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SFS Annual Meeting

Tuesday, June 4, 2024
13:30 - 15:00

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S24 New Approaches and Methods for Understanding and Improving Urban Waterways: A Global Perspective

13:30 - 13:45 | Independence Ballroom A | A HOLISTIC MODELING APPROACH TO RELATE HYDROLOGY AND ECOLOGY IN URBAN WATERSHEDS

6/04/2024  |   13:30 - 13:45   |  Independence Ballroom A

A holistic modeling approach to relate hydrology and ecology in urban watersheds The City of Austin Watershed Protection Department (WPD) has built thirteen watershed models covering about twenty square miles within and around the Full Purposed Jurisdiction of the City of Austin (COA). These models were constructed to simulate the hydrology of the watersheds under current land uses, impervious cover conditions, and soil types. The Gridded Surface Subsurface Hydrologic Analysis (GSSHA) system was used to build the watershed models which contained a surface water component paired with a groundwater component to simulate stream baseflow and infiltration. All models were run over a simulation period of eight years (2011 to 2018), resulting in hydrographs at points along the stream coincident with points at which ecological data was collected. The ecological data was used to create pollution tolerance metrics. A side benefit of these watershed models is that they can be used to create infiltration maps that estimate baseflow in streams. The coincident hydrologic and ecological data were then used to train a Deep Learning (DL) model. This model allows watershed managers to estimate ecological metrics at stream locations that have not been observed and then identify ecological problems at a granular spatial scale.

Abel Porras (Primary Presenter/Author), City of Austin Watershed Protection Department, abel.porras@austintexas.gov;

Young-Hoon Jin (Co-Presenter/Co-Author), City of Austin Watershed Protection Department, younghoon.jin@austintexas.gov;

Yazmin Avila Flores (Co-Presenter/Co-Author), City of Austin Watershed Protection Department, yazmin.avila@austintexas.gov;

Andrew Chu (Co-Presenter/Co-Author), City of Austin Watershed Protection Department, andrew.chu@austintexas.gov;

Harshita Mahaseth (Co-Presenter/Co-Author), City of Austin Watershed Protection Department, harshita.mahaseth@austintexas.gov;

Edward Peacock (Co-Presenter/Co-Author), City of Austin Watershed Protection Department, ed.peacock@austintexas.gov;

Julia Siegmund (Co-Presenter/Co-Author), City of Austin Watershed Protection Department, julia.siegmund@austintexas.gov;

13:45 - 14:00 | Independence Ballroom A | WHERE DOES LAND USE MATTER MOST? CONTRASTING LAND USE EFFECTS ON RIVER QUALITY AT DIFFERENT SPATIAL SCALES

6/04/2024  |   13:45 - 14:00   |  Independence Ballroom A

Where Does Land Use Matter Most? Contrasting Land Use Effects on River Quality at Different Spatial Scales Understanding the influence of land-use activities on river quality has been a key focus of river monitoring programs worldwide. However, defining which land-use spatial scale is relevant remains elusive. In this study, we contrasted the influence of land-use on river quality using three types of land-use estimators, namely circular buffers around a monitoring site, circular buffers upstream of the monitoring site and the entire watershed area upstream of the monitoring site. The land-use percentage compositions within the Usa-Kikuletwa River catchment in northeastern Tanzania were quantified using Landsat-8 satellite images with a maximum mapping resolution of 30m. Redundancy analysis and generalized-linear models were used to evaluate the influence of land-use on macroinvertebrate assemblages and water quality at different spatial scales in the dry and wet seasons. Overall, variation in water quality, macroinvertebrate taxon richness, Chao-1 and TARISS-score could be explained by land-use of the entire watershed area upstream of the monitoring site in the dry and wet seasons. However, macroinvertebrate abundances showed strong links with more local land-use patterns within 100m and 2km radii. Circular buffers upstream of monitoring sites were more informative for macroinvertebrate assemblages than circular buffers around the monitoring sites. However, the latter did correlate well with physico-chemical water quality variables. Land-use variables correlated across spatial scales (i.e., 100m up to 2km radii), but not with the land-use in the entire watershed area above the monitoring site. Our results indicate that water quality variables and macroinvertebrates may respond differently to land-use effects at different spatial scales.

