Session 3 | Wednesday, November 10 | 1:00 PM - 2:30 PM EST

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Virtual Revolution, Not Evolution: How do We Get Lasting Change While Ensuring Productive Agriculture and Good Water Quality?

Moderators: Lara Fowler

Presenters:

• Lara Fowler, Penn State University
• Paul Ferraro, Johns Hopkins University (C-BEAR)
• Mark Masters, Albany State (ACF Stakeholders, NRCS Advisory Board)
• Lisa Schulte Moore, Iowa State (Prairie STRIPs, C-CHANGE projects)
• Adam Tarr, US Senate Committee on Agriculture
• James P. Dobrowolski, National Institute for Food and Agriculture, USDA
Ensuring healthy and productive agriculture while meeting water quality goals is a serious challenge across the United States. Our toolkit for achieving water quality goals depends on a toolkit of programs and practices that become an alphabet soup: EQIP, CREP, and more. As we look at current needs and future changes, what can we do to update our toolkit going forward, perhaps as part of the next Farm Bill? What might a revolution in management practices look like, versus an evolution of the status quo? For example, should new programs place additional emphasis on technical or financial assistance? What policy or incentive structures most encourage persistence of initial conservation practice adoption? Join us for a panel discussion of what could be used to foster such a revolution.

Utilizing and Developing Open-access Water Data Tools and Resources

Moderator: Lilli Watson

Presenters:

• Adel Abdallah and Ryan James, Western States Water Council, "WaDE Water Rights and Water Use Data Standardization via WaDE’s Water Data Hub"
Water rights in the western eighteen states are based on the prior appropriation doctrine “First in time, first in right”. Each water right has a priority date and allocated amount of water (based on a volumetric quantity or a flow rate) with one or many designated beneficial uses such as agriculture or urban use. Each state administers and regulates its water rights independently. Water use is also reported or estimated by each state. Thus, access to water rights and water use data in a watershed spanning multiple states is cumbersome due to different access protocols, different structures, and terminology to describe data. The Western States Water Council’s (WSWC) Water Data Exchange (WaDE) program works with its 18 member states as a hub that provides web services with streamlined access to water rights and water use data. WaDE 2.0 is built using an agreed-upon data dictionary and schema that reconciles syntactic (e.g., structural) differences and addresses semantic differences through a shared, controlled vocabulary adopted by participating data providers. WaDE 2.0 is deployed in Microsoft Azure SQL Server Database and supports Rest web services and data visualization dashboards. This talk will overview the WaDE 2.0 program, describe its architecture, and web services to access its geospatial and time-series data. The talk will demonstrate its prototype dashboard with example data analysis and insights on water rights and water use in many parts of the Western United States. WaDE data services will complement and integrate with other national water data services such as the US Geological Survey (USGS) stream gages, Bureau of Reclamation Information Sharing Environment (RISE) for its reservoirs and canals, and Environmental Protection Agency’s (EPA) water quality data services. As part of this integration, the WaDE team is working with the Internet of Water and USGS groups on connecting WaDE to the Geoconnex project, which includes indexing WaDE data with the Hydro Network-Linked-Data-Index (NLDI) tool. Geoconnex will provide permanent identifiers to all sites that have data in WaDE and generalized landing pages that have common metadata to allow their discovery. NLDI will provide data query capabilities upstream or downstream of water sites in WaDE and will index sites with USGS, Reclamation, and EPA data services. The western US has over-allocated its water resources and future demand shortages due to extended droughts and demand growth have the potential to open water markets and water rights transfers. Centralized and consistent access to water rights and water use data in the west can facilitate such process and increase its transparency.


