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• 1. [Article] Historical changes in stream habitats in the Columbia River basin

  Knowledge of how stream habitats change over time in natural and human-influenced ecosystems at large, regional scales is currently limited. A historical stream survey (1934-1945) was compared to current ...

  Citation × Citation Citation Abstract Copy Title: Historical changes in stream habitats in the Columbia River basin Author: McIntosh, Bruce A. Knowledge of how stream habitats change over time in natural and human-influenced ecosystems at large, regional scales is currently limited. A historical stream survey (1934-1945) was compared to current surveys to assess changes in poo1 habitats in the Columbia River basin. Streams from across the basin, representing a wide range of geologies, stream sizes and land-use histories, were used to evaluate habitat change. We classified streams as managed or unmanaged, based on their land-use histories. Managed basins were watersheds managed predominantly for multiple-use (e.g., timber harvest, livestock grazing) and unmanaged basins were minimally affected by human disturbance (e.g., wilderness/roadless areas). The quantity and quality of pool habitats increased or remained the same in unmanaged streams, and decreased in managed streams since the 1930s. Despite differences in stream size and land-use history, the magnitude and direction of theses changes were consistent. In addition, the decrease in pool habitats did not differ between public and private lands. Ecoregions were used to assess regional patterns to these changes. Our analysis showed that pool habitats decreased in all Ecoregions except the North Cascades Ecoregion. Regional land-use histories were documented for the study streams. The overgrazing of most rangelands had been documented by 1900. Grazing practices began to change after 1930, but current information suggests that while uplands have improved, riparian areas have not. By World War II, stream habitats had been affected by the loss of riparian vegetation, large woody debris, and aquatic habitats due to splash dams, log drives, and riparian timber harvest. Timber harvest expanded to the uplands after World War II, as the demand for timber expanded. Rapidly developing road networks increased runoff and sedimentation, which continued the impact of timber harvest on already damaged stream ecosystems. Almost 90% of managed streams had roads along the channel or within the floodplain. "Stream improvements," such as channelization and stream cleaning, also affected stream ecosystems. We concluded that the chronic and persistent effects of land-use practices had simplified stream channels and reduced habitat complexity in most managed watersheds in the Columbia River basin. Title: Historical changes in stream habitats in the Columbia River basin Author: McIntosh, Bruce A. Knowledge of how stream habitats change over time in natural and human-influenced ecosystems at large, regional scales is currently limited. A historical stream survey (1934-1945) was compared to current surveys to assess changes in poo1 habitats in the Columbia River basin. Streams from across the basin, representing a wide range of geologies, stream sizes and land-use histories, were used to evaluate habitat change. We classified streams as managed or unmanaged, based on their land-use histories. Managed basins were watersheds managed predominantly for multiple-use (e.g., timber harvest, livestock grazing) and unmanaged basins were minimally affected by human disturbance (e.g., wilderness/roadless areas). The quantity and quality of pool habitats increased or remained the same in unmanaged streams, and decreased in managed streams since the 1930s. Despite differences in stream size and land-use history, the magnitude and direction of theses changes were consistent. In addition, the decrease in pool habitats did not differ between public and private lands. Ecoregions were used to assess regional patterns to these changes. Our analysis showed that pool habitats decreased in all Ecoregions except the North Cascades Ecoregion. Regional land-use histories were documented for the study streams. The overgrazing of most rangelands had been documented by 1900. Grazing practices began to change after 1930, but current information suggests that while uplands have improved, riparian areas have not. By World War II, stream habitats had been affected by the loss of riparian vegetation, large woody debris, and aquatic habitats due to splash dams, log drives, and riparian timber harvest. Timber harvest expanded to the uplands after World War II, as the demand for timber expanded. Rapidly developing road networks increased runoff and sedimentation, which continued the impact of timber harvest on already damaged stream ecosystems. Almost 90% of managed streams had roads along the channel or within the floodplain. "Stream improvements," such as channelization and stream cleaning, also affected stream ecosystems. We concluded that the chronic and persistent effects of land-use practices had simplified stream channels and reduced habitat complexity in most managed watersheds in the Columbia River basin. Close

• 2. [Article] Historical changes in anadromous fish habitat in the Upper Grande Ronde River, Oregon, 1941-1990

  The U.S. Bureau of Fisheries (now National Marine Fisheries Service) conducted stream habitat surveys in the Upper Grande Ronde River Basin in 1941. This survey was part of an extensive inventory of stream ...

