The goals of water conservation efforts include:
Ensuring availability of water for future generations where the withdrawal of freshwater from an ecosystem does not exceed its natural replacement rate.
Energy conservation as water pumping, delivery and wastewater treatment facilities consume a significant amount of energy. In some regions of the world over 15% of total electricity consumption is devoted to water management.
Habitat conservation where minimizing human water use helps to preserve freshwater habitats for local wildlife and migrating waterfowl, but also water quality.
Causes of water pollution
In surface waters
Plane entry of pollutants from the air
Pollutants released by accidents in industry or traffic (eg tanker accidents, accidents or major fires in industrial plants)
Pesticides
the discharge of untreated sewage
by washing out over-fertilized agricultural land
In the groundwater
the water-soluble or liquid components of illegally deposited waste from private households, industry and commerce
Wastewater from leaking sewer pipes
excessive fertilization of fields with manure and manure mainly from factory farming
Intentionally or unintentionally released pollutants in industrial or commercial enterprises (eg by undetected line leakages, negligent behavior of employees, industrial accidents, in earlier times also due to lack of awareness of the problem)
Mineral oils, de-icing salts and residues from transport and transport
Pesticides from agriculture
Strategies
The key activities that benefit water conservation(save water) are as follows:
Any beneficial reduction in water loss, use and waste of resources.
Avoiding any damage to water quality.
Improving water management practices that reduce the use or enhance the beneficial use of water.
One strategy in water conservation is rain water harvesting. Digging ponds, lakes, canals, expanding the water reservoir, and installing rain water catching ducts and filtration systems on homes are different methods of harvesting rain water. Harvested and filtered rain water could be used for toilets, home gardening, lawn irrigation, and small scale agriculture.
Another strategy in water conservation is protecting groundwater resources. When precipitation occurs, some infiltrates the soil and goes underground. Water in this saturation zone is called groundwater. Contamination of groundwater causes the groundwater water supply to not be able to be used as resource of fresh drinking water and the natural regeneration of contaminated groundwater can takes years to replenish. Some examples of potential sources of groundwater contamination include storage tanks, septic systems, uncontrolled hazardous waste, landfills, atmospheric contaminants, chemicals, and road salts. Contamination of groundwater decreases the replenishment of available freshwater so taking preventative measures by protecting groundwater resources from contamination is an important aspect of water conservation.
An additional strategy to water conservation is practicing sustainable methods of utilizing groundwater resources. Groundwater flows due to gravity and eventually discharges into streams. Excess pumping of groundwater leads to a decrease in groundwater levels and if continued it can exhaust the resource. Ground and surface waters are connected and overuse of groundwater can reduce and, in extreme examples, diminish the water supply of lakes, rivers, and streams. In coastal regions, over pumping groundwater can increase saltwater intrusion which results in the contamination of groundwater water supply. Sustainable use of groundwater is essential in water conservation.
A fundamental component to water conservation strategy is communication and education outreach of different water programs. Developing communication that educates science to land managers, policy makers, farmers, and the general public is another important strategy utilized in water conservation. Communication of the science of how water systems work is an important aspect when creating a management plan to conserve that system and is often used for ensuring the right management plan to be put into action.
Effects of water pollution
Today, it is hardly possible to use near-surface groundwater for drinking water, as the Drinking Water Ordinance stipulates that, among other things, no more than 50 mg nitrate / liter may be detectable in drinking water. Therefore, ever deeper groundwater resources are used for drinking water.
Measures for water conservation
The water purification is carried out with the aim to reduce the influence of human use of the waters and their surroundings to a tolerable level. In the area of the European Union, the Water Framework Directive defines the achievement of a good ecological status as the objective of water quality and thus of water protection. At the national level, this task is above all water law. But other laws in the field of environmental law have the goal of water protection, in Germany it is mainly the Federal Immission Control Act, the industrial equipment, the application of the state of the artprescribes. The state of the art is synonymous with " best available techniques " (BAT) published by the European Union in BREFs and binding " BAT conclusions ".
