Johnson Creek (Willamette River)

Johnson Creek (Willamette River)

Geobox | River
name = Johnson Creek
category = Creek


image_size = 300
image_caption = Johnson Creek near Regner Road in Gresham
etymology = William Johnson, early settler
country = United States
country_

state = Oregon
district_type = County
district = Clackamas and Multnomah
source = Cascade Range foothills
source_location = near Cottrell
source_region = Clackamas County
source_state = Oregon
source_elevation_imperial = 745
source_elevation_note = [cite web | work = Geographic Names Information System (GNIS)| publisher = United States Geological Survey (USGS) | date = November 28, 1980 | url = http://geonames.usgs.gov/pls/gnispublic/f?p=gnispq:3:::NO::P3_FID:1122479 | title = Johnson Creek | accessdaymonth = May 1, | accessyear = 2008 Elevation derived from Google Earth search using GNIS source coordinates.]
source_length_imperial =
source_lat_d = 45
source_lat_m = 26
source_lat_s = 51
source_lat_NS = N
source_long_d = 122
source_long_m = 17
source_long_s = 18
source_long_EW = W
source_coordinates_note =
mouth_name = Willamette River
mouth_location = Milwaukie
mouth_district =
mouth_region = Multnomah County
mouth_state = Oregon
mouth_country =
mouth_note =
mouth_lat_d = 45
mouth_lat_m = 26
mouth_lat_s = 39
mouth_lat_NS = N
mouth_long_d = 122
mouth_long_m = 38
mouth_long_s = 36
mouth_long_EW = W
mouth_coordinates_note = cite web | work = Geographic Names Information System | publisher = United States Geological Survey | date = November 28, 1980 | url = http://geonames.usgs.gov/pls/gnispublic/f?p=gnispq:3:::NO::P3_FID:1122479 | title = Johnson Creek | accessdaymonth = March 13, | accessyear = 2008]
mouth_elevation_imperial = 26
mouth_elevation_note =
length_imperial = 25
length_round = 0
length_note =
watershed_imperial = 54
watershed_round = 0
watershed_note = cite web | title = Johnson Creek Watershed: A Decade of Change | publisher = Johnson Creek Watershed Council |year = 2006 | url = http://www.jcwc.org/pdf/JCWC_AnnualReport2006.pdf | format = pdf | accessdaymonth = March 13, | accessyear = 2008]
discharge_location = Milwaukie, convert|0.7|mi|km|1 from mouth
discharge_round = 2
discharge_imperial = 78
discharge_note = Note: Average discharge rate was calculated by adding average annual discharge rates for the 17 calendar years 1990–2006 and dividing by 17. cite web| title=USGS Surface-Water Annual Statistics for Oregon: USGS 14211550 Johnson Creek at Milwaukie | publisher = United States Geological Survey |year = 2008 | url = http://waterdata.usgs.gov/or/nwis/dv?cb_00060=on&format=gif_stats&begin_date=1989-04-22&end_date=2008-03-13&site_no=14211550&referred_module=sw| accessdaymonth = March 15, | accessyear = 2008 ]
discharge_max_imperial = 2170
discharge_min_imperial = 10
discharge1_location = Gresham
discharge1_imperial = 27
discharge1_note = Note: Average discharge rate was calculated by adding average annual discharge rates for the 7 calendar years 1999–2005 and dividing by 7. cite web| title=USGS Surface-Water Annual Statistics for the Nation: USGS 14211400 Johnson Creek at Regner Road at Gresham, Oregon | publisher = United States Geological Survey |year = 2008 | url = http://waterdata.usgs.gov/or/nwis/dv?cb_00060=on&format=gif_stats&begin_date=1989-04-22&end_date=2008-03-13&site_no=14211550&referred_module=sw| accessdaymonth = March 15, | accessyear = 2008 ]



map_size = 300
map_caption = Johnson Creek watershed
map1 = Oregon Locator Map.png map1_size = 300
map1_caption = Location of the mouth of Johnson Creek in Oregon
map1_locator = Oregon
commons =

Johnson Creek is a 25-mile (40 km) tributary of the Willamette River in the Portland metropolitan area of the U.S. state of Oregon. Part of the drainage basin of the Columbia River, its watershed consists of convert|54|sqmi|km2 of mostly urban land occupied by about 175,000 people as of 2006.cite web| title = Johnson Creek Watershed: A Decade of Change | publisher = Johnson Creek Watershed Council |year = 2006 | url = http://www.jcwc.org/pdf/JCWC_AnnualReport2006.pdf| format = pdf | accessdaymonth = March 13, | accessyear = 2008] Passing through the cities of Gresham, Portland, and Milwaukie, the creek flows generally west from the foothills of the Cascade Range through sediments deposited by glacial floods on a substrate of basalt. Though polluted, it is free-flowing along its main stem and provides habitat for salmon and other migrating fish.

