Winter Weather Events and Preparation

Our Public Works Department diligently follows weather reports, monitors local weather stations and road conditions, prepares for, and is ready to respond to winter weather events.

For the most up-to-date information, visit our winter weather alerts page or follow our social media accounts. 

Watch this video to learn how our Public Works staff prepares for the winter season and weather events:

The City’s main goals in responding to a winter weather event include:

• Clearing Emergency Transportation Routes (ETRs) and ensuring continuous 24/7 police, fire, and emergency medical access to neighborhoods, businesses, and critical facilities.
• Reducing life-threatening and injury-producing conditions on Lake Oswego’s roadways caused by winter weather.
• Reducing the interruption that winter weather may have on the economic, social, and civic life of Lake Oswego community

Plowing, Sanding, and Anti-Ice Route Priorities

Lake Oswego has many hills and streets that are typically the first to get slippery or impacted by snow. Before a snow or ice event, Public Works proactively sands roads or applies anti-icer. During an event, Public Works clears and maintains roads by plowing and applying sand/gravel.

Roads are maintained by the following priority levels:

• Priority One: Arterials and major collectors with moderate to high volumes of traffic e.g. A Avenue, Boones Ferry Road, Country Club Road, Kruse Way, Iron Mountain Boulevard, McVey Avenue, South Shore Boulevard, Stafford Road;  
• Priority Two: Major collectors with moderate volumes of traffic and key steep roads in residential areas e.g. Bryant Road, Kerr Parkway, Royce Way, Overlook Drive, Greentree Road, Foothills Road;
• Priority Three: Minor collectors and residential/neighborhood streets with moderate to low volumes of traffic;
• Priority Four: Residential cul-de-sacs and local streets with low volumes of traffic.  

Plowing_Sanding Routes Map - Dec 2021.jpg

Refer to the map attached or above for priority winter plowing/sanding routes. 

Maintaining roadways in adverse winter conditions depends on many factors including:

• Road Functional Class (e.g. arterial/collector/residential street)
• Traffic volumes
• Availability of alternate routes
• Topography (steep grades, sharp curves, intersections)
• Potentially hazardous areas
• Roads with adequate room to turn City equipment around
• Emergency vehicle accessibility
• Equipment and staffing

Regardless of priority, during a winter weather event, Public Works may deem specific roads or road segments unsafe for plowing or other maintenance activities and may close the road until it can be safely plowed/cleared and/or sanded.

Level of Service Commitment – A Passable Road

During a continuous snowfall event, Public Works aims to plow roads so that both driving lanes are passable, but no pavement is necessarily visible (see photo below). Scraping the snow or ice to the bare pavement can erode the pavement quality and damage infrastructure in the roadway like manholes, water valves, and stormwater drains.

Passable Road During Continuous Snowfall.jpg

During a lull in a snowfall event, Public Works aims to plow and groom roads so there is traction and a passable road (see photo below).

Passable Road During Event.jpg

After a snowfall event, Public Works aims to plow both driving lanes to the point where patches of pavement are visible.

Passable Road Post Snowfall.jpg

Anti-Icer (Magnesium Chloride)

Public Works pretreats streets using an anti-icer known as Magnesium Chloride, which lowers the freezing temperature of water to prevent snow and ice from adhering and bonding to the roadway.

The City prefers to use Magnesium Chloride over salt or other anti-icers due to it being less toxic to plant life, and less corrosive to concrete and steel. Liquid Magnesium Chloride is sprayed on to dry pavement prior to freezing temperatures. In order for the treatment to work properly, the road surface must be completely dry for application.

Anti-icing materials will typically be applied only to intersections where vehicle stops are required, and to steep grades, curves and bridges. 

To learn more about magnesium chloride, watch this video.

Sanding & Gravel Material

Before and during a winter weather event, Public Works crews may apply a sand and gravel mixture to the roadways to help provide traction for vehicles. This is applied strategically to avoid high costs/time of cleanup, as when streets are sanded, the sand needs to be removed after the event.