• Kyle Onda, Internet of Water, "Geoconnex.us: A Technical Framework for Discovering Water Data from Diverse Sources"
Geoconnex is a framework being developed by the IoW team in partnership with the USGS that connects structured water data sets in a distributed linked data system for improved discoverability. The overall goal of this project is to establish a technical baseline for a contributor-based system of regularly-harvested (or crawled) cross-referenced metadata. This requires two interdependent components: 1) the water data community to publish detailed machine-readable and cross-referenced metadata (linked data) and 2) a central crawler / harvester that can catalog all linked data from (1) into a single knowledge graph which will act as part of an index for search engines and other data discovery tools. In this project, a persistent identifier registry (https://geoconnex.us) for environmental features and monitoring locations was deployed, and a demonstration set of reference web content about environmental features including, but not limited to, watershed boundaries, stream reaches, aquifers, known monitoring locations, administrative geographies, and water-related infrastructure locations (dams, bridges, etc.) that data-publishing organizations can link to was published. In addition, key data providers including federal and state agencies and NGOs were engaged with to publish data about their monitoring locations in a similar manner, including links to the above reference features using persistent identifiers. A harvester is being piloted to gather all of this metadata and infer the linkages between them, and a demonstration search engine is also being deployed to help humans and machines navigate this information. The resulting network linked datasets can then be easily discovered and employed to address issues such as disaster response, resilience, environmental health, and water resources management.


• Becci Anderson, U.S. Geological Survey, "Stream Network-Based Data Referencing and Search via USGS’s NHI"
As the OMB A-16 Co-Lead for the Water Inland theme, the USGS oversees mapping of the inland waters of the United States, including the National Hydrography Dataset (NHD), the Watershed Boundary Dataset (WBD), and the NHDPlus High Resolution (NHDPlus HR). To support improved sharing and discovery of water-related information through initiatives such as the Internet of Water, the USGS and partners are developing the open and interoperable National Hydrography Infrastructure that uses the NHDPlus HR dataset as a nationwide framework against which to link and discover data in the context of the stream network using enhanced web-based services and tools. This presentation will cover the current status and future direction of the framework, services, tools, and systems of the National Hydrography Infrastructure.

Monitoring and Evaluating Hydrologic Changes in Coastal Estuaries

Moderator: Rajendra Khanal

Presenters:

• Megan Kramer , University of South Florida, "Evaluation of Hydrodynamic Effects of Waterway Restoration on Estuarine Ecosystems in Charlotte Harbor, Florida"
Estuaries are hydrodynamically complex for they are influenced by tidal forces, freshwater flows, salinity variations, and often intricate coastal land morphology. Furthermore, many estuaries are subject to constant anthropogenic stresses due to dense coastal populations, which are expected to be exacerbated by changing climate trends. The 1,800 home residential Manchester Waterway community located in Charlotte Harbor, Southwest Florida, is interested in improving boat access by restoring a previous connection between the local waterway and the harbor, separated by a barrier peninsula. The proposed connections aim to reduce boat traffic and travel time through the waterway, which would result in environmental benefits such as reduced fuel consumption, erosion, and air pollution. Additional benefits include improved emergency response time and more recreational opportunities. This study evaluates how connectivity and coastal land morphology influence flow patterns by modeling the effects of the proposed restoration project on water movement between Manchester Waterway and Charlotte Harbor. An unstructured grid, 3D model was developed utilizing Delft3D Flexible Mesh to simulate estuary hydrodynamics under three different connectivity scenarios for both normal and extreme weather conditions. Elevation and model boundary data for Charlotte Harbor were gathered from NOAA and USGS databases. High resolution bathymetry and water level data were collected during field visits within the Manchester Waterway for model calibration and validation using sonar and installed level logger devices, respectively. Results will be compared to current flow patterns to analyze changes in water levels, flow speed and direction, and salinity. As this project is a community driven effort, research findings are regularly communicated with the Manchester community. Model simulation results will aid local decision making for the future of the waterway, and also improve understanding of the major influencing forces in intricate estuarine environments and how these ecosystems may respond to human activities and climate projections.


