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• 21. [Article] Scenic photo of Myrtle Creek in the South Umpqua Watershed

  Myrtle Creek photo

  Citation × Citation Citation Abstract Copy Title: Scenic photo of Myrtle Creek in the South Umpqua Watershed Author: Partnership for the Umpqua Rivers Myrtle Creek photo Title: Scenic photo of Myrtle Creek in the South Umpqua Watershed Author: Partnership for the Umpqua Rivers Myrtle Creek photo Close

• 22. [Article] South Umpqua River Watershed assessment and action plan

  The introduction provides a general description of the watershed in terms of its natural and human-made features, ownership and current land uses, and the communities within the watershed. Information ...

  Citation × Citation Citation Abstract Copy Title: South Umpqua River Watershed assessment and action plan Author: Geyer, Nancy A. The introduction provides a general description of the watershed in terms of its natural and human-made features, ownership and current land uses, and the communities within the watershed. Information in sections 1.2 and 1.3 was compiled from the Oregon Watershed Assessment Manual (Watershed Professionals Network, 1999), the Lower South Umpqua Watershed Analysis (USDI Bureau of Land Management, 2000), the Myrtle Creek Watershed Analysis (Draft) (USDI Bureau of Land Management, 2002) and the Middle South Umpqua Watershed Analysis (USDI Bureau of Land Management, 1999). Additional information is from the following sources’ databases: The Oregon Climate Service, the US Census Bureau, and the Douglas County Assessor. Title: South Umpqua River Watershed assessment and action plan Author: Geyer, Nancy A. The introduction provides a general description of the watershed in terms of its natural and human-made features, ownership and current land uses, and the communities within the watershed. Information in sections 1.2 and 1.3 was compiled from the Oregon Watershed Assessment Manual (Watershed Professionals Network, 1999), the Lower South Umpqua Watershed Analysis (USDI Bureau of Land Management, 2000), the Myrtle Creek Watershed Analysis (Draft) (USDI Bureau of Land Management, 2002) and the Middle South Umpqua Watershed Analysis (USDI Bureau of Land Management, 1999). Additional information is from the following sources’ databases: The Oregon Climate Service, the US Census Bureau, and the Douglas County Assessor. Close

• 23. [Article] The effects of hillslope and fluvial processes on particle size of the stream bed at the watershed, reach and within-reach scales in a fifth-order mountain stream

  This study addressed the effects of hilislope and fiuvial processes on spatial patterns of stream bed particle size at the watershed, reach and within-reach scales. The study was conducted in Lookout Creek ...