Grite Nelson Mwaijengo (Primary Presenter/Author), The Nelson Mandela African Institution of Science and Technology, grite.nelson@nm-aist.ac.tz;

Luc Brendonck (Co-Presenter/Co-Author), KU Leuven, luc.brendonck@kuleuven.be ;

Karoli Njau (Co-Presenter/Co-Author), The Nelson Mandela African Institution of Science and Technology, Karoli.njau@nm-aist.ac.tz;

Bram Vanschoenwinkel (Co-Presenter/Co-Author), Vrije Universiteit Brussel, Bram.jasper.vanschoenwinkel@vub.be;

14:00 - 14:15 | Independence Ballroom A | DEVELOPING A TIERED APPROACH FOR ASSESSMENT OF BIOLOGICAL AND ECOLOGICAL STREAM CONDITION

6/04/2024  |   14:00 - 14:15   |  Independence Ballroom A

DEVELOPING A TIERED APPROACH FOR ASSESSMENT OF BIOLOGICAL AND ECOLOGICAL STREAM CONDITION Stream ecosystems are a major focus of management activities, ranging from aquatic ecosystem restoration to regulatory mitigation. Historically, stream assessments have relied on techniques used for quantifying and evaluating aquatic habitat. These assessments are often based on ecosystem structure and evaluate conditions for a target species or set of physical parameters. However, these models often fail to capture the structure, function, and dynamic processes of stream ecosystems. We developed a framework for functional stream assessment aligned with different levels of effort. This framework is designed to provide a consistent approach for stream assessment at any scale of analysis and can be tailored to local needs and project constraints. We reviewed existing approaches for evaluating stream ecosystem structure and function, ranging from qualitative techniques to empirical data collection. We compiled tools into a framework for assessing stream outcomes at three levels of effort, here discussed as Tiers. Currently, there are few Tier 1 tools, which rely on desktop analyses and are widely applicable for reconnaissance-level evaluation of biological functions. Tier 2 approaches are more common, using rapid field assessment to evaluate site performance and conditions. Tier 3 approaches are the most numerous, relying on empirical biological monitoring data and tailored to regional needs. We analyzed the various existing tools within each tier group currently in use, identifying both strengths and gaps in evaluation and resulting opportunities for creation of future tools. This framework is intended to be widely applicable but also flexible to project objectives and the desired level of effort.

Leanne Stepchinski (Primary Presenter/Author), ORISE Postdoctoral Fellow at U.S. Army Corps of Engineers Engineer Research and Development Center – Environmental Laboratory, leanne.m.stepchinski@usace.army.mil;

Garrett Menichino (Co-Presenter/Co-Author), Environmental Laboratory, U.S. Army Engineer Research and Development Center, Garrett.T.Menichino@usace.army.mil;

Kyle McKay (Co-Presenter/Co-Author), Environmental Laboratory, U.S. Army Engineer Research and Development Center, kyle.mckay@usace.army.mil;

14:15 - 14:30 | Independence Ballroom A | OPTIMA-DERIVED REGIONAL POLLUTION TOLERANCE INDEX PROVIDES HIGHER RESOLUTION URBAN STRESSOR RESPONSE THAN TRADITIONAL APPROACH

6/04/2024  |   14:15 - 14:30   |  Independence Ballroom A

Optima-derived regional Pollution Tolerance Index provides higher resolution urban stressor response than traditional approach A growing body of literature suggests that for stream biota, locally derived Pollution Tolerance Indices (PTIs) yield stronger relationships with environmental stressors than regionally or nationally derived PTIs. In pursuit of higher resolution relationships with anthropogenic impacts, the City of Austin developed locally derived PTIs for benthic macroinvertebrates and diatoms in relation to specific conductance, total nitrogen, total phosphorus, and impervious cover using 22 years of historic monitoring data and the R package ‘optimos.prime’. We then assessed the strength of the response of the Austin-PTI-based metrics to changes in environmental stressors relative to the response of previously utilized biological community metrics. The Austin-PTI-based metrics outperformed 54 other metrics, including metrics based on PTIs derived in other ecoregions. This analysis has generated a powerful new set of localized metrics derived from the empirical responses of biological communities to anthropogenic stressors in the Austin area. These processes are transferable to any entity seeking to establish localized PTIs or improve responsiveness of a biological multi-metric index.