  Citation × Citation Citation Abstract Copy Title: Historical changes in anadromous fish habitat in the Upper Grande Ronde River, Oregon, 1941-1990 Author: McIntosh, Bruce A. The U.S. Bureau of Fisheries (now National Marine Fisheries Service) conducted stream habitat surveys in the Upper Grande Ronde River Basin in 1941. This survey was part of an extensive inventory of stream habitat conditions for anadromous salmonids (Oncorhynchus spp.) throughout the Columbia River Basin. The survey systematically inventoried 158 km of streams within the 3000 km2 watershed. Stream habitat was degraded from land-use activities (riparian timber harvest, splash dams, stream channelization, livestock grazing, and mining) prior to the 1941 survey. A 1990 resurvey determined how stream habitat conditions had continued to change. The historical survey and the 1990 resurvey inventoried streams according to pool and substrate characteristics. Pools were classified by size and depth criteria, while substrate was divided into size-classes. Losses in total pools/km (> 20m2 area and > 0.5 m depth) ranged from 43 to 83% (mean = 65%, 12.2 to 4.31km), while the loss in large pools/km (> 20m2 and > 1.0 m depth) ranged from 20 to 89% (mean = 68%, 6.2 to 2.0/1cm) for individual streams. The loss of variability in pool frequencies from 1941 to 1990 (total pools/km a2 = 43.9 to 2.8, large pools/km a2 = 23.2 to 3.2) demonstrates that stream channels have become less diverse. Classifying streams by reach types indicated that the decline in pool frequencies was not significantly related to geomorphic constraints. Substrate composition appears to have shifted toward smaller size-classes, with an increase in fine sediments (< 6mm) in the headwaters. Livestock grazing declined 78% (229,000 to 51,000 aum) from 1911 to 1990, while annual timber harvest increased 172% (36 to 98 mmbf) from the pre-survey period (1896-1940) to the post-survey period (1940-1990). Road densities have increased concurrent with timber harvest, currently averaging 4 miles/mile2. Base discharge has increased 51% (18.5 to 28.0 cfs), while there has been a 27% decrease in annual precipitation (22.0" to 16.0") and snowpack (April 1 water equivalent) (15.0" to 10.5") from 1941 to 1990. In an era of presumably improving management (1941-1990), large-scale losses in the fish habitat necessary for the continued viability of resident and anadromous fish populations continued to occur. Title: Historical changes in anadromous fish habitat in the Upper Grande Ronde River, Oregon, 1941-1990 Author: McIntosh, Bruce A. The U.S. Bureau of Fisheries (now National Marine Fisheries Service) conducted stream habitat surveys in the Upper Grande Ronde River Basin in 1941. This survey was part of an extensive inventory of stream habitat conditions for anadromous salmonids (Oncorhynchus spp.) throughout the Columbia River Basin. The survey systematically inventoried 158 km of streams within the 3000 km2 watershed. Stream habitat was degraded from land-use activities (riparian timber harvest, splash dams, stream channelization, livestock grazing, and mining) prior to the 1941 survey. A 1990 resurvey determined how stream habitat conditions had continued to change. The historical survey and the 1990 resurvey inventoried streams according to pool and substrate characteristics. Pools were classified by size and depth criteria, while substrate was divided into size-classes. Losses in total pools/km (> 20m2 area and > 0.5 m depth) ranged from 43 to 83% (mean = 65%, 12.2 to 4.31km), while the loss in large pools/km (> 20m2 and > 1.0 m depth) ranged from 20 to 89% (mean = 68%, 6.2 to 2.0/1cm) for individual streams. The loss of variability in pool frequencies from 1941 to 1990 (total pools/km a2 = 43.9 to 2.8, large pools/km a2 = 23.2 to 3.2) demonstrates that stream channels have become less diverse. Classifying streams by reach types indicated that the decline in pool frequencies was not significantly related to geomorphic constraints. Substrate composition appears to have shifted toward smaller size-classes, with an increase in fine sediments (< 6mm) in the headwaters. Livestock grazing declined 78% (229,000 to 51,000 aum) from 1911 to 1990, while annual timber harvest increased 172% (36 to 98 mmbf) from the pre-survey period (1896-1940) to the post-survey period (1940-1990). Road densities have increased concurrent with timber harvest, currently averaging 4 miles/mile2. Base discharge has increased 51% (18.5 to 28.0 cfs), while there has been a 27% decrease in annual precipitation (22.0" to 16.0") and snowpack (April 1 water equivalent) (15.0" to 10.5") from 1941 to 1990. In an era of presumably improving management (1941-1990), large-scale losses in the fish habitat necessary for the continued viability of resident and anadromous fish populations continued to occur. Close

• 3. [Article] The influence of contemporary forest harvesting on summer stream temperatures in headwater streams of Hinkle Creek, Oregon

  Stream temperature is a water quality parameter that directly influences the quality of aquatic habitat, particularly for cold-water species such as Pacific salmonids. Forest harvesting adjacent to a stream ...

