Reclaimed or recycled water (also called wastewater reuse or water reclamation) is the process of converting wastewater into water that can be reused for other purposes. Reuse may include irrigation of gardens and agricultural fields or replenishing surface water and groundwater (i.e., groundwater recharge). Reused water may also be directed toward fulfilling certain needs in residences (e.g. toilet flushing), businesses, and industry, and could even be treated to reach drinking water standards. This last option is called either "direct potable reuse" or "indirect potable" reuse, depending on the approach used. Colloquially, the term "toilet to tap" also refers to potable reuse.
Reclaiming water for reuse applications instead of using freshwater supplies can be a water-saving measure. When used water is eventually discharged back into natural water sources, it can still have benefits to ecosystems, improving streamflow, nourishing plant life and recharging aquifers, as part of the natural water cycle.
Wastewater reuse is a long-established practice used for irrigation, especially in arid countries. Reusing wastewater as part of sustainable water management allows water to remain as an alternative water source for human activities. This can reduce scarcity and alleviate pressures on groundwater and other natural water bodies.
Achieving more sustainable sanitation and wastewater management will require emphasis on actions linked to resource management, such as wastewater reuse or excreta reuse that will keep valuable resources available for productive uses. This in turn supports human wellbeing and broader sustainability.
Simply stated, reclaimed water is water that is used more than one time before it passes back into the natural water cycle. Advances in wastewater treatment technology allow communities to reuse water for many different purposes. The water is treated differently depending upon the source and use of the water and how it gets delivered.
Cycled repeatedly through the planetary hydrosphere, all water on Earth is recycled water, but the terms "recycled water" or "reclaimed water" typically mean wastewater sent from a home or business through a sewer system to a wastewater treatment plant, where it is treated to a level consistent with its intended use.
Water recycling and reuse is of increasing importance, not only in arid regions but also in cities and contaminated environments.
Already, the groundwater aquifers that are used by over half of the world population are being over-drafted. Reuse will continue to increase as the world’s population becomes increasingly urbanized and concentrated near coastlines, where local freshwater supplies are limited or are available only with large capital expenditure. Large quantities of freshwater can be saved by wastewater reuse and recycling, reducing environmental pollution and improving carbon footprint. Reuse can be an alternative water supply option.
Most of the uses of water reclamation are non potable uses such as washing cars, flushing toilets, cooling water for power plants, concrete mixing, artificial lakes, irrigation for golf courses and public parks, and for hydraulic fracturing. Where applicable, systems run a dual piping system to keep the recycled water separate from the potable water.
|Categories of use||Uses|
|Urban uses||Irrigation of public parks, sporting facilities, private gardens, roadsides; Street cleaning; Fire protection systems; Vehicle washing; Toilet flushing; Air conditioners; Dust control.|
|Agricultural uses||Food crops not commercially processed; Food crops commercially processed; Pasture for milking animals; Fodder; Fibre; Seed crops; Ornamental flowers; Orchards; Hydroponic culture; Aquaculture; Greenhouses; Viticulture.|
|Industrial uses||Processing water; Cooling water; Recirculating cooling towers; Washdown water; Washing aggregate; Making concrete; Soil compaction; Dust control.|
|Recreational uses||Golf course irrigation; Recreational impoundments with/without public access (e.g. fishing, boating, bathing); Aesthetic impoundments without public access; Snowmaking.|
|Environmental uses||Aquifer recharge; Wetlands; Marshes; Stream augmentation; Wildlife habitat; Silviculture.|
|Potable uses||Aquifer recharge for drinking water use; Augmentation of surface drinking water supplies; Treatment until drinking water quality.|
De facto, unacknowledged or unplanned potable reuse refers to a situation where reuse of treated wastewater is, in fact, practiced but is not officially recognized. For example, a wastewater treatment plant from one city may be discharging effluents to a river which is used as a drinking water supply for another city downstream.
Unplanned Indirect Potable Use has existed for a long time. Large towns on the River Thames upstream of London (Oxford, Reading, Swindon, Bracknell) discharge their treated sewage ("non-potable water") into the Thames, which supplies water to London downstream. In the United States, the Mississippi River serves as both the destination of sewage treatment plant effluent and the source of potable water.
There are benefits of using recycled water for irrigation, including the lower cost compared to some other sources and consistency of supply regardless of season, climatic conditions and associated water restrictions. When reclaimed water is used for irrigation in agriculture, the nutrient (nitrogen and phosphorus) content of the treated wastewater has the benefit of acting as a fertilizer. This can make the reuse of excreta contained in sewage attractive.
The irrigation water can be used in different ways on different crops:
In developing countries, agriculture is increasingly using untreated wastewater for irrigation - often in an unsafe manner. Cities provide lucrative markets for fresh produce, so are attractive to farmers. However, because agriculture has to compete for increasingly scarce water resources with industry and municipal users, there is often no alternative for farmers but to use water polluted with urban waste directly to water their crops.