Prior to European settlement, the watershed was heavily forested and was used by Native Americans of the Chinook band for fishing and hunting. In the 19th century, white settlers cleared much of the land for farming, and the stream is named for one of these newcomers, William Johnson, who in 1846 built a water-powered sawmill along the creek. By the early 20th century, a rail line parallel to the stream encouraged further residential and commercial development. As urban density increased in the floodplain, seasonal floods grew more damaging. In the 1930s the Works Progress Administration of the federal government lined the lower convert|15|mi|km of Johnson Creek with rock to control the floods. [cite web | title = About the Watershed | publisher = Portland Bureau of Environmental Services
year = 2008 | url = http://www.portlandonline.com/bes/index.cfm?c=33211 | accessdaymonth = April 7, | accessyear = 2008
] Despite this, the creek flooded 37 times between 1941 and 2006.cite web | title = USGS 14211500 Johnson Creek at Sycamore, OR | work = Surface Water for Oregon: Peak Streamflow | publisher = U.S. Geological Survey | year = 2008 | url = http://nwis.waterdata.usgs.gov/or/nwis/peak/?site_no=14211500&agency_cd=USGS | accessdaymonth = April 8, |accessyear = 2008 ] Since the 1990s, regional planners have tried to reduce flooding by controlling stormwater runoff, creating stream meanders, reducing erosion, replacing impervious surfaces, and protecting riparian buffers.

The Johnson Creek watershed includes the subwatersheds of Badger Creek, Sunshine Creek, Kelley Creek, Mitchell Creek, Veterans Creek, Crystal Springs Creek, and smaller streams. Parks along the creek and its tributaries include natural areas, a wildlife refuge, a rhododendron garden, a botanical garden, and a convert|21|mi|km|adj=on bicycle and pedestrian rail trail that follows the creek for much of its length.

Course

eight times.

For much of its course, the creek flows at almost right angles to the numbered avenues of southeast Portland and its eastern suburbs. The biggest numbers are near the headwaters, and the smallest numbers are near the mouth. The creek begins in uplands in Clackamas County east of Southeast 362nd Avenue and flows swiftly to the west for about convert|5|mi|km, crisscrossing the border between Clackamas County and Multnomah County 5 times in this upstream stretch, and passing under U.S. Route 26, the Mount Hood Highway, in Multnomah County at about convert|20|mi|km from the mouth. Shortly thereafter, it receives Badger Creek and Sunshine Creek from the left and the North Fork of Johnson Creek from the right.cite map |publisher = DeLorme Mapping |title = Oregon Atlas & Gazetteer |edition = 1991
section = 60–61
] cite web |publisher = Oregon Trout and University of Oregon |title = Johnson Creek Watershed Base Map |url = http://www.healthywatersinstitute.org/pdf/johnsonCreekMap.pdf | edition= 2006 | accessdaymonth = March 25, | accessyear = 2008]

Turning sharply, Johnson Creek flows swiftly northwest for about convert|3|mi|km, entering Gresham and shortly thereafter passing the United States Geological Survey (USGS) gauge at Regner Road, convert|16.2|mi|km from the mouth. Soon the creek enters Main City Park in Gresham, where it again turns sharply and flows slightly south of west. Here the slope flattens, and the stream runs more slowly for the next third of its course. Slightly west of Main City Park, it passes the Gresham Pioneer Cemetery. [cite web | title = Gresham Pioneer Cemetery | publisher = Metro | year=2008 | url = http://www.metro-region.org/index.cfm/go/by.web/id=12688 | accessdaymonth = March 31, | accessyear = 2008 ] Just beyond the cemetery, it receives Butler Creek on the left, enters Portland at about convert|13|mi|km from the mouth, and receives Kelley Creek on the left shortly thereafter. Mitchell Creek, a major tributary of Kelley Creek, enters Kelley Creek about convert|0.5|mi|km|1 south of Johnson Creek. Shortly thereafter, Johnson Creek passes the USGS gauge station at Sycamore, convert|10.2|mi|km from the mouth.

Meandering slowly through the Lents neighborhood of Portland, Johnson Creek receives Veterans Creek, which enters on the left from its headwaters in Happy Valley in Clackamas County. Johnson Creek passes under Interstate 205, and shortly thereafter begins to flow more swiftly again at Southeast 82nd Avenue, about convert|8|mi|km from the mouth. It then makes its sixth and seventh county-border crossings, dipping briefly into Clackamas County and back north into Multnomah County, and then runs near the border between Portland and Milwaukie along Johnson Creek Boulevard for about convert|2|mi|km. After passing under Oregon Route 99E (Southeast McLoughlin Boulevard) in Portland's Sellwood neighborhood, the creek turns sharply south about convert|1.5|mi|km from the mouth.