  Citation × Citation Citation Abstract Copy Title: The influence of contemporary forest harvesting on summer stream temperatures in headwater streams of Hinkle Creek, Oregon Author: Kibler, Kelly Maren Stream temperature is a water quality parameter that directly influences the quality of aquatic habitat, particularly for cold-water species such as Pacific salmonids. Forest harvesting adjacent to a stream can increase the amount of solar radiation the stream receives, which can elevate stream temperatures and impair aquatic habitat. Oregon Forest Practice Rules mandate that forest operators leave Riparian Management Areas (RMAs) adjacent to streams in order to minimize the water quality impacts from forest harvesting. However, RMAs that contain overstory merchantable conifers are not required for small non-fish-bearing streams in Oregon, thus there is potential for increases in stream temperature to occur in headwater streams after harvesting. There is concern that increases in stream temperatures and changes to onsite processes in non-fish-bearing, headwater streams may propagate downstream and impair habitat in fish-bearing streams. The objectives of the following work are to assess the effects of contemporary forest management practices on stream temperatures of small non-fish-bearing headwater streams and to develop new knowledge regarding the physical processes that control reach-level stream temperature patterns. Summer stream temperatures were measured for five years in six headwater streams in the Hinkle Creek basin in southern Oregon. After four years, four of the streams were harvested and vegetated RMAs were not left between the streams and harvest units. The watersheds of the two remaining streams were not disturbed. Post-harvest stream temperatures were monitored for one year in all six streams. Each harvested stream was paired with one unharvested stream and regression relationships for maximum, minimum and mean daily stream temperatures were developed. Changes to temperatures of harvested streams were detected by comparing the mean pre-harvest regression relationship to the mean post-harvest relationship. Change detection analyses that considered the mean response among all four harvested streams indicated that maximum daily stream temperatures did not increase after harvesting, but that minimum and mean daily temperatures decreased significantly after harvesting. Additionally, diel stream temperature fluctuations were significantly greater one year after harvesting. Pre- and post-harvest surveys of canopy closure in the harvested and unharvested streams were completed in order to compare levels of stream shading before and after harvest. The post-harvest survey quantified canopy closure from remaining overstory vegetation as well as from logging slash that partially covered the harvested streams. The surveys indicated that mean overstory canopy closure in the harvested streams decreased by 84% as a result of the harvest, but as the logging slash provided considerable cover, total canopy closure decreased by only 20%. It is possible that the logging slash effectively attenuated solar radiation and prevented extreme temperature increases in the harvested streams. However, it is likely that streamflow increased after harvesting and that the increased streamflow also prevented increases to maximum temperatures and contributed to lower minimum and mean stream temperatures. Title: The influence of contemporary forest harvesting on summer stream temperatures in headwater streams of Hinkle Creek, Oregon Author: Kibler, Kelly Maren Stream temperature is a water quality parameter that directly influences the quality of aquatic habitat, particularly for cold-water species such as Pacific salmonids. Forest harvesting adjacent to a stream can increase the amount of solar radiation the stream receives, which can elevate stream temperatures and impair aquatic habitat. Oregon Forest Practice Rules mandate that forest operators leave Riparian Management Areas (RMAs) adjacent to streams in order to minimize the water quality impacts from forest harvesting. However, RMAs that contain overstory merchantable conifers are not required for small non-fish-bearing streams in Oregon, thus there is potential for increases in stream temperature to occur in headwater streams after harvesting. There is concern that increases in stream temperatures and changes to onsite processes in non-fish-bearing, headwater streams may propagate downstream and impair habitat in fish-bearing streams. The objectives of the following work are to assess the effects of contemporary forest management practices on stream temperatures of small non-fish-bearing headwater streams and to develop new knowledge regarding the physical processes that control reach-level stream temperature patterns. Summer stream temperatures were measured for five years in six headwater streams in the Hinkle Creek basin in southern Oregon. After four years, four of the streams were harvested and vegetated RMAs were not left between the streams and harvest units. The watersheds of the two remaining streams were not disturbed. Post-harvest stream temperatures were monitored for one year in all six streams. Each harvested stream was paired with one unharvested stream and regression relationships for maximum, minimum and mean daily stream temperatures were developed. Changes to temperatures of harvested streams were detected by comparing the mean pre-harvest regression relationship to the mean post-harvest relationship. Change detection analyses that considered the mean response among all four harvested streams indicated that maximum daily stream temperatures did not increase after harvesting, but that minimum and mean daily temperatures decreased significantly after harvesting. Additionally, diel stream temperature fluctuations were significantly greater one year after harvesting. Pre- and post-harvest surveys of canopy closure in the harvested and unharvested streams were completed in order to compare levels of stream shading before and after harvest. The post-harvest survey quantified canopy closure from remaining overstory vegetation as well as from logging slash that partially covered the harvested streams. The surveys indicated that mean overstory canopy closure in the harvested streams decreased by 84% as a result of the harvest, but as the logging slash provided considerable cover, total canopy closure decreased by only 20%. It is possible that the logging slash effectively attenuated solar radiation and prevented extreme temperature increases in the harvested streams. However, it is likely that streamflow increased after harvesting and that the increased streamflow also prevented increases to maximum temperatures and contributed to lower minimum and mean stream temperatures. Close

• 4. [Article] Distribution and juvenile ecology of bull trout (Salvelinus confluentus) in the Cascade Mountains

  Distribution and juvenile habitat use of bull trout (Salvelinus confluentus) were surveyed in selected areas of the Upper Willamette, Deschutes, upper Yakima, and upper Cedar River basins in Oregon and Washington ...

