ABSTRACT:

This data set contains measurements for discharge in cfs and cms, stream temperature in °C , dissolved oxygen (DO) in mg/L and %/L, total dissolved solids (TDS) in µs/cm, pebble count, and geomorphic condition, at sites in the Weber River Basin and Bear River Basin. Discharge was measured using a Marsh McBurney hand-held flowmeter. DO, TDS, and stream temperature were measured using a YSI Pro 2030 water quality probe. Pebble count was conducted using a modified Wolman procedure where a random pebble is picked up every step diagonally across a stream in a zig-zag pattern until at least 100 pebbles are measured. The pebble is then measured to obtain size and recorded. Geomorphic condition was assessed visually by taking note of conditions such as stream complexity (presence or lack of pools, riffles, meandering thalweg etc.), percent shade on stream, flow and depth variability, bank stability, access to floodplain, wood recruitment, unnatural barriers and condition and quantity of riparian vegetation. Based on the these conditions, a classification of excellent, good, moderate, or poor was assigned. Atmospheric pressure, wind speed and air temperature were measured with a Kestrel handheld weather meter, cloud cover was assessed visually. A site key in addition to the date, time and location (latitude/longitude and UTM) is included. Not all sites have values for discharge and pebble count due to hazardous conditions.

ABSTRACT:

In-stream barriers, such as dams, culverts and diversions alter hydrologic processes and aquatic habitat. Removing uneconomical and aging in-stream barriers to improve stream habitat is increasingly used in river restoration. Previous barrier removal projects focused on score-and-rank techniques, ignoring cumulative change and spatial structure of barrier networks. Likewise, most water supply models prioritize either human water uses or aquatic habitat, failing to incorporate both human and environmental water use benefits. In this study, a dual objective optimization model prioritized removing in-stream barriers to maximize aquatic habitat connectivity for trout, using streamflow, temperature, channel gradient, and geomorphic condition as indicators of aquatic habitat suitability. Water scarcity costs are minimized using agricultural and urban economic penalty functions, and a budget constraint monetizes costs of removing small barriers like culverts and diversions. The optimization model is applied to a case study in Utah’s Weber River Basin to prioritize removing barriers most beneficial to aquatic habitat connectivity for Bonneville cutthroat trout, while maintaining human water uses. Solutions to the dual objective problem quantify and graphically show tradeoffs between connected quality-weighted habitat for Bonneville cutthroat trout and economic water uses. Removing 54 in-stream barriers reconnects about 160 km of quality-weighted habitat and costs approximately $10 M, after which point the cost effectiveness of removing barriers to connect river habitat decreases. The set of barriers prioritized for removal varied monthly depending on limiting habitat conditions for Bonneville cutthroat trout. This research helps prioritize barrier removals and future restoration project decisions within the Weber Basin. The modeling approach expands current barrier removal optimization methods by explicitly including both economic and environmental water uses and is generalizable to other basins.

ABSTRACT:

We created a shapefile of Utah's Cache Valley street water conveyance system using ArcGIS. This included gutters, canals, and discontinued canals that transport secondary water to customers. This data collection and research supports coupled human-natural systems research because it connects human and environmental water systems. The purpose of our data collection and mapping is to support future analysis of street gutters and canals as unique secondary water delivery systems. We georeferenced the network of street water conveyance in summer 2016 that delivers secondary water. We drove, cycled, and walked Logan streets and marked those with observed water conveyance through gutters and canals on a printed map that was then transferred into an ArcGIS shapefile. To accurately determine which street gutters are part of the irrigation water delivery system, we contacted Cache County irrigation companies to receive guidance and feedback.