At Southeast 21st Avenue, it receives Crystal Springs Creek, which enters on the right. This tributary, about convert|2|mi|km long, begins on the Reed College campus, flows under the Blue Bridge in Reed Canyon, through the Crystal Springs Rhododendron Garden, and generally south to Johnson Creek. From its confluence with Crystal Springs Creek, Johnson Creek flows south about convert|1|mi|km|1, crossing the county border for the eighth and final time. After re-entering Clackamas County, it passes the USGS gauge station at Milwaukie, convert|0.7|mi|km from the mouth. Shortly thereafter, Johnson Creek empties into the Willamette River convert|18.5|mi|km| above its confluence with the Columbia River, which in turn flows about another convert|100|mi|km to the Pacific Ocean at Astoria.cite map |publisher = G.M. Johnson and Associates |title = City Street
url = |edition = 2007
]

Watershed

Geology and topography

The floodplain of Johnson Creek is a remnant of large glacial floods known as the Missoula Floods that deposited thick sediments between 13,000 and 15,000 years ago in the Columbia River Basin, including much of the Willamette Valley. Underlying the sediments are substantial thicknesses of basalt lavas from the Columbia River Basalt Group. The lava, exposed mainly in the uplands, has been folded and faulted to form a series of sub-basins, including the Johnson Creek watershed.

The watershed is a roughly rectangular area of about convert|54|sqmi|km2. The topography of the watershed varies greatly from the high point of about convert|1100|ft|m|0 above sea level in the Boring Hills near the creek's source to the low point of convert|26|ft|m|0 where the creek meets the Willamette River.

Slopes in the watershed range generally between 1 and 25 percent. Mount Scott and Powell Butte rise to about convert|1000|ft|m|0 and have slopes ranging from 10 to 30 percent. Gresham Butte and Hogan Butte, in Gresham, have the steepest slopes, including a few around 50 percent. The Boring Hills, of volcanic origin, rise more than convert|800|ft|m|0 higher than the terraces to the north and west. The Kelso Slope, a northwest-sloping dissected surface west of the canyon of the Sandy River, tilts down from about convert|1000|ft|m|0 above sea level near Sandy to about convert|400|ft|m|0 above sea level east of Gresham.

Formed by the ancestral Columbia and Willamette Rivers, the terraces north of Johnson Creek are generally underlain by permeable sand and gravel. Three isolated hills—Rocky Butte, Mount Tabor, and Kelly Butte—rise about convert|200|ft|m|0 to convert|400|ft|m|0 above the surrounding terraces. With the exception of Powell Butte, the terrain on the north side of Johnson Creek is less steep than on the south side of the creek, which includes Mount Scott and the Boring Lava Domes.cite web | last = Johnson Creek Watershed Council | title = Action Plan: Chapter 2.0, Watershed Assessment | publisher = Johnson Creek Watershed Council |year=2003 | url = http://www.jcwc.org/actionPlan/ch2a.htm#2.2.0.0| | accessdaymonth = March 17, | accessyear = 2008]

The eastern half of the watershed is more open and rural than the urban western half, which consists largely of residential areas with pockets of commerce and industry. An estimated 175,000 people lived in the watershed as of 2006.

oils

The potential for soil erosion varies throughout the watershed. Erosion is not a big threat in the northwestern part of the watershed, where the land is flat and developed, or in the northeast, dominated by low-erosion soils. In the southeast, soils have a medium risk of erosion, and soils around Powell Butte and the Boring Lava Domes have "an extremely high erodibility factor and are sensitive to ground disturbance".

The watershed's soils vary in their permeability and water-retaining capacity. South of the creek and at the eastern end of the watershed they consist mostly of clays with high runoff potential. Northern areas of the watershed are generally porous, with moderate to high permeability.

Hydrology

The watershed can be divided into two hydrologic areas with different infiltration rates. The northern area, comprising about 40 percent of the watershed, consists of the Portland Terraces, and the southern consists of the Boring Hills and the Kelso Slope. Most of the rain that falls on the northern area percolates into the ground, and most of the rain that falls on the southern area runs quickly into the creek or its tributaries. Rain that falls on the north generally has a more gradual, longer-lasting effect, sustaining the base flow of the creek during dry periods.

Of the estimated 30 creek systems that existed in the watershed before 19th-century settlement, fewer than a dozen remain above-ground or free-flowing. Generally, the tributaries begin south of the main stem and flow north; the major exception is Crystal Springs Creek, which begins as a groundwater discharge and flows south over relatively impermeable alluvial deposits to Johnson Creek at Johnson Creek Park. The other major tributaries are Veterans Creek, Kelley Creek, Butler Creek, Sunshine Creek, and Badger Creek. Crystal Springs Creek and Kelley Creek are the largest tributaries in terms of flow contribution.

Fill at Foster Road and Southeast 111th Avenue usually prevents stormwater runoff from a convert|9|sqmi|km2|adj=on area of the watershed in the Lents and Powellhurst-Gilbert neighborhoods from flowing directly into the creek. Instead, runoff is routed to sumps, where it percolates into the ground. Normal drainage patterns have also been altered further downstream in the Sellwood, Eastmoreland, Westmoreland, and Woodstock neighborhoods, where runoff flows into the Portland sewer system instead of into the creek.