  Citation × Citation Citation Abstract Copy Title: The effects of hillslope and fluvial processes on particle size of the stream bed at the watershed, reach and within-reach scales in a fifth-order mountain stream Author: Lambert, Beth C. This study addressed the effects of hilislope and fiuvial processes on spatial patterns of stream bed particle size at the watershed, reach and within-reach scales. The study was conducted in Lookout Creek watershed, a fifth-order, 64 km2 basin in the Western Cascades mountains of Oregon. Stream bed particle size was measured at 25 sites on first- through fifth-order streams. Boulder density was measured from the headwaters of the mainstem of Lookout Creek to its mouth, approximately 16 kilometers of stream length. In Lookout Creek watershed, spatial patterns of particle size result from a hierarchy of hydraulic and hilislope controls. At the watershed scale, hydraulic controls explain around 50% of the variation in d50 and d84. Particle size is related to watershed-scale trends in stream power and stream competence. At the reach scale, debris flows and landslides leave a patchy signature on stream bed particle size. Patches of both high and low boulder density are associated with landslides. A peak in density is associated with a February 1996 debris flow. Hydraulic controls are less evident at this scale, although the degree of reach constraint may affect particle size in fourth- and fifth-order Lookout Creek. At the within-reach scale, hydraulic controls are responsible for around 20% of the observed particle size variation. The effects of the largest flood on record at Lookout Creek were documented at 7 sites that had been sampled before the flood. At the watershed scale, a fining in particle size was observed; this is consistent with the hypothesis that Lookout Creek has an armor layer which the flood disturbed. At the within-reach scale, changes in particle size appeared stochastic, and provided little information about the role of hydraulic controls at that scale. Title: The effects of hillslope and fluvial processes on particle size of the stream bed at the watershed, reach and within-reach scales in a fifth-order mountain stream Author: Lambert, Beth C. This study addressed the effects of hilislope and fiuvial processes on spatial patterns of stream bed particle size at the watershed, reach and within-reach scales. The study was conducted in Lookout Creek watershed, a fifth-order, 64 km2 basin in the Western Cascades mountains of Oregon. Stream bed particle size was measured at 25 sites on first- through fifth-order streams. Boulder density was measured from the headwaters of the mainstem of Lookout Creek to its mouth, approximately 16 kilometers of stream length. In Lookout Creek watershed, spatial patterns of particle size result from a hierarchy of hydraulic and hilislope controls. At the watershed scale, hydraulic controls explain around 50% of the variation in d50 and d84. Particle size is related to watershed-scale trends in stream power and stream competence. At the reach scale, debris flows and landslides leave a patchy signature on stream bed particle size. Patches of both high and low boulder density are associated with landslides. A peak in density is associated with a February 1996 debris flow. Hydraulic controls are less evident at this scale, although the degree of reach constraint may affect particle size in fourth- and fifth-order Lookout Creek. At the within-reach scale, hydraulic controls are responsible for around 20% of the observed particle size variation. The effects of the largest flood on record at Lookout Creek were documented at 7 sites that had been sampled before the flood. At the watershed scale, a fining in particle size was observed; this is consistent with the hypothesis that Lookout Creek has an armor layer which the flood disturbed. At the within-reach scale, changes in particle size appeared stochastic, and provided little information about the role of hydraulic controls at that scale. Close

• 24. [Article] Stormwater Solutions for Improving Water Quality: Supporting the Development of the Amazon Creek Initiative

  The Long Tom Watershed Council (LTWC) is a non-profit organization in Eugene, Oregon that serves to protect and enhance watershed health in the Long Tom River Basin. The Amazon Creek Initiative was launched ...

  Citation × Citation Citation Abstract Copy Title: Stormwater Solutions for Improving Water Quality: Supporting the Development of the Amazon Creek Initiative Author: Larson, Kristen M. The Long Tom Watershed Council (LTWC) is a non-profit organization in Eugene, Oregon that serves to protect and enhance watershed health in the Long Tom River Basin. The Amazon Creek Initiative was launched by the LTWC in 2011 as Oregon’s newest Pesticide Stewardship Partner. Goals of the initiative are to improve water quality and habitat function in Amazon Creek by encouraging voluntary retrofits of low-impact development (LID) and through outreach and education of pollution prevention practices. This internship involved a series of projects in support of the development of the Amazon Creek Initiative. Accomplishments included surface water sampling, stakeholder research, development of communication tools, creation of an LID cost calculator, site visits and assessments of pesticide retailers, and a review of national efforts to train pesticide retail staff in integrated pest management. This work supports the Amazon Creek Initiative as it moves towards implementation and provided diverse learning opportunities in non-profit and watershed council operations, communicating a scientific message, and low-impact development solutions to stormwater management. Title: Stormwater Solutions for Improving Water Quality: Supporting the Development of the Amazon Creek Initiative Author: Larson, Kristen M. The Long Tom Watershed Council (LTWC) is a non-profit organization in Eugene, Oregon that serves to protect and enhance watershed health in the Long Tom River Basin. The Amazon Creek Initiative was launched by the LTWC in 2011 as Oregon’s newest Pesticide Stewardship Partner. Goals of the initiative are to improve water quality and habitat function in Amazon Creek by encouraging voluntary retrofits of low-impact development (LID) and through outreach and education of pollution prevention practices. This internship involved a series of projects in support of the development of the Amazon Creek Initiative. Accomplishments included surface water sampling, stakeholder research, development of communication tools, creation of an LID cost calculator, site visits and assessments of pesticide retailers, and a review of national efforts to train pesticide retail staff in integrated pest management. This work supports the Amazon Creek Initiative as it moves towards implementation and provided diverse learning opportunities in non-profit and watershed council operations, communicating a scientific message, and low-impact development solutions to stormwater management. Close

• 25. [Article] Scaling hydrologic impacts from road segments to a small watershed

  The impact of forest roads on the hydrology of forested watersheds has long been studied. While forest roads have been reported to alter storm runoff at the road segment scale, the potential for changes ...

