REDINGTON, Ariz. (AP) -- The sign on the dusty road running past Andy Smallhouse's cattle ranch reads "No Pavement 50 Miles" and he would rather it stay that way, especially since the alternative could be a freeway.

The biggest road in the area now is Interstate 10, about 40 miles away. But state planners are drawing lines on a map and some of those would route a proposed I-10 bypass right through the southern Arizona ranch.

"We don't see any way possible for an interstate to come through the middle of us and not interrupt what we're doing," said Smallhouse, whose great-great-grandfather first established the ranch in 1884. "We might possibly profit from it but we're not really interested in that aspect."

The idea for a bypass is to create a new route for cross-country truckers and long-distance motorists so that traffic can skirt Tucson, a metro area of 1 million. Further north and west, another part of the bypass is contemplated to route I-10 traffic around even bigger and even more congested Phoenix.

The proposals are an outgrowth of ongoing efforts to adjust to Arizona's furious growth. Arizona and Phoenix consistently rank among the nation's fastest-growing areas and traffic congestion has been a byproduct, even on the interstates.

The roughly 100-mile trip from Tucson to Phoenix can easily stretch to three hours because of bottlenecks that slow motorists to a crawl at both ends. That often gives road trips the feel of rush-hour commutes.

Trying to create an alternative has set the stage for conflicts, and not just around Smallhouse's ranch. Similar growth-vs.-environment concerns are likely to surface with a separate state study of a possible alternate to complement Interstate 17, a 145-mile highway often jammed with Phoenix-area residents escaping the desert heat by heading to northern Arizona's cooler high country.

On the Interstate 10 proposals, some of the possible bypass routes under study would cross miles of table-flat desert of no particular distinction. Others, however, would put concrete in remote areas near national monuments, wilderness areas and other largely undeveloped places.

Those include the lower San Pedro River valley, where the washboard road runs past Smallhouse's place. The north-flowing San Pedro is lined by cottonwoods and at places flows next to steep bluffs and vertical stone cliffs. Its aboveground flow is intermittent but it is one of Arizona's few undammed rivers.

Residents delight in talking about regularly seeing javelinas, mountain lions and other wildlife in the area.

"We have a beaver dam and it's so unique in that you look around and you have desert," said Maria Araiza Troutner, who lives about a dozen miles south of Redington in Cascabel and is active in an anti-bypass group.

State transportation officials acknowledge the possible I-10 bypass routes raise environmental concerns and other objections. But they say no decisions have been made and the routes under study avoid designated wildernesses and other protected areas.

"We have done due diligence in identifying the environmentally sensitive lands and the sensitive land use areas and have sought to not traverse them," said Dale Buskirk, the Arizona Department of Transportation's planning director.

In areas where there are concerns, the highway could be designed with wildlife crossings but without exits or entrances in sensitive areas, Buskirk said.

And the state can't ignore that its population and traffic are growing and that I-10 can't handle the load, said S.I. Schorr, a Tucson real-estate lawyer and state Transportation Board member who first requested the I-10 bypass study.

"The growth is going to occur irrespective of whether we plan for these roads or not," Schorr said. "It's simply a question of planning for the growth."

The Department of Transportation held public hearings on the results of its preliminary study, and the Transportation Board could decide as early as Dec. 21 whether to order more detailed work.

Buskirk said rough cost estimates on a 25-mile bypass for I-10 are $6 billion to $8 billion and so far there's no funding identified.

But the state's draft study says building a bypass as a toll road is a possibility, and a conservationist noted that top state officials and others are talking about launching a new statewide transportation initiative.

"Now is the time to have this conversation. We take this very seriously," said Tom Collazo, the Nature Conservancy's Arizona associate state director for conservation. "Preliminary plans lead to plans and plans lead to action eventually."

The conservation group has registered strong concerns about the bypass project in general and about routes proposed for the San Pedro River valley and the neighboring Aravaipa Valley to the east.

Private and governmental organizations have spent $25 million to buy or protect approximately 40,000 acres in the San Pedro River valley, and the two valleys represent important opportunities to preserve open space, wildlife corridors and habitat for endangered native species, Collazo said.

"We are a growing state and we do need to be thoughtful about how and where that growth occurs," he said.

Back at their southern Arizona ranch, Andy Smallhouse and his wife, Stefanie, also are thinking long-term, wondering whether the products of generations of work will still be around for the next generation.

Even if it takes the state 20 years to build the bypass, "20 years in a 120-year history is nothing," said Stefanie Smallhouse.

"Basically this heritage would come to an end and that would be just at the time when my daughter and my son would be deciding whether they wanted to take over the ranch. And so to me personally, it's hard to talk about," she said, dabbing an eye. "As far as the future, it's (not) just a chapter in the heritage of the ranch. It could be the end."

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