  Citation × Citation Citation Abstract Copy Title: Distribution and juvenile ecology of bull trout (Salvelinus confluentus) in the Cascade Mountains Author: Goetz, Frederick Allen Distribution and juvenile habitat use of bull trout (Salvelinus confluentus) were surveyed in selected areas of the Upper Willamette, Deschutes, upper Yakima, and upper Cedar River basins in Oregon and Washington from 1989 to 1991, using day snorkeling, night snorkeling, and electrofishing. These methods were selected after a preliminary diel streamside study of juvenile bull trout showed fry (age 0) counts were significantly higher (P<0.00l) during the day, while counts of juvenile fish (age 1 and 2) were significantly higher (P<0.00l) at night. The highest counts of juveniles occurred during a "quiet period" immediately after dusk, during which time fish were inactive, out of cover, and easily counted with underwater flashlights. In a comparison of four sampling methods on Jack Creek, electrofishing was significantly correlated (P<0.05) with day (r=0.8l) and night (r=0.89) snorkeling counts, but not with streambank counts. In a comparison of day and night snorkeling in 10 streams, total density estimates were significantly greater (P<0.0l) for night snorkeling than day. The diel study and sampling methods comparison suggested surveys of distribution and habitat use of bull trout should include night surveys as well as day. Distribution surveys found that, except for one stream, juvenile bull trout were found only in, or near, spring-fed areas created by recent lava flows. Presence of bull trout in a stream was related to cold groundwater temperatures, as they were not found in streams with temperatures above 14°C. Distribution of bull trout in Oregon and Washington followed a pattern of decreasing elevation with increasing latitude and longitude(Ra=-0.9l6) Presence at lower than expected elevations were explained when groundwater temperatures were predicted from mean annual air temperatures. Actual water temperatures for these spring-fed streams were significantly lower (p<0.00l) than predicted based on elevation, latitude, and longitude. Comparison of historical distribution of bull trout showed extant bull trout were found in the Willamette and Deschutes River Basins of Oregon, respectively, in only 26.2 and 56.2% of their former ranges. Factors associated with bull trout demise in Oregon Cascade streams were (1) isolation and inundation of spring-fed stream habitat by water control structures, (2) introduction of brook trout and brown trout, and (3) large flood events and habitat degradation. Juvenile habitat use was analyzed at the macrohabitat (habitat unit) level in five river basins. Diel and seasonal microhabitat use was also documented for one spring-fed stream, Jack Creek. There was a clear difference in habitat use day and night, associated with the low water temperature of the spring-fed streams (mean=8.0°C). All habitat unit types (pool, riffle, glide, side channel) were used day and night, but bull trout only elected to use side channels in both time periods. Bull trout were found at night in (1) a higher percentage of habitat units, (2) in higher densities by unit, and (3) in increasing numbers with increasing habitat unit area. In Jack Creek, bull trout elected to use shallow water depths, low mean velocities, instream woody debris, and small substrates. Title: Distribution and juvenile ecology of bull trout (Salvelinus confluentus) in the Cascade Mountains Author: Goetz, Frederick Allen Distribution and juvenile habitat use of bull trout (Salvelinus confluentus) were surveyed in selected areas of the Upper Willamette, Deschutes, upper Yakima, and upper Cedar River basins in Oregon and Washington from 1989 to 1991, using day snorkeling, night snorkeling, and electrofishing. These methods were selected after a preliminary diel streamside study of juvenile bull trout showed fry (age 0) counts were significantly higher (P<0.00l) during the day, while counts of juvenile fish (age 1 and 2) were significantly higher (P<0.00l) at night. The highest counts of juveniles occurred during a "quiet period" immediately after dusk, during which time fish were inactive, out of cover, and easily counted with underwater flashlights. In a comparison of four sampling methods on Jack Creek, electrofishing was significantly correlated (P<0.05) with day (r=0.8l) and night (r=0.89) snorkeling counts, but not with streambank counts. In a comparison of day and night snorkeling in 10 streams, total density estimates were significantly greater (P<0.0l) for night snorkeling than day. The diel study and sampling methods comparison suggested surveys of distribution and habitat use of bull trout should include night surveys as well as day. Distribution surveys found that, except for one stream, juvenile bull trout were found only in, or near, spring-fed areas created by recent lava flows. Presence of bull trout in a stream was related to cold groundwater temperatures, as they were not found in streams with temperatures above 14°C. Distribution of bull trout in Oregon and Washington followed a pattern of decreasing elevation with increasing latitude and longitude(Ra=-0.9l6) Presence at lower than expected elevations were explained when groundwater temperatures were predicted from mean annual air temperatures. Actual water temperatures for these spring-fed streams were significantly lower (p<0.00l) than predicted based on elevation, latitude, and longitude. Comparison of historical distribution of bull trout showed extant bull trout were found in the Willamette and Deschutes River Basins of Oregon, respectively, in only 26.2 and 56.2% of their former ranges. Factors associated with bull trout demise in Oregon Cascade streams were (1) isolation and inundation of spring-fed stream habitat by water control structures, (2) introduction of brook trout and brown trout, and (3) large flood events and habitat degradation. Juvenile habitat use was analyzed at the macrohabitat (habitat unit) level in five river basins. Diel and seasonal microhabitat use was also documented for one spring-fed stream, Jack Creek. There was a clear difference in habitat use day and night, associated with the low water temperature of the spring-fed streams (mean=8.0°C). All habitat unit types (pool, riffle, glide, side channel) were used day and night, but bull trout only elected to use side channels in both time periods. Bull trout were found at night in (1) a higher percentage of habitat units, (2) in higher densities by unit, and (3) in increasing numbers with increasing habitat unit area. In Jack Creek, bull trout elected to use shallow water depths, low mean velocities, instream woody debris, and small substrates. Close

• 5. [Article] Results and review of a riparian survey method used in eastern Oregon

  In the late 1970s, approximately 400 miles of streams were inventoried by the Prineville District of the Bureau of Land Management for in-stream and riparian condition. During the summer of 1994, the riparian ...