There can be significant health hazards related to using untreated wastewater in agriculture. Wastewater from cities can contain a mixture of chemical and biological pollutants. In low-income countries, there are often high levels of pathogens from excreta. In emerging nations, where industrial development is outpacing environmental regulation, there are increasing risks from inorganic and organic chemicals. The World Health Organization, in collaboration with the Food and Agriculture Organization of the United Nations (FAO) and the United Nations Environmental Program (UNEP), has developed guidelines for safe use of wastewater in 2006. These guidelines advocate a ‘multiple-barrier’ approach wastewater use, for example by encouraging farmers to adopt various risk-reducing behaviours. These include ceasing irrigation a few days before harvesting to allow pathogens to die off in the sunlight, applying water carefully so it does not contaminate leaves likely to be eaten raw, cleaning vegetables with disinfectant or allowing fecal sludge used in farming to dry before being used as a human manure.
The use of reclaimed water to create, enhance, sustain, or augment water bodies including wetlands, aquatic habitats, or stream flow is called "environmental reuse". For example, constructed wetlands fed by wastewater provide both wastewater treatment and habitats for flora and fauna.
The use of reclaimed water to recharge aquifers that are not used as a potable water source.
Planned potable reuse is publicly acknowledged as an intentional project to recycle water for drinking water. There are two ways in which potable water can be delivered for reuse - "Indirect Potable Reuse" (IPR) and "Direct Potable Reuse". Both these forms of reuse are described below, and commonly involve a more formal public process and public consultation program than is the case with de facto or unacknowledged reuse. In ‘indirect’ potable reuse applications, the reclaimed wastewater is used directly or mixed with other sources.
Direct potable reuse is also called "toilet to tap".
Some water agencies reuse highly treated effluent from municipal wastewater or resource recovery plants as a reliable, drought proof source of drinking water. By using advanced purification processes, they produce water that meets all applicable drinking water standards. System reliability and frequent monitoring and testing are imperative to them meeting stringent controls.
The water needs of a community, water sources, public health regulations, costs, and the types of water infrastructure in place, such as distribution systems, man-made reservoirs, or natural groundwater basins, determine if and how reclaimed water can be part of the drinking water supply. Some communities reuse water to replenish groundwater basins. Others put it into surface water reservoirs. In these instances the reclaimed water is blended with other water supplies and/or sits in storage for a certain amount of time before it is drawn out and gets treated again at a water treatment or distribution system. In some communities, the reused water is put directly into pipelines that go to a water treatment plant or distribution system.
Indirect potable reuse (IPR) means the water is delivered to the consumer indirectly. After it is purified, the reused water blends with other supplies and/or sits a while in some sort of storage, man-made or natural, before it gets delivered to a pipeline that leads to a water treatment plant or distribution system. That storage could be a groundwater basin or a surface water reservoir.
Some municipalities are using and others are investigating Indirect Potable Reuse (IPR) of reclaimed water. For example, reclaimed water may be pumped into (subsurface recharge) or percolated down to (surface recharge) groundwater aquifers, pumped out, treated again, and finally used as drinking water. This technique may also be referred to as groundwater recharging. This includes slow processes of further multiple purification steps via the layers of earth/sand (absorption) and microflora in the soil (biodegradation).
IPR or even unplanned potable use of reclaimed wastewater is used in many countries, where the latter is discharged into groundwater to hold back saline intrusion in coastal aquifers. IPR has generally included some type of environmental buffer, but conditions in certain areas have created an urgent need for more direct alternatives.
Direct potable reuse means the reused water is put directly into pipelines that go to a water treatment plant or distribution system. Direct potable reuse may occur with or without “engineered storage” such as underground or above ground tanks.
In a Direct Potable Reuse (DPR) scheme, water is put directly into pipelines that go to a water treatment plant or distribution system. Direct potable reuse may occur with or without “engineered storage” such as underground or above ground tanks. In other words, DPR is the introduction of reclaimed water derived from urban wastewater after extensive treatment and monitoring to assure that strict water quality requirements are met at all times, directly into a municipal water supply system.
IPR occurs through the augmentation of drinking water supplies with urban wastewater treated to a level suitable for IPR followed by an environmental buffer (e.g. rivers, dams, aquifers, etc.) that precedes drinking water treatment. In this case, urban wastewater passes through a series of treatment steps that encompasses membrane filtration and separation processes (e.g. MF, UF and RO), followed by an advanced chemical oxidation process (e.g. UV, UV+H2O2, ozone).
Wastewater reclamation can be especially important in relation to human spaceflight. In 1998, NASA announced it had built a human waste reclamation bioreactor designed for use in the International Space Station and a manned Mars mission. Human urine and feces are input into one end of the reactor and pure oxygen, pure water, and compost (humanure) are output from the other end. The soil could be used for growing vegetables, and the bioreactor also produces electricity.