ABSTRACT:

In-stream barriers, such as dams, culverts and diversions alter hydrologic processes and aquatic habitat. Removing uneconomical and aging in-stream barriers to improve stream habitat is increasingly used in river restoration. Previous barrier removal projects focused on score-and-rank techniques, ignoring cumulative change and spatial structure of barrier networks. Likewise, most water supply models prioritize either human water uses or aquatic habitat, failing to incorporate both human and environmental water use benefits. In this study, a dual objective optimization model prioritized removing in-stream barriers to maximize aquatic habitat connectivity for trout, using streamflow, temperature, channel gradient, and geomorphic condition as indicators of aquatic habitat suitability. Water scarcity costs are minimized using agricultural and urban economic penalty functions, and a budget constraint monetizes costs of removing small barriers like culverts and diversions. The optimization model is applied to a case study in Utah’s Weber River Basin to prioritize removing barriers most beneficial to aquatic habitat connectivity for Bonneville cutthroat trout, while maintaining human water uses. Solutions to the dual objective problem quantify and graphically show tradeoffs between connected quality-weighted habitat for Bonneville cutthroat trout and economic water uses. Removing 54 in-stream barriers reconnects about 160 km of quality-weighted habitat and costs approximately $10 M, after which point the cost effectiveness of removing barriers to connect river habitat decreases. The set of barriers prioritized for removal varied monthly depending on limiting habitat conditions for Bonneville cutthroat trout. This research helps prioritize barrier removals and future restoration project decisions within the Weber Basin. The modeling approach expands current barrier removal optimization methods by explicitly including both economic and environmental water uses and is generalizable to other basins.

ABSTRACT:

Representing urban water demands economically is useful to understand how anticipated changes like population growth, conservation, water development, climate change, and environmental water demands may affect water deliveries and scarcity. Utah is the second driest state in the nation, while per capita water use is near the highest in the nation, averaging 167 gallons per person per day. This implies that creative water management will be ongoing in Utah’s future. Urban economic loss functions are estimated using residential demand functions for Utah’s Wasatch Front Metropolitan Area, which includes Logan, Salt Lake City, Ogden, Layton, Provo, and Orem urban regions. Water price, volume of water applied at that price, urban population, and price elasticity data are presented. Results show seasonal residential water demand functions and seasonal urban (residential, industrial, institutional, and commercial) economic loss functions for Logan, Ogden, Salt Lake City, and Provo metropolitan areas. Limitations to this method are outlined and discussion focuses on estimating urban water demand functions and potential economic losses input into hydro-economic models and ecological-economic models to evaluate promising solutions to Utah’s persistent water problems.

ABSTRACT:

Data collection on water the potential for water markets to address Great Salt Lake water conservation needs.

To create cost estimates we build on the approach of Edwards et al (2017) to create conservation cost curves estimates for each of the Bear River, Weber River, and Jordan River watersheds. We designate potential conservation measures as occurring in the agricultural or urban sectors. Estimates come from other sources and are then applied to the case at hand. Overall we estimate the conservation potential and cost savings of 15 measures, shown in the table. While the list is not comprehensive, efforts were made to include the measures likely to be implemented.

Conservation measures by category.
Urban Residential: low-flow toilets
Residential: low-flow showers
Residential: high-efficiency clothes washers
Residential irrigation: rainwater harvesting
Residential irrigation: watering at night
Residential irrigation: scheduling
Residential irrigation: partial turf conversion
Institutional irrigation: watering at night
Institutional irrigation: scheduling
Commercial irrigation: watering at night
Commercial irrigation: scheduling
Secondary wastewater reuse
Agriculture Conversion to sprinkler irrigation
Improved irrigation efficiency
Canal piping

For each conservation we estimate the quantity of water that could be conserved as well as the cost of conserving that water. We create a low, baseline, and high estimate of costs for each measure. We also create a high, baseline, and low estimate of the amount of water made available by each measure. The low cost estimate is combined with the high water availability estimate to arrive at an upper bound of each water supply curve; similarly the high-cost and low water-availability estimates are combined to create a lower-bound.

ABSTRACT:

This report details a model that uses a nonlinear penalty function in a linear reservoir optimization model to identify a monthly reservoir release strategy that maximizes end-of-water-year storage in Island Park Reservoir, while satisfying habitat and flow requirements for fish and anglers. Using historic hydrologic data, I explore how strategies for reservoir release, storage, and irrigation reduction change across varying hydrologic regimes (wet, average, dry) and environmental flow requirements (800, 1000, 1200 cfs).

