Dr. Laura Christianson, University of Illinois
Improving denitrifying woodchip bioreactor design and management through denitrification potential testing
Denitrifying woodchip bioreactors promote biological removal of nitrate to prevent negative environmental consequences of nitrate loading to downstream waters. Bioreactor media should promote complete denitrification while maintaining high rates favorable for nitrate removal. Considering woodchip type, oak had the highest denitrification potential, which also corresponded to the most nitrate removal in lab
studies. While the oak type had a higher proportion as N 2 O, the overall proportion was low for all submerged woodchips (<14%), suggesting that woodchips generally have high potential for complete denitrification. Therefore, woodchip type could be an additional consideration for bioreactor design and construction, but this needs to be contextualized within practical factors such as woodchip availability and cost. In addition, field conditions that are known to influence performance and N 2 O proportions should be monitored over time to ensure bioreactors are reaching optimal performance. Without exposure to drainage water, fresh woodchips were capable of denitrification, albeit at a much
lower rate than active or spent woodchips harvested from an operational bioreactor in the field. This demonstrated that denitrifying organisms are present in woodchip media prior to installation in bioreactors. Drainage water denitrification was not detectable by these methods, but it is still possible that microorganisms may also be sourced from tile water. Additional experiments are needed to further explore the source of denitrifying organisms in bioreactors.
1. Compare denitrification potential and N2O production potential between woodchip types and soil types.
2. Compare denitrification potential between tile drainage water, bioreactor-sourced woodchips, and fresh woodchips.
Dr. Brian Deal, University of Illinois
A Coupled Urban Spatial Simulation and Stormwater Runoff Models and its Implications for Physical Design: The Case of Chicago
The goal of this proposed research is to develop a framework that bridges the gap between scientific knowledge (hydrologic engineering) that quantitatively simulates stormwater runoff and the design practices that visually implicate the built environment. We claim that these gaps should be filled by cross-disciplinary approaches in a bid to guide urban systems toward more resilient outcomes. To do this, we will utilize an existing coupled model system that closely couples the Gridded Surface Subsurface Hydrologic Analysis (GSSHA) with the Land-use Evaluation and Impact Assessment Model (LEAM). The modeling system has been developed by the LEAM laboratory to spatially and quantifiably forecast runoff in Chicago in response to various growth scenarios. Second, we will examine the relationship between runoff
and design factors to identify the salient factors of influence that are most applicable to landscape design practices. Specifically, the combination of a boosted regression tree and piecewise linear regression will be used to identify the rank importance of design factors and establish their thresholds. Third, we will test the framework in practice by infusing the modeling system in a cross-disciplinary design studio environment by infusing the spatial simulation results and statistical relationship outcomes with the design process. The proposed research will promote cross-disciplinary research in areas ranging from hydrologic/land-use modeling to urban/landscape design. Ultimately, it will lead the design discipline toward analytic approaches for resilience issues. Lastly, we expect the results of our proposed research to benefit the wellbeing of communities in Illinois by potentially decreasing runoff vulnerability.
Dr. Kaiyu Guan, Yi Yang, University of Illinois
Towards better agricultural drought assessment and irrigation management: improving the simulation and understanding of plant water stress for crops in Noah-MP land surface model
Two new methods for modeling plant water stress will be implemented into the Noah-MP land surface model to improve the simulation of plant water stress for crops. The new and existing methods will be evaluated and compared within the same modeling framework to improve our mechanistic understanding of plant water stress and the modeling of it. The revised Noah-MP models will also be useful for assessing crops’ response to dry weather conditions and guiding irrigation management, and thus have practical uses in agricultural production in Illinois and the U.S. Corn Belt.
Statement of Expected Benefits:
Accurately modeling plant water stress is key to evaluation of drought impacts on agro-ecosystem productivity and irrigation management. Plant water stress can be triggered by insufficient soil water content (SWC; water supply) and high atmospheric vapor pressure deficit (VPD; water demand), either independently or collectively (Katul et al., 2012). For crops, plant water stress is one of the major hazards in dry weather conditions, especially when extreme weather is becoming more and more frequent under climate change (Rosenzweig et al., 2001).
Statement of Expected Results:
We plan to implement and test a plant hydraulic model and a water supply-demand based model in the Noah-MP LSM and compare the results with the existing Ball-Berry stomatal conductance scheme with an empirical soil water stress function. We hypothesize that both newly implemented models can improve the performance of soil water stress representation and vegetation water use dynamics. We further expect that the water supply-demand based approach would be advantageous when fewer plant hydraulic measurements are available because its parsimonious representation could be more easily constrained.
The objective of this study is threefold: (1) implement the two new methods in Noah-MP; (2) compare the results of the two new methods and existing method in Noah-MP; (3) compare the performance of the two new methods under different scenarios and evaluate their pros and cons that may help us understand
their applicability in different situations.
