Extensive timber cutting in the Sandy River basin began in the mid-19th century in response to a demand for wood from the Portland metropolitan area.
Logging intensified in the lower basin through the 20th century as sawmills became established in Sandy, Boring, Brightwood and other settlements in the region, and railroad spurs extended into the forests.
In 1904, President Theodore Roosevelt signed into law the Bull Run Trespass Act to forbid activities such as camping and livestock grazing in the Bull Run Reserve.
Except for activity related to the waterworks, the protected area changed little until the 1950s, when the United States Forest Service began to advocate logging in the Reserve.
After the U.S. Congress passed the Multiple Use – Sustained Yield Act of 1960 stressing timber production in the national forests, the Forest Service in the 1960s and 1970s built about 170 miles (270 km) of forest roads in the watershed.
Before the road-building and heavy logging, "The watershed [had] remained almost inviolable for nearly 60 years, its runoff protected by a largely unbroken expanse of centuries-old trees," according to a member of the Bull Run Advisory Committee, a scientific panel commissioned by the City of Portland in 1977 to review issues related to Bull Run.

In 1973, Joseph Miller, Jr., a retired Portland physician, sued the Forest Service, claiming that its logging violated the Bull Run Trespass Act.
In 1976, U.S. District Judge James M. Burns agreed, and logging was halted.
Shortly thereafter, Congress rescinded the Bull Run Trespass Act and replaced it with the Bull Run Watershed Management Act of 1977, which created the Bull Run Watershed Management Unit (BRWMU) (replacing the Bull Run Reserve) and legalized further Bull Run logging unless it could be shown to reduce water quality.
Logging and the debate about logging continued.
In 1994 about 75 percent of the BRWMU was made into a reserve for protecting the northern spotted owl and other species dependent on old-growth forests.
In February 1996, runoff from unusually heavy rains in the watershed washed so much eroded soil into the Bull Run storage reservoirs that the City had to shut down the Bull Run supply and switch during the crisis to its emergency supply from a well field along the Columbia River.
Later in 1996, Congress passed the Oregon Resources Conservation Act, which prohibited logging on all Forest Service lands within the Bull Run water supply drainage and another 3,500 acres (14 km²) of land that drained to the lower Bull Run River.
In 2001, the Little Sandy Act extended the prohibitions to the entire BRWMU and public lands along the Little Sandy River.

Between 1958 and 1993, when the last timber-cutting took place in the BRWMU, about 14,500 acres (59 km²), roughly 22 percent of the water supply drainage, were logged.
Since then, to reduce erosion from the outmoded logging infrastructure, the Forest Service and the water bureau have been decommissioning parts of the Bull Run forest road network, which had grown to 346 miles (557 km).
By autumn 2008, they had closed 78 miles (126 km) of roads, were dismantling another 63 miles (101 km), and were removing 245 culverts.
Extensive timber cutting in the Sandy River basin began in the mid-19th century in response to a demand for wood from the Portland metropolitan area. Logging intensified in the lower basin through the 20th century as sawmills became established in Sandy, Boring, Brightwood and other settlements in the region, and railroad spurs extended into the forests. In 1904, President Theodore Roosevelt signed into law the Bull Run Trespass Act to forbid activities such as camping and livestock grazing in the Bull Run Reserve. Except for activity related to the waterworks, the protected area changed little until the 1950s, when the United States Forest Service began to advocate logging in the Reserve. After the U.S. Congress passed the Multiple Use – Sustained Yield Act of 1960 stressing timber production in the national forests, the Forest Service in the 1960s and 1970s built about 170 miles (270 km) of forest roads in the watershed. Before the road-building and heavy logging, "The watershed [had] remained almost inviolable for nearly 60 years, its runoff protected by a largely unbroken expanse of centuries-old trees," according to a member of the Bull Run Advisory Committee, a scientific panel commissioned by the City of Portland in 1977 to review issues related to Bull Run.
In 1973, Joseph Miller, Jr., a retired Portland physician, sued the Forest Service, claiming that its logging violated the Bull Run Trespass Act. In 1976, U.S. District Judge James M. Burns agreed, and logging was halted. Shortly thereafter, Congress rescinded the Bull Run Trespass Act and replaced it with the Bull Run Watershed Management Act of 1977, which created the Bull Run Watershed Management Unit (BRWMU) (replacing the Bull Run Reserve) and legalized further Bull Run logging unless it could be shown to reduce water quality. Logging and the debate about logging continued. In 1994 about 75 percent of the BRWMU was made into a reserve for protecting the northern spotted owl and other species dependent on old-growth forests. In February 1996, runoff from unusually heavy rains in the watershed washed so much eroded soil into the Bull Run storage reservoirs that the City had to shut down the Bull Run supply and switch during the crisis to its emergency supply from a well field along the Columbia River. Later in 1996, Congress passed the Oregon Resources Conservation Act, which prohibited logging on all Forest Service lands within the Bull Run water supply drainage and another 3,500 acres (14 km²) of land that drained to the lower Bull Run River. In 2001, the Little Sandy Act extended the prohibitions to the entire BRWMU and public lands along the Little Sandy River.
Between 1958 and 1993, when the last timber-cutting took place in the BRWMU, about 14,500 acres (59 km²), roughly 22 percent of the water supply drainage, were logged. Since then, to reduce erosion from the outmoded logging infrastructure, the Forest Service and the water bureau have been decommissioning parts of the Bull Run forest road network, which had grown to 346 miles (557 km). By autumn 2008, they had closed 78 miles (126 km) of roads, were dismantling another 63 miles (101 km), and were removing 245 culverts.
Bull Run River (Oregon)