ABSTRACT:

Globally changing temperature and precipitation patterns are causing rapid changes stream temperatures, which in turn drive changes in the life histories and distributions of aquatic biota. However, large-scale stream temperature datasets have not been developed, and observational data remains limited. In order to better understand how ongoing thermal regime changes impact aquatic species, managers and researchers need better methods of quantifying stream temperatures at large spatial scales. Here, a linear regression model is used to develop a relationship between air and stream temperature, then is used to predict stream temperatures across the state of Utah in the month of August. Model validity was assessed by examining goodness of fit to observation data using R², Nash-Sutcliffe Efficiency index, and root mean square error-observations standard deviation ratio (RSR). Impact of outliers were assessed by examining mean absolute error (MAE), root mean square error (RMSE), and residuals. The approach presented here contributes to the well-described linear air/stream temperature model by providing a study of its performance at large spatial scales.

ABSTRACT:

One of the greatest threats to Great Salt Lake wetlands is the invasion of Phragmites australis. Recent research has highlighted effective control strategies for Phragmites, however natural recolonization of native plants needed to support wetland functions has been limited. Seeding is a feasible restoration option, however seedling mortality is often high. Understanding the mechanisms that drive early seedling outcomes by quantifying regeneration traits can improve our ability to manipulate and predict restoration actions. Additionally, managers involved in wetland restoration need to know how many seeds to sow, which sites should be prioritized for restoration, and when they should seed. I developed a simulation model to explore changes in native and invasive seed germination across initial seeding density, restoration site, and seasonal timing scenarios. Additionally, I incorporated the influence of seed mass on native species germination into my model. This approach represents a starting point for developing an important management tool that can be used to identify targeted, cost-effective wetland restoration strategies following Phragmites treatment.

ABSTRACT:

Watershed-scale stream temperature models are often one-dimensional because they require fewer data and are more computationally efficient than two- or three-dimensional models. However, one-dimensional models assume completely mixed reaches and ignore small-scale spatial temperature variability, which may create temperature barriers or refugia for cold-water aquatic species. Fine spatial and temporal resolution stream temperature monitoring provides information to identify river features with increased thermal variability. We used distributed temperature sensing (DTS) to observe small-scale stream temperature variability, measured as a temperature range through space and time, within two 400 meter reaches in summer 2015 in Nevada’s East Walker and mainstem Walker Rivers. Thermal infrared (TIR) aerial imagery collected in summer 2012 quantified the spatial temperature variability throughout the Walker Basin. We coupled both types of high resolution measured data with simulated stream temperatures to corroborate model results and estimate the spatial distribution of thermal refugia for Lahontan cutthroat trout and other cold-water species. Temperature model estimates were within the DTS measured temperature ranges 21% and 70% of the time for the East Walker River and mainstem Walker River, respectively, and within TIR measured temperatures 17%, 5%, and 5% of the time for the East Walker, West Walker, and mainstem Walker Rivers, respectively. DTS, TIR, and modeled stream temperatures in the mainstem Walker River nearly always exceeded the 21°C optimal temperature threshold for adult trout, usually exceeded the 24 °C stress threshold, and could exceed the 28 °C lethal threshold for Lahontan cutthroat trout. Measured stream temperature ranges bracketed ambient river temperatures by -10.1 to +2.3 °C in agricultural return flows, -1.2 to +4 °C at diversions, -5.1 to +2 °C in beaver dams, -4.2 to 0 °C at seeps. To better understand the role of these river features on thermal refugia during warm time periods, the respective temperature ranges were added to simulated stream temperatures at each of the identified river features. Based on this analysis, the average distance between thermal refugia in this system was 2.8 km. While simulated stream temperatures are often too warm to support Lahontan cutthroat trout and other cold-water species, thermal refugia may exist to improve habitat connectivity and facilitate trout movement between spawning and summer habitats. Overall, high resolution DTS and TIR measurements quantify temperature ranges of refugia and augment process-based modeling.