Julia Siegmund (Primary Presenter/Author), City of Austin Watershed Protection Department, julia.siegmund@austintexas.gov;

14:30 - 14:45 | Independence Ballroom A | BIOTIC INTEGRITY IMPROVING ACROSS AN URBAN GRADIENT DESPITE CONTINUED DEVELOPMENT

6/04/2024  |   14:30 - 14:45   |  Independence Ballroom A

BIOTIC INTEGRITY IMPROVING ACROSS AN URBAN GRADIENT DESPITE CONTINUED DEVELOPMENT Stream conditions in King County, WA, are generally improving, according to increasing benthic index of biotic integrity (B-IBI) scores. Of 120 sites sampled annually since 2002, B-IBI scores are significantly improving at 25%, whereas only 3% of sites are significantly declining. These improvements have occurred despite continued development within many of the basins, suggesting that recent development has impacted stream communities less than older development. Accordingly, we were interested in whether the response of aquatic macroinvertebrate communities to development depends on when that development occurred. By examining when the development in a basin occurred, we assessed indirectly whether the collective efforts to protect streams have had a positive effect or at least prevented harm. We characterized each basin by when it was developed and found earlier-developed basins generally had worse B-IBI scores than basins with the same amount but more recent development. The extent of impervious area within a basin was still the best single predictor of B-IBI scores, but when that impervious area was built was also statistically significant and explained 5% of the variation. The effect was ecologically meaningful as well: on average, sites in basins with the oldest development scored 10 to 20 points lower (on a 0-100 scale) than sites in basins with the same amount but relatively newer development. The results suggest efforts to minimize impacts of development, including increased treatment and control of stormwater, may have been somewhat successful.

Kate Macneale (Primary Presenter/Author), King County - Water and Land Resources, kate.macneale@kingcounty.gov;

Beth Sosik (Co-Presenter/Co-Author), King County - Water and Land Resources, esosik@kingcounty.gov;

14:45 - 15:00 | Independence Ballroom A | WADING AND RIPARIAN BIRD COMMUNITIES MAY RESPOND DIFFERENTLY TO REDUCTIONS IN EFFLUENT DISCHARGES IN CHANNELIZED VS. UNCHANNELIZED URBAN RIVERS

6/04/2024  |   14:45 - 15:00   |  Independence Ballroom A

Wading and riparian bird communities may respond differently to reductions in effluent discharges in channelized vs. unchannelized urban rivers How will wading and riparian bird communities change if river flows decrease or run dry? Portions of the channelized Los Angeles River and unchannelized Santa Clara River in Southern California, U.S.A. now flow perennially due to effluent discharges. However, water managers are preparing to reduce these discharges and expand wastewater recycling to address water supply needs, with uncertain consequences for riverine birds. We designed a study to explore the role of effluent in shaping riverine bird communities. In this presentation, we will focus on seasonal bird data that we collected at 14 L.A. River and Santa Clara River sites between June 2022 and January 2024. We detected more than 140 total species. We are characterizing the relationships between changing flows and bird composition, with regards to their feeding and nesting habits and riverine dependence (i.e., open water, riparian, and upland). The L.A. River supported more open water-dependent species, particularly downstream of effluent discharges along its concrete-lined reaches, whereas the Santa Clara River supported more riparian-dependent species; a reduction in effluent discharges may have more immediate impacts on the LA River’s species that depend on open water habitats for foraging and breeding. The impacts of flow changes on birds carry both ecological and social meanings, as birds are important to many people. Our study will illuminate how flow decision-making can shape riverine bird communities and support people’s connections with those communities.

Melissa von Mayrhauser (Primary Presenter/Author), University of California, Berkeley, mvonmayrhauser@berkeley.edu;

Raphael Mazor (Co-Presenter/Co-Author), Southern California Coastal Water Research Project, raphaelm@sccwrp.org;

Albert Ruhi (Co-Presenter/Co-Author), Department of Environmental Science, Policy, and Management, University of California, Berkeley, albert.ruhi@berkeley.edu;

Ted Grantham (Co-Presenter/Co-Author), University of California, Berkeley, tgrantham@berkeley.edu;