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 meanderin ...
located in
Portland
Portland most commonly refers to:
*Portland, Oregon, the most populous city in the U.S. state of Oregon
*Portland, Maine, the most populous city in the U.S. state of Maine
*Isle of Portland, a tied island in the English Channel
Portland may also r ...
,
Oregon
Oregon ( , ) is a U.S. state, state in the Pacific Northwest region of the United States. It is a part of the Western U.S., with the Columbia River delineating much of Oregon's northern boundary with Washington (state), Washington, while t ...
,
United States
The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...
. It forms a
ridgeline
A ridge is a long, narrow, elevated geomorphologic landform, structural feature, or a combination of both separated from the surrounding terrain by steep sides. The sides of a ridge slope away from a narrow top, the crest or ridgecrest, wi ...
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, Essex, Massachusetts. She is currently operated by World Ocean School, a non-profit educational organization based in Boston, Massachusetts, Bos ...
,
Rose City Park,
Beaumont-Wilshire,
Alameda
An alameda is a 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
* Alameda (Santi ...
, 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 g ...
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 Mi ...
collapsed some 40 times, causing the
Missoula Floods, some of the largest floods known on earth. The flood waters spilled across
Idaho
Idaho ( ) is a landlocked U.S. state, state in the Pacific Northwest and Mountain states, Mountain West subregions of the Western United States. It borders Montana and Wyoming to the east, Nevada and Utah to the south, and Washington (state), ...
and eastern
Washington
Washington most commonly refers to:
* George Washington (1732–1799), the first president of the United States
* Washington (state), a state in the Pacific Northwest of the United States
* Washington, D.C., the capital of the United States
** A ...
, surged down the
Columbia River
The Columbia River (Upper Chinook language, Upper Chinook: ' or '; Sahaptin language, Sahaptin: ''Nch’i-Wàna'' or ''Nchi wana''; Sinixt dialect'' '') is the largest river in the Pacific Northwest region of North America. The river headwater ...
and through the
Gorge
A canyon (; archaic British English spelling: ''cañon''), gorge or chasm, is a deep cleft between escarpments or cliffs resulting from weathering and the erosion, erosive activity of a river over geologic time scales. Rivers have a natural tend ...
, flooding the
Willamette Valley
The Willamette Valley ( ) is a 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 east, the ...
as far south as
Eugene, Oregon
Eugene ( ) is a city in and the county seat of Lane County, Oregon, United States. It is located at the southern end of the Willamette Valley, near the confluence of the McKenzie River (Oregon), McKenzie and Willamette River, Willamette rivers, ...
. These floods covered the city of
Portland, Oregon
Portland ( ) is the List of cities in Oregon, most populous city in the U.S. state of Oregon, located in the Pacific Northwest region. Situated close to northwest Oregon at the confluence of the Willamette River, Willamette and Columbia River, ...
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. Ravines are typically classified as larger in scale than gullies, although smaller than valleys. Ravines may also be called a cleuch, dell, ...
that holds
Interstate 84, and depositing large volumes of unconsolidated silt, sand, gravel, and boulders.
[USGS Cascades Volcano Observatory](_blank)
/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 Was ...
, a volcanic cinder cone in the Boring Lava Field
The Boring Lava Field (also known as the Boring Volcanic Field) is a Plio-Pleistocene volcanic field of cinder cones, small shield volcanoes, and lava flows in the northern Willamette Valley of the U.S. state of Oregon and adjacent southwest ...
, 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, Roseway
''Roseway'' is a wooden gaff-rigged schooner launched on 24 November 1925 in Essex, Massachusetts, Essex, Massachusetts. She is currently operated by World Ocean School, a non-profit educational organization based in Boston, Massachusetts, Bos ...
, Rose City Park, Beaumont-Wilshire, Alameda
An alameda is a 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
* Alameda (Santi ...
, 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, Alameda
An alameda is a 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
* Alameda (Santi ...
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 Map
Northeast Neighborhoods
- Portland Connected
{{coord, 45, 32, 42, N, 122, 33, 58, W, display=title, type:landmark
Geology of Oregon