#Rising reuse of wastewater in forecast but world lacks data on massive potential resourceamid growing competition for freshwater from industry and cities coupled with a rising world shortage of potash nitrogen and phosphorus an international study predicts a rapid increase in the use of treated wastewater for farming and other purposes worldwide. However research shows that treated wastewater--comparable in North america alone to the volume of water flowing over Niagara falls--is mostly unused and in many nations not even quantified. Of 181 countries studied only 55 have information on three key aspects of wastewater: generation treatment and reuse. Another 69 countries have data on one or two aspects 57 countries show no information on any aspect. As well in countries where data does exist it is outdated mostly: almost two-thirds (63%)of the numbers are five or more years old according to the study led by Japan's Tottori University and the United nations University's Canadian-based Institute for Water Environment and Health (UNU-INWEH). As water supplies fall and stress rises in many areas the potential resource of wastewater is being recognized widely says the study published Sept. 5 by Elsevier journal Agricultural Water Management. Water demands already exceed supplies in regions with more than 40%of the world's population and in just 12 years as much as 60%of the world's people may confront water scarcity. Synthesizing what data there are on wastewater treatment the study shows that on average high-income countries treat 70%of the generated wastewater upper-middle-income countries treat 38%lower-middle-income countries treat 28%.%Just 8%of wastewater generated in low-income countries undergoes any kind of treatment. In North america of the estimated 85 cubic kilometers of wastewater generated each year 61 cubic kilometers (75%)is treated. A cubic kilometer is 1 trillion liters--about 220 billion US gallons. Annually however just 2. 3 cubic kilometers or 3. 8%of that treated wastewater is used. Tables in the study detail the wastewater generation treatment and reuse--and how up to date the numbers are--in individual countries around the world. From the earliest of times most wastewater has truly been wasted. However it is a vast resource if we reclaim it properly which includes the separation of municipal from industrial wastewater says UNU-INWEH Director Zafar Adeel. Another way of envisioning the volume of the resource potentially available worldwide each year is to imagine 14 months watching the outflow from the Mississippi river into the Gulf of mexico. It has been reported that wastewater today irrigates between 1. 5%and 6. 6%of the global irrigated area of 301 million ha (1. 2 million sq. miles) and that about 10%of world food is produced using wastewater. However according to the study there is little data to support such claims. In developing countries particularly in water scarce countries wastewater volumes are thought to have increased substantially in recent years due to rural-urban migration. Many farmers in water scarce developing countries irrigate with wastewater because: Says lead author Toshio Sato of Tottori University Japan: Given the growing importance of wastewater management to the health of people and economies at local and national levels having up-to-date basic insights into wastewater generation treatment and reuse is an essential investment. The key point underlined throughout this report is need the to invest the time and resources to fill the global data gap adds author Manzoor Qadir of UNU-INWEH. Better data will enable the research and policy community to enhance understanding and craft effective solutions that will benefit millions of producers and consumers worldwide. Says the study on which Tottori University and UNU-INWEH collaborated with the International Center for Agricultural Research in the Dry Areas (ICARDA) Syria the International Water Management Institute (IWMI) Sri lanka and Hazara University Pakistan The country level information aggregated at the regional and global levels would help in identifying the gaps in pertinent data availability and assessing the potential of wastewater in food feed and fish production at different scales. Selected highlightsthe study is the first ever to identify information gaps with respect to wastewater generation treatment and use. About 70%of the world's freshwater (up to 95%in some countries) is used for irrigation. Competition for freshwater already exists among municipal industrial and agricultural sectors particularly in water scarce areas. Agriculture has been yielding its share gradually to nonagricultural uses. The combination of less freshwater allocation to agriculture and growing volumes of urban wastewater is expected to continue and intensify particularly in water scarce countries. Agriculture in these countries will increasingly rely on alternative water resources such as wastewater generated by nonagricultural activities in urban and peri-urban areas. Under-reporting of