9th Annual Review Abstracts

The Development of an Old-Growth Floodplain Forest

Wood debris often defines a river's path and local flow conditions. Fluvially deposited wood forms the primary site of coniferous tree colonization on old growth floodplains in the coastal Pacific Northwest. Erosion, and subsequent channel migration, is the principal type of disturbance in these environments. The spatial pattern of vegetation over the valley forest is the result of erosion, deposition, and the distribution of wood debris colonization sites.

This study examined spatial relationships between wood debris and sediment deposition, channel migration, and floodplain and terrace forest development in the old growth Queets River valley, 45 km from the Pacific. A detailed sample grid was surveyed over 25 hectares of floodplain. Topography and vegetation characteristics were collected at each sample point. Individual wood jams were mapped throughout the study area. Historical aerial photos document channel changes since 1939. Arc Info (geographic information system) was used to conduct exploratory data analysis of spatial data.

Kevin Fetherston
College of Forest Resources
Box 352100
University of Washington
Seattle, WA 98195-2100
(206) 685-8658
feather@u.washington.edu

Historic and Current Distribution and Functions of Large Woody Debris in Puget Lowland Rivers

At present, big rivers in the Puget Sound Lowlands do not contain large amounts of functional woody debris. Current interest in restoring historically lost aquatic habitat requires information about historical amounts and functions of wood debris in large rivers. The perception that woody debris is not a primary influence on Puget Lowland rivers appears to reflect the cumulative effect of historic human actions rather than what the channels were like. Archival data, primarily from field reports of the Army Corps of Engineers, supplemented with field work in the unique Fort Lewis reach of the Nisqually River, which has been protected from development this century, indicates that woody debris was abundant in the late 19th century and had various geomorphic and biological functions. Raft jams up to a mile long and more than a century in age blocked several rivers. These rafts routed floodwaters and suspended sediment onto floodplains and deltas, diverted flow into floodplain sloughs and wetlands, and mediated the downstream flux of organic debris. At the rivers' mouths, miles-long drift jams plugged tidal sloughs and appear to have been important in delta and marsh evolution. Current conditions in the Nisqually River and records of a federal "snagging" program indicate that debris pieces were large and abundant as mid-channel snags and channel-margin debris jams. Conditions in the Nisqually River and inference from historic records suggest that in rivers throughout the Puget Lowland, wood debris jams created an anastomosing river pattern with numerous floodplain channels, and had a dominant influence on the quality and quantity of pools and other elements of aquatic habitat. Wood debris is not currently a dominant influence on typical Puget Lowland rivers, which have a history of wood debris clearing, floodplain channel elimination and forest conversion, and levee construction. Field inventory of wood debris in the Stillaguamish and Snohomish rivers in summer 1998 found that debris is dominated by numerous individual pieces of old, predominantly waterlogged cedar embedded in the bed at the channel margins. This remnant debris appears to have little geomorphic function. Younger debris tended to be on banks, and is mostly smaller deciduous pieces. It is likely that as relict debris continues to decay it will not be replenished because pieces currently falling into the river are smaller and more readily exported, and less durable. Restoring wood debris and debris accumulations is central to restoring the form and habitat of large Puget Lowland rivers. The floodplain forest history and age characteristics of wood debris in the Nisqually River suggests that a laterally mobile river with a mature floodplain forest can establish extensive debris accumulations, and the accompanying influences on channel morphology and aquatic habitat, within 50-100 years. Brian Collins
Dept. of Geological Sciences
University of Washington
Box 351310
Seattle, WA 98195-1310
(206) 616-9096
bcollins@u.washington.edu

Experimental Application of Engineered Log Jams:
North Fork Stillaguamish River, Washington

An experimental installation of five Engineered Log Jams (ELJs) completed in August 1998 culminated two years of extensive field and office preparation. Baseline data collection began summer 1996, when specified cross-sections were surveyed. During the summer of 1997, these cross-sections were re-surveyed and cross-channel pebble counts were conducted at each cross section. A survey of the reach found a pool frequency of 2.0 pools/km, with a maximum pool depth of 3.0m. Wood debris was measured, tagged, and mapped to track movement and to develop a wood budget for the reach. These data were used in conjunction with an historical analysis of the channel migration zone to develop preliminary designs to enhance habitat, protect a bridge pier, and prevent an imminent, undesirable avulsion. Two of the jams were designed to function individually to address specific objectives, whereas the other three incorporated a more experimental approach in which the jams are intended to function as a unit. To meet stability specifications over 500 trees with trunk diameters up to 1.3m and 5m rootwads were incorporated into the ELJs. Jams 1 and 2 are intended to provide bridge protection by means of flow deflection and by separating the main flow to form a forested island. Jams 3 to 5 should provide reach-scale bank protection to prevent the channel from re-occupying a floodplain side-channel. The design spacing and width of these jams was based on traditional design criteria for rock groins. Examination of flow separation envelopes and the relation between observed and predicted stream-bed changes will assess the appropriateness of using groin design parameters for log jam placement. We hypothesize that scour geometry will be consistent with patterns associated groin structures, but that the maximum depth and total volume will be greater. In addition, we expect that tail-out effects from flow separation in the lee of jams will be greater than found associated with rock groins. Numerical modeling of flow based on detailed surveys of the active channel and associated floodplain before and after construction will assess project impacts. Jam construction increased the pool frequency to 5.0 pools/km, including the two pre-existing pools that may or may not persist. We expect that after the first bed-mobilizing event two additional pools will form around jams 2 and 3. Perhaps the most fundamental hypothesis that we intend to test is that the ELJs will remain stable and develop holding pools within the active channel.

Tracy Drury
Dept. of Civil and Evironmental Engineering
University of Washington
Box 352700
Seattle, WA 98195-2700
tdrury@u.washington.edu

Suspected Asian Air Pollution Influences Stream Chemistry in an Old-Growth Ecosystem in the Hoh River Valley

In the eastern United States nitric acid deposition has led to increases in nitrogen losses via streams, concerns about water quality, and decreases in forest health. Nitrogen deposition has been generally low in the western United States, although increases in nitrogen deposition have been forecast due to the steady increase in use of nitrogen fertilizers in Asia. Pollution outflow from Asia across the North Pacific has been observed and some reaches the west coast of North America. Tropospheric air masses from Asia are rich in nitrogen relative to sulfur. Will increased nitrogen inputs to old-growth forests of the Pacific Northwest cause nitrate losses and stream acidification? Nitrate concentrations and pH in precipitation and the stream have been monitored since 1984 in the 58 ha West Twin Creek watershed in the Hoh River Valley in Olympic National Park. Old-growth forest occurs in the watershed. We analyzed the precipitation and stream chemistry data from 1984 to 1993 and concluded that there was no evidence of transport of NO₃-N across the Pacific Ocean from Asia. However, from autumn 1993 to mid 1996 there was a dramatic increase in NO₃-N concentrations in precipitation and then a return to near pre-1993 concentrations. Annual NO₃-N inputs went from <1 kg ha-1 yr-1 to 7.5 kg ha-1 yr-1. Bulk precipitation pH fell from 5.3 to as low as 4.0 in this period due to nitrate and sulfate inputs. At the end of 1997 precipitation pH still had not returned to the average of 5.3. From 1993 to 1996 stream NO₃-N concentrations also increased. Stream pH decreased from 7.3 to as low as 4.5 and then increased in 1997. It appears that the increased NO₃-N concentrations and lowered pH in precipitation we observed are due to across Pacific transport of NO₃-N from Asia. Because this relatively pristine old-growth temperate rainforest ecosystem was near nitrogen saturation, stream NO₃-N concentrations quickly increased, and the stream was acidified. This change in stream chemistry has important implications with respect to forest health, stream biology, and salmon production.