Sanding material is typically cleaned off roads once the snow and ice has melted. Please be patient during the clean-up process, as it can take multiple days to clear all the sand after the event has ended. Streets will be prioritized using the same service priority level established above.

How You Can Prepare for Inclement Weather

• Plan ahead and be prepared. Inclement weather can last a few hours or a few days. It is best to be prepared with stocked food, water, and the necessary equipment ahead of time. Stay up-to-date with weather alerts and forecasts.
• Winterize your house and vehicle. Clear rain gutters. Maintain heating equipment, repair that leaky roof or pipe, and weather strip doors and windows. Buy chains or terrain tires. Practice putting them on in dry weather and carry them in your vehicle. Buy shovels and ice scrapers.
• Bring pets inside and check on your vulnerable neighbors. For resources and warming shelters, visit 211.org
• Avoid travel if you can. Stay off the road if possible. Our Police, Fire, and Public Works teams are out working 24 hours to address emergencies and clear roads during major storms. By staying off the road, our crews can respond and working quickly. Allow our plows, sanding trucks, and other emergency vehicles to get out ahead of you to treat the roads.
• Wait until conditions improve. Allow extra time to reach your destination. Severe winter weather can change quickly and without warning, making travel unpredictable. A single snow, ice storm, or rain storm can impact each neighborhood differently depending on weather patterns, timing, and geography.
• Don’t abandon your vehicle in the roadway. Abandoned cars block our crews and other emergency responders. This creates a more dangerous situation for everyone. If roads are being blocked by a downed tree or unplowed snow, call Lake Oswego Public Works 503-635-0280.
• And if it snows, have fun! Enjoy our winter wonderland. If you go exploring, dress warmly and watch for vehicles. Or stay inside and get cozy!

Winter Driving Tips

• Avoid following snow plows - give them plenty of room and only pass if necessary.
• Reduce your speed and leave extra distance between vehicles.
• Use extra caution on sharp curves and expect longer stopping distances.
• Don’t use cruise control in wet, icy, or snowy weather.
• Make sure your vehicle is clear of snow and ice before driving.
• Carry a shovel and sand or kitty litter for emergency traction help.
• Keep an emergency supply kit in your vehicle that includes a blanket, some food, and water.
• Keep your car’s gas tank full for emergency use and to keep the fuel line from freezing.
• If you're traveling, before you go, visit www.TripCheck.com(link is external) or call 5-1-1 for the latest in road conditions, weather forecast, chain requirements, and incident information. Let someone know your destination, your route, and when you expect to arrive. If your car gets stuck along the way, help can be sent along your predetermined route. Check in when you’ve reached your destination.

Contact Information

For all snow events, downed-trees, or non-emergency weather needs, call Public Works 503-635-0280 between 7AM-4:30PM. For after-hour needs, call Lake Oswego Communications Dispatch on 503-635-0238.

Frequently Asked Questions

Plowing/Sanding/Anti-Icing

How many snow plows and trucks does the City have to respond to a winter weather event?

The City has five snow plows that work around the clock during inclement weather events. The City also has one 12-yard combination sander/anti-icer and plow. Our crews work 12-hour shifts to ensure that roads are being continuously cleared through the day and night.

Why doesn’t the snow plow scrape/remove the snow to the pavement?

During a continuous snowfall event, Public Works aims to plow roads so that both driving lanes are passable, but no pavement is necessarily visible. Scraping the snow or ice to the bare pavement can erode the pavement quality and damage infrastructure in the roadway like manholes, water valves, and stormwater drains.

I am concerned emergency vehicles will not be able to access my house because of the unplowed roads.

All emergency vehicles are equipped with chains and necessary snow equipment. Public Works plows main arterials, major collectors, and priority roads. During winter weather events, Fire, Police and Public Works all work together as first responders. If Fire or Police are unable to access a road, the Public Works team are available to help respond and clear the road.