• Alec Colarusso , University of South Florida, "Sea Level Rise, OSTDS Vulnerability Zones and Potential for Failure, and Environmental Impacts: A Coastal Watershed-Based Study"
There are an estimated 2.7 million Onsite Sewage Treatment and Disposal Systems (OSTDS) located within Florida and serve as potential sources of contamination. The intersection of OSTDS density and vulnerability (i.e., potential for failure) due to current and futuristic stressors that impact the groundwater table such as sea-level rise (SLR), Saltwater Intrusion (SWI), and flooding brought on by climate change have the potential to discharge harmful levels of nutrient and fecal contamination directly to groundwater and indirectly to surface waters and consequently to coastal waters leading to adverse environmental and human health impacts. The identification of vulnerability zones under current and future stressors will help us allocate limited resources for monitoring in critical areas to develop policies related to the prevention of OSTDS failure. Previous studies have shown that spatial co-occurrence of high density of OSTDS coincided with higher concentrations of nutrients and enteric pathogens as well as higher rates of beach closures. This study will extend previous research by developing two sets of vulnerability maps for current and futuristic stressors that lead to the failure of OSTDS using geospatially integrated approaches. This project will also examine nitrate loading, a common source of contaminants from OSTDS for subsets of the study area (highly vulnerable areas) using ArcNLET to demonstrate nitrate transport pathways and analyze spatial occurrence of OSTDS. The study area is comprised of 14 HUC8 watersheds where SWI, a proxy for SLR, has been recorded. Data were obtained from various state and federal agencies where current analysis timeframe includes 2000-2020 and futuristic SLR (2040-2100). Key datasets are: watershed-level hydrological data including groundwater inundation to SLR, coastal and inland flooding(C/IF), storm surge potential, Harmful Algal Blooms (HAB), Nitrate, enteric pathogens, impacted waters, and beach closures, where available. ArcNLET results will be validated using Nitrate, data and vulnerability maps will be validated using hindcasting methods. Preliminary results show spatial co-occurrence of high nitrate and pathogens concentration above critical limits (200+ CFU, fecal coliform; 35+ CFU, Enterococci; and 10 mg/L, nitrates) in coastal waters adjacent to area characterized by a high density of OSTDS that are impacted by current SLR and SWI.


• Nathaniel Morton, Andrew Brenner, and Chris Anastasiou, NV5 Geospatial powered by Quantum Spatial, "A Comparison of the Southwest Florida Water Management District (SWFWMD) Manual Mapping and the Semi-Automated Mapping of Seagrass Habitats for Florida’s Suncoast"
Seagrass habitats are a valuable tool for scientists as they are an important barometer of water quality within Florida’s estuaries. They require relatively clean water to flourish, thus they are sensitive to changes in water clarity and quality. Every two years, maps are produced from aerial photographs and verified for accuracy by conducting field surveys. The results are used to track trends in seagrass and to evaluate ongoing water quality improvements. SWFWMD contracted NV5 Geospatial (Quantum Spatial) (NV5G) to create two mapping products in support of their biennial seagrass mapping updates for the Florida Suncoast region which includes Clearwater Harbor/St. Joseph’s Sound, Tampa Bay, Sarasota Bay, Lemon Bay, and Charlotte Harbor estuaries. New color imagery was acquired for this area at a 1-foot pixel resolution. All photographic signatures within the benthic environment were classified utilizing the Florida Land Use Land Cover Classification System (FLUCCS) schema. NV5G created a manual photo-interpreted seagrass map for the entire Suncoast region utilizing more traditional methods. Mapping was completed in an Esri ArcGIS environment comparing the previous 2016 Suncoast seagrass map to imagery acquired in Winter of 2018. Field work comprised of an accuracy assessment completed in during acquisition, and ground truthing which was completed during the summer of 2018. The accuracy assessment points were generated and provided by the District. Ground truthing points were generated by NV5G, and field work was performed by a field team, including NV5G environmental scientists, to lend credibility to photographic signatures identified in the imagery. Each bay segment was required to meet an accuracy of 90% when compared to an independent accuracy assessment. NV5G also created a semi-automated pilot seagrass map based on a prototype classification model for the Tampa Bay area. This pilot was created by using a classification model in eCognition to draw automatic line segments based on imagery signatures. A manual clean-up and QC process was completed in an Esri ArcGIS environment to ensure proper topology and attribution across all bay segments. This pilot map was compared to the manual photo-interpreted map to assess the viability of a more mathematical approach to seagrass mapping.