  Citation × Citation Citation Abstract Copy Title: Scaling hydrologic impacts from road segments to a small watershed Author: Royer, Timothy Adam The impact of forest roads on the hydrology of forested watersheds has long been studied. While forest roads have been reported to alter storm runoff at the road segment scale, the potential for changes to be detectable at the small watershed scale has been debated. The purpose of this study was to quantify the road affect at the road segment scale and estimate how those affects are expressed at the mouth of a watershed. This study took place in the McDonald-Dunn Research Forest located in the Oregon Coast Range near Corvallis, Oregon. Claire Creek, a small watershed within the Oak Creek Watershed, and two road segments with the associated inboard ditches and upslope contributing areas were selected to represent the roaded watershed. Runoff from both road segments enters small headwater streams at stream crossing culverts. Discharge was measured from the headwater streams and from the road segments at the stream crossing culvert for five storms during the winter of 2004 – 2005. Discharge was also measured at the mouth of Claire Creek, an adjacent roadless watershed, Finley Creek, and at a gauging station on Oak Creek near the boundary of the McDonald-Dunn Forest. The difference in time of occurrence of peakflows and the length of the stream between the culverts and the mouth of Claire Creek was used to estimate a ‘real’ travel time of the peakflows for all five storms. Kinematic wave equations were used to model travel times of peakflows from the culverts to the mouth of Claire Creek, with and without the influence of the road. At the road segment scale the road affect was detectable for changes in peakflow magnitude, quickflow, and total stormflow, but the affect of the road on changes in the timing of occurrence of the peakflow was inconsistent. At the watershed scale the road affect could not be calculated for changes in peakflow magnitude, quickflow, or total stormflow because of the unavailability of pre-road runoff data. The modeled travel time of peakflows that included discharge from the road were shorter than the modeled travel time of peakflows of stream discharge alone by less than 10 minutes for all five storms. The road effect on real travel times of peakflows was inconsistent and did not correlate to the magnitude of the increase at the road segment or at the mouth of the watershed. These findings agree with earlier studies that have reported a road affect on storm runoff at the road scale, and suggest that the road affect at the mouth of a watershed may not be detectable. The findings also suggest that other factors are influencing runoff at the mouth of a watershed more than the addition of ditch runoff at stream crossing culverts. Title: Scaling hydrologic impacts from road segments to a small watershed Author: Royer, Timothy Adam The impact of forest roads on the hydrology of forested watersheds has long been studied. While forest roads have been reported to alter storm runoff at the road segment scale, the potential for changes to be detectable at the small watershed scale has been debated. The purpose of this study was to quantify the road affect at the road segment scale and estimate how those affects are expressed at the mouth of a watershed. This study took place in the McDonald-Dunn Research Forest located in the Oregon Coast Range near Corvallis, Oregon. Claire Creek, a small watershed within the Oak Creek Watershed, and two road segments with the associated inboard ditches and upslope contributing areas were selected to represent the roaded watershed. Runoff from both road segments enters small headwater streams at stream crossing culverts. Discharge was measured from the headwater streams and from the road segments at the stream crossing culvert for five storms during the winter of 2004 – 2005. Discharge was also measured at the mouth of Claire Creek, an adjacent roadless watershed, Finley Creek, and at a gauging station on Oak Creek near the boundary of the McDonald-Dunn Forest. The difference in time of occurrence of peakflows and the length of the stream between the culverts and the mouth of Claire Creek was used to estimate a ‘real’ travel time of the peakflows for all five storms. Kinematic wave equations were used to model travel times of peakflows from the culverts to the mouth of Claire Creek, with and without the influence of the road. At the road segment scale the road affect was detectable for changes in peakflow magnitude, quickflow, and total stormflow, but the affect of the road on changes in the timing of occurrence of the peakflow was inconsistent. At the watershed scale the road affect could not be calculated for changes in peakflow magnitude, quickflow, or total stormflow because of the unavailability of pre-road runoff data. The modeled travel time of peakflows that included discharge from the road were shorter than the modeled travel time of peakflows of stream discharge alone by less than 10 minutes for all five storms. The road effect on real travel times of peakflows was inconsistent and did not correlate to the magnitude of the increase at the road segment or at the mouth of the watershed. These findings agree with earlier studies that have reported a road affect on storm runoff at the road scale, and suggest that the road affect at the mouth of a watershed may not be detectable. The findings also suggest that other factors are influencing runoff at the mouth of a watershed more than the addition of ditch runoff at stream crossing culverts. Close

