Absorption is the incorporation of a substance in one state into another of a different state (e.g. liquids being absorbed by a solid or gases being absorbed by a liquid).
Absorption Chiller
Absorption chillers are refrigerators that use heat energy as an input, rather than mechanical energy. Absorption chillers are useful, where electricity is no available or where there is an easily available source of heat (e.g. sun, hot water). The heat is used to evaporate a liquid to a gas. The gas then moves to the condenser where the heat dissipates and the gas is turned back into a liquid. Then, the cooled liquid is directed into the evaporator, where it turns into a gas and pulls heat from the air. Then the gas moves from the evaporator into the compressor and the process starts again. Sinónimos: Absorption Refrigerator

Accumulation System
An accumulation tank or a continuously fed batch is characterised by an increasing effective reactor volume with time. When the reactor is full and reaction time is over, it is emptied and refilled again as batch reactors. Sinónimos: AC, Accumulation Tank, Fed Batch Reactor
Acetogenesis is the third step of anaerobic digestion. Products from fermentation (organic acids, alcohols) are converted into hydrogen (H2), carbon dioxide (CO2) and acetic acid (CH3COOH). To produce acetic acid, acetogenic bacteria need oxygen and carbon. For this, they use the oxygen solved in the solution or bound-oxygen. Hereby, the acid-producing bacteria create an anaerobic condition, which is essential for the methane-producing microorganisms responsible for the further step of anaerobic digestion which is methanogenesis.

Acidic is an adjective describing the properties of having a pH below 7. Its opposite is alkaline or basic.

Activated Sludge
An activated sludge process refers to a multi-chamber reactor wastewater treatment unit to produce a high-quality effluent. Flocs of microorganism are suspended and mixed with wastewater in an aerated tank. As microorganism grow, they degrade organics and remove nutrients from the sludge and transform it to  water, gas, energy and new cell material. To maintain aerobic conditions and to keep the activated sludge suspended, a continuous and well-timed supply of oxygen is required. An activated sludge unit is normally combined to a primary and tertiary treatment unit. Excess sludge produced through bacteria growth needs also to be removed regularly and treated appropriately.
The process by which molecules of a substance, such as a gas or a liquid, collect on the surface of another substance, such as a solid. The molecules are attracted to the surface but do not enter the solid's minute spaces as in absorption.
Adult Learning
Learning opportunities for adults exist in a variety of settings, ranging from a formal institution to day to day practical learning at work. It is important to acknowledge prior knowledge and experiences of learners, including their ability to recognize their own skills as lifelong learners. Considerations for adult development and learning include biological and psychological development and socio cultural and integrative perspectives on development.
Advanced Facultative Pond
Advanced facultative ponds are the first step in advanced integrated wastewater pond (AIWP) systems. They consist of a conventional facultative pond, containing a digestion pit on its bottom, where solids are trapped and transformed into methane by anaerobic digestion. The surface aerobic layer is about 1 meter deep and helps reducing potential odour problems. Biogas may be collected using a submerged gas canopy and potentially used for energy production. Sinónimos: AFP
Abbreviation: AFP

Advanced Integrated Wastewater Pond
Advanced integrated wastewater pond systems are improved conventional waste stabilisation pond (WSP) systems and are based on a series of four advanced ponds: An advanced facultative pond (AFP) containing a digester pit which functions much like an anaerobic pond integrated into the facultative pond; A high rate pond (HRP), covered by algae which provide oxygen to the water and take up organics and nutrients; An algal settling pond (ASP), where most of the algae produced in the HRP is removed; And finally an maturation pond (MP) for biological and solar disinfection. Sinónimos: Advanced Integrated Pond, AIP, AIWP
Abbreviation: AIWP

Advanced Oxidation Process
The term advanced oxidation processes (AOP), describes a series of processes which are used for the chemical treatment of organic and inorganic pollutants in wastewaters. AOPs are based on the generation of reactive oxygen species (ROS) such as hydroxyl radicals. Generating hydroxyl radicals is possible via various ways such as photocatalytic, electrochemical, sonochemical. Typical AOPs are H2O2/hv, ozone/hv, ozone/H2O2/hv, TiO2/hv, (photo-)Fenton systems and electrochemical processes. Sinónimos: AOP
Abbreviation: AOP

Advanced Wastewater Treatments
Advanced wastewater treatments, in opposition to natural systems require generally highly engineered biological processes, which leads to a reduction in space requirement to achieve similar performances. However, due to the complexity of the process and the high requirements for energy and operation and maintenance, advanced systems inhere a higher risk of technical failure.

Advection Fog
Advection fog is a certain type of fog, that requires a steady wind that moves a fog layer that has formed upwind of a given site.
Fog Research
Advisory Services in Environmental Management
Advisory Services in Environmental Management Sinónimos: ASEM
Abbreviation: ASEM

Advocacy is the action of delivering an argument to gain commitment from political and social leaders and to prepare a society for a particular issue (DE JONG 2003). Advocacy involves the selection and organisation of information to create a convincing argument, and its delivery through various interpersonal and media channels (e.g. public speaking, project visits, petitions, engaging celebrities, radio and newspaper). Influencing and involving important leaders is one of the essentials of advocacy, because political support together with support from community leaders and religious leaders can give a water-related project or campaign a powerful boost (SCHAAP & VAN STEENBERGEN 2001). Sinónimos: Influencing Leaders
Aerated Pond
Aerated ponds are aerobic wastewater treatment ponds (also called waste stabilisation ponds) in which the natural oxygenation is enhanced by mechanical or diffused air injection to achieve high rates of organic degradation and nutrient removal. Aerated ponds can treat almost all wastewater as long as they are biodegradable. Dependent on the type of treatment, a pre-treatment unit is required (e.g. settling, screening, etc.). If completely mixed, the aerated ponds also require a sedimentation step at the output. The process set-up is then in essence similar to activated sludge systems without sludge return. Sinónimos: Aerated Lagoon
Describes biological processes that require oxygen to drive cellular respiration and store energy.
Aerobic Digestion
Aerobic digestion describes the microbial transformation of organic matter into water, heat and CO2 in presence of oxygen. Aerobic digestion is used in wastewater treatment to both organic matter and the volume of sludge. As for anaerobic digestion, process rates increases with increasing temperature. Aerobic sludge digestion facilities may be designed for batch or continuous flow operations and the process results in approximately 50% reduction in solids content for typical municipal wastewaters. Typical wastewater treatments, using aerobic digestion are activated sludge systems, trickling filters, aerobic ponds etc.