Explorations in Multi-faceted Aspects of Groundwater

Moderator: Chin Man Mok

Presenters:

• Andy O'Reilly, USDA Agricultural Research Service, "Managed Aquifer Recharge for Sustainable Groundwater-irrigated Agroecosystems: Objectives, Construction, and Preliminary Performance of a Pilot Facility in the Delta Region of Mississippi"
In the Delta region of Mississippi, groundwater-level declines up to 1 foot (ft) per year in the Mississippi River Valley alluvial aquifer (MRVAA) indicate that groundwater-use practices are unsustainable. Managed aquifer recharge (MAR) is a potential technology to mitigate groundwater depletion, supporting irrigated agriculture as well as sustaining natural ecosystems. In partnership with local stakeholders, the USDA Agricultural Research Service is conducting a pilot MAR project combining riverbank filtration and aquifer storage (RBFAS) to capture water from the Tallahatchie River for direct injection into the MRVAA. The RBFAS system consists of one extraction well 150 ft from the river, a 1.8-mile pipeline to transfer water to an area of greater groundwater depletion, and two injection wells, with a design capacity of 1,500 gallons per minute (gpm). Operation began in April 2021 with an injection rate of approximately 730 gpm for each well. Data collection at 17 monitor wells and the extraction and injection wells include continuous groundwater level and temperature and monthly water samples (major ions, metals, and nutrients). Pre-operation groundwater levels show frequent drawdown events contributing to a 1–4 ft decrease in water level during the summer 2020 growing season; over the fall–spring fallow season water levels recovered 1–3 ft, with generally lesser recovery in the vicinity of the river possibly due to lower surface-water levels compared to the preceding year. Hydraulic connection between the river and MRVAA is suggested by seasonal variations in pre-operation groundwater temperature, specific conductance, and pH. Ambient groundwater prior to operation is less mineralized at the extraction site than the injection site and varies with depth possibly related to variations in lithology. After 30 days of operation 190 acre-feet of water have been injected, resulting in a groundwater mound of 6.0 ft near the injection wells and a drawdown of 4.3 ft near the extraction well. At radial distances of 1,140 ft from the injection and extraction wells, water-level changes were +2.3 and –1.9 ft, respectively. Current plans are to maintain operation of the RBFAS system, collect data for nine months, and assess the environmental and hydrological sustainability of the technology.


• Sandra Fox, Qing Sun, Wei Jin, and Fatih Gordu, St Johns River Water Management District, "Springshed Delineation Using Arc Hydro"
The St Johns River Water Management District (SJRWMD) establishes minimum flows and levels (MFLs) for lakes, river segments, streams, and springs as part of fulfilling its mission and statutory responsibilities. MFLs define the limits at which further water withdrawals would be significantly harmful to the water resources or ecology of an area. To evaluate the impact of groundwater withdrawals on spring flows, springsheds, defined as groundwater contribution areas, have been traditionally delineated using MODFLOW groundwater flow models and particle-tracking program MODPATH. To support and refine the springshed delineations, geospatial analysis tools have been explored. The Arc Hydro Groundwater flow direction generator was previously considered, which produced useful results but was found to be difficult to reproduce and time consuming as it involved “heads up” digitizing from flow vectors. The Arc Hydro DEM Manipulation tools (Terrain Preprocessing) in the Arc Hydro Pro Toolbox were later employed for further exploration of potential use of geospatial tools for springshed delineation. Theoretically, geoprocessing treats a raster potentiometric surface in the same manner as a digital elevation model of the land surface; flow direction follows from places of high to low “elevation” whether it is a water or land surface; boundaries representing flow divergence (drainage areas or “springsheds”) are created. Working with a set of 65 potentiometric surfaces of Upper Floridan Aquifer generated from 1976 through 2010, a series of Model Builder (MB) functions were created to delineate the springsheds for six springs in the SJRWMD. In the first MB function, an iterator runs the set of 65 potentiometric surface rasters through two Arc Hydro functions (“Sink Prescreening” and “Sink Evaluation”) generating “SinkDAs” (sink drainage areas) for each entire surface. The second MB function selects only the SinkDAs that are coincident with the selected spring. Additional MB functions convert these polygons to raster format for ease of accounting and determining the area of greatest overlap to be defined as the geospatially determined springshed. These “springsheds” are compared to springsheds generated by MODFLOW and MODPATH. The product of both efforts is to provide SJRWMD with defined springsheds for the six springs."