• 26. [Article] Tiller Region assessment and action plan

  The introduction provides a general description of the Tiller Region in terms of its natural and human-made features, ownership and current land uses, and the communities within the region. Information ...

  Citation × Citation Citation Abstract Copy Title: Tiller Region assessment and action plan Author: Geyer, Nancy A. The introduction provides a general description of the Tiller Region in terms of its natural and human-made features, ownership and current land uses, and the communities within the region. Information in sections 1.2 and 1.3 was compiled from the Oregon Watershed Assessment Manual (Watershed Professionals Network, 1999), the Lower South Umpqua Watershed Analysis (USDI Bureau of Land Management, 2000), and the Myrtle Creek Watershed Analysis (Draft) (USDI Bureau of Land Management, 2002). Additional information is from the following sources’ databases and staff: the USDA Forest Service, the US Census Bureau, and the Douglas County Assessor. Title: Tiller Region assessment and action plan Author: Geyer, Nancy A. The introduction provides a general description of the Tiller Region in terms of its natural and human-made features, ownership and current land uses, and the communities within the region. Information in sections 1.2 and 1.3 was compiled from the Oregon Watershed Assessment Manual (Watershed Professionals Network, 1999), the Lower South Umpqua Watershed Analysis (USDI Bureau of Land Management, 2000), and the Myrtle Creek Watershed Analysis (Draft) (USDI Bureau of Land Management, 2002). Additional information is from the following sources’ databases and staff: the USDA Forest Service, the US Census Bureau, and the Douglas County Assessor. Close

• 27. [Article] Silver Creek subbasin watershed assessment

  Citation × Citation Citation Abstract Copy Title: Silver Creek subbasin watershed assessment Author: Street, Pamela, Harney County Watershed Council Title: Silver Creek subbasin watershed assessment Author: Street, Pamela, Harney County Watershed Council Close

• 28. [Article] Habitat selection of hatchery and wild juvenile salmonids in Eagle Creek Basin, Oregon

  To best manage Eagle Creek National Fish Hatchery and minimize any negative impacts that the current hatchery program may be having on Endangered Species Act-listed salmonids in the Eagle Creek Basin, ...

