WRRC Section 104B Program Funded Projects

The Water Resources Research Center (WRRC) provides grants for research proposals under the Water Resources Research Act, Section 104B. Funded by the U.S. Geological Survey, Section 104B provides support for small research projects on water-related issues of importance to the state and region. The WRRC generally distributes about $50,000 to fund research projects each year. Faculty members at the three Arizona state universities may submit proposals.

FY 2007

Riparian Vegetation Response to Cessation of Groundwater Pumping, Lower San Pedro River, Arizona, $11,990, Julie Stromberg, Arizona State University.

Hundreds of millions of dollars are being spent on the restoration of riparian ecosystems throughout the Southwest, often without sufficient scientific background to inform the efforts and ensure success. A novel restoration approach has been pioneered along the lower San Pedro River by the Nature Conservancy of Arizona and other collaborating groups. The lower San Pedro River Basin constitutes an important conservation landscape in southeastern Arizona, but, on some reaches, groundwater and surface water have declined below threshold levels needed to sustain cottonwood-willow forests and emergent wetlands. In some areas, tamarisk shrublands now dominate the floodplain, and the stream channels are wide and dry. The restoration approach involved purchase of farms that pumped large quantities of alluvial groundwater for crop irrigation, and subsequent reduction of pumping rates to negligible levels. The assumption is that the biotic components of the riparian ecosystems will establish on their own accord, following restoration of the hydrologic regime, thereby obviating the need for restoration plantings. There is a need to document the results of this hydrologic restoration strategy to assess its effectiveness on the San Pedro River as well as its applicability to other settings. In 2002 and 2003, the PI initiated baseline monitoring at seven restoration research sites and five reference sites on the Lower San Pedro. The PI is using research funds to allow for another year of data collection and for data analysis and synthesis. Data will be collected on metrics that should change rapidly in response to hydrologic restoration (herbaceous vegetation composition and diversity along the low-flow channel; annual growth increments of Fremont cottonwood and Goodding willow trees; woody tree seedling densities) and those that will change over a longer time span (woody vegetation density, composition, and age structure; floodplain patch structure; stream geomorphology). Results will provide managers with feedback about the effectiveness and time-span of this restoration approach. Another important benefit relates to informing approaches to the management of tamarisk, considered by some to be a problematic species. The PI expects that the hydrologic changes at the Lower San Pedro restoration sites will drive shifts in woody riparian plant composition from tamarisk to cottonwood/willow; if so, this study will provide a demonstration of an alternate approach to traditional invasive species management.

Compound Specific Isotope Determination of Biodegradative Activity in a Chlorinated Solvent Contaminated Aquifer System, $10,000, Mark Brusseau, University of Arizona.

The sustainability of potable water supplies is a critical issue in Arizona, given the recent and ongoing population increase, economic expansion, and arid climate. A major component of water-resources sustainability is the contamination of vital groundwater supplies by hazardous chemicals. In Arizona, chlorinated solvents, including tetrachloroethene (PCE), trichloroethene (TCE), dichloroethene (DCE), and vinyl chloride (VC), are the primary contaminant at 43 of 48 State and Federal Superfund sites. In aggregate, these sites comprise billions of liters of contaminated groundwater. Accordingly, these chlorinated-solvent contaminated sites pose a significant and long-term risk to the sustainability of potable groundwater in Arizona. Remediation of polluted soil and groundwater at chlorinated-solvent contaminated sites is therefore of immediate importance in protecting groundwater resources in the state of Arizona. Recently, monitored natural attenuation (MNA) has garnered increasing interest as a low cost, effective solution for remediation of contaminated groundwater. The successful application of MNA has the potential to save millions of dollars in remediation costs, as well as protecting the quality of critical groundwater resources. The goal of this project is to provide a simple and broadly applicable method to assess the feasibility of using MNA at chlorinated-solvent contaminated sites in Arizona. The availability of such a method would greatly enhance the ability to quickly and effectively evaluate sites, thereby providing valuable information for site owners and regulators. One potential low-cost, rapid method for directly identifying the presence of biological natural attenuation processes is Compound Specific Isotope (CSI) analysis. This method takes advantage of the natural fractionation of carbon isotopes during biological transformation. The specific objective of this project is the development of CSI analysis methods that will permit rapid and accurate screening of the suitability of Arizona sites for MNA.