Bob Edmonds
College of Forest Resources
University of Washington
Box 352100
Seattle, WA 98195-2100
(206) 685-0953
FAX (206) 685-3091
bobe@u.washington.edu

Stream Chemistry in Harvested and Old-Growth
Forests in the Hoh River Valley

A preliminary study comparing stream chemistry was conducted in two DNR harvested watersheds, Rock and Tower Creek and an uncut old-growth watershed, West Twin Creek (WTC) all located in the Hoh River Valley on the Olympic Peninsula, Washington. Stream chemistry in Rock and Tower Creek were first monitored in 1975 - 1977, Larson (1979), before a section of each watershed was harvested in 1981 and 1985/1987 respectively. Although Douglas-fir was replanted red alder, a nitrogen fixer, dominates the stream side near the weirs. We collected grab stream water samples monthly, from May of 1996 to May of 1998, and analyzed them for pH, conductivity, nutrients, and major cations and anions. Results show that concentration of most cations and anions were slightly higher in WTC versus both Rock and Tower Creeks, the exceptions being chloride and potassium. The small differences are likely due to the larger size of the harvested watersheds. Nitrate concentrations did not differ with the exception of a summer peak occurring in 1996 that spanned 2 months in the harvested creeks. The nitrate peak does coincide with an increase in rain nitrate concentration, suggesting that the harvest watersheds are as "leaky" as the old-growth watershed. However, it is unknown if the riparian areas of red alder are also contributing to the nitrogen leaching into the stream.

This preliminary work indicates that the stream chemistry of these partially harvested watersheds is not different from the old-growth watershed after 10-15 years. Any possible effects of harvesting on soil chemistry may have recovered over time or the proportion of the area that was cut is not large enough to influence the stream chemistry. Another comparison can be made with the stream chemistry of the DNR watersheds before they were logged. Rainfall amount in the water year 1975-1976 was similar to 1996-1997, 536 cm and 493 cm respectively. We compared the average concentration from before and after harvest over these time periods. Although many chemical constituents were slightly higher in the post harvest year this small increase may again be due to differences in discharge. A younger forest, planted Douglas-fir, may have more water demands and evapotranspiration resulting in less discharge than the pre-harvest watersheds.

Georgia Murray
College of Forest Resources
University of Washington
Box 352100
Seattle, WA 98195-2100
gmurray@u.washington.edu

Flood and Drought:
Controls on Nitrate Leaching from a Floodplain Forest

Successional processes following disturbance may be an inportant influence on nutrient cycling in streams. In the Pacific Northwest, nitrogen (N) fixation associated with red alder leads to rapid N accumulation in recently deposited riparian soils. In order to gauge the potential for N exchanges between riparian soils and the aquatic ecosystem, seasonal and successional variation in retention and loss of soil N was studied on the Queets River floodplain. Fall peaks in surface and ground/hyporheic water nitrate were observed at all sites, and resulted primarily from increased transport during autumn storms. Readily leachable nitrate accumulated in soil throughout the summer, with the greatest increases occurring during drought-like conditions in late summer. Although leaf abscission and other seasonal vegetational changes influence N cycling, they appear to be of less direct importance to fall leaching losses.

Total soil N increased rapidly during the first 20-30 years that alder was the dominant canopy species. Older alder patches (40-70 years) had lower N accretion rates but experienced much greater N leaching. This suggests continued high rates of N-fixation in older stands, combined with a limited capacity for retention of fixed N, and contrasts with the results of other studies that have found reduced N-fixation in older alder stands.

Scott Bechtold
College of Forest Resources
University of Washington
Box 352100
Seattle, WA 98195-2100
(206) 616-9421
sbech@u.washington.edu

Modeling Basin-Wide Trends in Land Use and Water Quality:
A GIS-Based Landscape Analysis Tool

Human land uses are the major source of disturbance in most catchments. Effective ecosystem restoration requires an understanding of how past and current land use affects ecosystem processes throughout a river basin. Restoration planning should include informed estimates of how future basin development will alter those patterns. Describing and modeling those relationships requires techniques that can integrate complex combinations of individual process impacts over entire basins or ecoregions. Application of process-based hydrologic/water quality models over large time and space scales is expensive and problematic. Empirical non-point source models that relate basin-wide landscape trends to water quality offer promise, but all require assumptions about the scale and grain of the dominant interactions . The most fundamental problem is determining the valid upstream area within which aggregated landscape properties exert a measurable influence over the variable of interest within the river. Past basin- scale studies suggest that landscape-water quality relationships change systematically with position along the drainage. We are developing a simple GIS-based landscape-water quality modeling approach that can be used to empirically test which portions of the upstream landscape best predict measured water quality trends. As well as offering a more systematic approach to model development, this approach may be used to explore the potential effectiveness of alternative stream buffer sizes for stream restoration and management.

Rick Edwards
School of Fisheries and
College of Forest Resources
University of Washington
Box 352100
Seattle, WA 98195-2100
(206) 543-3507
FAX: (206) 543-3254
ricke@fish.washington.edu

Modeling Basin-Wide Trends in Land Use and Water Quality: Relating Water Quality to Landscape Trends

We are developing an empirical model designed to relate basin-wide land use patterns to stream water quality trends. Using watershed characterizations generated by the landscape analysis model and water quality data sets, we are combining regression analysis and scaled longitudinal plots to determine which water quality variables are sensitive to major changes in land use. Including the longitudinal dimension is important in visualizing relationships between water quality and land use, such as the correlation between turbidity and urban areas or temperature and agricultural areas. Our analysis has revealed unexpected relationships among agriculture, urban areas and several water quality parameters. The next step in model development will examine the importance of spatial relationships, and examine how the size of the influential area of adjacent land use changes in relation to position within the basin. Final development of the model will yield a management tool to explore the effects of alternative land use patterns on future water quality patterns.