Jurisdiction

Six local political jurisdictions overlap with the Johnson Creek watershed. In 2000, 38 percent of the watershed was in Portland's city limits, 24 percent in unincorporated Clackamas County, 23 percent in Gresham, 11 percent in unincorporated Multnomah County, 4 percent in Milwaukie, and 0.1 percent in Happy Valley. None of the cities lies entirely within the watershed. In 2000, Johnson Creek and its tributaries drained 53 percent of Gresham, 42 percent of Milwaukie, 19 percent of Happy Valley, and 14 percent of Portland. The watershed covered only 1.2 percent of unincorporated Multnomah County and less than 1 percent of unincorporated Clackamas County.

Neighboring watersheds on the east side of the Willamette River include Mount Scott Creek and Kellogg Creek, which flow through Milwaukie and drain directly into the Willamette; the Clackamas River, which drains the southeast suburbs and empties into the Willamette near Oregon City; the Sandy River, which drains the eastern suburbs and empties into the Columbia; and Fairview Creek and the Columbia Slough, which drain north Portland and Gresham, emptying into the Columbia.

Nineteenth-century maps also show numerous springs and small streams flowing into a wetland that covered an area of today's southeast Portland between Powell Boulevard (U.S. Route 26) and Johnson Creek, a distance of convert|2.25|mi|km|. Though most of the wetland complex has been filled in and built upon, remnants exist at the Crystal Springs Rhododendron Garden on Crystal Springs Creek. Old maps also show two streams flowing into a slough that drained part of the wetland. One flowed through the Clinton Street neighborhood, about six city blocks north of Powell Boulevard, and the other drained the Colonial Heights neighborhood, slightly further north near Ladd's Addition. These streams and most others in this area were diverted into the city sewer system and no longer appear on the surface. [cite web | last = Portland Bureau of Environmental Services | title = Taggart Aquatic Habitat | publisher = City of Portland | year = 2008 | url = http://www.portlandonline.com/bes/watershedapp/index.cfm?action=DisplayContent&SubWaterShedID=26&SubjectID=3&TopicID=26&SectionID=1
accessdaymonth = April 22, | accessyear = 2008
] A Johnson Creek diverted partly underground on the west side of the Willamette River in Portland has no relationship to the Johnson Creek on the east side. [cite web
title = West Side Historical Data: Buried Stream Channels and Lakes | publisher = City of Portland | year = 2008 | url = http://www.portlandonline.com/cso/index.cfm?a=dfcde&c=defbb | accessdaymonth = April 22, | accessyear = 2008
]

History

reduced this population to 88 by 1851, and in 1855 the tribe signed a treaty surrendering its lands, including Johnson Creek.cite web |first=Barbara |last=Taylor |title=Indian Use |year= 1999 |work=Salmon and Steelhead Runs and Related Events of the Clackamas River Basin: A Historical Perspective |publisher= U.S. Fish and Wildlife Service
url= http://www.portlandgeneral.com/community_and_env/hydropower_and_fish/clackamas/history/clackamas_river_history_full.pdf |format=pdf |accessdaymonth = September 29, | accessyear = 2008
]

By the middle of the 19th century, the European American newcomers had begun to remove vegetation, build sawmills, fell trees, fill wetlands, and farm in the fertile soil along Johnson Creek. The creek is named for one of these newcomers, William Johnson, who in 1846 settled in what later became the Lents neighborhood of Portland and operated a water-powered sawmill.cite web | title = Johnson Creek Park | publisher = Portland Parks and Recreation |year = 2008 | url = http://www.portlandonline.com/parks/finder/index.cfm?PropertyID=205&action=ViewPark | accessdaymonth = March 14, | accessyear = 2008] In early 1848 Lot Whitcomb, who would later found Milwaukie, filed a donation land claim and built a sawmill near the confluence of Johnson Creek and the Willamette River. [cite web |first=Harvey |last=Starkweather |title=Early Days and Ways in and around Milwaukie |date=January 12, 1939 |work=Federal Writers' Project/Works Progress Administration |url=http://www.rootsweb.ancestry.com/~ormultno/Stories/wpa/starkweather.htm |accessdaymonth = March 30, | accessyear = 2008] In 1886, plans were made for train tracks along the creek. In 1903, the Springwater Division Line, also known as the Portland Traction Company Line, the Cazadero Line, and the Bellrose Line, was built along Johnson Creek to provide rail transport for passengers and freight.cite web | title = Springwater Corridor | publisher = City of Portland, Parks and Recreation Department |year = 2008 | url = http://www.portlandonline.com/parks/finder/index.cfm?&action=ViewPark&propertyid=679 | accessdaymonth = March 31, | accessyear = 2008] Sellwood, Eastmoreland, Lents, and Pleasant Valley were among the new communities that grew up along the line. By the 1920s, housing began to replace creekside farms, a trend that has continued.cite web | title = History: Johnson Creek Watershed | publisher = City of Portland, Bureau of Environmental Services |year = 2008 | url = http://www.portlandonline.com/bes/index.cfm?c=33219 | accessdaymonth = March 12, | accessyear = 2008]

Floods

[
bioswale along Johnson Creek near Southeast 164th Avenue restores flood-control functions to former cow pasture. The red tubes protect new seedlings.]

