are also numerous.

“I’Il often fire it up just before leaving to see which of several routes to my destination is the best rather than to just go the same way I’m used to going. Fewer surprises that way.”

But there was one surprise on a trip to Mendocino. Out in the middle of nowhere on Highway 128 he got a warning he hadn’t heard before. Roadkill ahead!

“I laughed, but sure enough,” he said, a smooshed critter “was there when I rounded the bend about a quarter of a mile ahead.”

Chalk up another one for Waze.

Follow Gary Richards at Twitter.com/mrroadshow, look for him at Facebook.com/mr.roadshow or contact him at mrroadshow@mercurynews.com.