Sources of Nitrate in Groundwaters of the Tucson Basin, $9,121, Thomas Meixner, University of Arizona.

While it is generally assumed that high nitrate levels in groundwater are associated with human activities (irrigation, fertilizer use, feed lots, septic tanks and municipal sewage), in arid states like Arizona this is not always the case. Often times elevated nitrate in groundwater can be due purely to natural processes, a combination of natural and human processes, or neglected human impacts on the environment (e.g. atmospheric nitrogen deposition). Since understanding the mechanism of contamination is the first step to understanding how to solve any contamination problem, significant efforts have been expended in the past to understand the sources and mechanisms of nitrate contamination in groundwater. This project will utilize two differing flow path transects within the Tucson basin to investigate the sources of nitrate to groundwater in the Tucson basin. The research has three objectives 1) Use geochemical and isotopic techniques to quantify groundwater sources. 2) Quantify nitrate isotopes to connect groundwater nitrate to various nitrate sources and sinks. 3) Develop conceptual model of nitrate sources and processes along the two flowpaths using results of first two objectives and existing nitrate and groundwater geochemical data. To achieve these objectives we will collect water along two flowpath using Tucson Water wells. The first transect will traverse the Tanque Verde and Rillito creek drainages and look at an increase in nitrate along this transect. The second Set of wells will be across the Santa Cruz river in the neighborhood of the Sweetwater recharge facility where there are high nitrate concentrations near the river and lower nitrate concentrations farther from the river. The first transect allows us to focus on the sources of water and nitrate in the groundwater system while the second transect allows us to investigate the relative importance of denitrification or mixing around the sewage recharge facility. Samples from each transect will be analyzed for major geochemical composition and sulfur, water and nitrate isotopes. These suites of geochemical and isotopic analyses should allow us to partition the reasons for nitrate variability in Tucson groundwater between water sources, biogeochemical sinks and mixing.

Geospatial Analysis of Urban Thermal Gradients: Application to Tucson Arizona’s Projected Water Demand, $12,000, Christopher Scott, University of Arizona.

The water budgets of urban and urbanizing areas are hypothetically affected in a significant manner by rising regional temperatures, which have been demonstrated to result from urban heat island effects and broader warming across the Southwest. Both urban and regional warming are projected to increase even further with city growth and climate change. It is therefore important to understand the relation between urban water demand and spatial and temporal temperature trends in urban [-izing] areas. This project proposes to conduct geospatial analysis of Landsat TM thermal infrared data (x, y, t) and DEM (z), thereby generating surfaces of heat source-sink gradients, signatures of the persistence of thermal threshold exceedances, and identifying features or episodes of thermal reset, e.g., [micro-] topographic cooling corridors, vegetation buffers, or precipitation events. For the Tucson Arizona basin, thermal gradients will be mapped over the period 1984 to the present and spatially correlated to urban growth, urban heat island effects, and water supply. Indoor vs. outdoor water use will be estimated from supply data using temporal disaggregation techniques. Results will be assessed with reference to the growth and water demand scenarios in the Tucson Water Plan 2000-2050. The resulting thermal surfaces and persistence datasets are also expected to be of utility to planners, urban landscape ecologists, and the research community. The project will a) produce a manuscript for submission to a peer-reviewed journal, b) result in multiple proposals for continued investigation targeted particularly at EPAs Science to Achieve Results (STAR) and NSF’s Coupled Natural-Human Systems (CNH) programs, and c) support the teams efforts to strengthen the University of Arizona’s capability and expertise in the area of human-environmental feedbacks in the rapidly urbanizing Sonoran Desert Ecoregion.

Modification of Conventional Wastewater Treatment Processes for Estrogen Removal, $11,454, David Quanrud, University of Arizona.