Nancy Gove
Quantitative Ecology and Resource Management
University of Washington
Box 3517200
Seattle, WA 98195-1720
nancy@cqs.washington.edu

Incorporating Judgment Into Sampling Approaches for Streams

Data collection from rivers and streams is often time consuming and labor intensive. The large amount of natural variability makes intensive sampling necessary, and difficult. Researchers are sometimes frustrated by the statistical necessity of random samples. However, there are several sampling methods that incorporate researcher judgment or extra information into choosing samples. One class of sampling methods is called "double sampling." Double sampling is used when what you are interested in is time consuming or expensive to measure, and there is also another way to approximate the same information using a "quick and dirty" method. Double sampling uses this extra information or researcher judgment to get a better estimate than you could without it. There are several types of sampling methods which use extra information, and the choice depends on how much you know about your data prior to sampling. One method, ranked set sampling, will be described and compared with other more well known sampling methods such as ratio estimation (Hankin and Reeves 1988). A table outlining several sampling methods, along with the prior information needed, will summarize how judgment or extra information can be included in several sampling methodologies.

Nicolle Mode
Quantitative Ecology and Resource Management
University of Washington
Box 351720
Seattle, WA 98195-1720
(206) 616-9440
nicolle@cqs.washington.edu

Use of Evaluation in Stream Restoration and Fisheries Enhancement Projects in Washington State

This study is designed to examine a perceived lack of evaluation of stream restoration and fisheries enhancement projects in Washington State. While the goal of many of these projects is to improve or restore fish habitat and subsequently increase fish populations, it is not always know to what extent projects are evaluated over time to determine if these goals are being met. This problem is important for natural resource management, as stream restoration and fisheries enhancement projects have received increased attention and financial support in recent years.

This study will investigate the degree to which restoration and enhancement projects in Washington State are being evaluated and/or monitored. Further, for those projects where evaluation is occurring, the types of evaluation used will be described . In addition, this research will explore the relationship between the use of evaluation methods and characteristics of the project, such as the type of organization conducting the activity, funding sources, and region of operation. The study will also identify the barriers project managers encounter in their efforts to measure improvements in stream health.

Project managers of stream restoration and fisheries enhancement projects were the target population for the survey. The subject pool was drawn from hydraulic permits issued by the Washington State Department of Fish and Wildlife. Based on the survey results, a small number of projects will be selected for case studies. The information gained from this study may help project managers and those funding projects to better understand the current strengths and limitations of evaluation of restoration or enhancement projects, and allow them to adjust their policies accordingly.

Jeff Bash
College of Forest Resources
University of Washington
Box 352100
Seattle, WA 98195-2100
(206) 616-2874
jbash@u.washington.edu

Participant Influence on Design of Habitat
Enhancement Projects

An empirical study was conducted across Washington State to explore the social dynamics of designers and other project participants involved in fish habitat improvement projects. Over sixty habitat projects receiving HPA permits during the 1997 year were included in the study. Data ware collected from permit files, structured phone interviews with key participants, site visits and a follow-up mailed survey. In all over 200 persons were identified as having a role in the projects.

Design features of projects varied widely. Choice of design elements appeared to be cultural as well as based on cost and functionality. We found compelling evidence of design being a social process that readily accommodated stakeholder objectives and constraints. Traditional engineering decision making methods were not used in spite of the highly technical nature of many projects.

Jim Dooley
College of Forest Resources
University of Washington
Box 352100
Seattle, WA 98195-2100
(206) 685-2091
jdooley@u.washington.edu

The Influence of Sediment Supply and Large Woody Debris
on Pool Characteristics and Habitat Diversity

In free-running Western Washington rivers, channel morphologies are largely shaped by peak flow events. Sediment aggradation and scour shape a continuum of instream habitat which provide a template for the biotic features of the river. In regulated waters, habitat heterogeneity is often reduced in response to more homogeneous flow regimes. Furthermore, the regulation of rivers often alters the temperature regime downstream, thereby affecting the growth rates and life histories of the biota downstream. As a result, the abundance and composition of food available to fish as drift may also be modified by regulation. The Tolt River in Western Washington offers a unique opportunity to quantify the effects of river regulation in the Pacific Northwest. While the North Fork of the Tolt is free-running, the South Fork has been dammed to form a water storage reservoir for Seattle Public Utilities. Three study sites have been identified on each fork to provide within and between fork comparisons of (i) the density and composition of invertebrate drift, and (ii) the growth rates, condition analysis, population size estimates, and stomach contents of resident rainbow trout and presmolt steelhead, Oncorhynchus mykiss. This study has direct implications in the management and protection of Western Washington's wild resident rainbow trout and presmolt steelhead. As the number of dammed rivers in the United States increases, a growing percentage of the stream habitat available for salmonids exhibits altered water temperature and discharge regimes. It will be in the best interest of fishery managers to be able to anticipate the effects of river regulation on the abundance and composition of invertebrate drift, and salmonid growth rate.

Jamie Glasgow
School of Fisheries
University of Washington
Box 357980
Seattle, WA 98195-7980
(206) 543-7443
glasgow@fish.washington.edu

Response of Juvenile Stream Fishes to Instream Restoration
in Western Washington and Oregon

Thirty streams in western Washington and Oregon with paired restored (treatment) and natural (control) reaches are being sampled to determine the response of fishes to artificial large woody debris (LWD) placement. Initial results indicate that overall, densities of juvenile coho salmon (Oncorhynchus kisutch), larval lamprey (Lampetra sp.), and age 0+ reticulate sculpin (Cottus perplexus) were significantly higher in treatment than control reaches during summer months (p< 0.05). Conversely, no significant differences in densities between treatment and control reaches were found for young of year trout (age 0+), cutthroat trout (Oncorhynchus clarki), steelhead (Oncorhynchus mykiss), reticulate sculpin (age 1+), either age class of torrent sculpin (Cottus rhotheus), or Pacific giant salamanders (Dicamptodon ensatus). Preliminary analysis of winter data, which are currently being collected, indicates significantly higher densities of juvenile coho salmon in treated stream reaches, but no significant differences for other species. Regression analysis indicates that differences in fish response to restoration among streams are positively correlated to changes in physical variables such as LWD loading and pool frequency. Additional data collection and analysis is currently underway to further.

Phil Roni
School of Fisheries
University of Washington
Box 357980
Seattle, WA 98195-7980
(206) 860-3307
phil.roni@noaa.gov

Developing a Biological Framework for the Evaluation of Urban Stream Restoration Projects

In restoration projects driven by a desire to boost dwindling populations of salmonids, taking direct measurements of biological health is imperative. In urban streams, directly monitoring fish is often problematic for a variety of reasons. Towards that end, a regionally based index of biotic integrity (B-IBI) has been developed for the Puget Sound Lowlands using benthic macroinvertebrates. This index is comprised of ten individual metrics that range from taxa richness and trophic structure to pollution tolerances. The ability of the B-IBI monitoring approach to distinguish sites along a gradient of human influence has been demonstrated by past studies. The utility of this measure in evaluating restoration projects is still untested. Efforts thus far have been limited by both the methods used to characterize human influence and by our understanding of how individual metrics of the B-IBI respond differentially to degradation. In this study, we are investigating the response of B-IBI metrics to changes in physical and hydrologic features of the stream channel. These features of physical stream habitat will in turn be examined in the context of land cover changes, at multiple scales within each study basin. Our objective in assessing these relationships is to increase the descriptive and diagnostic properties of the B-IBI for use in evaluating urban stream restoration projects.