Aerobic Pond
A lagoon that forms the third treatment stage in waste stabilization ponds (WSP). It is a shallow pond with large surface area to enable light penetration and oxygenation by wind mixing. The effluent is generally free of pathogens but rich in nutrients and can be reused for fertigation or aquaculture. Sinónimos: Maturation Pond, MP, Polishing Pond
Aerobic Wastewater Treatment
Aerobic wastewater treatments use aerobic microorganisms to transform pollution into a variety of oxidized end products, carbon dioxide, and metabolized biomass. Generally, aerobic wastewater treatment is faster than anaerobic treatments but require the supply of oxygen, which can be expensive, and energy consuming.

Aeroponics is the process of growing plants in an air or mist environment without the use of soil or an aggregate medium. The word "aeroponic" is derived from the Greek meanings of "aero" (air) and "ponos" (labour). Unlike hydroponics, which uses water as a growing medium and essential minerals to sustain plant growth, aeroponics is conducted without a growing medium. Aeroponic equipment involves the use of sprayers, misters, foggers, or other devices to create a fine mist of water to deliver nutrients to plant roots. Because water is used in aeroponics to transmit nutrients, it is sometimes considered a type of hydroponics.
Anaerobic microorganisms, which are not sensitive to oxygen and can growth both in its absence and in its presence.

African Development Bank
African Development Bank Sinónimos: AfDB
Abbreviation: AfDB

African Development Fund
African Development Fund Sinónimos: ADF
Abbreviation: ADF

African Ministers Conference On Water
African Ministers Conference On Water Sinónimos: AMCOW
Abbreviation: AMCOW

African Union
African Union Sinónimos: AU
Abbreviation: AU

Agenda 21
The first UN Conference on Environment and Development in 1992 adopted an agenda for environment and development in the 21st Century. This “Agenda 21: A Programme of Action for Sustainable Development” reaffirmed that sustainable development was delimited by the integration of the economic, social and environmental pillars. The “Agenda 21” is not legally binding, a reason to be criticised by many.
Aggregation formation
Soil particles can stick together and build aggregates where water can be enclosed.

Agricultural Issues
Agricultural issues provides background knowledge that is necessary to understand loop-oriented approaches in the management of water and wastewater - such as soil properties, plant requirements, etc.

Agricultural Wastewater
Agricultural wastewater is all waters that have been used in agriculture and are refused. They are either biodegradable (most often) and can be treated and reused similar to blackwater (e.g. manure from livestock); or they are not biodegradable (e.g. water containing a lot of residues from pesticides etc.) and require an advanced oxidation processes for treatment.

Air Stripping
Air stripping is the transferring of volatile components of a liquid into an air stream. It is a chemical engineering technology used for the purification of groundwater and wastewater containing volatile compounds. Sinónimos: Stripping
Air Stripping
Algae Settling Pond
Algae Settling Pond follow the high rate algae pond in a advanced integrated pond systems. They are designed to settle out algae, and especially important if the water from the high rate algae pond is to be used for crop irrigation. The hydraulic retention time in algae settling ponds are of about two days and the harvested algae can be used as a nitrogen-rich fertilizer, or as protein-rich animal or fish feed (for further cultivation of high protein foodstuffs), modern medicine and even cosmetics for the idle. Sinónimos: ASP
Abbreviation: ASP

Algal Bloom
A rapid increase in the population of algae in an aquatic system, e.g. as a result of an excess of nutrients (particularly phosphorus and nitrogen). As more algae and plants grow, others die. This dead organic matter becomes food for bacteria that decompose it. With more food available, the bacteria increase in number and use up the dissolved oxygen in the water. When the dissolved oxygen content decreases, many fish and aquatic insects cannot survive. Sinónimos: Marine Bloom, Water Bloom
Algal Bloom
Alkaline is an adjective describing the properties of having a pH greater than 7. It is the opposite of acidic.

The alkalinity measures the capacity of water to neutralise acids. The alkalinity depends on amount of carbonates, bicarbonates, hydroxides, and occasionally borates, silicates and phosphates. Alkalinity stabilises water at pH levels around 7 (neutral). However, high water acidity decreases alkalinity and may cause harmful conditions for aquatic life. Alkalinity is expressed in ppm or mg of calcium carbonate per litre (mg/L CaCO3).
Alluvial River
An alluvial river is a river in which the bed and banks are made up of mobile sediment and/or soil. Alluvial rivers are self-formed, meaning that their channels are shaped by the magnitude and frequency of the floods that they experience, and the ability of these floods to erode, deposit, and transport sediment. As such, alluvial rivers can assume a number of forms based on the properties of their banks; the flows they experience; the local riparian ecology, and the amount, size, and type of sediment that they carry. These forms can be meandering, braiding, wandering and (occasionally) straight.
Colourless astringent compound that is a hydrated double sulphate of aluminium and potassium, used in water purification. Sinónimos: AlK(SO4)
Abbreviation: AlK(SO4)