By removing the original vegetation, rural and urban development of the Johnson Creek watershed induced more rapid storm runoff and expensive floods. As a flood-control measure in the 1930s, the Works Progress Administration of the federal government cleared and lined with rock about 90 percent of the creek between its mouth and Southeast 158th Avenue, about convert|15|mi|km from the mouth, creating an artificial channel convert|6|ft|m|0 to convert|10|ft|m|0 deep and convert|25|ft|m|0 to convert|50|ft|m|0 wide. Although substantially altering the stream and its aquatic life, this channel failed to prevent overflows, the largest of which damaged 1,200 structures in 1964.

Precipitation patterns in the Johnson Creek watershed have contributed to frequent high flows and floods along the creek, typically between November and February.cite web | last = Johnson Creek Watershed Council | title = Action Plan: Chapter 2.7, Flow and Hydrology | publisher = Johnson Creek Watershed Council |year=2003 | url = http://www.jcwc.org/actionPlan/ch2c.htm#2.7.0.0 | accessdaymonth = March 18, | accessyear = 2008 ] Based on records from 1961 to 1990, Portland's average annual precipitation, as measured at Portland International Airport along the Columbia River, is about convert|36|in|mm.cite web | last = National Weather Service, Portland, Oregon | title = Portland's Monthly and Annual Precipitation Totals | publisher = National Oceanic and Atmospheric Administration |year=2007 | url = http://www.wrh.noaa.gov/pqr/pdxclimate/PG65.html | accessdaymonth = March 18, | accessyear = 2008] About convert|21|in|mm| falls from November through February and only about convert|4|in|mm| from June through September. The airport, at about convert|30|ft|m|0 above sea level, is at essentially the same elevation as the mouth of Johnson Creek. Annual precipitation at higher elevations in the creek's upper watershed is much higher, more than convert|70|in|mm.

The floods primarily affect four areas in Portland: Tideman-Johnson Park at Southeast 45th Avenue, the area west of Southeast 82nd Avenue; Lents, and lower Powell Butte. The U.S. National Weather Service defines Johnson Creek's "flood stage", measured at USGS station 14211500 at Sycamore in Portland, as convert|11|ft|m, equivalent to a flow rate (discharge rate) of about convert|1200|cuft|m3 per second. [cite web | title = Johnson Creek at Sycamore | publisher = National Weather Service, Portland Weather Forecast Office | year = 2007 | url = http://ahps2.wrh.noaa.gov/ahps2/hydrograph.php?wfo=pqr&gage=syco3&view=1,1,1,1,1,1,1,1&toggles=10,7,8,2,9,15,6&type=2
accessdaymonth = April 8, | accessyear = 2008
] The USGS peak streamflow data collected by the stream gauge at that station show that the creek reached or exceeded convert|1200|cuft|m3 per second 37 times between 1941 and 2006; that is 37 floods in 65 years. Twenty of those floods exceeded convert|1500|cuft|m3 per second. At least seven of the floods caused major property damage. A more recent overflow occurred in December 2007, when the creek crested at convert|1.5|ft|m| above flood stage. [cite web | title = Update: Johnson Creek floods, closing nearby roads | work = The Oregonian | publisher = Oregon Live, L.L.C. | date = December 3, 2007 | url = http://blog.oregonlive.com/breakingnews/2007/12/johnson_creek_reaches_flood_st.html | accessdaymonth = April 7, | accessyear = 2008] [cite web | last = Ashton | first = David F. | title = Decade's second "10-year flood" inundates East Lents at Johnson Creek | work = East PDX News | publisher = East Portland News Service | date = December 12, 2007 | url = http://www.eastpdxnews.com/index.php?mod=article_detail&id_art=701 | accessdaymonth = April 13, | accessyear = 2008] Between 1978 and 1997, flood insurance claims totaling an estimated $2 million were paid for damage along the creek.

The biggest flood measured at Sycamore, convert|10.2|mi|km from the mouth of the creek, occurred in 1996. Exceeding the official flood stage of convert|11|ft|m| by more than convert|4|ft|m|, the creek reached convert|15.30|ft|m| on November 19 of that year. The second biggest flood occurred on December 22, 1964, when the creek reached convert|14.68|ft|m at Sycamore. [cite web | title = Johnson Creek at Sycamore | publisher = National Weather Service, Advanced Hydrological Prediction Service | year = 2007 | url = http://ahps2.wrh.noaa.gov/ahps2/hydrograph.php?wfo=pqr&gage=syco3 | accessdaymonth = March 23, | accessyear = 2008 ]

As of 2008, the USGS was monitoring Johnson Creek at Regner Road in Gresham, convert|16.3|mi|km from the mouth, and at Milwaukie, convert|0.7|mi|km| from the mouth, as well as at Sycamore. It also had stream-monitor stations on Kelley Creek and Crystal Springs Creek.cite web | title = Johnson Creek Basin Hydrologic Monitoring | publisher = United States Geologic Service | year = 2002 | url = http://or.water.usgs.gov/johnsoncreek/ | accessdaymonth = March 23, | accessyear = 2008] The Sycamore station was the oldest, having begun operation in 1941.