wastewater generation treatment and reuse might relate to fear of economic repercussions in agricultural trade due to concerns regarding food safety and phytosanitary measures. Jordan's export market for example was impacted in 1991 when countries in the region restricted imports of fruits and vegetables irrigated with inadequately treated wastewater. Jordan implemented an aggressive campaign to rehabilitate and improve wastewater treatment plants introduced enforceable standards to protect the health of farmers and consumers and continues to focus on this sensitive situation given the importance of regional and international trade. North Americathe estimated volume of wastewater generated in North america each year is about 85 cubic kilometers of which 61 cubic kilometers are treated. A cubic kilometer of wastewater is 1 trillion liters--about 220 billion US gallons. Annual use of treated wastewater accounts for 2. 3 cubic kilometers which is only 3. 8%of the wastewater treated in the region. Thus while about 75%of the wastewater generated in North america is treated only a small portion is used. While the data describing wastewater generation and treatment are available in Canada the data on wastewater use are not available. However there are several projects underway suggest the use of wastewater in Canada at pilot scale. An estimated 46%of California's annual reclaimed water use takes place in agriculture. In Florida the proportion is 44%.%Increasingly stressed water resources motivate wastewater use in Arizona California and Texas while limited groundwater motivates water recycling and reuse in Florida. Latin Americacomplete information on wastewater generation treatment and use is available from only 9 of 32 countries: Argentina Bolivia Brazil Chile Dominican republic Guatemala Mexico Nicaragua and Peru. Even this information is relatively old as the data pertain largely to 1996-2002. Ten countries have partial data available: Antigua and barbuda Belize Colombia Costa rica Cuba Ecuador El salvador Panama Paraguay and Venezuela. Only about 20%of generated wastewater undergoes treatment in the Latin american countries for which pertinent data are available in part because many Latin american countries do not have developed well wastewater collection and treatment systems. In 8 of 15 Latin american countries less than half the population is connected to wastewater collection and treatment systemsrapid urbanization without sanitation facilities has caused major downstream pollution problems in this region. The urban population is projected to further increase by 130%in 2025 and by 166%in 2050in Chile untreated wastewater was used directly for agricultural purposes until 1992. With widespread occurrence of cholera in Latin america the direct use of untreated wastewater was restricted in the country. Water scarcity is not the main driver of wastewater use in most of Latin america. Rather farmers engage in wastewater use because it provides a low-cost source of plant nutrients. Wastewater use in the region is given particularly important that the shortages in supply of phosphate and potash fertilizers are projected to increase to 3. 5 and 4. 1 million tons by 2014. Europecomplete information on wastewater generation treatment and use is available for only 10 countries in Europe--Cyprus France Germany Italy Malta Netherland Poland Portugal Spain and United kingdom. Most of this information pertains to the last 10 years. Partial data are available for almost two-thirds of Europe including Austria Belgium Bosnia and herzegovina Bulgaria Croatia Czech republic Denmark Greece Hungary Ireland Luxembourg Kosovo Monaco Montenegro Republic of Macedonia Romania Serbia Slovakia Slovenia Sweden and Switzerland. No data are available for Albania Finland Iceland and Norway. Most of the wastewater generated in Europe (71%)undergoes treatment. In southern Europe reclaimed wastewater is used predominantly for agricultural irrigation (44%of the wastewater projects) and urban or environmental applications (37%of the projects. In Northern europe wastewater is used primarily for environmental applications and industryrussian Federation and Independent States from the Soviet Unioncomplete information on wastewater generation treatment and use is available for 8 countries--Armenia Azerbaijan Kazakhstan Kyrgyzstan Latvia Lithuania Turkmenistan and Uzbekistan (Table 4). Partial data are available for other countries--Belarus Estonia Georgia Republic of Moldova Russian Federation Tajikistan and Ukraine. The volume of wastewater treated in the Russian Federation is about 14 cubic kilometers per year. Nearly 28%of this is treated in accordance with established regulations while the remainder is emitted in inadequately treated form into water bodies. Middle east and North Africathe estimated volume of wastewater generated in the middle East and North africa (MENA) region is 22.3 cubic kilometers per year of which 51%(11.4 cubic kilometers per year) is treated. With the exception of Algeria and