  Citation × Citation Citation Abstract Copy Title: Results and review of a riparian survey method used in eastern Oregon Author: Rasmussen, Christine G. In the late 1970s, approximately 400 miles of streams were inventoried by the Prineville District of the Bureau of Land Management for in-stream and riparian condition. During the summer of 1994, the riparian portion of the survey was repeated on 17 of the original streams miles, contained within 11 stream sections where grazing strategies had been altered. This project was a case study designed to evaluate efficiency of the original methods and identify factors involved in individual stream responses. The streams selected to be resurveyed varied in community types present, gradient, elevation, grazing system, disturbance history, influence of beaver, and restoration efforts. Community types were identified by their major components (grass-shrub, sedge-rush) and measured for length and width. Length of stream bank damage was estimated and causes noted. Stream sections were surveyed between matching points for the 1976-78 and 1994 surveys. Most streams had increases in riparian area and decreases in bank damage and lengths of cutbanks, suggesting an upward trend in condition. The bank damage, riparian area, and community identification portions of the survey were identified as useful though composition measurements were determined to be less dependable and repeatable. Title: Results and review of a riparian survey method used in eastern Oregon Author: Rasmussen, Christine G. In the late 1970s, approximately 400 miles of streams were inventoried by the Prineville District of the Bureau of Land Management for in-stream and riparian condition. During the summer of 1994, the riparian portion of the survey was repeated on 17 of the original streams miles, contained within 11 stream sections where grazing strategies had been altered. This project was a case study designed to evaluate efficiency of the original methods and identify factors involved in individual stream responses. The streams selected to be resurveyed varied in community types present, gradient, elevation, grazing system, disturbance history, influence of beaver, and restoration efforts. Community types were identified by their major components (grass-shrub, sedge-rush) and measured for length and width. Length of stream bank damage was estimated and causes noted. Stream sections were surveyed between matching points for the 1976-78 and 1994 surveys. Most streams had increases in riparian area and decreases in bank damage and lengths of cutbanks, suggesting an upward trend in condition. The bank damage, riparian area, and community identification portions of the survey were identified as useful though composition measurements were determined to be less dependable and repeatable. Close

• 6. [Article] Hydrologic integration of forest roads with stream networks in two basins, western Cascades, Oregon

  This study assessed how logging-access roads may have contributed to observed historical increases in peak discharges associated with small and large logged basins in the western Cascades of Oregon. The ...

  Citation × Citation Citation Abstract Copy Title: Hydrologic integration of forest roads with stream networks in two basins, western Cascades, Oregon Author: Wemple, Beverly C. This study assessed how logging-access roads may have contributed to observed historical increases in peak discharges associated with small and large logged basins in the western Cascades of Oregon. The study was conducted on the Lookout Creek (62km²) and the upper Blue River (118km²) basins. Potential road effects on hydrology were examined using a combination of field surveys and spatial modeling with a geographic information system (GIS). Road networks were similar in both basins with respect to hillslope position, orientation, and stream crossings, but roads in Blue River were constructed one or two decades later than roads in Lookout Creek. A total of 20% (62 km) of the road length was sampled to assess routing of surface flow, using 31 2-km transects stratified by decade of construction and hillslope position. Along each transect, ditches and culvert outlets were examined and this information used to predict the probable routing of water to (1) existing stream channels, (2) newly eroded gullies downslope of culvert outlets, or (3) subsurface flow. Nearly 60% of the surveyed road length appeared to route water directly to stream channels or into gullies. Over time, the length of road connected to stream crossings has decreased, while the length of road discharging runoff that reinfiltrates to subsurface flow has increased, as roads have progressed up hillslopes and onto ridges in Lookout Creek and Blue River. The relatively constant proportion of the road network draining to gullies over time suggests that roads have the potential to become integrated into stream networks, even when constructed on unchannelled hillslope positions. An extended stream network, assumed to exist under storm conditions, was simulated for the basins using a digital elevation model. Although gullies and ditches differ from natural channels, extrapolation of field surveys using the GIS suggested that roads might extend the stream network by as much as 40% during storm events. It is hypothesized that such an effect could decrease the time of concentration of stormflow and contribute to higher peak discharges observed after clearcutting and road construction in these basins. Differences in the magnitude of road effects on peak flow generation may occur among road systems according to hillslope position of roads, road age, soil saturation, geologic substrate, and climate. These differences may explain the range of observed results from paired-basin studies examining road effects on hydrologic response. Title: Hydrologic integration of forest roads with stream networks in two basins, western Cascades, Oregon Author: Wemple, Beverly C. This study assessed how logging-access roads may have contributed to observed historical increases in peak discharges associated with small and large logged basins in the western Cascades of Oregon. The study was conducted on the Lookout Creek (62km²) and the upper Blue River (118km²) basins. Potential road effects on hydrology were examined using a combination of field surveys and spatial modeling with a geographic information system (GIS). Road networks were similar in both basins with respect to hillslope position, orientation, and stream crossings, but roads in Blue River were constructed one or two decades later than roads in Lookout Creek. A total of 20% (62 km) of the road length was sampled to assess routing of surface flow, using 31 2-km transects stratified by decade of construction and hillslope position. Along each transect, ditches and culvert outlets were examined and this information used to predict the probable routing of water to (1) existing stream channels, (2) newly eroded gullies downslope of culvert outlets, or (3) subsurface flow. Nearly 60% of the surveyed road length appeared to route water directly to stream channels or into gullies. Over time, the length of road connected to stream crossings has decreased, while the length of road discharging runoff that reinfiltrates to subsurface flow has increased, as roads have progressed up hillslopes and onto ridges in Lookout Creek and Blue River. The relatively constant proportion of the road network draining to gullies over time suggests that roads have the potential to become integrated into stream networks, even when constructed on unchannelled hillslope positions. An extended stream network, assumed to exist under storm conditions, was simulated for the basins using a digital elevation model. Although gullies and ditches differ from natural channels, extrapolation of field surveys using the GIS suggested that roads might extend the stream network by as much as 40% during storm events. It is hypothesized that such an effect could decrease the time of concentration of stormflow and contribute to higher peak discharges observed after clearcutting and road construction in these basins. Differences in the magnitude of road effects on peak flow generation may occur among road systems according to hillslope position of roads, road age, soil saturation, geologic substrate, and climate. These differences may explain the range of observed results from paired-basin studies examining road effects on hydrologic response. Close

• 7. [Article] Year 2000 Timber Sales - Confederated Tribes on Grand Ronde : Biological Opinion

  The Natural Resources Division (NRD) of the Confederated Tribes of Grand Ronde (CTGR), in cooperation with the Bureau of Indian Affairs (BIA), proposes the regeneration harvest and commercial thinning ...