Aboard the International Space Station, astronauts have been able to drink recycled urine due to the introduction of the ECLSS system. The system costs $250 million and has been working since May 2009. The system recycles wastewater and urine back into potable water used for drinking, food preparation, and oxygen generation. This cuts back on the need for resupplying the space station so often.
Water/wastewater reuse, as an alternative water source, can provide significant economic, social and environmental benefits, which are key motivators for implementing such reuse programmes. Specifically, in agriculture, irrigation with wastewater may contribute to improve production yields, reduce the ecological footprint and promote socioeconomic benefits. These benefits include:
Nonpotable reclaimed water is often distributed with a dual piping network that keeps reclaimed water pipes completely separate from potable water pipes.
In many cities using reclaimed water, it is now in such demand that consumers are only allowed to use it on assigned days. Some cities that previously offered unlimited reclaimed water at a flat rate are now beginning to charge citizens by the amount they use.
For many types of reuse applications wastewater must pass through numerous sewage treatment process steps before it can be used. Steps might include screening, primary settling, biological treatment, tertiary treatment (for example reverse osmosis), and disinfection.
There are several technologies used to treat wastewater for reuse. A combination of these technologies can meet strict treatment standards and make sure that the processed water is hygienically safe, meaning free from bacteria and viruses. The following are some of the typical technologies: Ozonation, ultrafiltration, aerobic treatment (membrane bioreactor), forward osmosis, reverse osmosis, advanced oxidation.
Wastewater is generally treated to only secondary level treatment when used for irrigation.
A pump station distributes reclaimed water to users around the city. This may include golf courses, agricultural uses, cooling towers, or in land fills.
Rather than treating wastewater for reuse purposes, other options can achieve similar effects of freshwater savings:
The cost of reclaimed water exceeds that of potable water in many regions of the world, where a fresh water supply is plentiful. However, reclaimed water is usually sold to citizens at a cheaper rate to encourage its use. As fresh water supplies become limited from distribution costs, increased population demands, or climate change reducing sources, the cost ratios will evolve also. The evaluation of reclaimed water needs to consider the entire water supply system, as it may bring important value of flexibility into the overall system 
Reclaimed water is considered safe when appropriately used. Reclaimed water planned for use in recharging aquifers or augmenting surface water receives adequate and reliable treatment before mixing with naturally occurring water and undergoing natural restoration processes. Some of this water eventually becomes part of drinking water supplies.
A water quality study published in 2009 compared the water quality differences of reclaimed/recycled water, surface water, and groundwater. Results indicate that reclaimed water, surface water, and groundwater are more similar than dissimilar with regard to constituents. The researchers tested for 244 representative constituents typically found in water. When detected, most constituents were in the parts per billion and parts per trillion range. DEET (a bug repellant), and caffeine were found in all water types and virtually in all samples. Triclosan (in anti-bacterial soap & toothpaste) was found in all water types, but detected in higher levels (parts per trillion) in reclaimed water than in surface or groundwater. Very few hormones/steroids were detected in samples, and when detected were at very low levels. Haloacetic acids (a disinfection by-product) were found in all types of samples, even groundwater. The largest difference between reclaimed water and the other waters appears to be that reclaimed water has been disinfected and thus has disinfection by-products (due to chlorine use).
A 2005 study titled "Irrigation of Parks, Playgrounds, and Schoolyards with Reclaimed Water" found that there had been no incidences of illness or disease from either microbial pathogens or chemicals, and the risks of using reclaimed water for irrigation are not measurably different from irrigation using potable water.
A 2012 study conducted by the National Research Council in the United States of America found that the risk of exposure to certain microbial and chemical contaminants from drinking reclaimed water does not appear to be any higher than the risk experienced in at least some current drinking water treatment systems, and may be orders of magnitude lower. This report recommends adjustments to the federal regulatory framework that could enhance public health protection for both planned and unplanned (or de facto) reuse and increase public confidence in water reuse.
Many humans associate a feeling of disgust with reclaimed water and 13% of a survey group said they would not even sip it. Nonetheless, the main health risk for potable use of reclaimed water is the potential for pharmaceutical and other household chemicals or their derivatives (Environmental persistent pharmaceutical pollutants) to persist in this water. This would be less of a concern if human excreta was kept out of sewage by using dry toilets or systems that treat blackwater separately from greywater.
To address these concerns about the source water, reclaimed water providers use multi-barrier treatment processes and constant monitoring to ensure that reclaimed water is safe and treated properly for the intended end use.