Measures of water pollution control can be:
Adapted agricultural management, for example by erosion prevention, manure analysis and fertilizing - and pesticides minimizing, reducing nutrient overhangs by undersowing of red fescue on maize fields
Avoidance of water pollution by avoiding the use of water or environmentally hazardous substances.
Reduction of the entry of substances hazardous to the aquatic environment and the environment due to their retention at the place of collection (eg during operation by filtering, flocculation, biological wastewater treatment, activated carbon, etc.).
Measures for wastewater discharge and treatment in a wastewater treatment plant.
Proper waste disposal.
Prevention and control of accidents and incidents, for example by proper storage of substances hazardous to water and the environment and retention of extinguishing water.
Help with cleansing of waters
Observe protected areas for plants and animals at the lake / river
Keep the banks and embankments clean
Do not waste water
If possible use rainwater
Use environmentally friendly detergents and cleaners
Do not tip oil or fat into the water
The monitoring of the status of waters and the development of waters is called water monitoring.
General objectives for groundwater protection
Groundwater is an essential element of the natural balance. It is part of the water cycle and fulfills important ecological functions. Groundwater is also the most important drinking water resource in Germany. The groundwater must therefore be largely protected against contamination. For groundwater protection there are therefore the following general objectives:
The groundwater shall be protected against impurities or other adverse changes in its properties and preserved in its natural state.
The management of groundwater must be in harmony with the natural environment.
Groundwater is to be protected as a precautionary measure and comprehensively.
Quality standard is its anthropogen largely unaffected nature.
Social solutions
Water conservation programs involved in social solutions are typically initiated at the local level, by either municipal water utilities or regional governments. Common strategies include public outreach campaigns, tiered water rates (charging progressively higher prices as water use increases), or restrictions on outdoor water use such as lawn watering and car washing. Cities in dry climates often require or encourage the installation of xeriscaping or natural landscaping in new homes to reduce outdoor water usage. Most urban outdoor water use in California is residential, illustrating a reason for outreach to households as well as businesses.
One fundamental conservation goal is universal metering. The prevalence of residential water metering varies significantly worldwide. Recent studies have estimated that water supplies are metered in less than 30% of UK households, and about 61% of urban Canadian homes (as of 2001). Although individual water meters have often been considered impractical in homes with private wells or in multifamily buildings, the U.S. Environmental Protection Agency estimates that metering alone can reduce consumption by 20 to 40 percent. In addition to raising consumer awareness of their water use, metering is also an important way to identify and localize water leakage. Water metering would benefit society, in the long run, it is proven that water metering increases the efficiency of the entire water system, as well as help unnecessary expenses for individuals for years to come. One would be unable to waste water unless they are willing to pay the extra charges, this way the water department would be able to monitor water usage by the public, domestic and manufacturing services.
Some researchers have suggested that water conservation efforts should be primarily directed at farmers, in light of the fact that crop irrigation accounts for 70% of the world's fresh water use. The agricultural sector of most countries is important both economically and politically, and water subsidies are common. Conservation advocates have urged removal of all subsidies to force farmers to grow more water-efficient crops and adopt less wasteful irrigation techniques.[citation needed]
New technology poses a few new options for consumers, features such as full flush and half flush when using a toilet are trying to make a difference in water consumption and waste. Also available are modern shower heads that help reduce wasting water: Old shower heads are said to use 5-10 gallons per minute, while new fixtures available are said to use 2.5 gallons per minute and offer equal water coverage.[citation needed]
Household applications
The Home Water Works website contains useful information on household water conservation. Contrary to the popular view that the most effective way to save water is to curtail water-using behavior (e.g., by taking shorter showers), experts suggest the most efficient way is replacing toilets and retrofitting washers; as demonstrated by two household end use logging studies in the U.S.