  Citation × Citation Citation Abstract Copy Title: Year 2000 Timber Sales - Confederated Tribes on Grand Ronde : Biological Opinion The Natural Resources Division (NRD) of the Confederated Tribes of Grand Ronde (CTGR), in cooperation with the Bureau of Indian Affairs (BIA), proposes the regeneration harvest and commercial thinning of four timber sales on the Reservation of The Confederated Tribes of Grand Ronde (CTGR). The CTGR has a 20-year management agreement with the BIA. For the purposes of this consultation the BIA is the action agency. The proposed timber harvest units are in the South Yamhill River subbasin, which supports two species listed by the National Marine Fisheries Service (NMFS) as threatened under the Federal Endangered Species Act (ESA). Upper Willamette River (UWR) chinook salmon (Oncorhynchus tshawytscha) were listed as threatened under the ESA on May 24, 1999. Upper Willamette River (UWR) steelhead (Oncorhynchus mykiss) were listed as threatened under the ESA on March 25, 1999. Critical habitat for both of these species was designated on February 16, 2000 (effective on March 17, 2000). According to the BA, UWR chinook do not currently reside in the action area and there is no recorded data indicating they were present historically. The nearest known occurrence of UWR chinook is near the confluence of Salt creek and the South Yamhill River, over 40 stream miles from the Reservation. Juvenile UWR steelhead reside within the action area and are known to occur in streams on the reservation. Based on the presence of juveniles, CTGR staff suspect that adult UWR steelhead spawn in streams on the Reservation, although little spawning survey work has been done. Title: Year 2000 Timber Sales - Confederated Tribes on Grand Ronde : Biological Opinion The Natural Resources Division (NRD) of the Confederated Tribes of Grand Ronde (CTGR), in cooperation with the Bureau of Indian Affairs (BIA), proposes the regeneration harvest and commercial thinning of four timber sales on the Reservation of The Confederated Tribes of Grand Ronde (CTGR). The CTGR has a 20-year management agreement with the BIA. For the purposes of this consultation the BIA is the action agency. The proposed timber harvest units are in the South Yamhill River subbasin, which supports two species listed by the National Marine Fisheries Service (NMFS) as threatened under the Federal Endangered Species Act (ESA). Upper Willamette River (UWR) chinook salmon (Oncorhynchus tshawytscha) were listed as threatened under the ESA on May 24, 1999. Upper Willamette River (UWR) steelhead (Oncorhynchus mykiss) were listed as threatened under the ESA on March 25, 1999. Critical habitat for both of these species was designated on February 16, 2000 (effective on March 17, 2000). According to the BA, UWR chinook do not currently reside in the action area and there is no recorded data indicating they were present historically. The nearest known occurrence of UWR chinook is near the confluence of Salt creek and the South Yamhill River, over 40 stream miles from the Reservation. Juvenile UWR steelhead reside within the action area and are known to occur in streams on the reservation. Based on the presence of juveniles, CTGR staff suspect that adult UWR steelhead spawn in streams on the Reservation, although little spawning survey work has been done. Close

• 8. [Article] Is the past present? Historical splash-dam mapping and stream disturbance detection in the Oregon Coastal Province

  Severe scouring from splash damming was one of the earliest reported forms of widespread anthropogenic disturbance in streams of the Pacific Northwest, USA. Splash damming was a common method of log transport ...

