Balch Creek is a tributary of the Willamette River in the U.S. state of Oregon. Beginning at the crest of the Tualatin Mountains (West Hills), the creek flows generally east down a canyon along Northwest Cornell Road in unincorporated Multnomah County and through the Macleay Park section of Forest Park, a large municipal park in Portland. At the lower end of the park, the stream enters a pipe and remains underground until reaching the river. Danford Balch, from whom the creek takes its name, settled a land claim along the creek in the mid-19th century. After murdering his son-in-law, he became the first person legally hanged in Oregon.
Basalt, mostly covered by silt in the uplands and sediment in the lowlands, underlies the Balch Creek watershed. The upper part of the watershed includes private residential land, an Audubon Society nature sanctuary, and part of Forest Park. Mixed conifer forest of Coast Douglas-fir, western redcedar, and western hemlock with a well-developed understory of shrubs and flowering plants is the natural vegetation. Sixty-two species of mammals and more than 112 species of birds use Forest Park. A small population of cutthroat trout resides in the stream, which in 2005 was the only major water body in Portland that met state standards for bacteria, temperature, and dissolved oxygen.
Although nature reserves cover much of the upper and middle parts of the watershed, industrial sites dominate the lower part. Historic Guild's Lake occupied part of the lower watershed through the 19th century, and in 1905 city officials held the Lewis and Clark Centennial Exposition there on an artificial island. After the exposition, developers converted the lake and its surrounds to industrial use, and in 2001 the Portland City Council declared the site to be an "industrial sanctuary".
From its source, the creek runs east on private property near Forest Park, a large municipal park in Portland, before turning briefly south about from the mouth. Soon thereafter, the stream receives an unnamed tributary on the right and turns southeast on private property along Northwest Cornell Road. It enters the city and the Portland Audubon Sanctuary simultaneously about from the mouth, receives two more unnamed tributaries on the right, and flows northeast, entering the part of Forest Park known as Macleay Park.
For about the creek parallels Wildwood Trail, the main hiking trail in Forest Park, until reaching a former public restroom known as the Stone House. From here Balch Creek runs beside the Lower Macleay Trail, another hiking trail, for about . Near Northwest Thurman Street, roughly from the mouth, the creek flows through a trash-catching rack into an diameter storm sewer. The water empties into the Willamette River in the city's Northwest Industrial neighborhood at Outfall 17. About below this outfall, the Willamette enters the Columbia River.
The Bureau of Environmental Services (BES) of the city of Portland monitored the flow of Balch Creek from June 1996 through September 2002 at a site, Node ABB857, where the stream leaves the surface and enters a storm sewer in Macleay Park. BES reported an average summer flow of , a maximum of , and a minimum of 0. The average flow in winter was , with a maximum of and a minimum of 0.
Measurements taken during an individual spring, from mid-May to mid-July 2002, showed the flow starting at about and dwindling to 0 by early June. The flow through June depended partly on the weather; the highest flow, , occurred after a rain. Measurements taken during an individual autumn, late August to late December 2001, were close to zero until November. The largest flows during that season, , occurred after many days of rain.
About 15,000 years ago, cataclysmic ice age events known as the Missoula Floods or Bretz Floods originating in the Clark Fork region of northern Idaho inundated the Columbia River basin many times. These floods deposited huge amounts of debris and sediment and created new floodplains in the Willamette Valley. From then until the 19th century, the lower Balch Creek watershed consisted of swampy marshlands and shallow semi-permanent lakes such as historic Guild's Lake. The final or so of historic Balch Creek flowed across this floodplain.
The creek is named for Danford Balch, who settled a donation land claim upstream of the Guild property in 1850. After a man from a neighboring family eloped with a Balch daughter, Balch killed him with a shotgun. On October 17, 1859, at a public gallows he became the first person to be hanged by the State of Oregon.
Macleay Park takes its name from Donald Macleay, a Portland merchant and real-estate developer who acquired what had been the Balch property. In 1897, he donated the land for a park on condition that the city provide transport to the park for hospital patients and build paths wide enough for wheelchairs.
One of the first industries in the Guild's Lake area was a sawmill built in the 1880s. Although large parts of the land remained undeveloped until the early 20th century, lumber mills, grain storage structures, railroads, and docks appeared along the waterfront. The Guild's Lake Rail Yard, built by the Northern Pacific Railway in the 1880s, became an important switching yard for trains.
