An aquifer is an underground layer of water-bearing material, consisting of permeable or fractured rock, or of unconsolidated materials. Aquifers vary greatly in their characteristics. The study of water flow in aquifers and the characterization of aquifers is called hydrogeology. Related terms include aquitard, which is a bed of low permeability along an aquifer, and aquiclude, which is a solid, impermeable area underlying or overlying an aquifer, the pressure of which could lead to the formation of a confined aquifer. The classification of aquifers is as follows: Saturated versus unsaturated; aquifers versus aquitards; confined versus unconfined; isotropic versus anisotropic; porous, karst, or fractured; transboundary aquifer.
The Ogallala Aquifer is a shallow water table aquifer surrounded by sand, silt, clay, and gravel located beneath the Great Plains in the United States. As one of the world's largest aquifers, it underlies an area of approximately 174,000 sq mi (450,000 km2) in portions of eight states. It was named in 1898 by geologist N. H. Darton from its type locality near the town of Ogallala, Nebraska. The aquifer is part of the High Plains Aquifer System, and resides in the Ogallala Formation, which is the principal geologic unit underlying 80% of the High Plains.
Resource depletion is the consumption of a resource faster than it can be replenished. Natural resources are commonly divided between renewable resources and non-renewable resources. The use of either of these forms of resources beyond their rate of replacement is considered to be resource depletion. The value of a resource is a direct result of its availability in nature and the cost of extracting the resource. The more a resource is depleted the more the value of the resource increases. There are several types of resource depletion, including but not limited to: mining for fossil fuels and minerals, deforestation, pollution or contamination of resources, wetland and ecosystem degradation, soil erosion, overconsumption, aquifer depletion, and the excessive or unnecessary use of resources. Resource depletion is most commonly used in reference to farming, fishing, mining, water usage, and the consumption of fossil fuels. Depletion of wildlife populations is called defaunation.
Groundwater is the water present beneath Earth's surface in rock and soil pore spaces and in the fractures of rock formations. About 30 percent of all readily available fresh water in the world is groundwater. A unit of rock or an unconsolidated deposit is called an aquifer when it can yield a usable quantity of water. The depth at which soil pore spaces or fractures and voids in rock become completely saturated with water is called the water table. Groundwater is recharged from the surface; it may discharge from the surface naturally at springs and seeps, and can form oases or wetlands. Groundwater is also often withdrawn for agricultural, municipal, and industrial use by constructing and operating extraction wells. The study of the distribution and movement of groundwater is hydrogeology, also called groundwater hydrology.
The exploitation of natural resources describes using natural resources, often non-renewable or limited, for economic growth or development. Environmental degradation, human insecurity, and social conflict frequently accompany natural resource exploitation. The impacts of the depletion of natural resources include the decline of economic growth in local areas; however, the abundance of natural resources does not always correlate with a country's material prosperity. Many resource-rich countries, especially in the Global South, face distributional conflicts, where local bureaucracies mismanage or disagree on how resources should be used. Foreign industries also contribute to resource exploitation, where raw materials are outsourced from developing countries, with the local communities receiving little profit from the exchange. This is often accompanied by negative effects of economic growth around the affected areas such as inequality and pollution
A water supply network or water supply system is a system of engineered hydrologic and hydraulic components that provide water supply. A water supply system typically includes the following:
- A drainage basin
- A raw water collection point where the water accumulates, such as a lake, a river, or groundwater from an underground aquifer. Raw water may be transferred using uncovered ground-level aqueducts, covered tunnels, or underground water pipes to water purification facilities.
- Water purification facilities. Treated water is transferred using water pipes.
- Water storage facilities such as reservoirs, water tanks, or water towers. Smaller water systems may store the water in cisterns or pressure vessels. Tall buildings may also need to store water locally in pressure vessels in order for the water to reach the upper floors.
- Additional water pressurizing components such as pumping stations may need to be situated at the outlet of underground or aboveground reservoirs or cisterns.
- A pipe network for distribution of water to consumers and other usage points
- Connections to the sewers are generally found downstream of the water consumers, but the sewer system is considered to be a separate system, rather than part of the water supply system.
Environmental technology (envirotech) is the use of engineering and technological approaches to understand and address issues that affect the environment with the aim of fostering environmental improvement. It involves the application of science and technology in the process of addressing environmental challenges through environmental conservation and the mitigation of human impact to the environment.
Sustainable urban infrastructure expands on the concept of urban infrastructure by adding the sustainability element with the expectation of improved and more resilient urban development. In the construction and physical and organizational structures that enable cities to function, sustainability also aims to meet the needs of the present generation without compromising the capabilities of the future generations.