  Citation × Citation Citation Abstract Copy Title: Is the past present? Historical splash-dam mapping and stream disturbance detection in the Oregon Coastal Province Author: Miller, Rebecca R. Severe scouring from splash damming was one of the earliest reported forms of widespread anthropogenic disturbance in streams of the Pacific Northwest, USA. Splash damming was a common method of log transport in western Oregon from the 1880s through the 1950s. Before being released in large freshets to downstream lumber mills, water and logs were stored in reservoirs behind splash dams. Further protocol called for dynamiting downstream obstacles such as large boulders and natural logjams. In recent literature, the legacy effect of historical splash damming is proposed as contributing to currently poor habitat conditions for lotic species, such as Pacific salmon (Oncorhynchus spp.), but this has never been formally evaluated at a regional scale. In this study, all known splash-dam sites and log drives in western Oregon were recorded in a geo-database and mapped in ArcGIS 9.3 at the 1:24,000 scale. Splash-dam sites were located through intense archival, historical aerial photograph and field searches. The final splash-dam map was overlaid with regionally available continuous and probabilistic stream surveys. After accounting for basin area and channel slope, in-channel variables were compared between reaches upstream and downstream of splash dams (within-basin analysis) and between reaches in splashed and not-splashed basins (among-basin analysis). Only data from sites located in a forested land cover and sedimentary rock type in the Oregon Coastal Province were analyzed. A significant difference (α = 0.1) was seen in either within- or among-basin analyses for each evaluated category of in-channel variable (geomorphology, substrates, pools, and channel complexity). Both analyses demonstrated significantly more bedrock and fewer deep pools in splashed reaches. In the among-basin analysis, three times fewer pieces of key large wood were found in splashed reaches (p = 0.07). Many of the in-channel variables that demonstrated significant differences are regarded as indicators of salmon habitat quality. This is the first regional study to document that splash-dam legacy effects still persist on evaluated stream reaches 50-130 years after the practice ceased. Further, I detected a splash-damming signal in widely used regional monitoring datasets, which suggests that legacy effects should be considered in future applications of these datasets. Splash-damming impacts are pervasive and persistent throughout the Oregon Coastal Province; consequently, extensive and intensive restoration measures may be necessary to accelerate recovery of certain stream habitat characteristics in streams where splash damming and log drives occurred. This study demonstrates the importance of including archival information in modern-day studies, and that history can account for significant variation in the stream environment. Title: Is the past present? Historical splash-dam mapping and stream disturbance detection in the Oregon Coastal Province Author: Miller, Rebecca R. Severe scouring from splash damming was one of the earliest reported forms of widespread anthropogenic disturbance in streams of the Pacific Northwest, USA. Splash damming was a common method of log transport in western Oregon from the 1880s through the 1950s. Before being released in large freshets to downstream lumber mills, water and logs were stored in reservoirs behind splash dams. Further protocol called for dynamiting downstream obstacles such as large boulders and natural logjams. In recent literature, the legacy effect of historical splash damming is proposed as contributing to currently poor habitat conditions for lotic species, such as Pacific salmon (Oncorhynchus spp.), but this has never been formally evaluated at a regional scale. In this study, all known splash-dam sites and log drives in western Oregon were recorded in a geo-database and mapped in ArcGIS 9.3 at the 1:24,000 scale. Splash-dam sites were located through intense archival, historical aerial photograph and field searches. The final splash-dam map was overlaid with regionally available continuous and probabilistic stream surveys. After accounting for basin area and channel slope, in-channel variables were compared between reaches upstream and downstream of splash dams (within-basin analysis) and between reaches in splashed and not-splashed basins (among-basin analysis). Only data from sites located in a forested land cover and sedimentary rock type in the Oregon Coastal Province were analyzed. A significant difference (α = 0.1) was seen in either within- or among-basin analyses for each evaluated category of in-channel variable (geomorphology, substrates, pools, and channel complexity). Both analyses demonstrated significantly more bedrock and fewer deep pools in splashed reaches. In the among-basin analysis, three times fewer pieces of key large wood were found in splashed reaches (p = 0.07). Many of the in-channel variables that demonstrated significant differences are regarded as indicators of salmon habitat quality. This is the first regional study to document that splash-dam legacy effects still persist on evaluated stream reaches 50-130 years after the practice ceased. Further, I detected a splash-damming signal in widely used regional monitoring datasets, which suggests that legacy effects should be considered in future applications of these datasets. Splash-damming impacts are pervasive and persistent throughout the Oregon Coastal Province; consequently, extensive and intensive restoration measures may be necessary to accelerate recovery of certain stream habitat characteristics in streams where splash damming and log drives occurred. This study demonstrates the importance of including archival information in modern-day studies, and that history can account for significant variation in the stream environment. Close

• 9. [Article] Nature in chains : the effects of Thomas Jefferson’s rectangular survey on a Pacific Northwest landscape

  Understanding the impact of humans on the environment has long been a topic of scholarly interest and debate. As environmental problems mount, accounts of historic ecological conditions and the factors ...

  Citation × Citation Citation Abstract Copy Title: Nature in chains : the effects of Thomas Jefferson’s rectangular survey on a Pacific Northwest landscape Author: Schweickert, Tina K. Understanding the impact of humans on the environment has long been a topic of scholarly interest and debate. As environmental problems mount, accounts of historic ecological conditions and the factors of change become increasingly useful. This study considers competing schools of interpretation about human impacts on ecological landscapes and develops a case study of one thirty-six square mile township in Oregon’s Waldo Hills. Built on evidence from 1851 surveyor notes, maps, journals, aerial photos, interviews, and contemporary environmental and ecological data, this study demonstrates a transformation from ecologically diverse ecosystems under the management of native peoples to ecologically depressed monoculture landscapes under industrialized agriculture. This thesis argues that the fundamental beliefs of human societies (i.e., worldviews) become expressed in the landscape. The nature-as-community view of the Kalapuya Indians resulted in a complex, curvilinear mosaic of prairie, savanna, and woodland. The individualized and rationalized view of the Euroamericans resulted in a simplified landscape of squared-off fields, channelized streams, and roads aligned to the survey grid. Thomas Jefferson’s rectangular survey, built on the ‘virtuous square’, is examined as a symbolic and tangible instrument of rapid expansion and exploitation across the American West. Understanding that worldviews become expressed in physical conditions may benefit those working to create sustainable futures; i.e., long-term and widespread ecological improvements will likely succeed only if society at large shares a fundamental belief in the value of healthy ecosystems. Title: Nature in chains : the effects of Thomas Jefferson’s rectangular survey on a Pacific Northwest landscape Author: Schweickert, Tina K. Understanding the impact of humans on the environment has long been a topic of scholarly interest and debate. As environmental problems mount, accounts of historic ecological conditions and the factors of change become increasingly useful. This study considers competing schools of interpretation about human impacts on ecological landscapes and develops a case study of one thirty-six square mile township in Oregon’s Waldo Hills. Built on evidence from 1851 surveyor notes, maps, journals, aerial photos, interviews, and contemporary environmental and ecological data, this study demonstrates a transformation from ecologically diverse ecosystems under the management of native peoples to ecologically depressed monoculture landscapes under industrialized agriculture. This thesis argues that the fundamental beliefs of human societies (i.e., worldviews) become expressed in the landscape. The nature-as-community view of the Kalapuya Indians resulted in a complex, curvilinear mosaic of prairie, savanna, and woodland. The individualized and rationalized view of the Euroamericans resulted in a simplified landscape of squared-off fields, channelized streams, and roads aligned to the survey grid. Thomas Jefferson’s rectangular survey, built on the ‘virtuous square’, is examined as a symbolic and tangible instrument of rapid expansion and exploitation across the American West. Understanding that worldviews become expressed in physical conditions may benefit those working to create sustainable futures; i.e., long-term and widespread ecological improvements will likely succeed only if society at large shares a fundamental belief in the value of healthy ecosystems. Close