In 1905, the Lewis and Clark Centennial Exposition, held on an artificial island in Guild's Lake, helped spur growth in the area. After the exposition ended, developers filled the lake and its surrounds with soil sluiced from parts of the Balch Creek watershed in the West Hills above the floodplain or dredged from the Willamette River. Civic leaders promoted the Guild's Lake area as a good place for industry, and by the mid-1920s the lake was gone. The USGS places historic Guild's Lake at coordinates at an elevation of above sea level between what later became Northwest Saint Helens Road and Northwest Yeon Street, slightly west of Northwest 35th Avenue in Portland.
Between the 1890s and the 1930s, channel-deepening in the Willamette River improved the city's status as a deep-water seaport, as did completion in 1914 of a port terminal. Guild's Lake, close to highways as well as marine and rail terminals, became the most important industrial area in Portland. After World War II, chemical and petroleum processing and storage, metals manufacturing, and other large industries expanded in the area. In 2001, the Portland City Council adopted the Guild's Lake Industrial Sanctuary Plan aimed at protecting the area's "long-term economic viability as an industrial district."
The Balch Creek watershed consists of , equal to . About 27 percent is zoned for parks and other open space, and about 20 percent is zoned for heavy industry near the Willamette River. Multnomah County has jurisdiction over , about a quarter of the watershed. Lands zoned for residential farms and forests occupy about 13 percent of the total, mostly along the watershed's western edge. A mixture of residential, commercial, and other designations make up smaller segments. About 1,600 people lived in the Balch Creek watershed in 2000, and about 6,700 people worked there. Nearby watersheds include those of other small streams flowing directly into the Willamette along the east flank of the West Hills. The city refers to these as the Johnson-Nicolai subwatershed to the southeast, and the Kittredge and Salzman subwatersheds to the northwest. The Balch Creek watershed abuts the Tualatin River watershed at the crest of the West Hills.
Rainfall in the watershed from 1977 to 2002 averaged about per year. About of the total fell from November through April, and about fell from May through October. Minor flooding has occurred near the trash rack and caused occasional basement flooding along nearby streets.
Above the floodplain, much of the habitat in the watershed consists of mixed conifer forest. Trees and shrubs, including stands of red alder and cottonwood trees, cover about 88 percent of the middle reaches. Near the headwaters, the forests consist mainly of mixed conifers and hardwoods with a few older Douglas-firs. Common species include big leaf maple, willow, western hemlock, red alder, western red cedar, and Douglas-fir. Most of this forest is relatively young. In Forest Park, old growth forest, undisturbed for 250 years or more, exists mainly in isolated patches.
Forest Park and other areas of the watershed have an understory of well-developed shrubs including ferns, Oregon-grape, vine maple, salal, red huckleberry, Fendler's waterleaf, Indian plum, salmonberry, and stinging nettle. Among the prominent wildflowers are wild ginger, Hooker's fairy bells, vanilla leaf, evergreen violet, and trillium. Rare or uncommon species include old conifers, Western wahoo shrubs, and ornamental dawn redwoods. Invasive species are English ivy, European holly, clematis, morning glory, and Himalayan blackberry.
Nearby tracts of habitat strongly affect the wildlife in the Balch Creek watershed. This is especially true of Forest Park, which extends into other watersheds to the northwest. Birds and animals from these watersheds and from the Tualatin River valley, the Coast Range, the Willamette River, Sauvie Island, the Columbia River, and the Vancouver, Washington, lowlands, move in and out of the park with relative ease. Sixty-two mammal species, including the northern flying squirrel, black-tailed deer, creeping vole, bobcat, coyote, Mazama pocket gopher, little brown bat, Roosevelt elk, and Pacific jumping mouse use Forest Park. Blue Grouse, Great Horned Owl, Hairy Woodpecker, Bewick's Wren, Orange-crowned Warbler, Osprey, and Hermit Thrush are among the 112 species of birds that frequent the area. Amphibian species seen at the Audubon Society pond include rough-skinned newts, Pacific tree frogs, and salamanders.
Pressure from habitat loss, pollution, hunting, and urban development has reduced or eliminated the large predators such as wolves, bears, and wild cats and has led to increased numbers of small predators such as weasels and raccoons. Roads through the watershed severely hamper the movement of large animals. Invasive plant species such as English ivy have made the habitat simpler and less supportive of native insects and the salamanders and other amphibians that feed on them. Citizen groups such as the No Ivy League and Friends of Forest Park have engaged in projects to remove ivy, to plant native species, and to widen and protect riparian zones.