Meeting regional water demands without long-term reliance on groundwater mining will depend on wastewater renovation and reuse. By 2025, it will be necessary to reclaim and reuse approximately 100,000 AFY of wastewater in the Tucson Active Management Area. Acceptable uses and use-dependent treatment requirements remain to be established. That is, growth cannot be sustained without considering water resources of lower water quality. Municipal wastewater is the only resource of that kind that is present in abundance in every high-growth region including Tucson or, if magnified, the Tucson/Phoenix corridor. Observations during the last decade or so related to residual trace organics in conventionally treated wastewater suggest that advanced treatments are requisite to the kinds of reuse applications that are now being considered. Among the myriad trace organic contaminants in wastewater effluent, hormones and hormone mimics may be of greatest concern to human and environmental health. Estrogen and estrogen mimics are among the most relevant sources of concern in waters destined for reuse. Wastewater reclamation and reuse will be a major part of both water supply and wastewater treatment planning. The fate of trace organics during wastewater treatment or, from another perspective, facilities design/operation for control of trace organics should be an important factor in facilities planning. The project is designed to provide data in that critical area. The project is a full-scale investigation of wastewater treatment processes that are likely to reduce significantly the activities of estrogenic and androgenic compounds in wastewater. The processes of interest are (i) membrane biological treatment and (ii) activated sludge treatment.

FY 2006

Student Training, Research, and Participation in Water Harvesting Design and Implementation. $11,624. J. Riley, University of Arizona

This project will develop the means to apply water harvesting techniques at the University of Arizona and educate university students about water harvesting while addressing significant surface water flow concerns on the university campus. The project will work initially with the Surface Water Working Group in solving a flooding problem near the McKale Memorial Center sports complex by incorporating appropriate water harvesting interventions. Students will work closely with principal investigators, consultants, and university staff to study existing problems and design and implement innovative water harvesting solutions, possibly including infiltration basins, swale and berm contouring, mulches, walk way redesign, and native plant landscaping, .

Perfluorinated Chemicals in Municipal Wastewater Treatment Plants in Arizona. $11995. R. Sierra, University of Arizona.

There is presently no data on the occurrence of PFCs in wastewater treatment plants in Arizona, yet PFCs are extensively used in the growing semiconductor industry sector in the State and in a wide variety of other industrial, commercial and consumer applications. This study will develop novel methods (F-NMR, HPLC/MS/MS) to detect and quantify PFCs in municipal wastewater and in sewage sludge, and then apply these methods to conduct a preliminary evaluation of PFCs in selected municipal wastewater treatment plants in Arizona. Partitioning of PFCs into biosolids will also be investigated under well-defined laboratory conditions.

An Investigation in the Upper Santa Cruz River 2005 Riparian Vegetation Die-off. $11,940. B. Orr, University of Arizona.

Since approximately March of 2005, a significant fraction of the riparian trees and upland mesquite bosques along a 10-mile stretch of the Upper Santa Cruz River have been dying for unknown reasons. The die-off is an indication that the balance of the ecosystem has recently shifted, and the future direction of water management will need to incorporate this shift into decision-making processes. As a preliminary step in this direction, this project will integrate geospatial and temporal analysis of historical photography and satellite imagery, basic water quality analysis and tree pathology testing to understand the historical context and potential causal factors which may provide insight into this sudden mortality.

Advanced Biotechnology for Recycling Dairy Wastewater. $12,600. Q. Hu, Arizona State University.

The goal of this proposed research project is to develop an advanced microalgal biotechnology that can be integrated into existing nutrient management practices to treat dairy wastewater and to bring it to below USEPA limits for reuse on the farm. The biological principle behind this technology is that photosynthetic microalgae use solar energy to rapidly assimilate nitrogen and phosphorous. A cost-effective photobioreactor will further enhance this biological process and make it economically feasible and environmentally sound. The major objectives of the proposed research are to: 1) evaluate maximum sustainable nutrient uptake potential by isolated microalgal strains growing in dairy wastewater; and 2) construct a novel large-scale column photobioreactor and demonstrate its effectiveness in removing nutrients from wastewater so that the treated water can be recycled.

FY 2005

Salt River Riparian Ecosystem Restoration. $8,869. J. Stromberg, Arizona State University.

This study will monitor the vegetation and surface water in several reaches of the Salt River in the Phoenix metropolitan area prior to implementation of several large-scale restoration actions. The monitoring will provide valuable pre-restoration information to restoration designers, as well as early-stage input on success or failure of the restoration measures.

Big ChinoBasin 3-D Digital Hydrogeologic Framework Model.$9,000. A. Springer, Northern Arizona University.