Water-saving technology for the home includes:
Low-flow shower heads sometimes called energy-efficient shower heads as they also use less energy
Low-flush toilets and composting toilets. These have a dramatic impact in the developed world, as conventional Western toilets use large volumes of water
Dual flush toilets created by Caroma includes two buttons or handles to flush different levels of water. Dual flush toilets use up to 67% less water than conventional toilets
Faucet aerators, which break water flow into fine droplets to maintain "wetting effectiveness" while using less water. An additional benefit is that they reduce splashing while washing hands and dishes
Raw water flushing where toilets use sea water or non-purified water
Wastewater reuse or recycling systems, allowing:
Reuse of graywater for flushing toilets or watering gardens
Recycling of wastewater through purification at a water treatment plant. See also Wastewater - Reuse
Rainwater harvesting
High-efficiency clothes washers
Weather-based irrigation controllers
Garden hose nozzles that shut off the water when it is not being used, instead of letting a hose run.
Low flow taps in wash basins
Swimming pool covers that reduce evaporation and can warm pool water to reduce water, energy and chemical costs.
Automatic faucet is a water conservation faucet that eliminates water waste at the faucet. It automates the use of faucets without the use of hands.
Commercial applications
Many water-saving devices (such as low-flush toilets) that are useful in homes can also be useful for business water saving. Other water-saving technology for businesses includes:
Waterless urinals
Waterless car washes
Infrared or foot-operated taps, which can save water by using short bursts of water for rinsing in a kitchen or bathroom
Pressurized waterbrooms, which can be used instead of a hose to clean sidewalks
X-ray film processor re-circulation systems
Cooling tower conductivity controllers
Water-saving steam sterilizers, for use in hospitals and health care facilities
Rain water harvesting
Water to Water heat exchangers.
Agricultural applications
For crop irrigation, optimal water efficiency means minimizing losses due to evaporation, runoff or subsurface drainage while maximizing production. An evaporation pan in combination with specific crop correction factors can be used to determine how much water is needed to satisfy plant requirements. Flood irrigation, the oldest and most common type, is often very uneven in distribution, as parts of a field may receive excess water in order to deliver sufficient quantities to other parts. Overhead irrigation, using center-pivot or lateral-moving sprinklers, has the potential for a much more equal and controlled distribution pattern. Drip irrigation is the most expensive and least-used type, but offers the ability to deliver water to plant roots with minimal losses. However, drip irrigation is increasingly affordable, especially for the home gardener and in light of rising water rates. Using drip irrigation methods can save up to 30,000 gallons of water per year when replacing irrigation systems that spray in all directions. There are also cheap effective methods similar to drip irrigation such as the use of soaking hoses that can even be submerged in the growing medium to eliminate evaporation.
As changing irrigation systems can be a costly undertaking, conservation efforts often concentrate on maximizing the efficiency of the existing system. This may include chiseling compacted soils, creating furrow dikes to prevent runoff, and using soil moisture and rainfall sensors to optimize irrigation schedules. Usually large gains in efficiency are possible through measurement and more effective management of the existing irrigation system. The 2011 UNEP Green Economy Report notes that "mproved soil organic matter from the use of green manures, mulching, and recycling of crop residues and animal manure increases the water holding capacity of soils and their ability to absorb water during torrential rains", which is a way to optimize the use of rainfall and irrigation during dry periods in the season.
Water Reuse
Water shortage has become an increasingly difficult problem to manage. More than 40% of the world's population live in a region where the demand for water exceeds its supply. The imbalance between supply and demand, along with persisting issues such as climate change and exponential population growth, has made water reuse a necessary method for conserving water. There are a variety of methods used in the treatment of waste water to ensure that it is safe to use for irrigation of food crops and/or drinking water.
Seawater desalination requires more energy than the desalination of fresh water. Despite this, many seawater desalination plants have been built in response to water shortages around the world. This makes it necessary to evaluate the impacts of seawater desalination and to find ways to improve desalination technology. Current research involves the use of experiments to determine the most effective and least energy intensive methods of desalination.
Sand filtration is another method used to treat water. Recent studies show that sand filtration needs further improvements, but it is approaching optimization with its effectiveness at removing pathogens from water. Sand filtration is very effective at removing protozoa and bacteria, but struggles with removing viruses. Large-scale sand filtration facilities also require large surface areas to accommodate them.
The removal of pathogens from recycled water is of high priority because wastewater always contains pathogens capable of infecting humans. The levels of pathogenic viruses have to be reduced to a certain level in order for recycled water to not pose a threat to human populations. Further research is necessary to determine more accurate methods of assessing the level of pathogenic viruses in treated wastewater.