There is debate about possible health and environmental effects. To address these concerns, A Risk Assessment Study of potential health risks of recycled water and comparisons to conventional Pharmaceuticals and Personal Care Product (PPCP) exposures was conducted by the WateReuse Research Foundation. For each of four scenarios in which people come into contact with recycled water used for irrigation - children on the playground, golfers, and landscape, and agricultural workers - the findings from the study indicate that it could take anywhere from a few years to millions of years of exposure to nonpotable recycled water to reach the same exposure to PPCPs that we get in a single day through routine activities.
Using reclaimed water for non-potable uses saves potable water for drinking, since less potable water will be used for non-potable uses.
The usage of water reclamation decreases the pollution sent to sensitive environments. It can also enhance wetlands, which benefits the wildlife depending on that eco-system. It also helps to stop the chances of drought as recycling of water reduces the use of fresh water supply from underground sources. For instance, The San Jose/Santa Clara Water Pollution Control Plant instituted a water recycling program to protect the San Francisco Bay area's natural salt water marshes.
Wastewater reuse (planned or unplanned) is an ancient practice, which has been applied since the dawn of human history and is closely connected to the development of sanitation provision.
In the U.S., the Clean Water Act of 1972 mandated elimination of the discharge of untreated waste from municipal and industrial sources to make water safe for fishing and recreation. The US federal government provided billions of dollars in grants for building sewage treatment plants around the country. Modern treatment plants, usually using oxidation and/or chlorination in addition to primary and secondary treatment, were required to meet certain standards.
Los Angeles County's sanitation districts started providing treated wastewater for landscape irrigation in parks and golf courses in 1929. The first reclaimed water facility in California was built at San Francisco's Golden Gate Park in 1932. The Water Replenishment District of Southern California was the first groundwater agency to obtain permitted use of recycled water for groundwater recharge in 1962.
Orange County is located in Southern California, USA, and houses a classic example in indirect potable reuse. A large-scale artificial groundwater recharge scheme exists in the area, providing a much-needed freshwater barrier to intruding seawater. Part of the injected water consists of recycled water, starting as of 1976 with Water Factory 21, which used RO and high lime to clean the water (production capacity of 19,000 m3 per day). This plant was decommissioned in 2004 and has since made place for a new project with a higher capacity (265,000 m3 per day with an ultimate capacity of 492,000 m3 per day), under the name of Groundwater Replenishment System.
The health and environmental safety conditions under which wastewater may be reused are not specifically regulated at the European Union (EU) level. There are no guidelines or regulations at EU level on water quality for water reuse purposes. In the Water Framework Directive, reuse of water is mentioned as one of the possible measures to achieve the Directive’s quality goals, however this remains a relatively vague recommendation rather than a requirement: Part B of Annex VI refers to reuse as one of the “supplementary measures which Member States within each river basin district may choose to adopt as part of the programme of measures required under Article 11(4)”.
Besides that, Article 12 of the Urban Wastewater Treatment Directive concerning the reuse of treated wastewater states that “treated wastewater shall be reused whenever appropriate”, is not specific enough to promote water reuse and it leaves too much room for interpretation as to what can be considered as an “appropriate” situation to reuse treated wastewater.
Despite the lack of common water reuse criteria at the EU level, several Member States (MS) have issued their own legislative frameworks, regulations, or guidelines for different water reuse applications (e.g. Cyprus, France, Greece, Italy, and Spain).
However, after an evaluation carried out by the European Commission (EC) on the water reuse standards of several member states it was concluded that they differ in their approach. There are important divergences among the different standards regarding the permitted uses, the parameters to be monitored, and the limit values allowed. This lack of harmonization among water reuse standards might create some trade barriers for agricultural goods irrigated with reclaimed water. Once on the common market, the level of safety in the producing member states may be not considered as sufficient by the importing countries. The most representative standards on wastewater reuse from European member states are the following:
Reclaimed water is not regulated by the Environmental Protection Agency (EPA), but the EPA has developed water reuse guidelines that were most recently updated in 2012. The EPA Guidelines for Water Reuse represents the international standard for best practices in water reuse. The document was developed under a Cooperative Research and Development Agreement between the U.S. Environmental Protection Agency (EPA), the U.S. Agency for International Development (USAID), and the global consultancy CDM Smith. The Guidelines provide a framework for states to develop regulations that incorporate the best practices and address local requirements.
When there are droughts in Australia interest in reclaimed effluent options increases. Brisbane has been seen as a leader in this trend, and other cities and towns will review the Western Corridor Recycled Water Project once completed.
While there are currently no full-scale direct potable reuse schemes operating in Australia, the Australian Antarctic Division is investigating the option of installing a potable reuse scheme at its Davis research base in Antarctica. To enhance the quality of the marine discharge from the Davis WWTP, a number of different, proven technologies have been selected to be used in the future, such as ozonation, UV disinfection, chlorine, as well as UF, activated carbon filtration and RO.
