2005 Annual Report 1.What major problem or issue is being resolved and how are you resolving it (summarize project aims and objectives)? How serious is the problem? What does it matter? Water demands in the western US currently exceed available supplies. Population growth and water shortages will increase the need to use treated wastewater effluent for irrigation, particularly in areas where fresh water resources are limited. The use of recycled water for municipal and crop irrigation will reduce groundwater pumping, which currently provides 37% of water for agricultural use and is the largest user of groundwater nationwide. In addition, large quantities of water in arid regions are used for maintaining critical stream flows. Treated effluent is ideal for both of these purposes as long as the constituents found in the effluent will cause no harm to downstream users. This research, focused on understanding the basic fate and transport of pathogens and emerging contaminants, is essential to ensure that treated effluent is used in a safe and sustainable manner. Using present technologies, municipal wastewater treatment may not completely disinfect recycled irrigation waters, allowing pathogenic microbial populations to re-grow in water storage and transmission systems. As a result, recycled water used for agricultural and municipal irrigation can contain enough pathogenic organisms to threaten human health once released into the environment. Moreover, little is known about the long-term environmental fate of synthetic organic compounds, including pharmaceutically active chemicals and disinfection byproducts, contained in recycled wastewater. Overall, the environmental and public health impacts of irrigation with reclaimed sewage effluent and the potential degradation of underlying groundwater are largely unknown. The aim of this research project is to develop novel methods to improve the chemical and microbiological safety of wastewater used for municipal and agricultural irrigation. This project will utilize state-of-the-art soil chemical analyses, microbial cultivation, and molecular biology techniques to evaluate the transport of pathogens and pharmaceutically active chemicals in water distribution systems and in soils with a history of wastewater application. Studies will examine factors affecting pathogen survival, chemical biotransformation, and microbial and chemical transport in soils, and methods of pathogen control in wastewater distribution systems will be tested using laboratory bioreactors and field studies. Taken together, this work will contribute to the development of wastewater irrigation management strategies to minimize the introduction of pathogens and emerging contaminant chemicals into the environment, thus reducing the risk to human health and to groundwater. The current project is the result of merging CRIS 5344-32000-002-00D and CRIS 5344-13000-012-00D in FY 2004. The combined CRIS has a two year duration and has redefined objectives as follows: Objective 1: Develop methods for improved environmental detection of contaminants and pathogens using field studies in areas with a history of wastewater application. Objective 2: Determine the environmental fate and transport of contaminants and pathogens using focused studies in agricultural fields, municipal irrigated areas (golf courses, parks), and/or groundwater recharge areas with a long history of municipal wastewater application. Objective 3: Examine novel methods to control bacterial growth and chemical transport in conveyance systems using laboratory reactor studies, to aid in development of management strategies to minimize environmental impacts of using treated effluent for irrigation. This research directly addresses the national and global problem of food safety in agricultural areas that have been irrigated with sewage effluent or with effluent contaminated water. The research also addresses issues of water conservation and integrated water management through water reuse. These issues now occur or are emerging in many parts of the US and the rest of the world wherever there is insufficient water to meet competing demands for municipal, industrial, and agricultural irrigation. All objectives fall under National Program 201, Water Quality and Management. By addressing water conservation and integrated water management through water reuse, Objectives 1 and 2 fall under Problem Area 2.5 (Waste Water Reuse), Goal 2.5.3 (Waste Water Standards). Objective 3 addresses Problem Area 2.3 (Water Conservation Management), Goal 2.3.1 (Water Conservation Technologies). 2.List the milestones (indicators of progress) from your Project Plan. This is a new project resulting from the combining of two previously independent projects (0404754 and 0405645). A final report for each of the independent projects was written in FY 2004. The combined project will expire in FY 2006 and will span only two years; therefore, the current report will begin with year one (FY 2005) and will document milestones for FY 2005 and projected milestones for the final year of the project (FY 2006). Project Plan Milestones, Year 1 (FY 2005): Environmental Detection of Pathogens and Emerging Contaminants: 1) Verify laboratory and field procedures for determining microbial re-growth in environmental samples. 