WASILLA -- Look out Juneau.

Wasilla could become Alaska's third-largest city under the most sweeping of several annexation proposals before city officials.

Under the broadest, the city would more than double to 16,000-plus residents, and expand from a little more than 13 square miles to 31, according to city estimates.

The "new" city would encompass a diverse area from Seward-Meridian Parkway -- including dense subdivisions around Bogard Road -- to about five miles up booming Knik-Goose Bay Road, north to Seldon Road and south to the rural farmlands of Fairview Loop Road.

Last February the city looked at expanding its eastern boundary from Peck Street to Seward-Meridian Parkway. But then more people from other areas came forward requesting city services as well, said Wasilla Mayor Verne Rupright.

Now the City Council is weighing whether to stick with the February proposal, add in additional areas individually or add all of them over time.

The council is expected to make a decision next spring, after public hearings, though the entire process could take about two years. The state Boundary Commission would need to approve any annexation.

The City Council's decision will be based, in part, on a cost-benefit analysis in the works -- how much money would the city make from new sales tax revenues versus how much more will it cost to police, plow and otherwise serve residents across a wider area.

As a bigger city, Wasilla would get a larger share of federal and state revenue sharing, Rupright said. "That brings more into the economy and more growth."

The prospect of bringing city controls to Wasilla's frontier fringes has some potential city residents wondering. What happens to farms? What about four-wheeling trails? Will I have to pay the city for services I already have?

"I'm not going to be hooked up to sewer, I'm not going to be hooked up to city water in my lifetime," said Paul Skvorc, a fish-tracking scientist who's lived off Fairview Loop for nearly 20 years. "Other than that, I don't know what services they would provide to me."

Rupright said he would hope to pay for increased cost of services like road maintenance with increased sales tax revenues from businesses annexed into the city.

Until a cost-benefit analysis is complete, however, it's unclear whether sales taxes will make up the difference.

According to previous reports, a study of February's smaller annexation found it could cost $420,000 to patrol the additional area plus take care of roads, while businesses located within the new boundaries would only add $185,000 in sales tax revenues.

If annexed, residents like Skvorc would pay reduced borough property taxes because they would no longer have to pay for road-service areas, city and borough officials said. There is no city property tax in Wasilla.

The city also couldn't bring water or sewer to new areas without residents voting to form a local improvement district, Rupright said. As for farm concerns, the mayor himself has a goat, a stable mate for the steers he once kept at his home. He said farms will be zoned rural residential and can operate as usual.

Fans of four-wheelers, though, may be in for some changes.

Wasilla's residents often see off-road vehicles revving down bike paths, through parks, sometimes even past City Hall.

Annexation could expand the city's recent crackdown on rogue off-roaders to "problem areas" north of town, Rupright said.

So far this year, the city's new vigilance has resulted in one felony and several misdemeanor arrests, more than 50 tickets and six seized vehicles, the mayor said.

"It seemed to get them out of the parks and off the sidewalks to a degree."

If the largest annexation area is approved, the new city would take in the Williwaw subdivision off Bogard Road and Via Tranquilla Drive off Wasilla-Fishhook Road, fairly dense neighborhoods that get their share of police calls.

Right now the Alaska State Troopers -- sometimes with help from Wasilla police -- handle trouble calls. Wasilla police would get them if the largest annexation goes through.

The city police department would need three more officers and probably two more patrol cars just to meet the needs of February's smaller annexation proposal, said acting Chief Craig Robinson.

Now the department is conducting a study with the troopers to find out how much busier officers could be if the new annexations happen, and how much the city might have to spend.

"It is all the bottom line: What does it cost and what's the return," Robinson said.