When will you plow my street? Is there a schedule or priority list?

The City prioritizes main arterials, major collectors, and bus routes. After these streets are sanded and plowed, crews will attempt to clear residential/neighborhood streets if time and conditions permit. 

To view a map of priority winter plowing and sanding routes, click here.

Can I get my street added to a priority list?

No. The City must prioritize the main arterials, major collectors, and bus routes to address the roads most needed for emergency vehicles.

Can you plow my private street? Can you plow my driveway?

No. The City is not responsible for private property.

Who is in charge of plowing Highway 43/State Street and Interstate-5?

Both Highway 43/State Street and Interstate-5 are state-managed highways. Oregon Department of Transportation (ODOT) is responsible for plowing and maintaining the highways. Please contact ODOT at 503-229-5303.

Will the City be clearing sidewalks of snow or ice?

No. Lake Oswego City Code requires property owners to keep sidewalks and the public right-of-way adjoining their property free from ice, snow, rocks, leaves and other debris.

Does the City use an anti-icer to prepare for inclement weather?

Yes, Public Works pretreats streets using an anti-icer known as Magnesium Chloride, which lowers the freezing temperature of water to prevent snow and ice from adhering and bonding to the roadway. It is sprayed on to dry pavement in advance of the storm. Anti-icing materials will typically be applied only to intersections where vehicle stops are required, and to steep grades, curves and bridges.

The City prefers to use Magnesium Chloride over salt or other anti-icers due to it being less toxic to plant life, and less corrosive to concrete and steel.

Why can’t the anti-icer be used during a storm?

Liquid Magnesium Chloride needs to be sprayed on to dry pavement prior to freezing temperatures. In order for the treatment to work properly, the road surface must be completely dry for application.

Does the City use sand?

Before and during a winter weather event, Public Works crews may apply a sand and gravel mixture to the roadways to help provide traction for vehicles. This is applied strategically to avoid high costs/time of cleanup, as when streets are sanded, the sand needs to be removed after the event.

When is the sand/gravel mixture cleared from the roads?

Sanding material is typically cleaned off roads once the snow and ice has melted. Please be patient during the clean-up process, as it can take multiple days to clear all the sand after the event has ended. Streets will be prioritized using the same service priority level established above.

Trees, Downed Power Lines, and Other Debris

A tree has fallen and is completely blocking the road. Who do I call?

Please call Public Works 503-635-0280. The City will clear the road, whether the tree is located in the public right-of-way or private property. The City will typically cut the tree into smaller sections and move it to the side of the road. If the tree is located on private property, the property owner is responsible for clearing the tree sections and debris.

A tree has fallen and is partially blocking the road. Should I call the City?

Please call Public Works 503-635-0280 for any trees blocking the road, completely or partially. If the tree is blocking the road partially, the City will remove the tree from the road. However, if cars are able to pass through the roadway, it will be a secondary priority for Public Works as they will be responding to high priority needs first.

There are electrical wires and downed power lines on my street. Who should I call?

If you come across any incident involving electrical wiring or downed power lines, do not approach or touch the wiring.

• Call Portland General Electric (PGE) immediately 503-464-7777 and 9-1-1.
• Always assume wires are live and are dangerous.
• Do not touch wiring with your hand or an object.
•  Avoid driving over a fallen power line.
• Do not touch trees or any objects touching the lines.
• Use extreme caution.  

My car is stuck in the roadway and is blocking traffic. Who should I call?

If you are in the roadway blocking traffic or in danger, please call Lake Oswego Communications Dispatch 503-635-0238.

My storm drain is flooding, what do I do?

As the snow melts, the water can carry debris and leaves which block storm drains. Please clear storm drains of leaves and snow to allow water to flow. Do not lift or remove the grate. If removing the debris does not alleviate the flooding, please call Public Works on 503-635-0280.