See ammonium. Sinónimos: NH3
Abbreviation: NH3

Ammonia nitrogen (NH4-N) is found in aqueous solutions as ammonium ion (NH4+) or ammonia gas (NH3), depending on the pH and the temperature of the solution. It is a bioavailable form of the macronutrient nitrogen and found in many fertilisers. It is also the result of the decomposition of organic nitrogen in wastewaters. At high pH, NH3 is predominant. NH3 is volatile, colourless and has a pungent odour. If it escapes to the atmosphere, it can travel large distances and resettle with the rain, what can lead to overfertilisation (eutrophication) and acidification of ecosystem. Sinónimos: NH4+
Abbreviation: NH4+
Wastewater Engineering, Treatment and Reuse
Describes biological processes that that occur in the absence of any form of oxygen available for metabolic activity. Anaerobic processes are either hindered, or halted by the presence of oxygen.
Anaerobic Ammonium Oxidation
ANAMMOX stands for Anaerobic Ammonium Oxidation. It is quite a new process, which combines ammonia and nitrite into dinitrogen gas directly instead of passing through a two stage process of aerobic nitrification and anaerobic denitrification. Compared to conventional nitrification/denitrification in activated sludge systems, ANAMMOX eliminates the necessity of an organic carbon source for nitrification, reduces energy demand for aeration and has a smaller production of excess sludge and lower CO2 emissions. Sinónimos: ANAMMOX
Anaerobic Baffled Reactor
An anaerobic baffled reactor (ABR) is an improved Septic Tank with a series of baffles under which the wastewater is forced to flow. The increased contact time with the active biomass (sludge) results in increased retention and anaerobic degradation of suspended and dissolved organic pollutants. ABRs are robust and can treat a wide range of wastewater, but both remaining sludge and effluents still need further treatment in order to be reused or discharged properly. Sinónimos: ABR
Anaerobic Biogas Digester
A biogas reactor or anaerobic digester is an anaerobic treatment technology that uses organic material (e.g. wastewater, kitchen wastes, etc.) and produces (a) a digested slurry (digestate) that can be used as a fertilizer and (b) biogas that can be used for energy. Sinónimos: Anaerobic Digester, Biogas Reactor
Anaerobic Biogas Settler
Anaerobic biogas settlers are air-tight reactors used for the pre-settlement of municipal wastewaters and the conversion of the settled sludge into biogas via anaerobic digestion. Biogas is recovered and can be transformed into heat, light or any other energy. The reactors are round or square - much like a septic tank, but with biogas collection. As the wastewater flows into the tank, organic solids start to settle to the ground. The liquid phase continuous to further treatment steps after a relatively short hydraulic retention time, while the sludge is kept in the tank for several months to years (long sludge retention time). The remaining slurry is almost pathogen free and can be used as soil amendment (optionally after an aerobic composting post-treatment or drying/humification in a sludge drying bed). Biogas settlers are most often used at community or institutional level as first treatment step of a decentralized wastewater treatment systems (DEWATS) for the pre-treatment of biodegradable domestic or industrial wastewaters. Sinónimos: Biogas Settler

Anaerobic Digestion
The degradation and stabilization of organic compounds by microorganisms in the absence of oxygen, leading to production of biogas.
Anaerobic Filter
An anaerobic filter is a fixed-bed biological reactor with one or more filtration chambers in series. As wastewater flows through the filter, particles are trapped and organic matter is degraded by the active biomass that is attached to the surface of the filter material. Anaerobic filters are similar to septic tank, with the difference, that wastewater, once entered into the tank must flow downwards (anaerobic downflow filter) or upwards through a filter media (anaerobic upflow filter). Anaerobic filters are used as secondary treatment in household-level or decentralised wastewater treatment systems. As for any anaerobic digestion process, biogas can be recovered and transformed to energy or light. Sinónimos: AF
Anaerobic Pond
A lagoon that forms the first treatment stage in waste stabilization ponds. It is a rather deep pond (3 to 5 m) with small surface area. As wastewater flows in, suspended solids settle to the ground and degraded by anaerobic microorganism. As for any anaerobic digestion process, biogas can be recovered and transformed to energy or light. Sinónimos: AP
Anaerobic Wastewater Treatment Process
Anaerobic Wastewater Treatment processes are based on the treatment of waste and wastewater by a process called anaerobic digestion. During anaerobic digestion, the organic matter in the waste and wastewaters is transformed to biogas, a mix of methane (CH4) and carbon dioxide (CO2) and a nutrient rich sludge. Biogas can be transformed into heat or power and has therefore a large potential as a renewable energy source. The nutrient-rich sludge can be composted and used as fertilising soil amendment in agriculture. Typical biogas sanitation technologies are biogas settlers, upflow anaerobic sludge blanket (UASB) reactors, anaerobic baffled reactors (ABRs) and anaerobic filters for municipal wastewaters; and biogas reactors (batch, fed-batch PFR or CSTR) for the treatment of slurries and solid organic wastes from agriculture and industry.

Anal Cleansing Water
Anal Cleansing Water is water used to cleanse oneself after defecating and/or urinating; it is generated by those who use water, rather than dry material, for anal cleansing. The volume of water used per cleaning typically ranges from 0.5 L to 3 L.
Anammox Bacteria
The causative organism, which was responsible for the Anammox reaction was named Candidatus Brocadia anammoxidans. This organism is a member of the planctomycetes and therefore lacks peptidoglycan in its cell wall, divides by budding, and has a compartmentalised cytoplasm. Candidatus Brocadia anammoxidans is able to anaerobically oxidise ammonium and nitrite to nitrogen gas. The key enzyme involved in this reaction, hydroxylamine oxidoreductase, is located in an organelle-like structure called an anammoxosome. The ability to oxidise ammonium anaerobically makes Candidatus Brocadia anammoxidans potentially useful for reducing, or eliminating, ammonium from wastewater. Sinónimos: Candidatus Brocadia anammoxidans
Anoxic describes processes, which occur in the absence of molecular gaseous oxygen, but other forms of oxygen are still present (in opposite to anaerobic, which means that there is no oxygen at all) and used for the respiration of microorganism. Anoxic conditions are often found at the interface between aerobic and anaerobic environments (e.g. in trickling filters or in facultative ponds).The biological conversion of nitrate is to nitrogen gas is anoxic. This process is also known as denitrification.
Application of Pit Humus and Compost
Compost is the soil-like substance resulting from the controlled aerobic degradation of organics. Pit humus is the term used to describe the material removed from a double pit technology (S.4, S.5 or S.6) because it is produced passively underground and has a slightly different composition than compost. Both products can be used as soil conditioners.
Application of Sludge
Depending on the treatment type and quality, digested or stabilized sludge can be applied to public or private lands for landscaping or agriculture.
To protect the immediate surroundings of a well, a concrete slab is installed around the water extraction point. Sinónimos: Well cover