Proposals by agencies such as Metro, the regional government of the Portland metropolitan area, and the U.S. Army Corps of Engineers in the 1970s and 1980s to control Johnson Creek flooding were abandoned after groups of residents objected to every proposal.cite web | last = Johnson | first = Steven | title = Civic Innovation: Johnson Creek Watershed | work = Civic Life Portland, Oregon | publisher = Steven Johnson | date = | url = http://homepage.mac.com/stevenreedjohnson/johnsoncreek.html | accessdaymonth = March 14, | accessyear = 2008] In 1990, the City of Portland formed the Johnson Creek Corridor Committee from multiple agencies and citizen groups with varied interests related to the watershed. Led by the city's Bureau of Environmental Services, the combined groups in 2001 produced the Johnson Creek Restoration Plan, dividing the creek into 58 sections or reaches and listing their opportunities for restoration. Goals varied from section to section and included controlling storm water runoff, reducing erosion, replacing or mitigating impervious surfaces, protecting riparian buffers, and assisting salmon recovery.cite web | title = The Restoration Plan | publisher = City of Portland, Bureau of Environmental Sciences |year = 2001 | url = http://www.portlandonline.com/shared/cfm/image.cfm?id=67199|PDF | accessdaymonth = march 12, | accessyear = 2008] Through 2007, at least 75 site-specific restoration projects had been carried out in the Johnson Creek Watershed, ranging from the $1.2-million Brookside Project, a constructed wetland, to small riparian repair projects. Most involved voluntary citizen participation in all phases, including the long-term management and care of the sites.

Pollution

The Oregon Department of Environmental Quality (DEQ) rated Johnson Creek's water quality between 1986 and 1995 as "very poor". Monitoring the creek convert|0.2|mi|km|1 from the mouth, it recorded very high concentrations of nitrates and high concentrations of phosphates. Fecal coliform bacteria, total solids, and biochemical oxygen demand also impaired water quality. These conditions occurred throughout the year, and results for each parameter fell into the "very poor" category.cite web | last = Cude | first = Curtis | title = Laboratory and Environmental Assessment, Lower Willamette Basin | work = | publisher = Oregon Department of Environmental Quality | year = 1995 | url = http://www.deq.state.or.us/lab/wqm/wqindex/lowillsandy.htm | accessdaymonth = March 28, | accessyear = 2008 ] On the Oregon Water Quality Index (OWQI) used by DEQ, water quality scores can vary from 10 (worst) to 100 (ideal). The minimal seasonal average for Johnson Creek on this scale was 26, the second worst in the lower Willamette basin. By comparison, the minimal seasonal average in the nearby Willamette River at the Hawthorne Bridge in downtown Portland was 74 during the same years. Studies suggest that most pollutants of Johnson Creek do not come from point sources but are washed off urban and rural land surfaces during storms.cite web | last = Johnson Creek Watershed Council | title = Action Plan: Chapter 2.9, Water Quality | publisher = Johnson Creek Watershed Council |year=2003 | url = http://www.jcwc.org/actionPlan/ch2e.htm#2.9.0.0| accessdaymonth = March 28, | accessyear = 2008]

Elevated temperatures cause problems for aquatic life over the whole length of Johnson Creek. The Oregon standard for maximum temperatures conducive to salmonid rearing in the Willamette Basin is convert|17.8|°C|°F, and data show that the mean maximum summertime temperatures in Johnson Creek exceed this standard. The maximum temperature that Coho salmon can survive for short periods is convert|24|°C|°F.cite web | last = Davis | first = John A., P.E. | coauthors = Woodward-Clyde Consultants and Johnson Creek Watershed Council | title = Technical Memorandum No. 1: Johnson Creek and its Watershed — A Profile | publisher = City of Portland, Bureau of Environmental Services | year = 1994 | url = http://www.upa.pdx.edu/CWSP/WATSHED/jc/jc.htm | accessdaymonth = March 28 | accessyear = 2008] Thermographs at several locations on Johnson Creek in 1992 recorded maximum average weekly water temperatures higher than convert|18|°C|°F in June, July, and August, and an absolute maximum temperature of convert|24|°C|°F.

Studies conducted by DEQ, USGS, the City of Gresham, and other public agencies have identified DDT (dichloro-diphenyl-trichloroethane), dieldrin, polychlorinated biphenyls (PCB), chlordane, and polycyclic aromatic hydrocarbons (PAH) as carcinogenic pollutants of Johnson Creek. The creek has been classified as a “waterbody of concern” by the DEQ because of elevated levels of copper, chromium, and nickel in water and sediments. Generally, metal concentrations increase downstream.

Biology

Macroinvertebrates and fish

communities in the urban streams were degraded compared to the regional reference creeks.