Overdrafting is the process of extracting groundwater beyond the equilibrium yield of an aquifer. Groundwater is one of the largest sources of fresh water and is found underground. The primary cause of groundwater depletion is the excessive pumping of groundwater up from underground aquifers. Insufficient recharge can lead to depletion, reducing the usefulness of the aquifer for humans. Depletion can also have impacts on the environment around the aquifer, such as soil compression and land subsidence, local climatic change, soil chemistry changes, and other deterioration of the local environment.
Water scarcity is the lack of fresh water resources to meet the standard water demand. There are two types of water scarcity. One is physical. The other is economic water scarcity. Physical water scarcity is where there is not enough water to meet all demands. This includes water needed for ecosystems to function. Regions with a desert climate often face physical water scarcity. Central Asia, West Asia, and North Africa are examples of arid areas. Economic water scarcity results from a lack of investment in infrastructure or technology to draw water from rivers, aquifers, or other water sources. It also results from weak human capacity to meet water demand. Many people in Sub-Saharan Africa are living with economic water scarcity.
This is a glossary of environmental science.
Slingshot is a water purification device created by inventor Dean Kamen. Powered by a Stirling engine running on a combustible fuel source, it claims to be able to produce drinking water from almost any source by means of vapor compression distillation, requires no filters, and can operate using cow dung as fuel.
Water resources are natural resources of water that are potentially useful for humans, for example as a source of drinking water supply or irrigation water. These resources can be either freshwater from natural sources, or water produced artificially from other sources, such as from reclaimed water (wastewater) or desalinated water (seawater). 97% of the water on Earth is salt water and only three percent is fresh water; slightly over two-thirds of this is frozen in glaciers and polar ice caps. The remaining unfrozen freshwater is found mainly as groundwater, with only a small fraction present above ground or in the air. Natural sources of fresh water include surface water, under river flow, groundwater and frozen water. People use water resources for agricultural, industrial and household activities.
A water footprint shows the extent of water use in relation to consumption by people. The water footprint of an individual, community, or business is defined as the total volume of fresh water used to produce the goods and services consumed by the individual or community or produced by the business. Water use is measured in water volume consumed (evaporated) and/or polluted per unit of time. A water footprint can be calculated for any well-defined group of consumers or producers, for a single process or for any product or service.
The aim of water security is to make the most of water's benefits for humans and ecosystems. The second aim is to limit the risks of destructive impacts of water to an acceptable level. These risks include for example too much water (flood), too little water or poor quality (polluted) water. People who live with a high level of water security always have access to "an acceptable quantity and quality of water for health, livelihoods and production". For example, access to water, sanitation and hygiene services is one part of water security. Some organizations use the term water security more narrowly for water supply aspects only.
Micro-sustainability is the portion of sustainability centered around small scale environmental measures that ultimately affect the environment through a larger cumulative impact. Micro-sustainability centers on individual efforts, behavior modification, education and creating attitudinal changes, which result in an environmentally conscious individual. Micro-sustainability encourages sustainable changes through "change agents"—individuals who foster positive environmental action locally and inside their sphere of influence. Examples of micro-sustainability include recycling, power saving by turning off unused lights, programming thermostats for efficient use of energy, reducing water usage, changing commuting habits to use less fossil fuels or modifying buying habits to reduce consumption and waste. The emphasis of micro-sustainability is on an individual's actions, rather than organizational or institutional practices at the systemic level. These small local level actions have immediate community benefits if undertaken on a widespread scale and if imitated, they can have a cumulative broad impact.
Sustainable products are products either sustainably sourced, manufactured or processed and provide environmental, social, and economic benefits while protecting public health and the environment throughout their whole life cycle, from the extraction of raw materials to the final disposal.
Water issues in developing countries include scarcity of drinking water, poor infrastructure for water and sanitation access, water pollution, and low levels of water security. Over one billion people in developing countries have inadequate access to clean water. The main barriers to addressing water problems in developing nations include poverty, costs of infrastructure, and poor governance. The effects of climate change on the water cycle can make these problems worse.
Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total dissolved solids. The term excludes seawater and brackish water, but it does include non-salty mineral-rich waters, such as chalybeate springs. Fresh water may encompass frozen and meltwater in ice sheets, ice caps, glaciers, snowfields and icebergs, natural precipitations such as rainfall, snowfall, hail/sleet and graupel, and surface runoffs that form inland bodies of water such as wetlands, ponds, lakes, rivers, streams, as well as groundwater contained in aquifers, subterranean rivers and lakes.
Sustainable Development Goal 12, titled "responsible consumption and production", is one of the 17 Sustainable Development Goals established by the United Nations in 2015. The official wording of SDG 12 is "Ensure sustainable consumption and production patterns". SDG 12 is meant to ensure good use of resources, improve energy efficiency and sustainable infrastructure, provide access to basic services, create green and decent jobs, and ensure a better quality of life for all. SDG 12 has 11 targets to be achieved by at least 2030, and progress towards the targets is measured using 13 indicators.