Sarah Morley
School of Fisheries
University of Washington
Box 357980 Seattle, WA 98195-7980
(206) 616-3660
FAX (206) 543-2025 smorley@fish.washington.edu

Re-equilibration of Stream Channels in Urban Watersheds

With the onset of urbanization, increased stream flows and an altered sediment budget disturb a stream's geomorphic equilibrium and most commonly result in enlarged, unstable channels. However, the channel's ability to reestablish an equilibrium form over time is not well understood. This research seeks to evaluate the long-term response of stream channels to urbanization to determine whether urban channels restabilize once watershed development ceases.

This study encompasses several streams in 10-30 km² catchments in the Puget Sound Lowlands of western Washington. The extent of urbanization ranges from "transitional" basins, where development is ongoing or only recently completed, to "post-development" basins, where land use has been nearly constant for at least a decade. Field surveys and observations were made during the summer and fall of 1998 to assess the current stability of each channel. Extent of urban development was evaluated from sequential aerial photos.

Preliminary results suggest that constant land use and channel stability are at least grossly well correlated in many urban basins. Kelsey Creek (drainage area 15 km²) drains a fully developed basin, where land use has been relatively constant for the last 15 years. Field observations indicate a stable channel, suggesting that the channel has completely adjusted to accommodate the increased storm flows caused by urbanization. Juanita Creek (drainage area 17.5 km²) drains a mostly developed basin that has experienced continuous gradual development since the mid-1950's. Several reaches exhibit characteristics of slight to moderate instability, and there is evidence that the channel is still widening. Since the basins are in close proximity and have similar physical characteristics, a temporal link between channel stability and stable land use is implied. The degree to which these results can be generalized, considering the variable geomorphic context of different locations within a channel network, is being explored with additional study of similar streams in the region.

Patty Henshaw
Center for Urban Water Resources Management Dept. of Civil and Environmental Engineering
University of Washington
Box 352700
Seattle, WA 98195-2700
(206) 543-6272
phenshaw@u.washington.edu

Effectiveness of Large Woody Debris in Urban Stream Rehabilitation Projects

Large amounts of money are spent on in-channel projects in urban or urbanizing watersheds without knowing their effectiveness. It is unclear if rehabilitation measures can reverse even local expressions of the consequences of watershed disturbance. In-channel rehabilitation projects often utilize anchored wood and, increasingly, large woody debris (LWD) to establish geomorphic and habitat features associated with LWD in undisturbed streams. Altered hydrological regimes and high sediment loads in urbanized basins, however, may preclude the desired functions of LWD. This study is evaluating the geomorphic response to in-channel wood installed to improve local habitat conditions, erosion and sedimentation patterns, and flooding concerns on 5 streams in the lowland Puget Sound area. These streams represent a range of sizes, draining watersheds from 2.3 to 65 square kilometers. The projects have been in place from 3 to 18 years and employ a range of techniques, from log deflectors to unanchored wood, intended to mimic natural LWD. These projects are being evaluated along a continuum of watershed and riparian conditions from "ideal" (forested with high LWD loading) to "degraded" (urban with no LWD loading). In-stream structures, if effective, will cause reach-level conditions to increasingly look like those typical of forested basins with high LWD loading. Stream characteristics being evaluated in the project reaches include LWD frequency, pool spacing, width, and channel storage elements. These physical adjustments of the channel are assumed to be a prerequisite for (although not a guarantee of) biotic improvements in response to the rehabilitation efforts. At several of the sites selected for this study, data on the benthic macroinvertebrate populations have been collected by Sarah Morley of the UW School of Fisheries. When these data become available, they will be used to assess whether biotic integrity appears to adjust in consort with physical channel characteristics at the scale of a project reach.

Marit Larson
Center for Urban Water Resources Management
Dept. of Civil and Environmental Engineering
University of Washington
Box 352700
Seattle, WA 98195-2700
maritl@u.washington.edu

Salmon Recovery Plans for the Columbia River Basin:
Does a River Run Through Them?

Within the last several years a number of important documents related to salmon recovery in the Columbia River Basin have been produced, each purported to be based on sound science and each containing various conclusions and recommendations for changes in management practices. The Independent Scientific Advisory Board (ISAB) to the Northwest Power Planning and the National Marine Fisheries Service felt it would be useful to both policy makers and managers to identify the major points of agreement and disagreement among these reports and have therefore initiated a comparison. The project began in early 1997 and the original intent was to compare the findings of the Independent Scientific Group's report "Return to the River", the National Research Council's report "Upstream", and the draft report of the interagency task force on management of federal lands in the interior Columbia River Basin, which was subsequently issued as a report of the US Forest Service and Bureau of Land Management (a.k.a., ICBEMP) in mid-1997. The comparison was subsequently expanded to include the National Marine Fisheries Service 1995 "Proposed Recovery Plan for Snake River Salmon" and the Columbia River Inter-Tribal Fish Commission's salmon recovery plan "Wy-Kan-Ush-Mi Wa-Kish-Wit, Spirit of the Salmon", as these two documents were also being used to guide a number of important management decisions in the basin. We realized that the specific focus of each report was somewhat different, depending upon particular management issues with which each was primarily concerned. Nevertheless, we identified eight topics that were addressed in many of the documents: (1) conceptual foundation, or the basis for implementing strategies and tasks, (2) natural variation, (3) habitat, (4) artificial propagation, (5) hydroelectric operations, (6) salmon harvest, (7) institutions, and (8) monitoring and evaluation. No single report dealt in detail with all these topics and some topics were clearly beyond the mandate of the particular sponsoring organization or agency. But there was enough information to make comparison worthwhile. We generally found the reports agreed on issues that did not involve extensive technological fixes (e.g., habitat protection) but diverged widely on issues where technology was heavily utilized (e.g., artificial propagation, operation of the hydroelectric system). If you had to administer a multi-million dollar budget for salmon recovery in the Columbia Basin, would you give priority to issues over which there is scientific consensus or spend most of the money on projects over which there is little agreement?

Peter Bisson
USFS Forestry Sciences Lab
3625 93rd AVE SW
Olympia, WA 98512
(360) 753-7671
(360) 956-2346
bissonp@olywa.net

A Century-Long Experiment in Population Evolution:
North American Salmon in New Zealand Rivers

Transplants provide semi-natural experiments for empirical study of population establishment and divergence, topics of concern in the conservation of salmon. Around 1904, chinook salmon (Oncorhynchus tshawytscha) were transplanted from a tributary of the Sacramento River, CA, to New Zealand (NZ) where the rivers they occupy are much shorter, more flood prone and without estuaries. Though the NZ rivers are more similar to each other in many ways than they are to the Sacramento and its tributaries, previous comparisons based on archival adult life history data indicated phenotypic divergence among populations within NZ. To determine the basis of observed phenotypic divergence we reared families from two NZ populations to maturity under shared conditions and released juveniles from both to rear in the wild. We have examined a range of juvenile and adult traits including, early development rates, fry growth, salinity tolerance, maturation and return timing, size at age, reproductive traits, and survival. Recently, we have also incorporated another population into our comparison program. Our results to date indicate that a combination of genetic and environmentally based differences have arisen, over approximately 30 generations, between populations from a common introduction source. Some patterns in our results suggest that some types of traits may be more prone to genetic divergence on this time scale. Knowledge of evolutionary rates on relatively short time scales (e.g. over a century) has implications for how we evaluate divergence and plan population recovery programs, as well as for our perceptions of the tempo and mode of evolution occurring in populations during our own lifetimes.