  Citation × Citation Citation Abstract Copy Title: Habitat selection of hatchery and wild juvenile salmonids in Eagle Creek Basin, Oregon Author: Brignon, William R. To best manage Eagle Creek National Fish Hatchery and minimize any negative impacts that the current hatchery program may be having on Endangered Species Act-listed salmonids in the Eagle Creek Basin, I determined if wild fish are being displaced from preferred habitats by hatchery salmonids Oncorhynchus spp. This thesis had two goals. The first goal was to determine the possible effect of hatchery smolts on resident salmonids. I determined the density and distribution of wild juvenile steelhead O. mykiss and coho salmon O. kisutch in Eagle Creek and North Fork Eagle Creek, Oregon. My first objective was to compare summer rearing densities and distributions of wild salmonids in Eagle Creek, which receives a release of hatchery fish, and North Fork Eagle Creek, which does not receive a release of hatchery fish. Next, I determined if residual hatchery winter steelhead were present in Eagle Creek and/or North Fork Eagle Creek and if so whether or not they have an impact on mesohabitat selection, distribution, and density of wild fish in Eagle Creek basin. By conducting a comprehensive snorkel survey I identified significantly higher densities (P < 0.05) of juvenile coho salmon rearing in North Fork Eagle Creek as compared to upper and lower Eagle Creek. Age 0 winter steelhead occurred in significantly higher densities (P < 0.05) in upper Eagle Creek compared to lower Eagle Creek and North Fork Eagle Creek. Residual hatchery steelhead were located only in Eagle Creek and found rearing in the same 15 mesohabitat units that contained the estimated majority of wild fish populations. Residual hatchery steelhead comprised 0.9% of the winter steelhead population (1.1% of age 0 winter steelhead and 9.3% of age 1 winter steelhead), and 2.2% of the coho salmon population estimated to be rearing in Eagle Creek. From these data it is unclear if residual hatchery steelhead are affecting densities, distributions, and mesohabitat selection of wild salmonids in the basin. However, while I was unable to detect any direct impacts of residual hatchery fish on the wild population, these results do suggest a significant potential for ecological interaction between hatchery and wild populations. I began this study with the intention of constructing a statistical model that would explain microhabitat preference of wild salmonids given the presence or absence of residual hatchery winter steelhead. To produce an unbiased model, ideally fish would behave as if there were no observer present (i.e., undisturbed). This is not always the case. Therefore, I addressed a second goal using underwater video to test the prediction that the presence of an in-water observer can elicit a change in fish movement. I analyzed underwater video recordings to document changes in four metrics that can be used to infer a change in fish behavior, which can ultimately result in collection of erroneous microhabitat use data. My four behavior metrics were upstream movement, downstream movement, total movement, and relative abundance of fish in the field-of-view. I detected significant differences in 9 of 10 replicates (ANOVA, P < 0.05) in at least one of the four behavior metrics. These results suggest that when attempting to document small-scale microhabitat preference by juvenile salmonids, an in-water observer may alter fish behavior thereby producing erroneous results. I suggest that researchers use caution in making inferences to entire populations when using results of models in which data were collected from only "undisturbed" fish by direct observation. Title: Habitat selection of hatchery and wild juvenile salmonids in Eagle Creek Basin, Oregon Author: Brignon, William R. To best manage Eagle Creek National Fish Hatchery and minimize any negative impacts that the current hatchery program may be having on Endangered Species Act-listed salmonids in the Eagle Creek Basin, I determined if wild fish are being displaced from preferred habitats by hatchery salmonids Oncorhynchus spp. This thesis had two goals. The first goal was to determine the possible effect of hatchery smolts on resident salmonids. I determined the density and distribution of wild juvenile steelhead O. mykiss and coho salmon O. kisutch in Eagle Creek and North Fork Eagle Creek, Oregon. My first objective was to compare summer rearing densities and distributions of wild salmonids in Eagle Creek, which receives a release of hatchery fish, and North Fork Eagle Creek, which does not receive a release of hatchery fish. Next, I determined if residual hatchery winter steelhead were present in Eagle Creek and/or North Fork Eagle Creek and if so whether or not they have an impact on mesohabitat selection, distribution, and density of wild fish in Eagle Creek basin. By conducting a comprehensive snorkel survey I identified significantly higher densities (P < 0.05) of juvenile coho salmon rearing in North Fork Eagle Creek as compared to upper and lower Eagle Creek. Age 0 winter steelhead occurred in significantly higher densities (P < 0.05) in upper Eagle Creek compared to lower Eagle Creek and North Fork Eagle Creek. Residual hatchery steelhead were located only in Eagle Creek and found rearing in the same 15 mesohabitat units that contained the estimated majority of wild fish populations. Residual hatchery steelhead comprised 0.9% of the winter steelhead population (1.1% of age 0 winter steelhead and 9.3% of age 1 winter steelhead), and 2.2% of the coho salmon population estimated to be rearing in Eagle Creek. From these data it is unclear if residual hatchery steelhead are affecting densities, distributions, and mesohabitat selection of wild salmonids in the basin. However, while I was unable to detect any direct impacts of residual hatchery fish on the wild population, these results do suggest a significant potential for ecological interaction between hatchery and wild populations. I began this study with the intention of constructing a statistical model that would explain microhabitat preference of wild salmonids given the presence or absence of residual hatchery winter steelhead. To produce an unbiased model, ideally fish would behave as if there were no observer present (i.e., undisturbed). This is not always the case. Therefore, I addressed a second goal using underwater video to test the prediction that the presence of an in-water observer can elicit a change in fish movement. I analyzed underwater video recordings to document changes in four metrics that can be used to infer a change in fish behavior, which can ultimately result in collection of erroneous microhabitat use data. My four behavior metrics were upstream movement, downstream movement, total movement, and relative abundance of fish in the field-of-view. I detected significant differences in 9 of 10 replicates (ANOVA, P < 0.05) in at least one of the four behavior metrics. These results suggest that when attempting to document small-scale microhabitat preference by juvenile salmonids, an in-water observer may alter fish behavior thereby producing erroneous results. I suggest that researchers use caution in making inferences to entire populations when using results of models in which data were collected from only "undisturbed" fish by direct observation. Close