Iraq complete information on wastewater generation treatment and use is available from all countries in the region. Treated wastewater use is essential in the water scarce MENA region. Currently 51%of treated wastewater is used for irrigation. Some countries in the region are planning to increase the use of treated wastewater. For example Saudi arabia intends to increase wastewater use to 65%by 2016 (USEPA 2012. Israel already uses 70%of the wastewater generated in the domestic sector. High-income countries in the region use treated wastewater for agricultural and landscape irrigation. In Kuwait only vegetables that are eaten after cooking (potatoes and cauliflower) industrial crops forage crops (alfalfa and barely) and highway landscapes may be irrigated with treated wastewater in Kuwait. Wastewater use represents about 10%of the Israeli national water supply and almost 20%of the water supply for irrigationsub Saharan Africaamong 48 Sub-Saharan African countries complete information on wastewater generation treatment and use is available from only three countries--Senegal Seychelles and South africa. Even this information is old as the data from Seychelles and South africa pertain to 2000 to 2003. The countries with partial data available are Botswana Burkina faso Cote d'ivoire Djibouti Eritrea Ethiopia Ghana Lesotho Mauritania Mauritius Namibia Swaziland and Uganda. No data are available from the remaining 32 countries in the region. Most wastewater goes untreated in Sub-saharan africa where water pollution triggers the spread of waterborne diseases such as diarrhea and cholera. In most cases the wastewater used for in agriculture is polluted. For example untreated wastewater is used for irrigation in the peri-urban zones around Kumasi in Ghana Dakar in Senegal Nairobi in Kenya and Bulawayo in Zimbabwe. Given the inherent uncertainty regarding wastewater quality and nutrient content it is not possible for farmers to optimize the use of nutrients particularly when using untreated wastewater. Oceaniacomplete information on all three aspects of wastewater is available only from Australia. The volume of treated wastewater is available for New zealand but the information on the volume of wastewater generated and treated wastewater used is not available. No information regarding wastewater is available from Fiji and the Solomon islands. About 45%of the 450 wastewater use projects in Oceania are in agriculture sector. In Australia an estimated 0. 35 cubic kilometers of treated wastewater are used annually. This volume accounts for 19%of the wastewater treated in the country and about 4%of the total water supplyin New zealand wastewater is used to irrigate golf courses and for industrial applications but the volumes involved likely are smallasiainformation on all three aspects of wastewater is available from only 5 countries--China India Japan Republic of korea and Vietnam. Partial data are available for 14 countries including Bangladesh Bhutan Cambodia Laos Malaysia Maldives Mongolia Myanmar Nepal Pakistan Philippines Singapore Sri lanka and Thailand. Only about 32%of the wastewater generated in Asia is treatedjapan has adopted a comprehensive strategy for treated wastewater use. In 2009 0. 2 cubic kilometers of treated wastewater were used in the country. More than half was used for environmental purposes such as landscape irrigation recreation and river maintenance. Wastewater use in agriculture and industry is not substantial accounting only for 7%and 1%of the treated wastewater respectively. In addition more than 3%of the treated wastewater is used for toilet-flushing. Japan's wastewater use strategy is somewhat unique as it is focused on meeting urban water needs rather than providing water primarily for agricultural uses. An estimated 1. 3 million ha are irrigated with wastewater in China while an estimated 9500 ha are irrigated with untreated wastewater in Vietnam. At least 2%of the agricultural land around most Vietnamese cities is irrigated with wastewater and much of that land is planted in rice. An estimated 32500 ha are irrigated with wastewater in Pakistan. Most of the wastewater is untreated and yet there are no clear regulations in Pakistan regarding which crops may be irrigated with wastewater. Direct use of untreated wastewater is also common in India where in 1985 an estimated 73000 ha were irrigated with wastewater. The increasing demand for plant nutrients in Asia provides an incentive for farmers and public officials to develop safe methods for distributing and managing wastewater for use in agriculture. Projections suggest that the potash supply in East asia will be much smaller than demand by 2014. The projected annual nutrient deficits for South Asia include 4. 3 million tons for nitrogen 7. 4 million tons for phosphorus and 5. 1 million tons for potash. Story Source: The above story is provided based on materials by United nations University. Note: Materials may be edited for content and length h

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