As of 2010, Israel leads the world in the proportion of water it recycles. Israel treats 80% of its sewage (400 billion liters a year), and 100% of the sewage from the Tel Aviv metropolitan area is treated and reused as irrigation water for agriculture and public works. As of today, all the reclaimed sewage water in Israel is used for agricultural and land improvement purposes.
An example of direct potable reuse is the case of Windhoek (Namibia, New Goreangab Water Reclamation Plant (NGWRP)), where treated wastewater has been blended with drinking water for more than 40 years. It is based on the multiple treatment barriers concept (i.e. pre-ozonation, enhanced coagulation/dissolved air flotation/rapid sand filtration, and subsequent ozone, biological activated carbon/granular activated carbon, ultrafiltration (UF), chlorination) to reduce associated risks and improve the water quality. The reclaimed wastewater nowadays represent about 14% of the city’s drinking water production.
In Singapore reclaimed water is called NEWater and is bottled directly from an advanced water purification facility for educational and celebratory purposes. Though most of the reused water is used for high-tech industry in Singapore, a small amount is returned to reservoirs for drinking water.
At the end of 2002, the programme - successfully branded as NEWater - had garnered a 98 percent acceptance rate, with 82% of respondents indicating that they would drink the reused water directly, another 16% only when mixed with reservoir water. The produced NEWater after stabilization (addition of alkaline chemicals) is in compliance with the WHO requirements and can be piped off to its wide range of applications (e.g. reuse in industry, discharge to a drinking water reservoir). NEWater now makes up around 30% of Singapore’s total use, by 2060 Singapore’s National Water Agency plans to triple the current NEWater capacity as to meet 50% of Singapore’s future water demand.
In South Africa, the main driver for wastewater reuse is drought conditions.
For example, in Beaufort West, South Africa’s a direct wastewater reclamation plant (WRP) for the production of drinking water was constructed in the end of 2010, as a result of acute water scarcity (production of 2,300 m3 per day). The process configuration based on multi-barrier concept and includes the following treatment processes: sand filtration, UF, two-stage RO, and permeate disinfected by ultraviolet light (UV).
In a January 2012 U.S. National Research Council report, a committee of independent experts found that expanding the reuse of municipal wastewater for irrigation, industrial uses, and drinking water augmentation could significantly increase the United States’ total available water resources.
One example is Orange County which is located in Southern California, USA, and houses a classic example in indirect potable reuse. A large-scale artificial groundwater recharge scheme exists in the area, providing a much-needed freshwater barrier to intruding seawater.
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Alumni Park, is a private park owned by Pepperdine University in Malibu, California. The park is a 30 acre expanse of trails, lawns, hills, ponds and coral trees. The 40,000 square feet ponds are considered open reservoirs of reclaimed water. The park hosts an annual Waves of Flags display. Nearly 3,000 flags are displayed each September to commemorate each of the lives lost in the September 11 attacks.Alumni Park is the home course for the Pepperdine Waves men's and women's cross country teams. It hosted the 2013 West Coast Conference cross country championship.The park is used for university graduation ceremonies and is also used for music events.Aquifer storage and recovery
Aquifer storage and recovery (ASR) is the direct injection of surface water supplies such as potable water, reclaimed water (i.e. rainwater), or river water into an aquifer for later recovery and use. The injection and extraction is often done by means of a well. In areas where the rainwater can not percolate the soil or where it is not capable of percolating it fast enough (i.e. urban areas) and where the rainwater is thus diverted to rivers, rainwater ASR could help to keep the rainwater within an area. ASR is used for municipal, industry and agriculture use.Athlone Power Station
Athlone Power Station was a coal-fired power station in Athlone, Cape Town, South Africa. The site stopped generating power in 2003 and is in the process of being decommissioned.Athlone Power Station was situated on the N2 freeway into the city, consisted of a large brick generation building, two 99m brick chimneys, and two cooling towers, fed by reclaimed water from a nearby sewage plant. It was commissioned in 1962 with 6 turbines with a nominal capacity of 180 megawatts, and operated by the City of Cape Town. Between 1985 and 1994 the station was held on standby, but it resumed generating in 1995 with a reduced capacity of 120 MW. Between 1995 and 2003 it was mainly used to generate power in peak demand periods and during power failures of the national grid. In 2003, significant investment was required due to the age of the power station, and generation was stopped.Drinking water supply and sanitation in the United States
Issues that affect drinking water supply and sanitation in the United States include water scarcity, pollution, a backlog of investment, concerns about the affordability of water for the poorest, and a rapidly retiring workforce. Increased variability and intensity of rainfall as a result of climate change is expected to produce both more severe droughts and flooding, with potentially serious consequences for water supply and for pollution from combined sewer overflows. Droughts are likely to particularly affect the 66 percent of Americans whose communities depend on surface water. As for drinking water quality, there are concerns about disinfection by-products, lead, perchlorates and pharmaceutical substances, but generally drinking water quality in the U.S. is good.