Mike Kinnison
School of Fisheries
University of Washington
Box 357980
Seattle, WA 98195-7980
(206) 543-7745
mikek@fish.washington.edu

How Juvenile Salmonids Spend Their Summers:
Fish Movement Patterns in Coastal Streams

The National Marine Fisheries Service (NMFS) is currently studying the effectiveness of stream restoration projects at increasing the growth and survival of juvenile salmonids. In an effort to understand the potential fish response to a restoration project, NMFS has funded my Master's thesis project, which is the study of the summer movement patterns of stream-dwelling juvenile salmonids. The basic study design is to determine the movement patterns of individually marked juvenile coho salmon and steelhead, and cutthroat trout using periodic snorkel surveys and recapture. The study began in 1997 using a low-gradient (0.8%) stream, and was repeated in 1998 using the same low-gradient stream, and two additional streams, one with a 2% gradient and the other with a 6.7% gradient.

In the low gradient stream in 1997, 44% of the fish for which data was recovered had moved from their tagging location. Of these, 60% had moved upstream. There was no significant difference in the initial lengths (length at tagging) of fish that moved and those that did not move, or in the initial lengths of upstream and downstream movers. In 1998, the number of movement events was used as comparison rather than the final location of the fish. In the low-gradient stream, 28% of the fish had moved: 90% of the fish moved upstream (made at least one upstream movement), and 34% moved downstream (some moved both directions). In the 2% gradient stream, 54% of the fish moved: 76% moved upstream, 52% moved downstream. In the high-gradient stream 60% of the fish moved: 52% moved upstream, 64% downstream. In all streams, there were no significant differences in the initial lengths of movers and non-movers, or upstream and downstream movers. In the high-gradient stream only, there was a significant difference in the distance moved upstream vs. downstream. The mean upstream distance moved was 2.6 habitat units, the mean downstream distance was 9.8 habitat units. The analysis of these data continues.

Tom Kahler
School of Fisheries
University of Washington
Box 357980
Seattle, WA 98195-7980
(206) 616-9419
tkahler@fish.washington.edu

Comparison of Stream Source Water Temperatures
Against Various Regulatory Threshholds

A list was compiled of the various methods used in studies over the years for comparing stream temperatures and of different stream peak temperature regulatory variables and criteria. Summer temperature data collected from small stream sources on the western Olympic Peninsula were summarized using the compiled methods and evaluated against the regulatory criteria. Most of the source water temperatures from both managed and unmanaged sites exceeded established and proposed regulations. Since streams generally increase in temperature as they flow downstream, the fact that the source temperatures don't meet regulations means the downstream temperatures aren't likely to, no matter what the riparian management status is. This suggests that another look at peak stream temperature regulatory methods and criteria is warranted.

Jenelle Black
College of Forest Resources
University of Washington
P.O. Box 58
Hyak, WA 98068
blackjs@u.washington.edu blackjs@u.washington.edu

Wood Distribution in Unmanaged Streams:
A Diagnostic Approach Based on Geomorphic Variation

Large woody debris (LWD) in Pacific Northwest streams is recognized as an important feature linked to channel processes that benefit salmonids. Stream channel assessments often associate the size, distribution, and abundance of woody debris to salmon habitat quality. Target wood values for quantity, size, and distribution have been developed for assisting resource managers to evaluate and manage streams; however, they do not account for geomorphic variability and are subsequently inaccurate for some streams. Because resource managers frequently rely upon standardized wood targets for multiple channel types when making decisions, a great need exists to refine current methods to more accurately account for natural variation among these channel types. This study will attempt to refine the current wood diagnostics or target criteria, and establish a basis for defining key parameters of wood quantity and quality in a stream based on the historical range of conditions given the natural disturbance regime. To accomplish this, surveys will be conducted to collect data on wood quantity, size, and distribution in unmanaged watersheds over a wide range of channel types. Second, methods such as regression analysis will determine distinctions in wood abundance, distribution, and size among channel types based on variations in geomorphic stream characteristics (width, gradient, confinement, geology). Finally, a channel classification system incorporating patterns of variability in the data will be developed (or fit to an existing method) that identifies appropriate wood loading targets applicable to resource management. These target conditions can help guide resource management for stream assessment, restoration, and enhancement projects that benefit salmonids.

Martin Fox
College of Forest Resources
University of Washington
Box 352100
Seattle, WA 98195-2100
mjfox@u.washington.edu

Regional, Synchronous Field Determination of Summertime Stream Temperatures in Western Washington:
600 Sites in 120 Minutes

The Center for Urban Water Resources Management (CUWRM), with cooperation from the Center for Streamside Studies and local stormwater agencies, tribes, and citizen groups, coordinated a regional, one-day intensive stream-temperature monitoring survey on August 19, 1998. Our intention was to characterize the range, distribution, and determinants of summertime high temperatures in fish-bearing (and tributary to fish-bearing) lowland stream systems in the Puget Sound lowlands. Cold-water fisheries can be strongly affected by elevated summertime stream temperatures, but the causes for and the magnitude of these conditions are relatively well understood only in the abstract. Their quantification in any given watershed is confounded by the vagaries of groundwater and surface-water inflows and the complex interplay of stream orientation and sun angle, canopy cover, and air temperature. Individual temperature measurements can give insight into the specific conditions for a particular stream, but they do not provide the context to evaluate unusual natural or human-induced temperature conditions at any given site.

To provide this context, over 100 individuals, representing approximately 20 different agencies and community groups, collected over 600 temperature measurements across the south-central Puget Lowland in the two-hour period from 3:00 to 5:00 PM on August 19th. Sites were arrayed to provide coverage of both scattered individual sites and whole stream systems on a watershed-wide basis, with drainage areas ranging from 100 km2 on down to the limits of perennial flow. Reflecting our interest in quantifying human influences, we targeted watersheds with primarily urban and suburban land uses but included some rural and forested basins as controls. About a dozen sites with continuous recording temperature gauges already installed were also covered to provide a temporal context for these "snapshot" data. Our intention is to provide a systematic, regional data set available to all scientists, planners, and managers to improve our understanding of the magnitude of high-temperature problems in developing parts of the region, and to guide strategies for their correction.