• 29. [Article] An assessment of community-based adaptive watershed management in three Umpqua Basin Watersheds

  The dissertation introduces community-based adaptive watershed management (CAWM) as a holistic conservation framework. The CAWM framework integrates social and ecological suitability to achieve conservation ...

  Citation × Citation Citation Abstract Copy Title: An assessment of community-based adaptive watershed management in three Umpqua Basin Watersheds Author: Habron, Geoffrey Bryan The dissertation introduces community-based adaptive watershed management (CAWM) as a holistic conservation framework. The CAWM framework integrates social and ecological suitability to achieve conservation outcomes. The core theoretical concepts consist of adaptive management, adoption-diffusion, symbolic interactionism, community-based conservation, spatial analysis and watershed management. The CAWM framework is applied to the Calapooya Creek, Deer Creek and Myrtle Creek watersheds within the Umpqua River Basin in Southwestern Oregon. The goal of the research is to facilitate effective watershed restoration outcomes grounded in a solid understanding of social and ecological dynamics. Applying the CAWM framework provides the basis to determine the kinds of conservation practices to implement, the locations in which to implement them and the kinds of programs to stimulate their adoption. Therefore, the dissertation objectives are to: 1) identify agricultural landowner participation in watershed conservation projects; 2) assess the spatial distribution of watershed projects; 3) determine the characteristics of participating and non-participating landowners; and 4) determine the sociocultural, ecological and geographic constraints to adaptive watershed management. Data were collected during 1997-1998 using agricultural landowner interviews, a mail landowner survey and observations of the Umpqua Basin Watershed Council. Landowners' worldviews consist of independence, the importance of private property rights, aversion toward government interference and a belief in environmental resilience. Landowners implement upland conservation practices such as off-stream livestock water developments and rotational grazing more often than riparian fencing, riparian tree planting and installing fish screens on instream irrigation diversions. The key factors in adoption of conservation practices include the use of irrigation, shared management decisions with a spouse, a belief in scientific experimentation and discussion of conservation with others. Spatial analysis using geographic information systems indicate that a suite of conservation practices is needed to achieve a network of large, connected patches throughout the watersheds. Title: An assessment of community-based adaptive watershed management in three Umpqua Basin Watersheds Author: Habron, Geoffrey Bryan The dissertation introduces community-based adaptive watershed management (CAWM) as a holistic conservation framework. The CAWM framework integrates social and ecological suitability to achieve conservation outcomes. The core theoretical concepts consist of adaptive management, adoption-diffusion, symbolic interactionism, community-based conservation, spatial analysis and watershed management. The CAWM framework is applied to the Calapooya Creek, Deer Creek and Myrtle Creek watersheds within the Umpqua River Basin in Southwestern Oregon. The goal of the research is to facilitate effective watershed restoration outcomes grounded in a solid understanding of social and ecological dynamics. Applying the CAWM framework provides the basis to determine the kinds of conservation practices to implement, the locations in which to implement them and the kinds of programs to stimulate their adoption. Therefore, the dissertation objectives are to: 1) identify agricultural landowner participation in watershed conservation projects; 2) assess the spatial distribution of watershed projects; 3) determine the characteristics of participating and non-participating landowners; and 4) determine the sociocultural, ecological and geographic constraints to adaptive watershed management. Data were collected during 1997-1998 using agricultural landowner interviews, a mail landowner survey and observations of the Umpqua Basin Watershed Council. Landowners' worldviews consist of independence, the importance of private property rights, aversion toward government interference and a belief in environmental resilience. Landowners implement upland conservation practices such as off-stream livestock water developments and rotational grazing more often than riparian fencing, riparian tree planting and installing fish screens on instream irrigation diversions. The key factors in adoption of conservation practices include the use of irrigation, shared management decisions with a spouse, a belief in scientific experimentation and discussion of conservation with others. Spatial analysis using geographic information systems indicate that a suite of conservation practices is needed to achieve a network of large, connected patches throughout the watersheds. Close