Most fish species in Johnson Creek tolerate warm water and disturbed conditions. These include red-sided shiners, sculpin, suckers, and speckled dace.cite web | last = Portland Bureau of Environmental Services | title = Biological Communities in the Johnson Creek Watershed | publisher = City of Portland | year = 2008 | url = http://www.portlandonline.com/bes/index.cfm?c=33216 | accessdaymonth = March 25, | accessyear = 2008] Large populations of salmon inhabited the creek before urban construction altered the watershed and the stream channel, and in the 21st century, the creek and its tributaries still provide habitat for smaller numbers of Chinook salmon, Coho salmon, steelhead, and cutthroat trout.cite web | title = Johnson Creek Watershed | publisher = City of Portland, Bureau of Environmental Services |year = 2008 | url = http://www.portlandonline.com/bes/index.cfm?&c=dccab | accessdaymonth = March 12, | accessyear = 2008] cite web| last = Portland Bureau of Environmental Services | title = Biological Communities in the Johnson Creek Watershed | publisher = City of Portland | year = 2008 | url = http://www.portlandonline.com/bes/index.cfm?c=33216 | accessdaymonth = March 25, | accessyear = 2008] Chinook and Coho salmon and steelhead are listed as threatened species in the Lower Columbia River watershed, of which Johnson Creek is part. [cite web | title = Endangered Species Act Status of West Coast Salmon & Steelhead | publisher = National Oceanic and Atmospheric Administration | year = 2008 | url = http://www.nwr.noaa.gov/ESA-Salmon-Listings/upload/snapshot0208.pdf | format = pdf | accessdaymonth = March 27, | accessyear = 2008 ] Under provisions of the federal Endangered Species Act, a species is "threatened" if it is likely to become endangered, and it is "endangered" if it is likely to become extinct through all or a significant part of its range. [cite web | title = Endangered Species Act | publisher = NOAA Office of Protected Resources | year = 2008 | url = http://www.nmfs.noaa.gov/pr/laws/esa/ | accessdaymonth = March 27, | accessyear = 2008 ]

Wildlife

Before the area became urban, large mammals including bobcats, black bears, foxes, cougars, wolves, and elk thrived in the area. Common species in the 21st century include Crow, Robin, Starling, Song Sparrow, Bewick's Wren, House Finch, Cedar Waxwing, Violet-green Swallow, Belted Kingfisher, Great Blue Heron, Mallard, Wood Duck, Bushtit, Black-capped Chickadee, raccoon, opossum, nutria, and moles. Less developed areas support black-tailed deer, coyotes, deer mice, voles, bats, Western Flycatchers, Black-headed Grosbeaks, Orange-crowned Warblers, Common Mergansers, and woodpeckers. Other wildlife in the watershed include beaver, river otter, hawks, owls, geese, and an occasional eagle.cite web | title = Meet the Creek | publisher = Johnson Creek Watershed Council |year = 2003 | url = http://www.jcwc.org/johnsonCreek/creek.htm |accessdaymonth = March 12, | accessyear = 2008]

Johnson Creek and its watershed are home to life forms that, under Oregon law, have been listed as "sensitive" species. These are naturally reproducing native animals that may become threatened or endangered throughout all or any significant part of their range in Oregon. [cite web | title = Wildlife Diversity (Nongame) Program | publisher = Oregon Department of Fish and Wildlife | year = 2008 | url = http://www.dfw.state.or.us/wildlife/diversity/species/sensitive_species.asp | accessdaymonth = March 25, | accessyear = 2008 ] Such animals known to live in the Johnson Creek watershed include long-toed, northwestern, and Columbia salamanders, red-legged frogs, painted turtles, great horned owls, toads, hawks, and coyotes. A plant found on Powell Butte, tall bugbane ("Actaea elata"), is also listed as a sensitive species.

Vegetation

The watershed lies in the Willamette Valley ecoregion designated by the U.S. Environmental Protection Agency (EPA). It was covered until the mid-19th century with Oregon ash, red alder, and western redcedar forests and scattered black cottonwood groves in riparian areas. Douglas-fir and Oregon white oak grew in the uplands.cite web | last = Thorson | first = T.D. | coauthors = Bryce, S.A.; Lammers, D.A., "et al." | title = Ecoregions of Oregon (front side of color poster with map, descriptive text, summary tables, and photographs) | publisher = United States Geological Survey | year = 2003 | url = ftp://ftp.epa.gov/wed/ecoregions/or/or_front.pdf | format = pdf | accessdaymonth = June 19, | accessyear = 2008 Reverse side [ftp://ftp.epa.gov/wed/ecoregions/or/or_back.pdf here] ] About 57 percent of the watershed is vegetated, including grass, trees, blackberries, and all other plant life. Seventy-two percent of the watershed lies within the urban growth boundary. Of the total land area, 57 percent is single-family residential, 12 percent multi-family, 10 percent commercial, 8 percent rural, and 13 percent parks and open space. Of the rural agricultural total, 50 percent consists of cultivated crops or pasture, 29 percent tree and ornamental nurseries, 2 percent cultivated cane crops, and 19 percent is unclassified.cite web | last = Healthy Waters Institute | title = Johnson Creek Regional Information | publisher = Oregon Trout | url = http://www.healthywatersinstitute.org/pdf/Johnson%20Creek%20Regional%20Information.pdf | format = pdf | accessdaymonth = March 16, | accessyear = 2008 ]

Creek restoration projects since the 1990s have reduced the amount of Himalayan blackberry, an invasive species that had come to dominate much of the landscape near the creek. New plantings include native shrubs and trees such as red-osier dogwood, elderberry, Indian plum, and willow. City parks adjacent to Johnson Creek have acreage devoted to marsh with shrubs, cattails, and smartweed, forested wetland, riparian woodland, open meadow, and orchard trees.