Aqua Privy
The aqua privy is a simplified variation of the septic tank. It is a simple storage and settling tank immediately under the latrine floor. Excreta drop directly into the tank through a pipe. Te bottom of the pipe is submerged in the liquid in the tank, forming a water seal to prevent escape of flies, mosquitoes and smell. Effluent usually infiltrates into the ground through a soak pit. Accumulated solids (sludge) must be removed frequently and enough water must be added to compensate for evaporation and leakage losses (in order to maintain the water seal).

Aquaculture refers to the controlled cultivation of aquatic plants and animals such as fish, crustaceans and aquatic plants. Aquaculture can be part of an integrated sanitation system making use of nutrients and heat from pre-treated wastewater.
Aquaponics is the symbiotic cultivation of plants and aquatic animals in a recirculating environment. Aquaponic comes from the two words aquaculture and hydroponic. The main aim of such systems is the recycling of the nutrients contained in the water from aquatic animal effluent. The system contain of to interlinked compartement, one for growing plants and one for growing aquatic animals. The plants take up the nutrients, allowing them to grow and reducing or eliminating the water's toxicity for the aquatic animal. Thus the water can be recirculated back to the animal pond where it will be charged again by nutrients.

An aquifer is a wet underground layer of water-bearing permeable rock or unconsolidated materials (gravel, sand, or silt) from which groundwater can usefully be extracted using a water well.
Arborloo is a type of composting toilet. Combining a user interface and a storage and composting pit. The shallow pit is filled with excreta and soil/ash and then covered with soil. The decommissioned full pit poses no immediate health risk and the contents will degrade naturally over time. Alternatively, a tree planted on top of the nutrient-rich pit will vigorously grow. Sinónimos: Fill and Cover
Arid climate is characterised by high evaporation and low precipitation. This climate is typical for desert or semi-desert as well as big continental areas surrounded by mountains.
Pentavalent Arsenic Sinónimos: As(V)
Abbreviation: As(V)

Trivalent Arsenic Sinónimos: As(III)
Abbreviation: As(III)

Artesian Spring
Artesian springs occur when water is trapped between impervious layers and is forced to the surface under pressure. At these springs, the water comes out of the ground vertically.
Spring Catchment
Artificial Fertiliser
Artificial fertilisers are plant nutrients produced through chemical processes to nurture soil and foster plant growth. Artificial fertilisers mainly consist of plant macronutrients such as Nitrogen, Potassium, Phosphorus and Sulphur, but lack other essential substances (micronutrients). Artificial fertiliser are able to improve the chemical properties of soils, but as they contain no organic substances, they are not able to counter the loss of organic substance through harvesting, which is important for soil structure. On the other hand, organic fertilisers produced out of biodegradable waste – such as e.g. kitchen residues, manure and other organic waste – are complete fertilisers that are able to improve both physical and chemical properties of the soil, and that are normally more balanced in their composition, containing macro- and micronutrients.

Artificial Groundwater Recharge
Artificial recharge is the planned, man-made increase of groundwater levels. By improving its natural replenishment capacities and percolation from surface waters into aquifers, the amount of groundwater available for abstraction is increased. Treated effluent and/or stormwater is discharged into aquifers either directly or after pre-treatment (e.g. wastewater stabilisation ponds or constructed wetlands). This is particularly useful in areas where water and groundwater resources are heavily utilised and acute problems with dropping watersheds, soil salinisation, saltwater intrusion in coastal areas or water scarcity in general exist. Sinónimos: Groundwater Recharge

Automated irrigation
An automated irrigation system refers to the operation of the system with no or just a minimum of manual intervention. Almost every irrigation system can be automated with the help of timers, sensors, computers, or mechanical appliances.

Automatic Surge Flow and Gravitational Tank Irrigation System
This is an intermittent gravity-flow irrigation system consisting of a storage tank equipped with one or more siphons. The water in the tank flows to the field because of the siphon effect. As soon as the tank is empty, the flow stops. For the next irrigation process, the tank has to be filled-up to restart the siphon effect again. To learn more about possible siphon designs see VORTECH (2009).
Awareness Raising
With Awareness Raising Tools, you try to influence social norms, attitudes and values of people so they will change their behaviour because they are convinced that they are doing the right thing and their actions are in line with their personal values. Different types of information, education and communication (IEC) instruments can be used to initiate behavioural change and to stimulate social pressure towards sound and sustainable policies.

Awareness Raising for Demand Creation
Awareness raising includes an array of different technologies to make people aware of a problem, a new approach, a solution etc.

Backflush Valve
Backflush valves are 3-way hydraulically operated diaphragm valves commonly used in filtration applications. The valve has a common outlet connected to the filter inlet and two other outlets, one connected to the water inlet manifold, the other to the drain manifold. The valve can be set in one of two positions: (1) Filtration mode allows flow from the inlet manifold into the filter; and (2) Flushing mode closes the filter connection to the inlet manifold and connects the filter inlet to the drain outlet resulting in reversal flow of filtered water from neighbouring filters through the filter. Sinónimos: Backwash Valve
The background section contains essential background knowledge on water management and sanitation, covering areas such as health & hygiene, frameworks, economic aspects, environmental aspects, etc.