Cities, utilities, state governments and the federal government have addressed the above issues in various ways. To keep pace with demand from an increasing population, utilities traditionally have augmented supplies. However, faced with increasing costs and droughts, water conservation is beginning to receive more attention and is being supported through the federal WaterSense program. The reuse of treated wastewater for non-potable uses is also becoming increasingly common. Pollution through wastewater discharges, a major issue in the 1960s, has been brought largely under control.
Most Americans are served by publicly owned water and sewer utilities. Any public system, which is defined as a system that serves more than 25 customers or 15 service connections, is regulated by the U.S. Environmental Protection Agency under the Safe Water Drinking Act. Eleven percent of Americans receive water from private (so-called "investor-owned") utilities. In rural areas, cooperatives often provide drinking water. Finally, up to 15 percent of Americans are served by their own wells. Water supply and wastewater systems are regulated by state governments and the federal government. At the state level, health and environmental regulation is entrusted to the corresponding state-level departments. Public Utilities Commissions or Public Service Commissions regulate tariffs charged by private utilities. In some states they also regulate tariffs by public utilities. At the federal level, drinking water quality and wastewater discharges are regulated by the Environmental Protection Agency (EPA), which also provides funding to utilities through State Revolving Funds.
Water consumption in the United States is more than double that in Central Europe, with large variations among the states. In 2002 the average American family spent $474 on water and sewerage charges, which is about the same level as in Europe. The median household spent about 1.1 percent of its income on water and sewage. By 2018, 87% of the American population receives water from publicly owned water companies.Dual piping
Dual piping is a system of plumbing installations used to supply both potable and reclaimed water to a home or business. Under this system, two completely separate water piping systems are used to deliver water to the user. This system prevents mixing of the two water supplies, which is undesirable, since reclaimed water is usually not intended for human consumption.
In the United States, reclaimed water is distributed in lavender (light purple) pipes, to alert users that the pipes contain non-potable water. Hong Kong has used a dual piping system for toilet flushing with sea water since the 1950s.
According to the El Dorado Irrigation District in California, the average dual-piped home used approximately 0.17 acre feet (210 m3) of potable water in 2006. The average single family residence with traditional piping using potable water for irrigation as well as for domestic uses used between 0.63 acre feet (780 m3), higher elevation, and 0.78 acre feet (960 m3), lower elevation.Groundwater recharge
Groundwater recharge or deep drainage or deep percolation is a hydrologic process, where water moves downward from surface water to groundwater. Recharge is the primary method through which water enters an aquifer. This process usually occurs in the vadose zone below plant roots and, is often expressed as a flux to the water table surface. Groundwater recharge also encompasses water moving away from the water table farther into the saturated zone. Recharge occurs both naturally (through the water cycle) and through anthropogenic processes (i.e., "artificial groundwater recharge"), where rainwater and or reclaimed water is routed to the subsurface.Hyperion sewage treatment plant
The Hyperion Water Reclamation Plant is a sewage treatment plant in southwest Los Angeles, California, next to Dockweiler State Beach on Santa Monica Bay. The plant is the largest sewage treatment facility in the Los Angeles Metropolitan Area and one of the largest plants in the world. Hyperion is operated by the City of Los Angeles, Department of Public Works, and the Bureau of Sanitation. Hyperion is the largest sewage plant by volume west of the Mississippi River.LA City Sanitation operates the largest wastewater collection system in the US, serving a population of four million within a 600 square mile service area. LA's more than 6,700 miles of public sewers convey 400 million gallons per day of flow from customers to LASAN's four plants.Las Vegas Wash
Las Vegas Wash is a 12-mile-long channel which feeds most of the Las Vegas Valley's excess water into Lake Mead. The wash is sometimes called an urban river, and it exists in its present capacity because of an urban population. The wash also works in a systemic conjunction with the pre-existing wetlands that formed the oasis of the Las Vegas Valley. The wash is fed by urban runoff, shallow ground water, reclaimed water, and stormwater.The wetlands of the Las Vegas Valley act as the kidneys of the environment, cleaning the water that runs through it. The wetlands filter out harmful residues from fertilizers, oils, and other contaminants that can be found on the roadways and in the surrounding desert.
Near its terminus at Las Vegas Bay, the wash passes under the man made Lake Las Vegas through two 7-foot pipes.NEWater
NEWater is the brand name given to reclaimed water produced by Singapore's Public Utilities Board. More specifically, it is treated wastewater (sewage) that has been purified using dual-membrane (via microfiltration and reverse osmosis) and ultraviolet technologies, in addition to conventional water treatment processes. The water is potable and is consumed by humans, but is mostly used by industries requiring high purity water.Overdrafting
Overdrafting is the process of extracting groundwater beyond the equilibrium yield of the aquifer.