Although our sample date missed the hottest interval of 1998, the maximum air temperature on August 19 was exactly the average for the month of August (24 0C), and our sample period (3-5 PM) was within 1o C of the maximum water temperature of that day. Thus, the results we report are representative of "normal" but not "extreme" conditions.

The full data set is posted on the CUWRM web site and is available for downloading as an Excel spreadsheet. We invite readers to explore the information contained in this data set, and to share with us any fruits of your analyses.

Derek Booth
Center for Urban Water Resources Management
University of Washington
Box 352700
Seattle, WA 98195-2700
(206) 543-7923
dbooth@u.washington.edu

Biophysical Characteristics and Summer Use by Juvenile Salmonids of Off-Channel Habitats of the
Queets River Olympic Peninsula

In the lower reaches of the Queets River, the floodplain is dissected by a network of aquatic habitats formed by flooding and migration of the active channel. Evidence suggests that such off-channel habitats are important summer rearing areas for juvenile anadromous salmonids (Oncorhynchus spp.). The objectives of this study are to describe the physical character of off-channel habitats of the Queets River during the summer low-flow period, to organize the observed variation into a classification scheme distinguishing habitat types, and to assess differences in habitat quality among types by measuring juvenile salmonid distribution, standing crop, and size characteristics. Study sites on the Queets River were sampled during the summer in 1997 (n=11) and 1998 (n=20) using a combination of habitat characterization and electrofishing methods. Results indicate clear patterns in habitat character among types. Sites can be organized along a gradient of distance from the mainstem, from exposed side channels and scour pools on cobble bars adjacent to the active channel, to back channels and percolation channels flowing through alder-dominated terraces, to tributaries and spring ponds on the terraces. With increasing distance from the mainstem, there were attendant decreases in width and depth, size of LWD jams, substrate size, temperature, electrical conductivity, and increases in substrate embedded-ness, overhanging vegetation, CWD, canopy coverage, bank undercutting and other forms of instream cover. Patterns in distribution and densities of juvenile salmonids among off-channel habitat types are not as clear, but appear to reflect differences at the habitat unit (e.g. pool, riffle) rather than at the whole site (e.g. back channel) scale. Low flows during summer 1998 also compromised areal extent and accessibility of most off-channel habitats. Ultimately, we hope that lessons learned on the Queets River can be applied in more heavily impacted systems.

Treva Coe
School of Fisheries
University of Washington
Box 357980
Seattle, WA 98195-7980
(206) 616-9421
tcoe@fish.washington.edu

Design of In-Stream ELWd^TM Structure
Using Appreciative Design Method

Over the past 100 years we have witnessed dramatic declines in salmonid populations in the Pacific Northwest. Although hatchery influences, dams, and overfishing have also played significant roles, freshwater habitat loss and degradation is acknowledged to have contributed to the decline of virtually every species of Pacific salmon in western North America (National Research Council 1996; Nehlsen, et al. 1991). For seventy years landowners, foresters, biologists, civil engineers and others removed large woody materials such as logs, rootwads and stumps from streams and rivers of the western United States and Canada. Their reasons included recovery of salable wood, efforts to improve fish passage, and attempts to increase river channel conveyance. As recently as two decades ago, volunteer crews spent every summer pulling wood out of streams across the Pacific Northwest. By the early 1980's, scientists began to recognize the critical roles that wood play in the life cycle of salmon and trout, as well as the benefits of wood for storing sediment and retarding flood flows. Removal of wood greatly decreased the carrying capacity of streams for juvenile salmonids, contributing to the decline of numerous salmon runs. Today, wood is being restored to streams of almost every watershed across western North America and riparian corridors are being revegetated to provide a continuing flux of wood in the future.

This paper focuses on the design and development of an engineered alternative to native large woody debris for use in the restoration of streams of the Pacific Northwest. The Appreciative Design process (Dooley and Fridley 1996) was followed to create a LWD solution that may be preferred for many fisheries enhancement efforts. The Appreciative Design process is a significant extension of the hierarchical axiomatic design methodology of Suh (1990; 1995a) and includes many features of the Soft Systems Methodology developed by Checkland (1990).

Jim Dooley
Silverbrook Limited
1911 SW Campus Dr. #545
Federal Way, WA 98023-6441
jdooley@seanet.com

Effect of Marine-Derived Nutrients on Insect Production in Salmon Spawning Streams

As salmon populations and the ecosystems they inhabit deteriorate, it becomes increasingly vital to describe the trophic linkages that support ecological health. It has been established that marine-derived nutrients (MDN) released from decomposing, salmon carcasses are utilized by stream and riparian organisms. To quantify the importance of aquatic insects in their role of transferring MDN from adult to juvenile salmon, I propose to study the response of insect production to salmon carcass decomposition. Productivity estimates, which describe changes in biomass over time, provide a measure of the total energy available to higher consumers. In addition, I intend to evaluate the relative importance of the major pathways of MDN through stream insects by monitoring changes in productivity in each trophic category.

Jon Honea
College of Forest Resources
University of Washington
Box 352100
Seattle, WA 98195-2100
(206) 543-5767
jhonea@u.washington.edu

Inferring Redd Siting Preferences from Velocity,
Depth, and Substrate

Depth, velocity, and substrate size observations at spawning sites (Kennedy Creek in Puget Sound, western Washington) are analyzed to infer chum salmon spawning site preferences. A distinction is drawn between where chum prefer to spawn and where they are observed to spawn, the latter being a function of both site preference and site availability. The underlying preference for depth, velocity, and substrate size is assumed to drop to zero at depth/velocity/pebble sizes of zero and infinity, and peak somewhere between. Bayesian inference on the observed site properties is used to constrain the location and sharpness of this peak. The inferred preferences suggest that Kennedy Creek chum prefer slower currents and larger substrates, but similar depths.

Finn Krogstad
College of Forest Resources
University of Washington
Box 352100
Seattle, WA 98195-2100
(206) 685-2091
fkrogsta@u.washington.edu

Influence of Conversion of Alder Riparian Stands to Conifers on Soil Properties along Brown's Creek in the Snokomish River Basin: Preliminary Results

Riparian vegetation in western Washington is commonly dominated by red alder, an aggressive, fast-growing, but short-lived hardwood that thrives on moist, disturbed sites. Because it is an N-fixing species red alder improves disturbed sites by adding nitrogen and organic matter to the soil. Nitrogen additions to ecosystems are not always beneficial, however. In particular, excess nitrogen contributions to streams can have a fertilization effect that encourages algal blooms which decrease overall habitat quality for fish and invertebrates. This has important implications for salmon which are currently declining. Managers have become concerned about the presence of red alder in riparian zones not only because of water quality issues, but because alder stems do contribute long-lasting large woody debris (LWD) to streams. LWD is an important structural component in salmon streams. Not only are they small, but alder logs decompose more rapidly than conifer logs. Thus there is a perceived need to convert alder stands to conifer stands in riparian zones in western Washington. The U.S. Forest Service has begun to kill red alders and plant western red cedar seedlings along Brown's Creek, a tributary of the Skokomish River, in the Olympic National Forest. We know very little about the soils in riparian zones. The purpose of this preliminary study was to describe the variation in soil properties and vegetation along 40 m transects away from the creek in treated (alder girdled two-years ago and cedar seedlings planted) and untreated areas. Soil samples (0 - 10 cm) were collected 0 - 2, 15 - 20, 30 - 35 and 40 m from the stream bank on November 5, 1998. Soil texture, pH, percent moisture, soil organic matter, microbial biomass and soil respiration were determined. Overstory and understory plants were noted. Variations in soil properties were greater along transects than between treated and untreated areas. Soil texture was coarser closer to the stream. Percent soil moisture, organic matter and microbial biomass increased away from the stream, but there was no strong pattern in pH. The lowest soil pH 5.55 was at 40 m from the stream in the untreated site. There were differences in vegetation between treated and untreated sites. In particular there were tall grasses closed to the stream where alders were girdled while no grasses occurred in the untreated site. We have interest in examining nitrogen dynamics in these soils.