ABSTRACT:

Planning and constructing hydropower dams have historically taken precedence over analyzing their environmental effects. In Mekong riparian countries, hydropower development provides energy, but also threatens biodiversity, ecosystems, food security, and an unparalleled freshwater fishery. The Sekong, Sesan, and Srepok Rivers (3S Basin) are major tributaries to the Lower Mekong River (LMB), making up 10% of the Mekong watershed but supporting nearly 40% of the fish species of the LMB. Forty-five dams have been built, are under construction, or are planned in the 3S Basin. We completed a meta-analysis of aquatic and riparian environmental losses from current, planned, and proposed hydropower dams in the 3S and LMB using 46 papers and reports from the past three decades. Proposed mainstem Stung Treng and Sambor dams were not included in our analysis because Cambodia recently announced a moratorium on mainstem Mekong River dams. More than 50% of studies evaluated hydrologic change from dam development, 33% quantified sediment alteration, and 30% estimated fish production changes. Freshwater fish diversity, non-fish species, primary production, trophic ecology, and nutrient loading objectives were less commonly studied. We visualized human and environmental tradeoffs of 3S dams from the reviewed papers. Overall, Lower Sesan 2, the proposed Sekong Dam, and planned Lower Srepok 3A and Lower Sesan 3 have considerable environmental impacts. Tradeoff analyses should include environmental objectives by representing organisms, habitats, and ecosystems to quantify environmental costs of dam development and maintain the biodiversity and extraordinary freshwater fishery of the LMB.

ABSTRACT:

Methods that accurately identify suitable aquatic habitat with minimal complexity are need to inform resource management. Habitat suitability models intersect environmental variables to predict habitat quality, but previous approaches are spatially and ecologically limited, and are rarely validated. This study estimated aquatic habitat at large spatial scales with publicly-available national datasets. We evaluated 15 habitat suitability models using unique combinations of percent mean annual discharge (MAD), velocity, gradient, and stream temperature to predict monthly habitat suitability for Bonneville Cutthroat Trout and Bluehead Sucker in Utah. Environmental variables were validated with observed instream conditions and species presence observations verified habitat suitability estimates. Results indicated that simple models using few environmental variables best predict habitat suitability. Stream temperature best predicted Bonneville Cutthroat Trout presence, and gradient and percent MAD best predicted Bluehead Sucker presence. Additional environmental variables improved habitat suitability accuracy in specific months, but reduced overall accuracy.

ABSTRACT:

Water management usually considers economic and ecological objectives, and involves tradeoffs, conflicts, compromise, and cooperation among objectives. Pareto optimality often is championed in water management, but its relationships with the mathematical representation of objectives, and implications of tradeoffs for Pareto optimal decisions, are rarely examined. We evaluate the mathematical properties of optimized tradeoffs to identify promising regions for compromise, suggest strategies for reducing conflicts, and better understand whether decision-makers are more or less likely to cooperate over environmental water allocations. Cooperation and compromise among objectives can be easier when tradeoff curves are concave and more adversarial when tradeoff curves are convex. “Knees”, or areas with maximum curvature, bulges, or breakpoints in concave Pareto frontiers, suggest more promising areas for compromise. Evaluating the shape of Pareto curves based on each objective’s performance function can screen for the existence of knees amenable to compromise. We explore water management and restorations actions that improve and shift the location and prominence of knees in concave Pareto frontiers. Connecting river habitats and other non-flow management actions may add knees on locally concave regions of Pareto frontiers. Managing multiple streams regionally, rather than individually, can sometimes turn convex local tradeoffs into concave regional tradeoffs more amenable to compromise. Overall, this analysis provides a deep investigation of how the shape of tradeoffs influences the range and promise of decisions to improve performance, and illustrates that management actions may encourage cooperation and reduce conflict.

ABSTRACT:

Aquatic habitat suitability models are increasingly coupled with water management models to estimate environmental effects of water management. Many types of habitat models exist, but there are no standard methods to compare predictive performance of habitat model types for use with water management models. In this study, we compared three common aquatic habitat model types: a hydraulic-habitat model, a habitat threshold model, and a geospatial model. Each of the models predicted native Bonneville Cutthroat Trout distribution in the Bear River Watershed (Utah, Idaho, and Wyoming, USA) at a monthly timestep. We compared the differences in predictive performance among models by validating 1) environmental predictors of the models with field observations from summer 2022, using the coefficient of determination (R²), Nash–Sutcliffe efficiency (NSE) index, and percent bias (PBIAS) and 2) habitat suitability estimates generated by each model with fish presence data and three accuracy metrics developed for this study. Validation of environmental predictors revealed observed conditions were not well represented by any of the three models—a function of either outdated, incorrect, or over-generalized input data. Validation of habitat suitability predictions using Bonneville Cutthroat Trout presence data showed the habitat threshold model most accurately classified fish presence observations in suitable habitat, but suitable habitat was likely overpredicted. While more precise habitat modeling methods may be useful to support generalized habitat estimates for native fish, overall, simple models, like the habitat threshold model, are promising for incorporating ecological objectives into water management models.