One of the best ways to clean a water system’s filter is to backwash it, meaning reversing the flow and increasing the velocity at which water passes back through the filter. This, in effect, blasts the clogged particles off of the filter. Although every filter is unique, the principles of backwashing are similar for all of them. The disadvantage with backwashing is that it requires energy-driven pumps and the backwash water and sludge has to be treatment (e.g. in waste stabilisation ponds) before safe discharge or reuse. Sinónimos: Backwashing
Filter Backwashing
Simple, single cell organisms that are found everywhere on earth. They are essential for maintaining life and performing essential “services”, such as composting, aerobic degradation of waste, and digesting food in our intestines. Some types, however, can be pathogenic and cause mild to severe illnesses. Bacteria obtain nutrients from their environment by excreting enzymes that dissolve complex molecules into more simple ones, which can then pass through the cell membrane.
Bank Filtration
Bank filtration is the infiltration of surface water, mostly from a river system, into a groundwater system induced by water abstraction close to the surface water e.g. a river bank. This water abstraction is commonly done by operating wells. As the water flows through the soil, it is filtered and the quality is improved. In the context of developing or newly-industrialised countries, BF may bring relief by replenishing stressed groundwater resources with surface water, which receives treatment while percolating through the soil and is mixed with the groundwater aquifer. Sinónimos: BF
Basic Sanitation
As established by the 2002 World Summit on Sustainable Development (WSSD), basic sanitation means the lowest-cost option for securing sustainable access to safe, hygienic, and convenient facilities and services for excreta and sullage disposal that provide privacy and dignity, while at the same time ensuring a clean and healthful living environment both at home and in the neighbourhood of users.
Basic Services to the Urban Poor
Basic Services to the Urban Poor Sinónimos: BSUP
Abbreviation: BSUP

Basin Irrigation
Basin irrigation is the most common form of surface irrigation, particularly in regions with layouts of small fields. If a field is level in all directions, is encompassed by a dyke to prevent runoff, and provides an undirected flow of water onto the field, it is herein called a basin. Basin irrigation is suitable for many field crops. Paddy rice grows best when its roots are submerged in water making basin irrigation the best method for this type of crop.

Batch Reactor
Batch reactors are reactors with no continuous inflow nor outflow. After the reactor was filled with its content, it is closed for a certain time of reaction. During this time, flow is neither entering nor leaving. After the time of reaction, the now processed liquid or material is removed and replaced by a fresh one and the process cycle can begin again. See also fed batch or accumulating system.
Beneficiary Assessment
Beneficiary Assessment: conversational interviewing and focus group discussions on changes and impacts.
Abbreviation: BA

Bin Composting
Compost can also be made in bags or bins with lateral holes to allow aeration. In order to allow proper aeration, the bin is divided into two sections separated with a grid. Organic waste is put into the top section; the final compost it is removed from the bottom section. Because of the natural draught created in the bin by the grid and the holes, frequent turning of the waste is not required in this method. Sinónimos: In-vessel Composting

Bio-char is a fine-grained charcoal produced from pyrolysis: the slow burning of organic matter in a low- or no-oxygen environment. Bio-char is promoted as a soil additive in order to enhance the soil black carbon content and thus the soil water and nutrient retention capacity.

Biodegradable means that a substance is contained of molecules which can be broken down by biological processes (e.g. by bacteria, fungi, and other microorganisms) without causing any harm to them.

Biological transformation of organic material into more basic compounds and elements (e.g., carbon dioxide, water) by bacteria, fungi, and other microorganisms.
Biodiesel is a renewable, clean-burning diesel replacement made from a diverse mix of feed stocks including recycled cooking oil, soybean oil, and animal fats.
A thin, slimy film of bacteria that adheres to surfaces, which are regularly in contact with water. The structure of biofilms is quite complex consisting of colonies of bacteria and other microorganisms such as yeasts, fungi, and protozoa. Biofilms can be a problem for drinking water supply (pipe fouling). But they are also widely used water purification (e.g. biosand filters, slow sand filtration) or in biological wastewater treatment (e.g. rotating biological contactor, trickling filter). Sinónimos: Schmutzdecke

Biogas is the common name for the mixture of gases released from anaerobic digestion. Biogas is comprised of methane (50 to 75%), carbon dioxide (25 to 50%) and varying quantities of nitrogen, hydrogen sulphide, water vapour and other components. Biogas can be collected and burned for fuel (like propane).
Biogas Combustion
In principal, biogas can be used like other fuel gas. When produced in household-level biogas reactors, it is most suitable for cooking. Additionally, electricity generation is a valuable option when the biogas is produced in large anaerobic digesters.
Biological Oxygen Demand
A measure of the amount of oxygen used by microorganisms to degrade organic matter over time (expressed in mg/L and normally measured over five days as BOD5). It is an indirect measure of the amount of biodegradable organic material present in water or wastewater: the more the organic content, the more oxygen is required to degrade it (high BOD). A high BOD can be caused by high levels of organic pollution or high nitrate levels, which trigger high plant growth. Sinónimos: BOD
Biological Oxygen Demand 5
The biological oxygen demand 5 (BOD5) refers to the biological oxygen demand measures over 5 days at 20 ºC. Sinónimos: BOD5
Abbreviation: BOD5

Biological Treatment
The biological treatment of waste and wastewaters consist in the use of microbial activity (bacteria, funghi and other microorganisms) for the degradation and decomposing of biodegradable pollution. This is in contrast to chemical treatment, which relies on chemicals to transform or remove contaminants from waste.
Biological Wastewater Treatment
Biological wastewater treatment processes are employed to transform dissolved and colloidal pollutants into gases, cell material, and metabolic end products. These processes may occur in the presence or absence of oxygen. In the absence of oxygen (anaerobic process), wastewater materials may be hydrolyzed and the resultant products fermented to produce a variety of alcohols, organic acids, other reduced end products, synthesized cell mass, and gases including carbon dioxide, hydrogen, and methane (biogas). Aerobic processes will generate a variety of oxidized end products, carbon dioxide and metabolized biomass

Biomass refers to plants or animals cultivated using the water and/or nutrients flowing through a sanitation system. It may include fish, insects, vegetables, fruit, forage or other beneficial crops, which can be utilized for food, feed, fibre and fuel production.
Bioremediation is the use of microorganismal metabolism to remove pollutants.