• Chin Man Mok and Barbara A. Carrera, GSI Environmental Inc. and Iason Papaioannou, Technical University of Munich, "Tomographic Delineation of Subsurface Heterogeneity Using Groundwater Extraction/Injection Operational and Monitoring Data"
The delineation of hydraulic conductivity (K) heterogeneity is essential to support effective remediation of environmental sites and sustainability management of groundwater basins. However, K characterization by conventional methods is a difficult and expensive task at sites with complex hydrogeology. Inadequate K characterization has resulted in poor remediation performance at many legacy environmental sites and excessive potentiometric head decline at many over-drafted wellfields. Recently, a technique based on sequential pumping tests and stochastic hydraulic tomography (HT) inversion using successive linearization estimator (SLE) has been demonstrated to be effective for delineating K heterogeneity The HT technique was initially developed to treat the K-distribution in a groundwater model as a correlated random field and to invert the model stochastically using the hydraulic head response data from individual aquifer pumping/injection tests. Although many environmental sites with pump-and-treat systems and water suppliers with production wellfields have collected an abundant amount of operational and monitoring data, sequential pumping tests by temporarily shutting down individual wells might not have been performed. Performing such tests might not be possible due to operational constraints. Even if they have been performed, the duration of operational changes might have been too short. The monitoring data during a temporary operational change always contain the complex signature of previous operations prior to the change. Although all historical data can be theoretically utilized for HT inversion, the computational effort needed is practically infeasible. We will present a computationally efficient approach based on a combination of Transfer Function Noise (TFN) analysis and Hydraulic Tomography (HT) analysis to estimate the spatial K-distribution and the associated uncertainty using abundant extraction/injection operational and monitoring data. We will use the operation and monitoring data collected at an environmental site in Arizona as an example. The TFN technique can be applied to estimate the hydraulic head response to constant-rate pumping/injection at each relevant well through convolution integration. Such step-response functions are equivalent to the data collected from individual aquifer pumping/injection test without carrying any long-duration pumping/injection operations signals and can be utilized directly in HT analysis. We will present an efficient approach to simplify the HT computations by incorporating principal component analysis (PCA) to reduce the numbers of parameters and the number of calibration targets. This method allows for the removal of both parameter and calibration target dependencies without losing significant information. In addition, we will present a Markov Chain Monte Carlo (MCMC) approach for HT inversion. This approach can be easily adopted to use any forward simulation models.


• Jian-Dao Li , National Yunlin University of Science and Technology, "Explore the Influence of Different Boundary Condition Assumptions on Estimating Hydraulic Properties"
In recent years, hydraulic tomography (HT) is a popular method for delineating the spatial distributions of hydraulic properties in the groundwater aquifer. When estimating the spatial distributions of hydraulic properties of aquifers, the uncertainty of many conditions (such as boundary conditions) will cause the verification results to be non-unique (Mao et al., 2013; Yeh et al., 2015). Daranond et al. (2020) and Liu et al. (2020) successfully used horizontal flow numerical experiments to explore how to estimate unknown boundary conditions. However, this method for estimating boundary conditions has not been corroborated by on-site or sandbox pumping test data and vertical flow. The advantage of the sandbox pumping test compared to the on-site pumping test is that the boundary conditions are known and controllable. Therefore, this study will be discussed the method through vertical flow numerical experiments and sandbox pumping tests. We do the pumping test in the sandbox and numerical experiments whose sides use three kinds of boundary conditions (constant head fully distributed and two kinds constant head and impermeable staggered distribution) and estimate the distributions of hydraulic properties through HT. Based on the distribution of extreme hydraulic properties, determine the distribution of boundary conditions, and compare with actual ones.

Investigations into Harmful Algal Blooms in Florida

Moderator: Qiong Zhang

Presenters:

• Qiong Zhang, University of South Florida, "Temporal and Spatial Optimization of Existing and Emerging Nutrient Management Technologies and Practices for Control of Harmful Algal Blooms in Lake Okeechobee"
This presentation will introduce a project funded by the U.S. Environmental Protection Agency that focuses on the optimization of watershed-based nutrient management technologies and practices for control of harmful algal blooms (HABs). The research specifically addresses excess nutrient loadings to Lake Okeechobee (Florida) from its large watershed that stimulate the growth of HABs. Nutrients and HABs in L. Okeechobee are subsequently transported to both the southern Everglades and the Atlantic and Gulf coastal zones. HABs due to excess nutrient loads in L. Okeechobee affect both freshwater and coastal ecosystems and are representative of many freshwater bodies around the country with wetland loss and stream channelization, a legacy of agricultural pollution, and more recent urban sprawl. We will provide an overview of four planned tasks in the project: Task 1- develop a holistic assessment framework and evaluate the effectiveness and sustainability of nutrient management technologies/practices; Task 2- identify the appropriate approach to scale up selected emerging technologies and evaluate their performance; Task 3- develop a modeling platform to integrate watershed hydrology and lake ecology to predict temporal algae production corresponding to nutrient loading; and Task 4- create a decision support framework to optimize implementation of the most promising management practices and technologies. The approaches in each task and their integration will be explained and demonstrated with ongoing research. In addition, we will discuss how stakeholder engagement and feedback guide the progress of the project. The project results and outputs will facilitate a holistic assessment of nutrient management technologies/practices and an optimized implementation of best management practices for effective HAB control.


• Jiayi Hua and Rachael Cooper, University of South Florida, "Sustainability Assessment Framework for Nutrient Reduction in the Lake Okeechobee Watershed"
Lake Okeechobee, the ‘liquid heart’ of South Florida, and a part of the Northern Everglades has experienced several severe harmful algal blooms (HABs) caused by excess nutrients. Multiple sources of nutrients exist within the watershed with varying strategies for nutrient reduction and treatment to control HABs creating complex conditions for proposing effective treatment in a watershed larger than 4,500 square miles. No existing framework considers both technologies and Best Management Practices (BMPs) from all point source and non-point sources for nutrient control. Therefore, a novel comprehensive sustainability assessment framework was developed to evaluate both technologies and BMPs from all sustainability dimensions and nutrient sources. The framework was developed as Task 1 of a project funded by the U.S. Environmental Protection Agency focused on the optimization of nutrient management technologies and practices within the Lake Okeechobee Watershed with three additional project tasks, which include scaling-up emerging treatment technologies (Task 2), a watershed and water quality model of the lake (Task 3), and an optimization model for selecting nutrient load reduction technologies and practices within the watershed (Task 4). Indicators for the framework were chosen from related frameworks or designed as composite indicators from nutrient management reports. Nutrient sources within the watershed include municipal and industrial wastewater, urban and agricultural runoff, and onsite sewage treatment and disposal systems. Existing technologies and BMPs in the watershed for each nutrient source were evaluated using the framework and scores will be compared. The designed indicators and application of framework was also compared with a previous technology evaluation within the Northern Everglades for the same technologies. The results of the holistic framework were used as a comprehensive evaluation for the sustainability of technologies and BMPs applicable nutrient sources within the watershed. The evaluations will then be used to pre-processing the input to or post-processing the output from the optimization model developed in Task 4, which will select applicable technologies within the watershed given constraints of cost and nutrient load reduction. Together the framework and optimization model can simplify the decision-making process for proposing effective nutrient treatment at the watershed scale to reduce HABs within Lake Okeechobee.


• Vahid Mahmoodian , University of South Florida, A Novel Optimization Model for Controlling Harmful Algal Blooms in Lake Okeechobee"
We study how nutrient contamination can be minimized in Lake Okeechobee, one of the largest natural freshwater lake in the US. The lake and all its nine surrounding watersheds in the central Florida are suffering from the overgrowth of harmful algal blooms due to the nutrient contamination. The out-washed fertilizers or other industrial and residential effluent are the main sources of nutrient contamination. In the existing body of literature, there exist two types of remedies that are often suggested to reduce nutrient contamination. The first one which is a preventive approach includes some rules or policies, called Best Management Practices (BMPs), that can be enforced in certain land uses to monitor, control, and decrease the amount of nutrient loading. The second one which is a curative approach includes some Water Treatment Technologies (WTTs) that need to be implemented on rivers or reaches to refine nutrients from water. In this study, we consider both of these approaches at the same time. We develop a generic mathematical optimization model for minimizing the nutrient contamination in lake Okeechobee by determining the best combination of BMPs and WTTs as well as their size and the optimal locations to implement them. We show how the model can be extended to include the uncertainty available in the performance of the BMPs and WTTs. Our numerical analysis on some Lake Okeechobee watersheds show that the model can effectively minimize the nutrient contamination in the lake.