Parks

, a hiking and biking trail that circles the Portland metropolitan area and intersects with similar trails. [cite web | title = Springwater Corridor | publisher = Portland Parks and Recreation |year = 2008 | url = http://www.portlandonline.com/parks/finder/index.cfm?PropertyID=679&action=ViewPark |accessdaymonth = April 7, | accessyear = 2008]

Creekside parks include Johnson Creek Park, about convert|4.5|acre|ha|1 of natural areas and paths in Sellwood; the Crystal Springs Rhododendron Garden, along Crystal Springs Creek; Tideman Johnson Natural Area, about convert|7.2|acre|ha|1 of natural areas and paths;Tideman Johnson settled in the area in 1878 but bears no relation to the Johnson after whom the creek was named. Tideman's great-grandson, Steve Johnson, still lives along the creek and is an adjunct professor of urban studies and planning at Portland State University and a founder of a council that links interests along the stream. cite web | title= Up Johnson Creek |first=Spencer
last=Heinz |date=February 9, 2006 |publisher="The Oregonian" |url = http://0-infoweb.newsbank.com.catalog.multcolib.org/iw-search/we/InfoWeb?p_product=NewsBank&p_theme=aggregated5&p_action=doc&p_docid=10FB1CA7597BC5F0&p_docnum=1&p_queryname=1 | accessdaymonth = April 27, | accessyear = 2008
] [cite web | title = Tideman Johnson Natural Area | publisher = Portland Parks and Recreation |year = 2008 | url = http://www.portlandonline.com/parks/finder/index.cfm?PropertyID=815&action=ViewPark|accessdaymonth = March 14, | accessyear = 2008] Leach Botanical Garden, about convert|16|acre|ha|0, a public garden dedicated to the study of botany and horticulture with an emphasis on plants of the Pacific Northwest; [cite web | title = Leach Botanical Garden | publisher = Portland Parks and Recreation |year = 2008 | url = http://www.portlandonline.com/parks/finder/index.cfm?PropertyID=226&action=ViewPark|accessdaymonth = March 14, | accessyear = 2008] Beggars Tick Wildlife Refuge, a wetland of convert|20|acre|ha|0; [cite web | title = Beggars-tick Wildlife Refuge | publisher = Metro |year = 2008 | url = http://www.metro-region.org/index.cfm/go/by.web/id=154 | accessdaymonth = March 14, | accessyear = 2008] [Beggars Tick, Bidens frondosa, is an invasive weed.] Powell Butte Nature Park, about convert|608|acre|ha|0 on an extinct cinder cone volcano, including natural areas and hiking, biking, and equestrian trails; [cite web | title = Powell Butte Nature Park | publisher = Portland Parks and Recreation |year = 2008 | url = http://www.portlandonline.com/parks/finder/index.cfm?PropertyID=528&action=ViewPark|accessdaymonth = March 14, | accessyear = 2008] and the City of Gresham's Main City Park, about convert|18|acre|ha|0 including sports fields, picnic areas, and trails. [cite web | title = Main City Park | publisher = City of Gresham |year = 2005 | url = http://www.ci.gresham.or.us/departments/des/parksandrec/parkfinder2/maincitypark/|accessdaymonth = March 14, | accessyear = 2008]

In 2007 Metro purchased two parcels of land totaling convert|102|acre|m2 for preservation adjacent to Johnson Creek on Clatsop Butte, south of Foster Road near Powell Butte and Portland's Pleasant Valley neighborhood. The purchases cost $10.9 million, drawing on bonds approved by a 2006 ballot measure. They were praised by conservationists but questioned by others who thought Metro paid too much. [cite web |title=Good buys on green space? |first=Eric
last=Mortenson |work = The Oregonian | date = December 17, 2007
url = http://www.oregonlive.com/news/oregonian/index.ssf?/base/news/1197865514170840.xml&coll=7 |accessdaymonth = April 23, | accessyear = 2008
]

ee also

* List of rivers of Oregon
* Watersheds managed wholly or partly by the city of Portland:
**Columbia Slough
**Fanno Creek
**Balch Creek
**Tryon Creek
**Bull Run
**Willamette River

Notes

External links

* [http://www.healthywatersinstitute.org/pdf/johnsonCreekMap.pdf Johnson Creek watershed topographic map]
* [http://www.jcwc.org/ Johnson Creek Watershed Council]
* [http://www.oregon-plan.org/OPSW/stories/willamette.shtml Kelley Creek confluence restoration]


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