2) Develop procedures and analytical methods for quantifying organic contaminants in treated effluent from environmental samples. Environmental Fate and Transport of Pathogens and Emerging Contaminants: 1) Establish long-term lysimeter studies under effluent irrigation to determine the fate and transport of contaminants and pathogens found in sewage effluent. 2) Establish methods to link hydraulic properties and nutrient status to the persistence of emerging contaminants and re-growth of pathogens in passive effluent treatment systems. 3) Develop new methods for directed sampling of effluent irrigated turf grass. 4) Determine fundamental fate and transport parameters for emerging contaminants for predictive model input. Management Strategies to Minimize Adverse Impacts of Using Treated Effluent for Irrigation: None planned for year 1 Project Plan Milestones, Year 2 (FY 2006): Environmental Detection of Pathogens and Emerging Contaminants: 1) Regular periodic sampling of model effluent systems. 2) Initiate source tracking of indicator organisms in open systems. 3) Continue long term monitoring of chemical and biological constituents capable of transport through the field lysimeters. 4) Continue monitoring of emerging contaminants in passive effluent treatment systems. Environmental Fate and Transport of Pathogens and Emerging Contaminants: 1) Determine the existence of links between soil salinity and the presence of indicator organisms and other contaminants of interest. 2) Verify experimentally determined fate and transport parameters with small scale leaching studies. Management Strategies to Minimize Adverse Impacts of Using Treated Effluent for Irrigation: 1) Design and build a lab (benchtop-scale) effluent treatment reactor. 4a.What was the single most significant accomplishment this past year? Developed and validated a three-dimensional sampling array for surface waters that significantly increases sampling efficiency by increasing the number of environmental samples that can be obtained and decreasing time required for sample collection. Detailed environmental monitoring is fundamental to environmental protection, but typically the expense and time required for sample collection limits the number of sampling locations and sampling events. The three-dimensional array provides an inexpensive means by which limited manpower is needed to sample multiple locations within surface water bodies. By decreasing time required for sample collection and transport to the laboratory, this sampling array effectively reduces the uncertainty associated with environmental monitoring and increases the confidence in management methods developed using this technology. 4b.List other significant accomplishments, if any. None 4c.List any significant activities that support special target populations. None 4d.Progress report. A study was initiated to evaluate pathogen re-growth in treated wastewater effluent. Collected pathogens are being cultured in the laboratory to utilize in source tracking studies to quantify pathogen sources (human vs. other mammal vs. avian). At present, little is known about the environmental processes controlling pathogen growth and transport in open waters, and how effluent (human-derived) pathogens vs. natural (avian-derived) pathogens contribute to the total pathogen load of these systems. Detailed, regular sampling of treated effluent waters and collection of related environmental data will contribute to the development of models that project areas of maximum pathogen re-growth. Ultimately, these models will be utilized to develop focused means of controlling pathogen growth and transport in open water systems. Studies to determine the fate of organic contaminants found in treated sewage effluent used for irrigation continued. Soil sorption studies were conducted using two compounds typically found in treated sewage effluent. It was found that soils treated with biosolids increased sorption, and therefore retention, of these compounds in the soil. This data will contribute to a comprehensive database of environmental fate parameters for emerging contaminants. This database will eventually be available for inputs into predictive fate and transport models. A number of pieces of laboratory equipment have been acquired, and existing equipment has been refurbished, to provide the necessary analytical capabilities to investigate most of the emerging contaminants found in treated effluent. In addition, a laboratory has been established to process and store samples for microbiological analysis, culture pathogens of interest, and utilize molecular analyses to validate microbiological results. These expanded analytical capabilities will aid in the development of databases detailing environmental controls on the fate and transport of emerging contaminants and human