Kerri Mikkelsen
College of Forest Resources
University of Washington
Box 352100
Seattle, WA 98195-2100
(206) 543-5769
knm5c@u.washington.edu

Historical Fire Frequency Comparison Between Riparian Zones and Adjacent Upslope Forest

The purpose of this study is to compare the historical fire frequency within a riparian zone to the fire frequency occurring in adjacent upslope forest. The study covers two distinct geographical locations: the Blue Mountains of eastern Oregon and the western slope of the Cascades Range in central Oregon. During the summers of 1997 and 1998, a total of 67 sites were sampled between the two locations. In the Blue Mountains, fire scar samples were collected from 19 riparian sites in the vicinity of the Dugout Creek Research Natural Area of the Malheur National Forest and from 16 riparian sites within the Baker City watershed of the Wallowa-Whitman National Forest. All 35 sites were paired with proximal upslope sites sampled by Emily Heyerdahl, University of Washington, in 1995. In the Cascades, fire scar samples were collected from 32 sites within the Upper Steamboat watershed of the Umpqua National Forest. Unlike in the Blue Mountains, prior sampling had not occurred in this area. Therefore, the 32 sites were divided into 16 riparian zone sites paired with adjacent upslope sites. In both areas, sampling was divided between small-sized streams and medium-sized streams. The riparian zone was defined as one tree length (approx. 50 meters) from a small-sized stream and two tree lengths (approx. 100 meters) from the high water level of a medium-sized stream. Distance was measured "over-ground" and from either side of the stream. In the Malheur and Wallowa-Whitman National Forests, samples were taken from both live trees and dead material (e.g., logs, stumps and short snags), whereas in the Umpqua National Forest, fire scar samples were taken solely from stumps and logs in recent clearcuts. Samples collected from each location are in the process of being analyzed.

(Funded by Cooperative Agreements PNW-97-5082-1-CA and PNW 93-0479 between the University of Washington and the USDA Forest Service, Pacific Northwest Research Station)

Diana Olson
College of Forest Resources
University of Washington
Box 352100
Seattle, WA 98195-2100
(206) 543-7940
dlolson@u.washington.edu

Comparison of the Hydraulic and Biologic Effects
of Large Woody Debris and an Engineered Alternative
in Stream Rehabilitation

This is a pilot study to examine the hydraulic and biological effects of placing single logs in lowland streams of Washington State. The test subjects are native large woody debris and an organic, engineered alternative to large woody debris. The hydraulic component of the study is to analyze the behavior of water around engineered large woody debris (ELWd^TM) and natural LWD. The placed wood acts as a stagnation point in fluid flow, which creates turbulence. The turbulence created by water flowing around ELWd^TM may be different than that created around native LWD, due to influences of shape, buoyancy and weight. The biological component involves an analysis of the populations of invertebrates and fish that become associated with LWD and ELWd ^TM. Differences in surface area and water flow may affect the abundance and distribution of invertebrates on the surface of the structures and in the substrate downstream. Additionally, differences in turbulence may change the quality of pool habitat downstream from the structures, which may be reflected in the distribution of fish species. The results of the experiment will help determine the effectiveness of an engineered alternative in stream restoration, before the structure is widely placed in western Washington.

Woody debris plays an important role in both physical and biological components of healthy stream ecosystems. Large woody debris increases the amount of food available and the quality of habitat for insectivorous fish (Karr, 1984). Woody debris often causes scour, which creates larger pools, while at the same time providing cover for fish. Invertebrates quickly utilize debris as a food source and as a substrate for colonization (Thorp et al., 1985; O'Conner, 1991). Therefore, adding debris to a plane bed system as part of a stream rehabilitation project should result in increased complexity of habitat and availability of invertebrates as a food resource for salmonids.

Unfortunately, the demand for wood components for restoration projects has increased the price of stumps, rootwads and logs. A single element can cost four to five hundred dollars, and placement of that element can cost an additional four to five thousand dollars. As these pieces become increasingly rare, a new solution must be developed for supplying the demand for wood in stream projects.

The engineered large woody debris consists of refuse from the timber industry that can be carried by hand and assembled on site. Like woody debris, the structure has a high hydraulic roughness and a high surface roughness to trap sediments and debris. Unlike large woody debris, ELWd^TM structures are hollow, have surfaces that are convoluted with gaps, and are non-cylindrical. The physical differences of the engineered structures may be significant when compared to native wood.

Unlike many restoration efforts, the effects of the engineered structures will be examined before being widely placed in stream projects. The idea of having prior knowledge of the effects the structure will have in a restoration project is important and significant. The information from this study may be used in determining the suitability of using engineered elements in a restoration project.

Jen O'Neal
School of Fisheries
University of Washington
Box 357980
Seattle, WA 98195-7980
jenoneal@fish.washington.edu

Anne Watts
College of Forest Resources
University of Washington
Box 352100
Seattle, WA 98195-2100
(206) 543-5506
arwatts@u.washington.edu

Relationship Between Total Suspended Solids and Turbidity in Urbanizing Streams in the Puget Lowlands

The replacement of forest with impervious surfaces during urbanization can have significant effects on hydrologic functions and water quality. A pilot study was conducted to analyze the relationship between turbidity and total suspended solids (TSS) in Puget Sound Lowland streams. Since turbidity is a measure of either the absorption or refraction of light of soil particles in the water column, it is assumed to be a surrogate measurement of the total suspended load. However, the exact relationship between these two parameters for a given region, watershed or stream is affected by many factors, including hydrology, soil conditions, geomorphology and the presence of impervious surfaces.

Water samples were hand-collected from 6 streams in the Puget Sound Lowlands during storms from September-December, 1998. Five stations were located in rural or forested areas in Redmond, Washington where addition of impervious surfaces will increase significantly over the next decade. Four of these five stations have flumes and remote data loggers that record stage, turbidity and temperature. A sixth station in urban north Seattle was also sampled. In addition, paired samples were drawn from streams with flumes to test for TSS differences between flumes and 'natural' riffles just upstream.