Wasting of water
Wasting of water (also called "water waste" in the U.S.) is the flip side of water conservation and, in household applications, it means causing or permitting discharge of water without any practical purpose. Inefficient water use is also considered wasteful. By EPA estimate, household leaks in the U.S. can waste approximately 900 billion gallons (3.4 billion cubic meters) of water annually nationwide. Generally, water management agencies are reluctant or unwilling to give a concrete definition to the somewhat fuzzy concept of water waste. However, definition of water waste is often given in local drought emergency ordinances. One example refers to any acts or omissions, whether willful or negligent, that are “causing or permitting water to leak, discharge, flow or run to waste into any gutter, sanitary sewer, watercourse or public or private storm drain, or to any adjacent property, from any tap, hose, faucet, pipe, sprinkler, pond, pool, waterway, fountain or nozzle.”. In this example, the city code also clarifies that “in the case of washing, “discharge,” “flow” or “run to waste” means that water in excess of that necessary to wash, wet or clean the dirty or dusty object, such as an automobile, sidewalk, or parking area, flows to waste. Water utilities (and other media sources) often provide listings of wasteful water-use practices and prohibitions of wasteful uses. Examples include utilities in San Antonio, Texas. Las Vegas, Nevada, California Water Service company in California, and City of San Diego, California. The City of Palo Alto in California enforces permanent water use restrictions on wasteful practices such as leaks, runoff, irrigating during and immediately after rainfall, and use of potable water when non-potable water is available. Similar restrictions are in effect in the State of Victoria, Australia. Temporary water use bans (also known as "hosepipe bans") are used in England, Scotland, Wales and Northern Ireland.
Strictly speaking, water that is discharged into the sewer, or directly to the environment is not wasted or lost. It remains within the hydrologic cycle and returns to the land surface and surface water bodies as precipitation. However, in many cases, the source of the water is at a significant distance from the return point and may be in a different catchment. The separation between extraction point and return point can represent significant environmental degradation in the watercourse and riparian strip. What is "wasted" is the community's supply of water that was captured, stored, transported and treated to drinking quality standards. Efficient use of water saves the expense of water supply provision and leaves more fresh water in lakes, rivers and aquifers for other users and also for supporting ecosystems. A concept that is closely related to water wasting is "water-use efficiency." Water use is considered inefficient if the same purpose of its use can be accomplished with less water. Technical efficiency derives from engineering practice where it is typically used to describe the ratio of output to input and is useful in comparing various products and processes. For example, one showerhead would be considered more efficient than another if it could accomplish the same purpose (i.e., of showering) by using less water or other inputs (e.g., lower water pressure). However, the technical efficiency concept is not useful in making decisions of investing money (or resources) in water conservation measures unless the inputs and outputs are measured in value terms. This expression of efficiency is referred to as economic efficiency and is incorporated into the concept of water conservation.
Importance of water protection
In the 1970s, the Rhine near Düsseldorf was a body of water with severe organic pollution. The result was a low oxygen content. The Neckar near Ludwigsburg also had an enormous O 2 deficit and a high concentration of sewage fungi. The Rhine and Neckar rivers were considered "sewers of the nation" in the 1970s. The waters of the Rhine and Neckar were awarded the water quality class IV in the late 1970s, while today both rivers and most other rivers in Germany have almost drinking water quality (quality class II).
Particularly dramatic was the pollution of the waters in the GDR. The GDR had a total of 90,000 kilometers of rivers and streams. Due to their organic, hygienic and saline load, 46 percent of the 11,000 kilometers in 1990 were no longer suitable for bathing, no longer for simple treatment in industry and certainly not for drinking water supply. After the reunification, the water quality of the rivers in the west was reached by the construction of new sewage treatment plants and the ending of particularly environmentally harmful production processes.
Today, the permanent monitoring programs of river monitoring in Baden-Württemberg comprise careful biological-physical and physical-chemical investigations. They permanently monitor the water quality of running waters and stagnant waters and grade these with so-called water quality classes.
Source from Wikipedia
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