The Alameda Ridge is a large

gravel bar A bar in a river is an elevated region of sediment (such as sand or gravel) that has been deposited by the flow. Types of bars include mid-channel bars (also called braid bars and common in braided rivers), point bars (common in meandering ...

located in

Portland Portland most commonly refers to: * Portland, Oregon, the largest city in the state of Oregon, in the Pacific Northwest region of the United States * Portland, Maine, the largest city in the state of Maine, in the New England region of the northeas ...

Oregon Oregon () is a state in the Pacific Northwest region of the Western United States. The Columbia River delineates much of Oregon's northern boundary with Washington, while the Snake River delineates much of its eastern boundary with Idaho. T ...

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territori ...

. It forms a

ridgeline A ridge or a mountain ridge is a geographical feature consisting of a chain of mountains or hills that form a continuous elevated crest for an extended distance. The sides of the ridge slope away from the narrow top on either side. The line ...

above much of north and southeast Portland, with views of downtown and west side neighborhoods. Alameda Ridge runs through the Madison South,

Roseway ''Roseway'' is a wooden gaff-rigged schooner launched on 24 November 1925 in Essex, Massachusetts. She is currently operated by World Ocean School, a non-profit educational organization based in Boston, Massachusetts, and is normally operated ...

, Rose City Park, Beaumont-Wilshire,

Alameda An alameda is a Avenue (landscape), street or path lined with trees () and may refer to: Places Canada *Alameda, Saskatchewan, town in Saskatchewan **Grant Devine Dam, formerly ''Alameda Dam'', a dam and reservoir in southern Saskatchewan Chile ...

, and Sabin neighborhoods.

Geologic history

Alameda Ridge was formed between 15,000 and 13,000 years ago at the end of the last

ice age An ice age is a long period of reduction in the temperature of Earth's surface and atmosphere, resulting in the presence or expansion of continental and polar ice sheets and alpine glaciers. Earth's climate alternates between ice ages and gre ...

when the ice dam containing

Glacial Lake Missoula Lake Missoula was a prehistoric proglacial lake in western Montana that existed periodically at the end of the last ice age between 15,000 and 13,000 years ago. The lake measured about and contained about of water, half the volume of Lake Mic ...

collapsed some 40 times, causing the

Missoula Floods The Missoula floods (also known as the Spokane floods or the Bretz floods or Bretz's floods) were cataclysmic glacial lake outburst floods that swept periodically across eastern Washington and down the Columbia River Gorge at the end of the las ...

, some of the largest floods known on earth. The flood waters spilled across

Idaho Idaho ( ) is a state in the Pacific Northwest region of the Western United States. To the north, it shares a small portion of the Canada–United States border with the province of British Columbia. It borders the states of Montana and Wyomi ...

and eastern

Washington Washington commonly refers to: * Washington (state), United States * Washington, D.C., the capital of the United States ** A metonym for the federal government of the United States ** Washington metropolitan area, the metropolitan area centered o ...

, surged down the Columbia River and through the Gorge, flooding the

Willamette Valley The Willamette Valley ( ) is a long valley in Oregon, in the Pacific Northwest region of the United States. The Willamette River flows the entire length of the valley and is surrounded by mountains on three sides: the Cascade Range to the eas ...

as far south as Eugene, Oregon. These floods covered the city of

Portland, Oregon Portland (, ) is a port city in the Pacific Northwest and the list of cities in Oregon, largest city in the U.S. state of Oregon. Situated at the confluence of the Willamette River, Willamette and Columbia River, Columbia rivers, Portland is ...

in approximately of water, carving out Sullivan's Gulch, the large

ravine A ravine is a landform that is narrower than a canyon and is often the product of streambank erosion.Interstate 84, and depositing large volumes of unconsolidated silt, sand, gravel, and boulders.USGS Cascades Volcano Observatory
/ref> As the west-flowing waters rushed around

Rocky Butte Rocky Butte (previously known as Mowich Illahee and Wiberg Butte) is an extinct cinder cone butte in Portland, Oregon, United States. It is also part of the Boring Lava Field, a group of volcanic vents and lava flows throughout Oregon and Wash ...

, a volcanic cinder cone in the Boring Lava Field, sediments were deposited on the west side of the butte forming an approximately 100 to high bar that became Alameda Ridge. The ridge extends west roughly from Rocky Butte to approximately 15th Avenue and Skidmore Street.

Human history

Portland residents began building on Alameda Ridge around the turn of the 20th century, as electric streetcars allowed real estate development to grow away from the city core. The steep hillside on the south side of the ridge provides beautiful views of Northeast Portland and the downtown skyline. This allowed early developers to cater to wealthy individuals. Because the Ridge was developed before cars were the primary mode of transportation, many public stairways were built along the southern hillside to allow easier travel between neighborhoods. These stairways are still present today and are maintained by the City of Portland. Alameda Ridge runs through the Madison South,

, Rose City Park, Beaumont-Wilshire,

, and Sabin Neighborhoods, with some of the most expensive homes (some being worth more than one million dollars) located along the upper edge of the southern slope in the Rose City Park,

Beaumont Beaumont may refer to: Places Canada * Beaumont, Alberta * Beaumont, Quebec England * Beaumont, Cumbria * Beaumont, Essex ** Beaumont Cut, a canal closed in the 1930s * Beaumont Street, Oxford France (communes) * Beaumont, Ardèche * ...

Neighborhoods. A growing concern among locals is the present-day removal or renovation of long-existing structures due to the need to repair them as well as the pressure to conform to more modern styles of living.

Gallery

Image:Alameda Stairway.jpg, Stairway at 19th Ave. Image:Alameda Stairway 2.jpg, Stairway at 50th Ave. Image:Alameda Stairway 3.jpg, Stairway at 51st Ave. Image:Alameda Wistaria.jpg, Alameda Ridge to the west from NE Wistaria Dr.

References

External links

Portland Neighborhood MapNortheast Neighborhoods
- Portland Connected {{coord, 45, 32, 42, N, 122, 33, 58, W, display=title, type:landmark Geology of Oregon