pathogens. Resulting databases will be made available to other researchers for development, calibration and validation of predictive models used in management of agricultural and municipal systems where treated effluent is used for irrigation. Survival of Bulrush in Constructed Wetland Treatment System for Sewage Effluent as Affected by Redox, pH and Microbes Constructed wetlands are potentially an important means of treating sewage effluent before release to surface water bodies. The Tres Rios Constructed Wetlands Demonstration Project at the Phoenix, Arizona 91st Avenue Sewage Treatment Plant experienced a failure of the bulrush population. The Bureau of Reclamation funded a study to evaluate chemical and biological conditions that may have lead to the decline of the wetland plants. A series of oxidation–reduction potential (ORP) and pH sensors have been maintained throughout the wetland for 18 months. Results continue to show that the ecology of the overlying water column is responsible for much of the observed seasonal patterns in pH and ORP. Diurnal patterns were present in the ORP readings only in the spring. The diurnal patterns observed in pH were predominantly in the sediment surface and to a lesser extent at depth. The ORP readings were highest in spring and lowest during summer. The seasonal patterns of both pH and ORP appear to be driven more by floating vegetation and bottom growing algae than by the emergent vegetation. The sustainability of the vegetation at the Tres Rios Wetland is a function of nutrient content and availability. Two hydraulic tracer studies conducted using the three dimensional sampling array indicate that there is bypass flow occurring within the wetland. In addition, one detailed nutrient distribution sampling event was conducted. Water samples were analyzed for essential nutrients, dissolved oxygen, pH, and total salinity as well as type and quantity of dissolved salts. Preliminary results indicate that the distribution of nutrients throughout the wetland correlate with the hydraulic characteristics. Collected samples were also analyzed for microbiological indicator organisms, and their distribution was also highly correlated with the nutrients and hydraulics of the system. 5.Describe the major accomplishments over the life of the project, including their predicted or actual impact. This is a new project resulting from the combination of two previously independent projects (0404754 and 0405645). A final report for each of the independent projects was written in FY 2004. Each of the independent projects had major accomplishments that contributed to the objectives and goals of the combined project. One major accomplishment of the earlier projects was determining that soils treated with biosolids reduced the potential mobility of pharmaceutical compounds in field lysimeters. Little is known about the long-term environmental fate of synthetic organic compounds, including pharmaceutically active chemicals and disinfection byproducts contained in recycled wastewater, and the lysimeter work increased our ability to predict the fate and transport of contaminants found in treated effluent. Thus, the data gathered from the initial field lysimeter studies will contribute to the development of best management practices in reusing sewage effluent. Microbiological work in the earlier projects included a laboratory study to assess the survival and regrowth potential of bacteria present in tertiary-treated effluent as it passed through a model distribution system. The results demonstrated that population numbers of indicator bacterial organisms increased by three to four orders of magnitude over the 11-day length of the experiment. This research established that although the reclaimed water met EPA standards for irrigation at the treatment plant, there is great potential for bacterial regrowth during transport that could place the water out of compliance at the point of intended use. This work illustrated the critical need to understand the environmental fate of microorganisms and the potential for bacterial regrowth in reclaimed water used for crop irrigation so that future problems of food and groundwater contamination via wastewater irrigation can be prevented. 6.What science and/or technologies have been transferred and to whom? When is the science and/or technology likely to become available to the end-user (industry, farmer, other scientists)? What are the constraints, if known, to the adoption and durability of the technology products? None 7.List your most important publications in the popular press and presentations to organizations and articles written about your work. (NOTE: List your peer reviewed publications below). C. Williams. 2005. Is irrigated agriculture sustainable? The battle to counteract salinity. Southwest Hydrology. Volume 4, July/August 2005: 22-23. F.C. Williams and C. Williams. 2005. Conservation-minded guidelines for establishing and maintaining a beautiful and healthy lawn. Information leaflet distributed by the South Davis Sewer District, West Bountiful, UT.