This study will construct a Digital Hydrogeologic Framework Model (DHFM) to characterize the subsurface geology of Big Chino Basin, located at the headwaters of the Verde River. The DHFM will serve as a tool for understanding and conveying the complex subsurface hydrology of the region to water managers and others. The model will also be utilized by the USGS Water Division in Tucson to construct a Groundwater Flow Model for the region.

Preliminary Evaluation of Perchlorate Contamination of Ground Water in The Lower Colorado River Region. $11,949. C. Sanchez, University of Arizona.

This study will evaluate groundwater in the Yuma area of the lower Colorado River region for perchlorate contamination. Little information presently exists on the extent that seepage from surface water conveyance systems and irrigation drainage has contaminated groundwater sources in the Yuma area.

An Outdoor Multi-Stage, Continuous-Flow Photobioreator for Bioremediation of Nitrate Contaminated Groundwater. $11,740. Q. Hu, and M. Sommerfield, Arizona State University.

This study will design, fabricate and operate a Multiple-stage, Continuous-Flow Photobioreactor (MCP) to remove nitrate from groundwater in a cost-effective and environmentally-friendly way. The photobioreactor will utilize a microalgal species that can thrive in groundwater and take up nitrate at high rates. The algal biomass produced as a by-product from the photobioreactor can be used as an organic fertilizer or animal feed.

Treatment of Nitrate in Groundwater with Autotrophic Bioreactors. $10,000. R. Sierra and J. Field, University of Arizona

The goal of this project is to evaluate the feasibility of a low cost, low maintenance packed-bed bioreactor utilizing insoluble sulfur as the electron donor for denitrification. Additionally, the project investigates the role of naturally occurring groundwater alkalinity in fulfilling neutralization and inorganic carbon requirements of the process. The outcome of the project will be a simple design concept that can be utilized by small water utilities for the affordable and reliable treatment of nitrate in groundwater.

FY 2004

Controlling Salt Accumulation to Enhance Sustainability of Subsurface Drip Irrigation. $11,993. T. Thompson, A. Warrick (UA)

This project provides a framework for evaluating the effects of Subsurface Drip Irrigation (SDI) system architecture, soil characteristics, and environmental conditions on the accumulation of salts in soils irrigated by DSI. Results from the project will be used to calibrate a model to be used to predict salt accumulation with SDI, allowing the optimization of management practices to prevent excessive salt accumulation.

Measurement of Estrogenic Activity in Sludges and Biosolids. $12,305. D. Quarund, W. Ella, R. Arnold, J. Chorover (UA).

The study provides data on (1) procedures for recovery of sorbed hydrophobic estrogenic compounds in soil or biosolids, and (2) total estrogenic activity derived from wastewater treatment and changes in estrogenic activity during anaerobic digestion, dewatering and composting. The project offers method development for extraction of estrogenic activity from solids and baseline information regarding their presence in sludges and biosolids. Project results provide utilities and government agencies with a basis for rational decisions relative to the need for and design of follow-on investigations in this area of inquiry.

Permeable Reactive Biobarriers For The Containment and Remediation of Acid Mine Drainage. $11,678. J. Field, R. Sierra (UA).

This project examines the potential of permeable reactive biobarriers (PRBs) to prevent the spread of acidity, sulfates, and metals from acid mine drainage (AMD) to surface or groundwater. In this project, the activity of sulfate reducing bacteria is promoted in order to convert sulfate to sulfide, which will precipitate a wide spectrum of metal and metalloid contaminants as sulfide minerals. The research specifically examines the applicability of utilizing slow-release electron donating substrates to support microbial activity over extended periods of time. The project will result in the development of a concept for the low-cost containment of AMD. Successful application of this technology will benefit rural citizens living in mining-impacted areas by protecting precious water resources.

Estimation Of Acute Upper Lethal Water Temperature Tolerances Of Native Arizona Fishes $8,100. S. Bonar (UA).

