From the Proceedings of the 1995 Meetings of the Arizona Section - American Water Resources Association and the Hydrology Section - Arizona-Nevada Academy of Science - April 22, 1995, Northern Arizona University, Flagstaff, Arizona

From the Proceedings of the 1995 Meetings of the Arizona Section - American Water Resources Association and the Hydrology Section - Arizona-Nevada Academy of Science - April 22, 1995, Northern Arizona University, Flagstaff, Arizona

From the Proceedings of the 1995 Meetings of the Arizona Section - American Water Resources Association and the Hydrology Section - Arizona-Nevada Academy of Science - April 22, 1995, Northern Arizona University, Flagstaff, Arizona

From the Proceedings of the 1991 Meetings of the Arizona Section - American Water Resources Association and the Hydrology Section - Arizona-Nevada Academy of Science - April 20, 1991, Northern Arizona University, Flagstaff, Arizona / As the Southwest United States grows and develops, one basic resource becomes a primary necessity for survival: Water. Currently, accepted sources are being consumed at a higher rate than nature replenishes them. This is necessitating the need to find and develop new water resources. In conjunction with the proper treatment and management, wastewater is a water resource, known as reuse. Properly managed, reused water can augment the available water supply. Primary applications include irrigation of agricultural and landscaped areas, surface water recreational areas, and groundwater recharge. These uses relieve the demands on the generally accepted water resources, thus increasing the net water supply. The required level of treatment varies with the intended reuse application. Treatment levels for reuse range from secondary to tertiary treatment systems. Some reuse applications provide additional treatment to the water. The reuser must assure that the treatment system and reuse application provide an equal or improved water quality to that of the receiving body of water. Regardless of the application, stringent operation and maintenance of the reuse system is essential. A well planned management program will minimize hazards associated with reuse of wastewater. This program is required to keep the liabilities of both the treatment plant and reuse site owners to a minimum. Without this, reuse is not a viable option. The underlying questions remain to determine the feasibility of reuse for a community: Does the water supply require augmentation to meet the demands of the future? Is the Owner willing to address and implement a diligent system management program?

From the Proceedings of the 1991 Meetings of the Arizona Section - American Water Resources Association and the Hydrology Section - Arizona-Nevada Academy of Science - April 20, 1991, Northern Arizona University, Flagstaff, Arizona / Since the spring of 1988 the University of Arizona has conducted nanofiltration research. The major emphasis has been the treatment of both Colorado River Water and municipal effluent. The work has been sponsored by the John F. Long Foundation Inc. and the Consolidated Water Utilities, Phoenix Az. Nanofiltration is a low pressure form of reverse osmosis. It operates at about 1/3 the pressure and 3 times the flux rate of older brackish water reverse osmosis systems. This reduces both the cost as well as the operating costs to approximately 1 /10 of the older reverse osmosis systems. The City of Ft Myers is projecting costs as low as $0.50-0.60/1000 gallons for their 20 MGD plant. Nanofiltration treats water the way it needs to be treated to meet the Environmental Protection Agency's (EPA) present minimum contamination levels (MCL) as well as projected future levels. Nanofiltration removes most of the bivalent inorganic molecules such as calcium and magnesium as well as some monovalent molecules such as sodium and chloride. It also removes pathogens and dissolved organics, thus reducing the trihalomethane formation potential (THMFP). The research on recharged effluent municipal effluent below the 91st Avenue Plant in Phoenix has shown the value of nanofiltration for reclaiming municipal wastewater to potable standards. A 20,000 GPD slowsand /nanofiltration pilot plant at Apache Junction has shown the effectiveness of the treatment on Colorado River Water at a 95% recovery over the past 2 years.

From the Proceedings of the 1991 Meetings of the Arizona Section - American Water Resources Association and the Hydrology Section - Arizona-Nevada Academy of Science - April 20, 1991, Northern Arizona University, Flagstaff, Arizona / The use of geographic information systems (GIS) for assessing the hydrologic effects of management is increasing. In the near future most of our spatial or "mapped" information will come from GIS. The direct linkage of hydrologic simulation models to GIS should make the assessment process more efficient and powerful, allowing managers to quickly evaluate different landscape designs. This study investigates the effect the resolution of GIS databases have on hydrological simulation results from an urban watershed. The hydrologic model used in the study was the Soil Conservation Service Curve Number Model which computes the volume of runoff from rainfall events. A GIS database was created for High School Wash, a urban watershed in Tucson, Arizona. Fifteen rainfall-runoff events were used to test the simulation results. Five different grid sizes, ranging from 25x25 square feet to 300x300 square feet were evaluated. The results indicate that the higher the resolution the better the simulation results. The average ratio of simulated over observed runoff volumes ranged from 0.98 for the 25x25 square feet case to 0.43 for the 300x300 square feet case.

From the Proceedings of the 1991 Meetings of the Arizona Section - American Water Resources Association and the Hydrology Section - Arizona-Nevada Academy of Science - April 20, 1991, Northern Arizona University, Flagstaff, Arizona

From the Proceedings of the 1991 Meetings of the Arizona Section - American Water Resources Association and the Hydrology Section - Arizona-Nevada Academy of Science - April 20, 1991, Northern Arizona University, Flagstaff, Arizona / In August 1990, a team of North American and Soviet researchers travelled to several cities on the shores of Lake Baikal in southern Siberia. The purpose of the investigation was to develop a means of protecting and restoring the world's oldest and largest volume lake. Lack of water resource management strategies was identified as the key factor which may result in further deterioration of lake water quality and the diversity of biota which it supports. Deforestation, antiquated agricultural practices, inadequate solid and liquid waste disposal, and industrial contamination threaten the aesthetic quality and commercial uses of the lake. The recommendations of the joint investigative committee are summarized.

From the Proceedings of the 1991 Meetings of the Arizona Section - American Water Resources Association and the Hydrology Section - Arizona-Nevada Academy of Science - April 20, 1991, Northern Arizona University, Flagstaff, Arizona / Legal, legislative, technical and conservation factors have created a significant amount of reclaimed water reuse in Arizona. Critical recent events include: * Passage of the 1980 Groundwater Management Act * Arizona Department of Water Resources Management Plans * Passage of Environmental Quality Act * Creation of Arizona Department of Environmental Quality * 1989 Arizona Supreme Court Decision of the Status of Effluent * 1991 Arizona Reuse Rule Adoption Status

From the Proceedings of the 1995 Meetings of the Arizona Section - American Water Resources Association and the Hydrology Section - Arizona-Nevada Academy of Science - April 22, 1995, Northern Arizona University, Flagstaff, Arizona