A linear regression model was applied to analyze the relationship between TSS and turbidity for each stream and for all the streams together. R² values for the individual streams ranged from 0.88 to 0.95, and for all streams together R²=0.88. These values show a strong relationship between turbidity and TSS, which generally compliments existing data from similar studies.

Paired samples were tested for differences in mean TSS via ANOVA for all streams together and paired t-test for individual streams. Results show no significant differences between mean TSS values for samples drawn in flumes and those drawn at an upstream 'natural' riffle (p-values ranging from 0.23 to 0.66).

James Packman
College of Forest Resources
University of Washington
Box 352100
Seattle, WA 98195-2100
(206) 543-5506
jpackman@u.washington.edu

Variable Influence of Lithology, Landform and Land Use on Mass Wasting Rates Across a Landscape, North Cascades, Washington

Mass wasting inventories of nine sub-watersheds within a 8,700 km2 basin in northwestern Washington were completed to investigate the influence of lithology, landform and land use on landslide occurrence and sediment delivery rates. Land-use changes associated with commercial forestry were entered into a GIS (ARC/INFO) for each time period during which landslides were inventoried. Mean landslide occurrence and associated sediment delivery rates were calculated for 28 different combinations of lithology, landform and land use. Weighting by the square-root of area, landform alone explained 50% of the variance in sediment delivery rates. Land-use association explained an additional 26%, and lithologic association another 8%. Landform was also the dominant factor influencing landslide occurrence rates. Although steep, stream-adjacent slopes occupied only 2-24% of the sub-basins, 75-96% of the sediment that was delivered to streams was associated with landslides originating in this landform type. Clearcut logging of inner gorges increased the sediment delivery rate to roughly four times the mean rate for inner gorges with mature stands.

Kari Paulson
Center for Streamside Studies
College of Forest Resources
University of Washington
Box 352100
Seattle, WA 98195-2100
(206) 543-6920
karipaul@earthlink.net

Biogeochemistry and Hydrology of a Forested Floodplain Back Channel: Riparian and Hyporheic Interactions

Complex interactions among riparian forests, subsurface flowpaths, and riverine dynamics provide the focus for this poster. Research described herein was designed to evaluate how riparian red alder (Alnus rubra) stands influence aquatic nutrient dynamics along a floodplain backchannel on the Queets River, WA. This study also explored the capacity of the backchannel to process nitrogen and phosphorus. Solute additions were conducted to quantify fluxes and label hyporheic waters. Reach-scale hydrology and nutrient processing patterns were investigated along 300 to 520 m of the backchannel. The backchannel was always a net gaining reach during low-flow summer conditions. As waters drained adjacent terraces, nutrient laden subsurface waters traveled into the hyporheic zone and mixed with advected surface waters. Terrace fluxes delivered 4.4 x 10^-3 to 1.9 x 10^-2 mg/s/m NO₃-N, 3.8 x 10^-4 to 3.4 x 10^-3 mg/s/m NH₄-N, and 3.4 x 10^-4 to 2.7 x 10^-3 mg/s/m Soluble Reactive Phosphorus under ambient conditions. Biotic and abiotic processing, before and after entrance into the surface water, removed 10 to 49 % NO₃-N, 25 to 96 % NH₄-N, and up to 91 % of SRP inputs. The capacity to remove nutrients varied along the reach, and despite the high assimilation capacity, there was a net import of nitrogen and phosphorus to the channel. An ammonium co-injection confirmed the high immobilization potential of the backchannel. Subsurface riparian inputs, which drain senescing red alder terraces, clearly supply both nitrogen and phosphorus to the backchannel. Forested floodplain heterogeneity drives complex biogeochemical processes that, in turn, control patterns of backchannel primary production.

Liz Ritzenthaler
College of Forest Resources
University of Washington
Box 352100
Seattle, WA 98195-2100
lizritz@u.washington.edu

Stream Habitat Assessment Protocols:
Evaluation of Urbanizing Streams and Watersheds
of the Puget Lowland, Western Washington State

The physical conditions of streams are important determinants of aquatic habitat quality. These stream conditions, or channel features, can be used to assess the relative health of streams in western Washington. Agencies rely on these assessments in managing the state's aquatic resources. Ideally, there would be a single accurate and reproducible protocol for evaluating different streams. However, this is not the case. Different agencies employ different assessment protocols, each of which varies in their choice of the particular channel features measured and their relative importance. For this reason, these protocols yield different views of habitat quality. These protocols are not necessarily comparable, and it is therefore not possible to combine all existing data into a comprehensive database of stream habitat quality.

This project had the overall goal of identifying and evaluating common protocols used by local agencies to assess stream habitat conditions in western Washington. We developed a set of recommendations for use by public agencies, to help design and execute stream-monitoring programs focused on the urban and urbanizing parts of the State. We selected six channel features typically monitored by local agencies in urbanizing lowland watersheds, and identified the parameters normally used to measure each of these features. We then determined the relative level of effort required to measure each of those parameters. Finally, we evaluated the relative merit of these parameters in answering three management questions that depend on characterizing the health of streams in urbanizing watersheds.

We found that although there is general agreement that the physical conditions of streams are important determinants of aquatic habitat quality, there is little agreement on the best way to measure or to characterize those physical conditions. Even though many agencies and volunteer groups are collecting tremendous amounts of stream-condition data, the region cannot assess comprehensively the status of its aquatic systems. This problem is compounded in urban and urbanizing areas, because most of the monitoring protocols currently in use have been developed for other purposes or in other settings, notably the forested slopes of the adjacent mountains.

Jenna Scholz
College of Forest Resources
University of Washington
Box 352100
Seattle, WA 98195-2100
(206) 543-5506
jscholz@u.washington.edu

Stand Structure and Crown Fire Risk in Eastside
Forest Riparian Zones

Riparian vegetation is often assumed to burn less frequently than upland vegetation in evaluations of fire hazard and in many cases may form a barrier to fire spread. This is due to the increased availability of moisture in riparian forests, which reduces their likelihood of carrying low severity ground fire. However, the complex multi-layered structure and high proportion of fire-sensitive species within riparian areas make these areas particularly susceptible to high severity fire under certain weather conditions. As a result of these structural and compositional differences, riparian vegetation may burn with much greater intensity than adjacent upland vegetation. Consequently, the risk of crown fire in riparian zones may be higher than in associated upland areas.

In this ongoing model-based study, the forest stand structures of paired riparian and upland plots are compared. Fireline intensities using extreme fire weather will be determined using the BEHAVE fire model and compared to the critical fireline intensity required for initiation of crown fire. Comparisons of potential fire behavior between riparian and upland sites and between forest types can then be made. Using the FVS (Forest Vegetation Simulator) growth model, various stand manipulations and their resulting effects on crown fire risk will also be evaluated.

Nate Williamson
College of Forest Resources
University of Washington
Box 352100
Seattle, WA 98195-2100
(206) 543-7940 nwilliam@u.washington.edu