This research provides the upper temperature tolerances of spikedace Meda fulgida, loachminnow Tiaroga cobitis, longfin dace Agosia chrysogaster, speckled dace Rhinichthys osculus , Gila topminnow Poeciliopsis occidentalis occidentalis, Gila chub Gila intermedia, roundtail chub Gila robusta, Yaqui topminnow Poeciliopsis occidentalis sonoriensis, Sonoran sucker Catostomus insignis, and desert sucker Catostomus clarki. . Basic data on the temperature tolerances of a suite of Arizona fishes will be valuable to fisheries managers, hydrologists, and biologists. Hydrologic modeling and other information can often predict what effect a particular land use practice, such as riparian cover removal or water withdrawal will have on the water temperatures of a river. This information is useful for aquatic biologists and managers to help predict how changes in water temperatures might affect the availability of habitat for the existing native fish community of a river.

Impact Of Drought On Management Of Salt Sensitive Plants With Reclaimed Water. $7,000. U. Schuch (UA).

This study develops management strategies on how to manage irrigation of salt sensitive plants with reclaimed water and subjected to frequent drought stress while maintaining functional and aesthetic value of the plants. Six species were grown for 12 weeks with reclaimed or potable water outdoors to expose plants to maximum evaporative demand and heat stress. At the end of the growing period, plants were subjected to increasing levels of water stress alleviated by periods of leaching to determine their response.

FY 2003

Attenuation of Estrogenic Activity in Reclaimed Water and Stormwater During Impoundment in Natural Systems. $12,214. M. Karpisack, W. Ella, D. Quanrud, C. Gerba, R. Arnold, K. Lansey (UA).

This work examines the efficacy of constructed wetlands as a polishing technique for removal of estrogenic activity in wastewater effluent and stormwater runoff. The project provides data on

Site-specific data relevant to the fate of human estrogen and estrogen mimics during effluent polishing operations at the Sweetwater wetlands and Kino wetlands; data on fate of estrogenic activity as function of wetland detention time; Information leading to consensus regarding use-dependent treatment requirements for water reuse application; and, site-specific data on fate of estrogenic activity in stormwater during wetland treatment at the Kino wetlands.

Impacts of Conservation Measures and Alternative Water Supplies on Groundwater. $9,677. A. Springer (NAU).

This project provides a better understanding of the impacts of various conservation measures and alternative water supplies on the recharge to aquifers and volumes of water stored in aquifers. The study developed generic groundwater models to understand the impacts of: different conservation measures on groundwater budgets; different alternative water supplies on groundwater budgets; conservation measures on a calibrated groundwater flow model of a specific aquifer, and; alternative water supplies on a calibrated groundwater flow model of a specific aquifer.

Selection of High Performance Microalgae for Bioremediation of Nitrate-Contaminated Groundwater. $10,550, Q. Hu (ASU).

This project is a step in the development a large-scale engineered microalgal nitrate-striping system for groundwater nitrate removal. Nitrate can be effectively taken up by photosynthetic cyanobacteria and microalgae, which require mostly nitrate, inorganic carbon, and light for growth, t he use of photosynthetic organisms minimizes the need of chemicals and energy from fossil fuels for nitrate removal. An engineered microalgal bioreactor may sustain continuous cultures of a high cell density of desirable organisms, large quantities of raw water can be stripped of nitrate within a short period of time. An engineered microalgal nitrate-striping biotechnology could be a long-term, environmentally safe, and cost-effective approach for large-scale nitrate removal from contaminated groundwater in Arizona . This project specifically isolates and screens a large number of microalgal species collected from major water bodies in the metro Phoenix area, focused on identifying desirable strains that can rapidly assimilate nitrate from groundwater efficiently and effectively.

Integrating Research and Education to Assist Watershed Initiatives: A Survey of Three Arizona Watershed Organizations. $12,451. R. Varady, J. de Steiguer, D. Young, A. Browning-Aiken, R. Meredith (UA).

This study of watershed organizations concludes that collaboration is a process that requires gaining trust among members, agreeing on the nature of the problem(s), having the capacity to bring resources (technology, science, funding, political and economic support) to the table, and a basic knowledge about basin hydrology and water laws. Much of this process revolves around obtaining “collaborative know-how” or learning how to “cooperate and work with organizations that have different values, procedures and processes.” The research objective of “Integrating Research and Education to Assist Watershed Initiatives” was to create a pilot survey instrument to assess watershed organizations in Arizona and to test that instrument in the three watersheds. The three Arizona watersheds tested were the Upper San Pedro, Verde, and Santa Cruz River Basins.