There are two sets of yields, safe yield and sustainable yield. Safe yield is the amount of water that can be taken out of the ground without there being any undesirable results. Sustainable yield is extraction that takes into account both recharge rate and surface water impacts.
There are two types of aquifers: confined and unconfined. In confined aquifers, there is an overbearing layer called aquitard, which contains impermeable materials through which groundwater cannot be extracted. In unconfined aquifers, there is no aquitard, and groundwater can be freely extracted from the surface. Extracting groundwater from unconfined aquifers is like borrowing the water, it has to be recharged at a proper amount. If recharge is not done in proper amounts there can be many impacts. Recharge may happen through artificial recharge and natural recharge.Natural process of recharge is done through percolation of surface water. Artificial process of recharging the aquifer is through means of pumping reclaimed water from wastewater management projects directly into the aquifer. An example is the Orange County Water District in the State of California. This organization take waste water, treats it to a proper level, and then systematically pumps it back into the aquifers for artificial recharge.
When groundwater is extracted the water is primarily pulled from the aquifer which creates a cone depression around the well. When drafting of water continues the cone of depression increases in width. The increase in width leads to the negative impacts caused by overdrafting, such as drop of the water table, land subsidence, and loss of surface water reaching the streams. In extreme cases the supply of water to naturally recharge the aquifers is pulled directly from streams and rivers, leading to depletion of water levels in streams and rivers. The depletion of water in rivers and streams has an effect on wildlife, as well as humans who might be using the water for other purposes.Since every groundwater basin recharges at a different rate depending upon precipitation, vegetative cover and soil conservation practises, the quantity of groundwater that can be safely pumped varies greatly among regions of the world and even within provinces. Some aquifers require a very long time to recharge and thus the process of overdrafting can have consequences of effectively drying up certain sub-surface water supplies. Subsidence occurs when excessive groundwater is extracted from rocks that support more weight when saturated. This can lead to a capacity reduction in the aquifer.Groundwater is the fresh water that can be found underground; it is also one of the largest sources. Groundwater depletion can be comparable to ¨money in a bank¨, The primary cause of groundwater depletion is pumping or the excessive pulling up of groundwater from underground aquifers.Reedy Creek Energy Services
Reedy Creek Energy Services (RCES) is a wholly owned subsidiary of The Walt Disney Company. It operates the electric and other utility transmission and distribution systems of the Reedy Creek Improvement District (RCID) on behalf of the district which specifically covers Walt Disney World outside Orlando, Florida. Some power is produced by the district-owned power plant north of The Magic Kingdom with the remainder purchased from the public power grid. Officially the utility systems are owned by the district entity itself and the district "contracts" with RCES to operate the systems.
In addition to electric power, RCES handles all public services and public works for the RCID:
Fuel oil distribution
Potable water (drinking)
Sewage and wastewater treatment
Recycling and drainage control
Roadway maintenanceRCES is currently Disney's only non-entertainment-related subsidiary. Until 2001, Disney and Sprint owned Vista-United Telecommunications, a telephone company that served the RCID. That company has since been sold to Smart City Telecom.Sewer mining
Sewer mining (or sewage mining) is a concept where municipal wastewater (sewage) is pumped from a trunk sewer and treated on-site to accommodate a range of local, nonpotable water needs. It is a strategy for combating water scarcity. It combines decentralized wastewater management and water reclamation. Since 2012, it is used as a tool for improving water management and promoting reuse of water in Australia.Soho (Tampa)
SoHo Tampa, short for "South Howard Avenue (Tampa)" is an residential district within the Hyde Park neighborhood of Tampa. Some of the main cross streets are Kennedy Boulevard (SoHo's starting point), Cleveland Street, Platt Street and Swann Avenue. The area has historic architecture and is within walking distance of Bayshore Boulevard where it terminates (two miles away from the entertainment district). The much praised Bern's Steak House is located in the district. Other high-end restaurants and nightlife venues are located here. Other offerings are high-end locally owned clothing boutiques, art galleries, dessert cafes, and a Starbucks. One of only three Publix GreenWise Markets is also located in the district. As of 2009, small companies have sprung up utilizing NEVs to shuttle clubgoers between core neighborhoods including SoHo and Channelside.In 2009 a small park dedicated to Bern Laxer, late founder of Bern's Steakhouse, opened at the southern part of the district. At the center of the park is the "Three Graces" sculpture and a lighted fountain that is the first in Tampa to use reclaimed water.Temple Crest
Temple Crest is a neighborhood and district located in northeastern part of Tampa, Florida. The population was 8,621 at the 2000 census.The Japanese Garden