Dr. Eric W. Peterson, Illinois State University
Utilizing a tracer test to calculating the transport and fate of nitrate within a saturated buffer zone
Agriculture is acknowledged as a leading cause of surface water pollution [1, 2], serving as the principal source of nitrogen (N), primarily nitrate (NO3), to aquatic environments [3-6]. Hypoxia, eutrophication, and biodiversity changes within surface waters, specifically the Gulf of Mexico, are attributed to excess NO3 loading [7-10]. On an annual basis in the US Midwest, an estimated 1 million metric tons of N is leached from the agricultural fields into waters of the Mississippi River . Since 1950, the NO3 load discharged into the Gulf of Mexico has tripled [9, 12]. Illinois has been identified as the second leading contributor of
NO3, with Illinoisan agricultural activity contributing 19% of the NO3 load delivered to the Mississippi River [13-16].
1) Identify the flowpath of the waters traveling from the diversion tiles to the stream.
2) Measure the travel time for the waters along the flowpath to the stream, i.e. what is the residence time of the waters in the SBZ? Preliminary calculations using Darcy’s Law suggest a travel time from the eastern diversion tile to well 6 of approximately 51 days.
3) Calculate the amount of dilution using a mixing model.
A tracer test will be conducted to address the question and objectives. Sodium bromide (NaBr) will be introduced into the tile-diversion box. NaBr was chosen because the measured background concentrations of Br- have consistently been below 0.5 mg/L. Prior to the initiation of the test and once every two weeks over 22 weeks, waters from 20 wells (not 14 or 15), the diversion box, and the stream will be collected and analyzed.
Agricultural runoff diversion into SBZ may be a potential best management practice (BMP) to reduce NO3 in tile-drained waters. Outcomes from this project will further address the source of reduction, dilution or removal (denitrification or assimilation). The project will be considered successful if (1) travel times for the waters from the diversion tile to the wells are quantified, (2) a graduate student is trained in field and laboratory techniques, (3) a MS thesis has been completed, (4) presentations by students at an Illinois Water conference, an Illinois Groundwater Association meeting, and the annual Geological Society of America meeting, and a peer-reviewed publication have been completed. These results represent baseline data necessary to support all future research activities and develop appropriate BMPs for NO3-N applications.
Ashlynn Stillwell, Joseph Bongungu, University of Illinois
Estimating Residential Hot Water Use with Smart Electricity Data
In this project, we aim to estimate residential hot water use from smart electricity data for areas in greater Chicago. We estimate electricity for water heating, as a measure of hot water consumption, using meter-level data for single-family residential homes (with electric space heat) at 30-minute resolution.
We hypothesize that “smart” electricity meter data can provide an estimate of hot water consumption, via electricity for water heating.
Our findings reveal that disaggregation of electricity meter data can provide an estimate of water heating; however, those estimates have significant uncertainty due to the temporal resolution of the electricity data. These findings
1) provide estimates (albeit overestimation) of hot water consumption in single-family residential homes;
2) demonstrate spatial variability in water heating and energy load;
3) emphasize the need for finer temporal resolution electricity data for further study.
We use non-intrusive load monitoring (NILM) to reveal the electricity signal for estimated water heating “on” events. Given the uncertainty in NILM techniques and the lack of ground-truthed water heater data, we conducted the disaggregation over a selected 2-week window with daily load patterns and weather conditions reflecting a likely lack of heating or air conditioning usage.
The results of our work are currently in preparation for publication in a journal manuscript and Joseph Bongungu’s M.S. thesis. Both publications will be submitted in May/June 2020. Results indicate that water heating in the analyzed single-family residential homes accounted for 8-17% of total electricity consumption, representing an average of 40-60 gallons of hot water consumption per day.
Dr. Xiao Su, Stephen Cotty, University of Illinois
Electrochemically-mediated adsorption systems for selective nitrate recovery: agriculture and the water-energy nexus
We developed a hybrid structure which consists of an electrically-conductive support framework (carbon black and carbon nanotubes (CNTs)) with the coating of redox-responsive polymeric films (polyvinylferrocene (PVF), poly-TEMPO-methacrylate (PTMA), polyaniline (PANI), Poly(3-hexylthiophene-2,5-diyl) (P3HT). In our preliminary result using density-functional theory (DFT), it was shown that nitrate binds strongly to oxidized ferrocene group. In our lab-scale preliminary tests, PVF-CNT electrode showed fast adsorption kinetics (reaching equilibrium within 1 h), and the highest uptake up to 200 mg/g. This model polymer allowed electrochemically-controlled capture and release of nitrate, like on/off switches, exhibiting >95 % regeneration efficiencies and thus demonstrating fully reversible, electrochemically
modulated nature of our process. In addition, we found that PANI revealed the higher adsorption uptake than any other materials tested (45 mg/g for PANI and 10 mg/g PVF at 1 mM nitrate). We hypothesize that hydrogen bonding with protonated amine group (-NH 2 + ) site is responsible for selective separation. Redox-mediated operation allows adsorption and desorption via simple electrical swings with minimal pH, temperature or other changes in solution conditions, and combines the inherent advantages of electrochemical methods, including high capacity, fast kinetics and modularity, without the selectivity limitations present in traditional capacitive deionization. Thus, this energetically-efficient, point-of-source system for nitrate recovery will be expected to strongly increase community resilience to nutrient
problems, and provide a techno-economic motivation to agricultural stakeholders to employ these technologies on the long-term. Continuation of the efforts are being pursued by PI Su and co-PI Cotty.