Biosolids, also referred to as treated sludge, is a term used to denote the by-product of wastewater treatment. Biosolids are generally rich in organic matter and nutrients and it can therefore be used as a soil amendment. Depending of the applied wastewater treatment, the resulting biosolids may require further treatment for the removal of pathogens before reuse. Sinónimos: Treated Sludge; Biosolids

The liquid waste product remaining from sea-salt production; it is highly concentrated in magnesium.

Blackwater is the mixture of urine, faeces and flushwater along with anal cleansing water (if water is used for cleansing) and/or dry cleansing materials. Blackwater contains the pathogens of faeces and the nutrients of urine that are diluted in the flushwater.
Blue Water Footprint
Blue water footprint is a concept used for water footprint accounting. The blue water footprint is an indicator of the consumption of fresh surface or groundwater.
Boiler Feed Water
Boiler feed water is used in various industries for the generation of steam for manufacturing processes. After simple treatment, the water can be reused for various applications. Sinónimos: Boiler Feedwater
Border Irrigation
Border irrigation is a type of surface irrigation where the field is divided into strips separated by border ridges running down the gradient of the field. The area between the ridges is flooded during irrigation. It can be viewed as an extension of basin irrigation to include long rectangular or contoured field shapes, longitudinal but no lateral slope, and free draining or blocked conditions at the lower end. In contrast to basin irrigation bunds are not to contain the water for ponding but to guide it as it flows down the field.

Borehole Latrine
The borehole latrine is an (emergency) excreta disposal system where a borehole (typically 5-10m deep, 40cm in diameter) is combined with a slab and a superstructure. It is an alternative to pit or trench latrines where ground conditions allow it and tools and labour is immediately available locally.
Bottle Irrigation
The bottle is first filled up with water and then placed upside down in the ground next to the plant. Because of its density the water is only released slowly into the ground to reach the roots.

Bottled water
Bottled water is widely available in both industrialised and developing countries. Consumers purchase packaged drinking-water for reasons such as taste, convenience or fashion, but safety and potential health benefits are also important considerations. Bottled water is most commonly sold in glass or disposable plastic bottles. Bottled water also comes in various sizes, from single servings to large carboys holding up to 80 litres. Sinónimos: packaged water, pre-packaged water, Water in bottle

Boundary Kit
Boundary kits isolate individual properties from the main pressure sewer network and can be installed prior to the individual pumping units. This allows for individual properties to connect at a rate that suits the development whilst also allowing fast and simple isolation if required.
Brackish water
Brackish water contains more salt than fresh water and less than salt water. It is commonly found in estuaries, which are the lower courses of rivers where they meet the sea, and aquifers, which are stores of water underground.

Brownwater is the mixture of faeces and flushwater, and does not contain urine. It is generated by urine-diverting flush toilets and, therefore, the volume depends on the volume of the flushwater used. The pathogen and nutrient load of faeces is not reduced, only diluted by the flushwater. Brownwater may also include Anal Cleansing Water (if water is used for cleansing) and/or Dry Cleansing Materials.
Embankment constructed from soil or wadi bed sediments.
Business Model Canvas
The Business Model Canvas is an entrepreneurial tool for describing, designing, challenging, analysing, inventing and pivoting business models. Sinónimos: BMC
Abbreviation: BMC

Abbreviation: Cd

Calcination Kiln
A high temperature oven used to thermally decompose an ore; usually limestone, but also magnesium carbonate.

California Water Environment Association
Founded in 1927, CWEA is a not-for-profit association of 9,000-plus professionals in the wastewater industry. They are committed to keeping California's water clean. They train and certify wastewater professionals, disseminate technical information, and promote sound policies to benefit society through protection and enhancement of the water environment. They offer services at the state level as well as locally, through the 17 geographical Local Sections. Sinónimos: CWEA
Abbreviation: CWEA
Calorific Value
Calorific Value Sinónimos: Thermal Energy

Capacity-Linked water and sanitation for Africa's peri-urban and Rural Areas
A Collaborative Project (Contract # 265676; duration: 1.3.2011 – 28.2.2014) within the EU 7th Framework Programme Theme 6 – 'Environment (including climate change)' Sinónimos: CLARA
Abbreviation: CLARA
Capillary water
Capillary water is held in pores that are small enough to hold water against gravity, but not so tightly that roots cannot absorb it. This water occurs as a film around soil particles and in the pores between them and is the main source of plant moisture. As this water is withdrawn, the larger pores drain first. The finer the pores, the more resistant they are to removal of water. As water is withdrawn, the film becomes thinner and harder to detach from the soil particles. This capillary water can move in all directions in response to suction and can move upwards through soil for up to two meters, the particles and pores of the soil acting like a wick.
Capillary Zone
The capillary zone is the area in the soil where water can rise up slightly through the cohesive force of capillary action. It is generally an intermediate zone in the vadose zone between the dry zone, above the groundwater table.

Capital Cost
Funds spent for the acquisition of a fixed asset, such as sanitation infrastructure.
Carbon to Nitrogen Ratio
The ratio of the mass of carbon to the mass of nitrogen in a substrate. It is often expressed as a single number representing the carbon content. A balanced carbon – nitrogen ratio is relevant for composting and anaerobic digestion. If the digestion process is hampered by a lack of carbon (low C/N ration) organic material (e.g. household waste) can be added. To prevent a lack of nitrogen urine can be added. Sinónimos: C/N, C/N ratio, C:N Ratio, X:N
In the absence of sewers and if wastes and wastewater cannot be reused on-site, these products need to be collected and transported in a human-powered or motorised vehicle.