• 30. [Article] Changes in storm hydrographs due to clear-cut logging of coastal watersheds

  The purpose of this study was to determine the effect of clearcut logging on stormflow by analysis of characteristic parameters of individual storm hydrographs. Parameters considered included height-of-rise, ...

  Citation × Citation Citation Abstract Copy Title: Changes in storm hydrographs due to clear-cut logging of coastal watersheds Author: Harper, Warren Charles The purpose of this study was to determine the effect of clearcut logging on stormflow by analysis of characteristic parameters of individual storm hydrographs. Parameters considered included height-of-rise, peak discharge, volume and time-to-peak. The hydrologic data were derived from experimental watersheds of the Alsea Study located in the Oregon Coast Range. Three clearcut watersheds were selected for study; Deer Creek IV (39 acres) was clearcut, and Needle Branch (175 acres) was clearcut and burned. Both watersheds were compared to Flynn Creek (502 acres), an untreated control, before and after treatment. Change in hydrologic paramaters was determined from differences between pre- and post-logging linear regressions. Statistical techniques were utilized to test for differences in slope or vertical position. Significant increases were found in peak discharge from both Needle Branch and Deer Creek IV following clearcut logging. Larger increases were noted during the fall period than during the winter period. Volume parameters of quick flow, delayed flow, and total flow were increased for Needle Branch. Volume of flow was not shown to increase from Deer Creek IV. This may have been due to the lack of usable storm events for analysis from this watershed. Time-to-peak was not altered in Needle Branch but was decreased for low flows and increased for high flows on Deer Creek IV. The height-of-rise parameter did not prove to be of value for detecting change in this study. Comparison of the burned watershed (Needle Branch) to the unburned watershed (Deer Creek IV) did not produce a noticeable difference in any of the parameters. The observed changes in stormflow were related to clearcut logging and the effect of vegetative removal on watershed response. Title: Changes in storm hydrographs due to clear-cut logging of coastal watersheds Author: Harper, Warren Charles The purpose of this study was to determine the effect of clearcut logging on stormflow by analysis of characteristic parameters of individual storm hydrographs. Parameters considered included height-of-rise, peak discharge, volume and time-to-peak. The hydrologic data were derived from experimental watersheds of the Alsea Study located in the Oregon Coast Range. Three clearcut watersheds were selected for study; Deer Creek IV (39 acres) was clearcut, and Needle Branch (175 acres) was clearcut and burned. Both watersheds were compared to Flynn Creek (502 acres), an untreated control, before and after treatment. Change in hydrologic paramaters was determined from differences between pre- and post-logging linear regressions. Statistical techniques were utilized to test for differences in slope or vertical position. Significant increases were found in peak discharge from both Needle Branch and Deer Creek IV following clearcut logging. Larger increases were noted during the fall period than during the winter period. Volume parameters of quick flow, delayed flow, and total flow were increased for Needle Branch. Volume of flow was not shown to increase from Deer Creek IV. This may have been due to the lack of usable storm events for analysis from this watershed. Time-to-peak was not altered in Needle Branch but was decreased for low flows and increased for high flows on Deer Creek IV. The height-of-rise parameter did not prove to be of value for detecting change in this study. Comparison of the burned watershed (Needle Branch) to the unburned watershed (Deer Creek IV) did not produce a noticeable difference in any of the parameters. The observed changes in stormflow were related to clearcut logging and the effect of vegetative removal on watershed response. Close