Catálogo de publicaciones - libros

A general trend exists toward increasing the salt concentration of surface and ground waters in the semiarid regions of the world. Quantitative knowledge on the interaction between irrigation management and crop yield is becoming increasingly important as water salinities increase. Guidelines for irrigation management with saline waters which have been based on steady-state analyses overpredict the amount of irrigation required, and/or underestimate the yield that can be achieved when irrigating with saline waters.

Water withdrawal and irrigation in arid zones increase salt concentration in aquifers. The utilization of effluent further augments the concentration by adding salt from households and industry. A sustainable salt regime can be maintained if salt is removed from at least some of the water sources. The paper analyzes theoretically the pricing of water and effluent in a sustainable regime for the coastal aquifer in Israel.

A single-year planning model being developed for a region in Israel which consists of a city and three potential wastewater consumers. The model incorporates, in one endogenous system, the economic, physical, and biological relationships in the water-soil-plant-environment system and its objective is to maximize the regional social welfare composed of the sum of agricultural and environmental net benefits. The model determines the optimal crop mix and the optimal allocation of the limited water and land resources among all potential users.

An approach is presented to model the deterioration of buried, infrequently inspected infrastructure, using scarce data. The robustness of the process is combined with the flexibility of fuzzy mathematics to arrive at a decision framework that is tractable and realistic. In applying this approach to sewerage infrastructure, the scoring scheme was converted using current guidelines. A rule-based model is used to replicate and predict the possibility of failure. The model can be used to plan the renewal of the asset subject to maximum risk tolerance. The concepts are demonstrated using data obtained from Canadian municipalities.

The growing number of municipal wastewater treatment plants in Portugal delivers about 500 million m of treated wastewater that is discharged in river and coastal waters, representing a pollutant load to receiving waters and yet the waste of water resources which could be successfully used for irrigation in agriculture, landscape, golf courses, water reservoirs for fire protection. Because water reuse can contribute to the economic development it must be stimulated by central, regional, and local authorities, but within the framework of good practices and their monitoring. This paper presents the new Portuguese standard NP 4434 that presents guidelines on water quality, irrigation practice, management of environmental impacts, protection of public and animal health and, aspects of control and monitoring.

The aims of this paper are twofold. First, to investigate farmers' opinion of adoption of a new program, which involves utilization of recycled water to replenish an aquifer. Second, to evaluate the economic viability of this new program. A contingent valuation study is undertaken with 97 farmers located near the Akrotiri aquifer in Cyprus, a common-pool water resource with rapidly deteriorating water quality and quantity. The results reveal that farmers are willing to adopt the new technology, and they derive higher values from a recycled wastewater use program, which provides high quality water, and high water quantity in the aquifer.

After several years of intensive research, study, and consultations with world experts in public health, epidemiology, agronomics, environmental sciences, and engineering, as well as other UN agencies, the WHO, in 2006, has published a revised updated volume of the guidelines for the safe use of wastewater, excreta, and gray water. These new guidelines drafted by a panel of 35 experts are recognized as representing the position of the United Nations system on issues of wastewater, excreta, and gray water use and health by “UN-Water.”

The combination of severe water shortage, densely populated urban areas, and highly intensive irrigated agriculture, makes it essential that Israel put wastewater treatment and reuse high on its list of national priorities. Sewage treatment effluent is the most readily available water source and provides a partial solution to the water scarcity problem. National policy calls for the gradual replacement of freshwater because of the decision to increase the use of effluent and set up a committee to review existing regulations and to recommend new regulations for effluent use for irrigation or disposal to stream and receiving water. The recommended values were designed to minimize potential damage to water sources.

Wastewater treatment plants in Israel treat approximately 500 million cubic meters a year. The high quality treated wastewater is used mainly for large-scale agricultural irrigation. Israel has acquired much experience in adjusting the treatment level of the wastewater treatment plants and the qualities and characteristics of the treated wastewater to land and crops. The economic advantage of utilizing the treated wastewater in agriculture substantiates the policy of assisting recycling plants and farmers, with the reuse of treated wastewater enabling the conversion of expensive freshwater.

Wastewater reuse, along with wastewater treatment facilities are endowed with a number of risks that may inflect some serious damage to man and his environment. Decision construct and decision making of wastewater issues are of prime importance for sound use of wastewater and treatment processes. Equally important is the sound economical attributes wastewater treatment and wastewater alternative methods and construction should manifest. Measures of common use in this respect are mostly dominated by environmental impact assessment, risk assessment, and cost benefit analysis. Life cycle assessment (LCA) is one of the newly emerging techniques with wide application in the field of wastewater reuse and wastewater treatment facilities.