• 10. [Article] Factors influencing pool morphology in Oregon coastal streams

  Pool morphology was surveyed in 19 stream sections within the central Oregon Coast Range. Pool locations, sizes, spacings, numbers, and factors affecting pool formation were determined for each stream ...

  Citation × Citation Citation Abstract Copy Title: Factors influencing pool morphology in Oregon coastal streams Author: Stack, William Robert Pool morphology was surveyed in 19 stream sections within the central Oregon Coast Range. Pool locations, sizes, spacings, numbers, and factors affecting pool formation were determined for each stream section. All sections were underlain by sedimentary rocks, had drainage areas ranging from 1.3 to 17.3 km², and had average water surface slopes from 0.5 to 5.6%. Stream sections were divided into two categories: (1) low timber harvest (<20% of watershed area harvested) and (2) high timber harvest (>45% of watershed area harvested). A "Rapid Bed Profile" (REP) technique was developed to measure residual pool characteristics in each stream section. The REP technique is a survey method that requires only thalweg depths and the average reach gradient. The technique was effective for classifying pools since it is objective, independent of flow, accurate, and time-efficient. Residual pool size characteristics (e.g., volume) for the low timber harvest stream sections were positively correlated to a power function of drainage area. Stream sections with beaver dams, especially those with at least 10% of their reach length in beaver-caused pools, typically had larger residual pools. Pool size characteristics for high timber harvest stream sections were not different from low timber harvest stream sections. The average spacing between residual pools was positively correlated to a power function of drainage area for the low timber harvest stream sections (a negative correlation was found between the number of pools and drainage area). High timber harvest stream sections may be associated with an increased spacing and a decreased number of pools for larger watersheds (i.e., greater than 8 km²). However, the potential effects of previous large storms, changes in timber management practices, and/or the small number of streams surveyed precluded a definitive conclusion. The frequency of occurrence of pool forming processes (e.g., plunge, deflection) was correlated with average water surface slope for the low timber harvest stream sections. The percentage of plunge and impoundment processes increased as water surface slope increased while the percentage of deflection and underflow processes decreased. Two high timber harvest streams had a higher percentage of plunge pools than expected based on the relationships established for the low timber harvest streams. The frequency of occurrence of wood and boulder pool forming elements was correlated with an index of stream power (drainage area times average water slope) for the low timber harvest stream sections. As the stream power index increased, the relative frequency of wood-formed pools decreased while boulder-formed pools increased. Wood and boulder combined, generally, made up 80% of the pool forming elements. The frequency of occurrence of pool forming elements was not different between low and high timber harvest stream sections. Title: Factors influencing pool morphology in Oregon coastal streams Author: Stack, William Robert Pool morphology was surveyed in 19 stream sections within the central Oregon Coast Range. Pool locations, sizes, spacings, numbers, and factors affecting pool formation were determined for each stream section. All sections were underlain by sedimentary rocks, had drainage areas ranging from 1.3 to 17.3 km², and had average water surface slopes from 0.5 to 5.6%. Stream sections were divided into two categories: (1) low timber harvest (<20% of watershed area harvested) and (2) high timber harvest (>45% of watershed area harvested). A "Rapid Bed Profile" (REP) technique was developed to measure residual pool characteristics in each stream section. The REP technique is a survey method that requires only thalweg depths and the average reach gradient. The technique was effective for classifying pools since it is objective, independent of flow, accurate, and time-efficient. Residual pool size characteristics (e.g., volume) for the low timber harvest stream sections were positively correlated to a power function of drainage area. Stream sections with beaver dams, especially those with at least 10% of their reach length in beaver-caused pools, typically had larger residual pools. Pool size characteristics for high timber harvest stream sections were not different from low timber harvest stream sections. The average spacing between residual pools was positively correlated to a power function of drainage area for the low timber harvest stream sections (a negative correlation was found between the number of pools and drainage area). High timber harvest stream sections may be associated with an increased spacing and a decreased number of pools for larger watersheds (i.e., greater than 8 km²). However, the potential effects of previous large storms, changes in timber management practices, and/or the small number of streams surveyed precluded a definitive conclusion. The frequency of occurrence of pool forming processes (e.g., plunge, deflection) was correlated with average water surface slope for the low timber harvest stream sections. The percentage of plunge and impoundment processes increased as water surface slope increased while the percentage of deflection and underflow processes decreased. Two high timber harvest streams had a higher percentage of plunge pools than expected based on the relationships established for the low timber harvest streams. The frequency of occurrence of wood and boulder pool forming elements was correlated with an index of stream power (drainage area times average water slope) for the low timber harvest stream sections. As the stream power index increased, the relative frequency of wood-formed pools decreased while boulder-formed pools increased. Wood and boulder combined, generally, made up 80% of the pool forming elements. The frequency of occurrence of pool forming elements was not different between low and high timber harvest stream sections. Close