Catchment Area
Central American Industrial Research Institute
Central American Industrial Research Institute Sinónimos: ICAITI
Abbreviation: ICAITI

Central Public Health and Environmental Engineering Organisation
The Central Public Health and Environmental Engineering Organisation (CPHEEO) is Technical Wing of the Ministry of Urban Development, Government of India Sinónimos: CPHEEO
Abbreviation: CPHEEO
Centralised System
Centralised systems are infrastructures such as drinking water or wastewater treatment plants, which treat large amounts of water from many households in one single spot. Centralised systems thus require either the collection of waste and wastewater from individual houses or the redistribution to the households (i.e. drinking water). Centralised systems thus imply the construction of a piping system (water distribution system or sewers) and / or other means of collection and distribution (e.g. cartage). Sinónimos: Central System

Centralised Water Supply
Centralised (drinking) water supply refers to the centralised treatment and purification of water sources and subsequent distribution to different water users (households, industry, agriculture) through a large water distribution network. Sinónimos: Centralised Water Supply

A cesspit is an ambiguous term either used to describe an underground holding tank or a soak pit. An underground pool (also called cesspool) is a tank pit used for the temporary collection and storage of faeces, excreta or faecal sludge. The pit is lined with bricks or concrete, covered with a slab and needs to be emptied frequently. When soil conditions allow, the pit is not constructed watertight (similar to a soak pit) allowing liquid to leach out, while solids decay and collect in the base. A soak pit requires less frequent emptying but leachate infiltration may cause groundwater pollution. Sinónimos: Cess Pit, Cesspool, Underground Holding Tank
Colony forming units (CFU) is a measure indicating the number of microorganisms in a sample capable of multiplying and forming a colony on cultivation plates. CFU are often used to control or monitor the removal of pathogens in water and wastewater treatments. Sinónimos: Colony Forming Units

Channelling occurs, when a flow in a reactor does not follow the prospected flow schema, but directly flows from the inlet to the outlet without mixing with the rest of the reactor content. In water purification and treatment units, this results in a non-respect of the hydraulic retention time and in consequence insufficient treatment. Sinónimos: Short-circuiting

A system with open ditches for the discharge of rainwater exist in most urbanised areas. The ditches usually drain-off rainwater into rivers or sometimes into agricultural irrigation canals. Unauthorised discharge of domestic waste into the system is quite common leading to surface water pollution and spreading of pathogens. However, where no wastewater infrastructure exists, drainage of wastewater through the system could be a possible temporary solution considering an appropriate treatment (e.g. waste stabilisation ponds, constructed wetlands) before reuse or discharge. In this case drains should be covered by concrete slabs to prevent blockages by litter and humans from getting in contact with their contents and rainwater should be allowed to enter the systems in periodic inlets.
Charcoal is a lightweight, black, porous material similar to coal. It consists of carbon (about 50 to 95 %) and volatile chemicals and ash. Charcoal is usually produced by slow pyrolysis, the heating of wood, sugar, bone char, or other substances in the absence of oxygen. It can also be produced by some enzymatic conversion of organic mater. The backbones of charcoal are polycondensed aromatic moieties which are chemically and biologically persistent. Charcoal is a valuable soil amendment (see also terra preta), retaining nutrients at their surface and improving the soil structure leading to enhanced water and air retention.
Chemical Oxygen Demand
A measure of the amount of oxygen required for chemical oxidation of organic material in water by a strong chemical oxidant (expressed in mg/L). COD is always equal to or higher than BOD since it is the total oxygen required for complete oxidation. It is an indirect measure of the amount of organic material present in water or wastewater: the more the organic content, the more oxygen is required to chemically oxidise it (high COD). A high organic content is generally an indictor for water pollution. The COD subtracted by the BOD gives an indication of the non-biodegradable chemicals and thus the toxicity of the water. See also: COD/BOD5 Ratio Sinónimos: COD
Chemical Sedimentation
Chemical sedimentation is like normal sedimentation but coagulants are used in order to neutralise repelling surface charge of particles. Once these repelling surface charges are neutralised, the particles attach to each other forming clusters and flocs, which become heavier and therefore settle more easily to the bottom.

Chemical Treatment
Chemical treatment of wastewaters uses chemicals to degrade and remove pollutant or pathogens form wastewaters. In regard to wastewater, a typical chemical treatment is the co-precipitation of iron and phosphorus (e.g. in activated sludge systems). Other common chemical treatments are advanced oxidation processes (e.g. ozonation) used, where pollutants are toxic to bacteria and a biological treatment is not possible. A typical drinking water chemical treatment is chlorination

Chlorination generally refers to the addition of chlorine to water or sewage in order to kill pathogen and achieve disinfection.

Chlorination (centralised)
Chlorination is one of many methods that can be used to disinfect water. It is a chemical disinfection method that uses various types of chlorine or chlorine-containing substances for the oxidation and disinfection of what will be the potable water source.Centralised chlorination refers to the use of chlorine to disinfect water in a centralised drinking water treatment plant as a primary or secondary disinfection. Primary disinfection is when water is disinfected within the treatment plant, while secondary disinfection is when water is disinfected throughout the distribution system. Sinónimos: Centralised chlorination
What is Chlorination?
Cholera is an acute infection of the intestine, which begins suddenly with painless watery diarrhoea, nausea and vomiting. Most people who become infected have very mild diarrhoea or symptom-free infection. Malnourished people in particular experience more severe symptoms. Severe cholera cases present with profuse diarrhoea and vomiting. Severe, untreated cholera can lead to rapid dehydration and death. If untreated, 50% of people with severe cholera will die, but prompt and adequate treatment reduces this to less than 1% of cases. Cholera outbreaks can occur sporadically in any part of the world where water supplies, sanitation, food safety and hygiene practices are inadequate. Overcrowded communities with poor sanitation and unsafe drinking-water supplies are most frequently affected.
Cistern Flush Toilet
The cistern flush toilet is usually made of porcelain and is a mass-produced, factory-made user interface. The flush toilet consists of a water tank that supplies the water for flushing the excreta and a bowl into which the excreta are deposited. Excreta are flushed away with water stored in the cistern (depending on the type between 6 to 20 litres per flush). Cistern-flush toilets provide a high level of convenience for the user but their installation can result in a significantly increase of the fresh water consumption and increase of wastewater to be collected and treated. Dual flush toilets (with a smaller flush-volume for urine), low-flush toilet and urine diverting toilets are available in order to reduce the amount of generated blackwater. Sinónimos: Flush Toilet
City Sanitation Plan
City Sanitation Plans are strategic planning processes for citywide sanitation sector development. Addressing technical and non-technical aspects of sanitation services, City Sanitation Plans include the vision, missions, and goals of sanitation development as well as strategies to meet these goals. Sinónimos: City Sanitation Master Plan, CSP, CSPs
Abbreviation: CSP

