Portland is located at the northern end of the Willamette Valley, a rich and diverse agricultural region.  The long growing season and mild temperatures of the Willamette Valley are favorable for a diversity of agricultural products.  Due to the high ground water level, irrigation is widely used to raise cannery crops, berries, grass seed, and pastures.

City Layout - Four Quads

For a city that's split by a river, Portland is surprisingly easy to navigate by car, bicycle, or foot.  The exception is traversing the West Hills as many of the streets curve and wind.  The town is laid out in quadrants--north and south are divided by Burnside Street: east and west, by the Willamette River, which features a network of ten breathtaking bridges. You can get a good picture by viewing a Portland street map or try the Metro Quad map.

Hills in the West
Flat Land in the East

Looking east from downtown Portland (20 feet above sea level) you immediately notice Mt. Hood (11,235 feet - about 40 miles from downtown), the Cascade Mountain Range, and the flat landscape of the east side across from the Willamette River.

Looking west you notice the hills and some of the houses - those not covered up by the greenery - that dominate the view.  You imagine yourself in a house looking over the city and the mountains.  Explore the east side more and you will encounter hilly terrain in certain neighborhoods like Mt. Tabor.  Traveling south into Lake Oswego and West Linn, you also get into the hills.

Traveling west over the ridge of hills on the west side, you dip into a flat valley.  Once in the Tualatin plains, looking west, your eyes will meet a gentle rising group of hills called the Coastal Mountain Range. The plains lay in the Hillsboro-Forest Grove-North Plains-Banks area of Washington County.  The plains were once the most important agricultural district in the circle around Portland.  In the 1830s Hudson' Bay Company employees from Fort Vancouver sometimes drove cattle over the muddy passes of the West Hills to fatten on summer grasses of the Valley.  In the 1840s American wheat farmers pushed aside the British cattle.  Today, the Tualatin Plains is mostly communities and industrial areas but crops still exist in a good share of the plains.

TopoZone will allow you to explore the elevations of Portland.  You will note that within a mile of downtown heading west you are up to 500 feet.  Drive up the winding streets and you will reach heights of over 1,000 feet.

City of Bridges

Portland is often called Bridge Town because ten bridges span the Willamette River.  The bridges of Portland are numerous and diverse.  The structures, ranging in age from 27 years to 90 years of age, represent a variety of construction types including vertical lift spans, double-leaf Bascule drawspans, and the longest tied arch span in the world.  Andrew Hall's Bridge Gallery displays all ten of the bridges on your screen.

The City of Roses becomes the city of bicycles in early August each year as upwards of 12,000 people pulled on brightly colored jerseys, clamped on helmets and grabbed cameras to join in the annual Providence Bridge Pedal.

The event, extraordinary for its route over eight of Portland's Willamette River bridges, draw Oregonians and out-of-towners of all ages.  Children in bike buggies, couples on tandems and adults pedaling everything from sleek titanium racers to one-speed cruisers filled the streets and bridges from early morning until about noon.

Physical Features Impact Daily Living

Natural, physical features and climactic forces have considerable impact on the city, and on living in the city.  Portlanders are rarely troubled by the rain, they appreciate, and delight in sunshine. Newcomers are heard to comment frequently on how green it all is.  On clear days we can see Mt. Hood, Mt. St. Helens, Mt. Adams, and even Mt. Rainer.

West Hill Slides

During the winters of 1996-97, when the Portland area received record rainfall, the West Hills had over 350 slides (the entire metro area had 630 plus slides). The majority of the slides caused minor damages but a few wiped out homes and a some caused structural problems to homes.  Many people were shocked to learn that their standard insurance policy didn't cover slides.

Most slides are small and shallow, the exceptions are undated prehistoric slides under what is now the Oregon Zoo and the Washington Park Rose Garden. 

Because of the '96 slides, the City of Portland requires geotechnical engineers in slide hazard zones to drill soil samples, evaluate the firmness of underlying soils and measure depths to bedrock.  The city requires geotechnical reviews at new building sites or for major remodeling projects, existing homes and buildings do not get the same scrutiny.

As a result of the renewed study, what became better known is that most of the homes in the West Hills are built on glacial loess − windblown glacial particles. The windblown silt ranges from a few feet deep in some places to 100 feet in others over basalt. Although most have survived just fine through decades of Oregon rainstorms, there can still be problems. Portland State Unviersity Bill Burns states that "The particles are not as packed together as they could be, which makes them more moisture sensitive. Combine that with the steep slopes and the risk for landslides goes way up."

Portland State University Study  A comprehensive study by PSU geologists following the 630-some landslides that hit the region after the heavy rains of early 1996 found that "roughly 76 percent ... were linked to poorly planned land-use practices on steep or unstable slopes." They were often triggered by "uncontrolled storm-water runoff coming from roofs and streets that contributed to adjacent slope instability."

State geologists are now mapping the state with LIDAR -- light detection and ranging -- a system that gathers high-resolution images of the surface of the earth. It employs lasers that let scientists see landslides that occurred decades, even centuries, before. State and federal scientists will combine the LIDAR maps with geologic data and records of past landslides to identify levels of hazards throughout Portland.

The U.S. Geological Survey in 2006 also installed monitors at Mount Cavalry Cemetery in Northwest Portland to track rainfall and soil moisture, looking for a correlation between the two. That may allow them to better predict when the conditions are right for slides to occur.

Preventative Steps  Homeowners compound that risk if they let water run off their roofs or lots onto the ground around their home. The most important preventative step is to route runoff away from homes so it doesn't infiltrate the ground and weaken the soil.

Trees

Recognizing that a tree canopy can help combat climate change, and ultimately save society billions of dollars in combination with more conventional "gray" infrastructure, jurisdictions are stepping up to save existing stands and replant trees.

In the summer of 2008, Portland, known nationally for its well-treed image, launched "Grey to Green," a five-year, $50 million, green-up-the-city initiative that includes planting 83,000 trees - 50,000 of them along streets, increasing the city's street-tree inventory by about one-fourth. A number of suburban communities are also going green, with simultaneous efforts to save trees and reduce costs. 

Portland has set a goal to increase its tree cover from 26 percent to 33 percent, propelled by a study it published last year (often cited by other jurisdictions) describing enormous public and environmental benefits from trees.

Among other things, the Rose City's street and park trees remove nearly 2 million pounds of pollutants and nearly 53 million pounds of carbon each year, according to the study, saving more than $3 million in services. Citywide, they also catch 1.3 billion gallons of storm water, according to the study, saving nearly $36 million on processing.

Elevations

City of Portland

Portland Airport (northeast - Columbia River): 20
Portland Waterfront (Willamette River): 30
Portland (City Hall): 70
Council Crest (southwest): 1,074
Mount Scott (southeast): 1,050
Sunset Highway (Sylvan): 750
Terwilliger (OHSU entrance): 315
Hollywood neighborhood: 200

Suburban Communities

Beaverton: 189
Damascus: 530
Estacada: 1,419
Gresham: 330
Hillsboro: 140
Lake Oswego (Mountain Park): 970
Lake Oswego (State Street): 100
Tigard: 66
Tigard (Bull Mountain): 711
Vancouver, Washington (Mill Plain Boulevard): 300
Vancouver, Washington (shipyards): 30

Distances

• 173 miles south of Seattle

• 639 miles north of San Francisco

• 250 miles from the California border via I-5

• 45 minutes from Mt. Hood

• 45 minutes from the wine country of the Willamette Valley

• 50 minutes from the spectacular Columbia Gorge

• About 90 minutes from the picturesque Oregon Coast