ABSTRACT:

Dams and reservoirs are often needed to provide environmental water and maintain suitable water temperatures for downstream ecosystems. We evaluate if water allocated to the environment, with storage to manage it, might allow environmental water to more reliably meet ecosystem objectives than a proportion of natural flow. We use a priority-based water balance operations model and a reservoir temperature model to evaluate 1) pass-through of a portion of reservoir inflow versus 2) allocating a portion of storage capacity and inflow for downstream flow and stream temperature objectives. We compare trade-offs to other senior and junior priority water demands. In many months, pass-through flows exceed the volumes needed to meet environmental demands. Storage provides the ability to manage release timing to use water efficiently for environmental benefit, with a co-benefit of increasing reservoir storage to protect cold-water at depth in the reservoir.

ABSTRACT:

The Measurement Infrastructure Gap Analysis in Utah’s Great Salt Lake Basin was a comprehensive inventory and analysis of existing diversion and stream measurement infrastructure along 19 primary river systems, as well as a preliminary investigation of measurement infrastructure gaps around Great Salt Lake proper. The purpose of this “Gap Analysis” was to develop methods to identify and prioritize areas throughout the Great Salt Lake basin where new or updated measurement infrastructure is needed to serve diverse objectives. The following gaps were identified: (1) existing measurement infrastructure quality and completeness gaps, (2) stakeholder identified gaps, and (3) potential spatial gaps in hydrologic understanding. By adapting the prioritization schema originally presented in the Colorado River Metering and Gaging and Gap Analysis to equally weight these three gap types at the HUC12 scale, a flexible framework for prioritizing new or updated measurement infrastructure in areas with large cumulative measurement gaps was developed, and high, medium, and low priority HUC12s were identified.

Results showed that 250 diversion and 28 stream measurement devices along primary systems had at least one quality and/or completeness gap. The most common quality and completeness gaps were insufficient device types, lack of telemetry, and data record interval. Stakeholders suggested 50 instances of new or updated diversion measurement infrastructure, 95 instances of new or updated stream measurement infrastructure, and 39 recommendations for continued funding of existing measurement infrastructure—totaling 185 stakeholder-identified gaps. To provide a spatially consistent approach to identifying potential gaps in hydrologic understanding, geospatial datasets describing features or attributes that can impact local hydrology were used to identify measurement gaps at the HUC12 scale. Among HUC12s that overlapped with the river systems included in this analysis, HUC12s with the greatest number of potential spatial gaps were in the Bear River sub-basin and near reservoirs in the Weber River sub-basin.

Based on the prioritization schema applied to synthesize these three gap types, there were 52 HUC12s along primary systems classified as high priority for measurement improvement. Of the 250 existing diversion and 28 stream measurement devices with at least one quality and/or completeness gap, 217 and 10 devices, respectively, were located within high priority HUC12s. Most stakeholder-identified gaps identified in the Weber and Jordan River sub-basins also fell within high-priority HUCs. Eighteen unique agencies suggested new or updated measurement infrastructure or continued funding of existing measurement infrastructure in high-priority HUC12s, demonstrating some consensus regarding measurement gaps in critical areas. There were 6 high priority HUC12s with no existing measurement infrastructure quality and completeness gaps, and 11 high priority HUC12s with no stakeholder-identified gaps. High priority HUC12s highlighted only due to potential spatial gaps may warrant additional investigation to further understand potential measurement gaps in these HUC12s.

Because the prioritization schema applied equally weighted all three gap types, it likely does not fully represent the diverse missions and priorities of different stakeholder groups. To facilitate an adaptable approach to prioritize measurement gaps within the Great Salt Lake basin, raw data for each of the three gap types are provided to allow varied prioritization schemes to be developed by weighting gap types differently or considering subsets of data. These data provide the basis for stakeholders within the Great Salt Lake basin to collectively prioritize future investments in gaging infrastructure and better manage water throughout the Great Salt Lake basin.