Dr. Lei Zhao, University of Illinois
Modeling the Effects of Green Stormwater Infrastructure Implementation on Urban Hydrology and Urban Heat Islands in Illinois
As urban infrastructure continues to age, the worldwide urban population continues to rise and climate change effects are being increasingly felt in urban environments. Coupled together, these factors have placed significant stress on the urban landscape. Green stormwater infrastructure (GSI) implementation has been identified as a possible tactic to combat these effects of urbanization and climate change and to help make cities more resilient and “livable.” Using the Community Earth System Model (CESM), we aim to quantify the hydrologic impact and urban heat mitigation co-benefits of GSI implementation in Illinois cities over a 30-year time period. We will simulate ground-based GSI technology, bridging microscale vegetation models and macroscale climate models to represent resilience effects of widespread green space in urban areas.
Statement of Critical Problem:
Urban flooding has become a prominent issue for many cities, arising from a combination of altered precipitation patterns, urban growth, development in floodplains, and increases in impervious surfaces. Climate models consistently project that frequency, severity, and duration of these extremes will increase markedly over this century under climate change. There is a pressing need to advance fundamental understanding of how climate adaptation strategies deliver hydroclimatic benefits
for cities under climate change coupled with urban development
Statement of Expected Results and Benefits:
Through this project, we aim to model the widespread implementation of GSI in cities
throughout Illinois using the Community Earth System Model (CESM) 18. We will focus on ground-based vegetated GSI features such as rain gardens and bioswales, which are designed to control, reduce, treat, and infiltrate runoff19. Our expected results include:
1) quantification of the effectiveness of GSI in reducing urban temperature and runoff over different cities in Illinois,
2) analysis of the impacts of GSI on urban surface energy and water budget.
3) understanding of impacts of GSI on urban hydroclimatology.
Based on these analyses and results, we will report our findings in peer-reviewed journals and educational videos, with policy and design recommendations for GSI and how it contributes to the city’s “livability”.
We propose to model green stormwater infrastructure (GSI) implementation in urban areas of Illinois and analyze the effects on urban hydroclimatology, flooding mitigation potential, and urban heat mitigation. The specific objectives include:
1. Model urban hydroclimatology and runoff for cities of different sizes in Illinois using the default parameters in CESM as a baseline (control for future comparison).
2. Determine the representation and parameterization of widespread GSI in CESM based on calibrated observations from microscale rain gardens.
3. Quantify and visualize the model outputs regarding urban flooding mitigation and heat mitigation benefits.
Linduo Zhao, Nandakishore Rajagopalan
Low cost mycelial stabilization of coal combustion products to reduce As, and Se contamination of groundwater
This proposal seeks to stabilize coal combustion products through encapsulation in a fungal matrix and thereby prevent groundwater contamination by arsenic and selenium. While fungi have been effective in treating various contaminants, its application to mitigate pollution from coal combustion products is limited. Our preliminary results show that mycelial encapsulation is very effective in reducing As and Se leaching from fly ash. This 1-year proposal seeks to further (a) define the culture conditions for effective mycelial encapsulation of coal combustion products and (b) assess the arsenic and selenium leachability from mycelia encapsulated coal combustion products under realistic groundwater conditions.
We hypothesize that fungal mycelium can be utilized to prevent groundwater
contamination by arsenic and selenium released from coal combustion products.
Task 1: Identify and quantify the key parameters that affect fungal mycelium growth in CCP matrix and their effects in reducing metal leaching potential from CCP.
Task 2: Evaluate the effectiveness of utilizing mycelium-encapsulated CCP matrix to prevent metal contamination in simulated groundwater flow-through or circulation systems.
This project will be conducted in the biogeochemical lab at Illinois Sustainable Technology Center. It will include significant participation of two undergraduate students from Natural Resources and Environmental Science Department: Madalyn Liberman and Sabine Miller. They will be trained in mycelium culture, column experiments, sample collection/analysis, and data reporting. By doing so, the students will obtain laboratory skills and experience in designing and conducting environmental studies. The results, if successful, will be adapted and modified for field level application through engagement of colleagues from PRI with expertise in ground water modeling and geotechnical engineering. It is expected that the results, if successful, will result in an IP disclosure to the Office of Technology Management, UIUC and also form the basis of a proposal to USDOE in 2020.