Portland is beefing up its storm arsenal in an effort to avoid a repeat of last winter, when snow and ice throttled the city for days at a time.

The new plan includes more widespread use of road salt, which city transportation officials had until last winter rejected as too environmentally hazardous.

The city's transportation bureau is buying six new salt spreaders that can be installed on city trucks, and it's turning to other bureaus and private businesses to get more crews out clearing roads.

"I think we're much better prepared," said Commissioner Dan Saltzman, who oversees the transportation bureau. "We've learned a lot of lessons from the last winter."

The new investment falls short of the $1.2 million in new equipment Saltzman and the transportation bureau had sought in the latest city budget.

And the city will still rely on rising temperatures and traffic to clear ice and snow off the many roads and side streets it doesn't plow at all. It will also count on Mother Nature to clear the last vestiges from the roads it does plow, because plows intentionally leave up to half an inch of snow or ice in place.

Portland's moderate climate usually comes through. But when it doesn't, it can cost the city in productivity.

Last winter, Portland Public Schools lost nine days of school due to snow. Businesses, too, were closed for days at a time, and hourly workers lost wages. Mayor Ted Wheeler asked landlords to waive late-rent fees in the wake of the storm.

That was an exceptional winter for Portland. But some forecasts call for a similarly fierce, snowy season ahead thanks to the influence La Nina, a pattern of atmospheric and oceanic cooling.

This year, the city will keep 300 tons of salt on hand, enough to treat between 2,000 and 3,000 lane-miles of roadway. It can also procure and store another 1,000 tons of salt ahead of a big storm.

Portland will still try to limit its use of road salt to a handful of roads that are routinely rendered impassable in snow, and where runoff won't send salt into rivers and streams. But in severe storms, the city will consider more widespread use, Saltzman said.

The city transportation bureau will also draft drivers and trucks from the city water bureau during storms, and it will hire private contractors to supplement city plows. And it will potentially call on Seattle to send aid, and return the favor if that city is socked in.

As in later storms last season, the city will assign police to enforce tire-chain orders, keeping drivers from trying their luck on hills and getting stuck, blocking traffic and snowplows in the process.

And it will offer parking meter amnesty when storms hit to encourage drivers to take transit rather than risking a trip in their private vehicle.

Saltzman previously sought $1.2 million to buy new snow-clearing equipment and $1.6 million a year to beef up PBOT's weather-response staff and materials.

Instead, the bureau got $30,000 for the new salt-spreaders, and the city set aside $300,000 in contingency funds to pay for any unforeseen snow removal costs.

"If we do see a major snow or ice event on the level of last year, I won't be hesitant to ask for more money," Saltzman said.

After January's storms, Wheeler, then just two weeks in office, said the city didn't do enough to keep roads clear and commerce flowing.

"I think the public can expect to see a marked improvement this year from last year," his spokesman, Michael Cox, said Monday. "Last year we faced an unprecedented series of winter weather events. We learned a lot of lessons and we believe those lessons have been applied to our planning this year.

He said the mayor would also announce plans to address concerns about housing and emergency shelter available during severe winter storms. At least four homeless people died of exposure last winter.

Certain limitations of the city's snow-removal plan won't change.

The city will still only plow roughly a third of its roadways, with a focus on public transit and emergency routes. Starting this year, however, it will include key school routes and the central business district -- where heavy traffic was previously thought sufficient to keep roads clear -- in an effort to avoid a citywide shutdown like last winter.

The city will also keep its goal of achieving "passable" roads that are navigable for vehicles with front-wheel drive or traction devices on their tires.

Portland city plows leave up to half an inch of snow on the road, relying on chemical deicer, the weight of passing vehicles and improving weather to remove the rest. Portland officials say that avoids damage to plow blades or the roads surface, and therefore repair costs when the snow season ends.

But that's an uncommon practice in areas more practiced in snow removal, and with more funding dedicated to that work.

Cities in the nation's Midwestern "snow belt," for example, set target times to achieve bare and wet pavement after snowfall. Seattle, too, tries to reach that standard within 12 hours after a lull in the storm.

Portland can't be compared to those areas because of the tendency for temperatures to hover near the freezing point, said Peter Wojcicki, the transportation bureau's street system division manager.

Last year's storm was complicated by a short thaw followed by a days-long deep-freeze that turned packed snow into a sheet of ice that plows can't remove. Those freeze-thaw cycles are less common elsewhere, Wojcicki said.

He also pointed out that Portland has challenging terrain than many cities that regularly deal with heavy snow.

Even with its conservative approach to plowing, Portland still incurred significant road-repair costs after the last winter storm season. The transportation bureau in the spring identified more than 1,000 potholes left behind after the snow and ice storms and made worse by drivers' use of tire studs and chains.

The city temporarily quadrupled the number of road crews typically assigned to pothole repair to address the backlog in what it called a "Patch-a-Thon."

Where Portland will use road salt

Portland officials say they'll focus their use of road salt on key routes, including:

* West Burnside Avenue

* Sam Jackson Park Road

* Terwilliger Boulevard

* Skyline Boulevard

* Germantown Road

* Southeast 112th and Mt. Scott Boulevard

* North Going Street

-- Elliot Njus

enjus@oregonian.com

503-294-5034

@enjus