The Japanese Garden is a 6.5 acres (2.6 ha) public Japanese garden located on the grounds of the Tillman Water Reclamation Plant adjacent to Woodley Park, in the Sepulveda Basin Recreation Area of the central San Fernando Valley. It is in the community of Lake Balboa, adjacent to the Van Nuys and Encino neighborhood.The garden's Japanese name is Suihō-en (水芳園) meaning "garden of water and fragrance." The idea of having a Japanese Garden adjacent to a water reclamation plant was conceived by Donald C. Tillman. The garden’s purpose was to demonstrate a positive use of reclaimed water, in what is usually considered a delicate environment, a Japanese garden. The ponds and irrigation use reclaimed water from the adjacent water reclamation plant.Water management in Beijing
Beijing, the capital of China, is characterized by intense water scarcity during the long dry season as well as heavy flooding during the brief wet season. Beijing is one of the most water-scarce cities in the world. Total water use is 3.6 billion cubic meters, compared to renewable fresh water resources of about 3 billion cubic meters. The difference is made up by the overexploitation of groundwater. Two-thirds of the water supply comes from groundwater, one third from surface water. Average rainfall has substantially declined since the 1950s. Furthermore, one of the two main rivers supplying the city, the Yongding River, had to be abandoned as a source of drinking water because of pollution. Water savings in industry and agriculture have compensated for these losses and freed up water for residential uses.Water tariffs have been increased to provide an incentive to curb residential water demand, but the impact has been limited. Residential demand increases due to population growth, and the city taps new water sources. For example, water reclamation has been aggressively promoted since the turn of the century. The city's 15 central municipal wastewater treatment plants and more than 300 small, decentralized plants now provide reclaimed water for non-potable uses. An additional 1.2 billion cubic meter is expected to be provided through the southern section of the South-North Water Transfer Project's central route from the Han River, more than 1,000 km to the south, until the end of 2014. The supply of desalinated seawater from existing desalination plants near Tianjin is also being contemplated.Water supply and sanitation in Israel
Water supply and sanitation in Israel are intricately linked to the historical development of Israel. Because rain falls only in the winter, and largely in the northern part of the country, irrigation and water engineering are considered vital to the country's economic survival and growth. Large scale projects to desalinate seawater, direct water from rivers and reservoirs in the north, make optimal use of groundwater, and reclaim flood overflow and sewage have been undertaken. Among them is the National Water Carrier, carrying water from the country's biggest freshwater lake, the Sea of Galilee, to the northern Negev desert through channels, pipes and tunnels. Israel's water demand today outstrips available conventional water resources. Thus, in an average year, Israel relies for about half of its water supply on unconventional water resources, including reclaimed water and desalination. A particularly long drought in 1998–2002 had prompted the government to promote large-scale seawater desalination.Water supply and sanitation in Jordan
Water supply and sanitation in Jordan is characterized by severe water scarcity, which has been exacerbated by forced immigration as a result of the 1948 Arab–Israeli War, the Six-Day War in 1967, the Gulf War of 1990, the Iraq War of 2003 and the Syrian Civil War since 2011. Jordan is considered as one of the ten most water scarce countries in the world. High population growth, the depletion of groundwater reserves and the impacts of climate change are likely to aggravate the situation in the future.
The country's major surface water resources, the Jordan River and the Yarmouk River, are shared with Israel and Syria who leave only a small amount for Jordan. The Disi Water Conveyance Project from the non-renewable Disi aquifer to the capital Amman, opened in July 2013, increases available resources by about 12%. It is planned to bridge the remaining gap between demand and supply through increased use of reclaimed water and desalinated sea water to be provided through the Red Sea-Dead Sea canal.
Despite Jordan's severe water scarcity, more than 97% of Jordanians have access to an improved water source and 93% have access to improved sanitation. This is one of the highest rates in the Middle East and North Africa. However, water supply is intermittent and it is common to store water in rooftop tanks. The level of water lost through leakage, underregistration, and theft in municipal water supply (non-revenue water) is approximately 51%. Water tariffs are subsidized. A National Water Strategy, adopted in 2009, emphasizes desalination and wastewater reuse. The country receives substantial foreign aid for investments in the water sector, accounting for about 30% of water investment financing.Water supply and sanitation in Singapore
Water supply and sanitation in Singapore is characterised by a number of achievements in the challenging environment of a densely populated island. Access to water is universal, affordable, efficient and of high quality. Innovative integrated water management approaches such as the reuse of reclaimed water, the establishment of protected areas in urban rainwater catchments and the use of estuaries as freshwater reservoirs have been introduced along with seawater desalination in order to reduce the country's dependence on water imported from neighbouring country, Malaysia.
Singapore's approach does not rely only on physical infrastructure, but it also emphasizes proper legislation and enforcement, water pricing, public education as well as research and development. In 2007 Singapore's water and sanitation utility, the Public Utilities Board, received the Stockholm Industry Water Award for its holistic approach to water resources management.
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