City Sanitation Task Force
City Sanitation Task Force Sinónimos: CSTF
Abbreviation: CSTF

Clay Pot and Porous Capsule Irrigation Network
This is an old irrigation system that has been modernised and reapplied in water scarce areas. It consists of using clay pots and porous capsules (see also pitcher irrigation) to improve irrigation practices by increasing storage and improving the distribution of water in the soil. Sinónimos: Clay Pot Irrigation Network, Porous Capsule Irrigation Network
Clean Development Mechanism
The Clean Development Mechanism allows a country with an emission-reduction or emission-limitation commitment under the Kyoto Protocol (often, industrialised countries) to implement an emission-reduction project in developing countries. The former are hence able to buy emission reductions by achieving them in countries where it is cheaper to reduce greenhouse gas emissions – at the same times, they fund investments into clean technologies in developing countries.
Abbreviation: CDM

Co-composting is the controlled aerobic degradation of organics, using more than one feedstock (faecal sludge, excreta, organic solid waste, etc.). Faecal sludge has a high moisture and nitrogen content, while biodegradable solid waste is high in organic carbon and has good bulking properties (i.e., it allows air to flow and circulate). By combining the two, the benefits of each can be used to optimize the process and the product. Other organic materials, which can be used or subjected to co-composting, comprise animal manure, sawdust, wood chips, bark, and slaughterhouse waste, sludge or solid residues from food and beverage industry. See also compost or composting.
Coagulants are chemicals used to enhance sedimentation. Coagulants neutralise surface charges of repelling particules, allowing them to approach, attach and form clusters. The clusters are larger in size and heavier and thus more easy to settle and remove from the water. See also coagulation or chemical sedimentation. Sinónimos: Flocculant

The destabilization of particles in water by adding chemicals (e.g., aluminium sulphate or ferric chloride) so that they can aggregate and form larger flocs. Coagulation is often used in combination with flocculation.
Coagulation and floculation describe the chemical process of contact and adhesion whereby the particles of a dispersion (colloids) form larger-size cluster (flocs or flakes) allowing them to be more easely removed from water (e.g. by settling). The coagulation-flocculation processes facilitate the removal of suspended and colloidal particles. It’s used in the first stage of solids-liquids separation: settling, flotation or filtration.

COD/BOD5 Ratio
The ratio within the chemical oxygen demand (COD) and the biological oxygen demand over 5 days (BOD5) indicates the level of biodegradability of a sample. A low ratio COD/BOD5 (less than 2.0 or 2.5) indicates a high biodegradability, what means that it can be treated easily by a biological treatment. See also: Biological Oxygen Demand 5 Sinónimos: COD/BOD5, COD:BOD5, COD:BOD5 ratio
Coliform Bacteria
Coliform bacteria are defined as rod-shaped, Gram-negative organisms, which ferment lactose and produce acids and aldehydes. The coliforms include Escherichia, Klebsiella, Enterobacter, Citrobacter and may include Serratia and Edwardsiella. Coliforms are normally found in the aquatic environment and on vegetation but also in bodies and excreta. Therefore, they are also used as an indicator of faecal contamination of water. Sinónimos: Coliforms
Collection and Storage/Treatment
Collection and storage/treatment describes the ways of collecting, storing, and sometimes treating the products that are generated at the User Interface. Treatment that is provided by these technologies is often a function of storage and usually passive (e.g. no energy inputs). Thus, products that are ‘treated’ by these technologies often require subsequent treatment before Use and/or Disposal.
Colloidal Silver
Colloidal silver are tiny silver particles suspended in liquids. They are used as disinfectant in ceramic filters, preventing bacterial growth and assisting inactivation of bacteria.

Combined Cycle Power Plant
A combined cycle is characteristic of a power producing engine or plant that employs more than one thermodynamic cycle. Heat engines are only able to use a portion of the energy their fuel generated (usually less than 50%). The remaining heat (e.g., hot exhaust fumes) from combustion is generally wasted. Combining two or more thermodynamic cycles, such as the Brayton cycle and Rankine cycle, results in improved overall efficiency. Sinónimos: CCPP
Abbreviation: CCPP
Combined Heat and Power
Cogeneration or combined heat and power (CHP) describe the simultaneously generation of both electricity and useful heat. By-product heat at moderate temperatures (100-180°C) can also be used in absorption chillers for cooling. A plant producing electricity, heat and cold is sometimes called trigeneration or more generally: polygeneration plant. Sinónimos: CHP, Cogeneration
Combined Sewer
Combined sewers collect blackwater, greywater and stormwater runoff in one ant the same single pipe system. Combined sewers provoke the pollution of little polluted water by mixing it with heavily polluted water. This particularly results in pollution when sewers overflow during heavy rain periods. As combined sewers need to be large, they can also be more expensive to install. Today, combined sewers are perceived as obsolete and in newer construction separated sewer systems are installed instead, although many systems remain combined as the replacement of an existing systems would be too expensive.

Combined Sewer Overflow
A combined sewer overflow, or CSO, is the discharge of wastewater and stormwater from a combined sewer system directly into a river, stream, lake or ocean. Sinónimos: CSO
Abbreviation: CSO

Command and Control Tools
Command and Control Tools are direct regulations of requirements, bans and rules. With command and control tools, you only change the behaviour of people because they want to avoid penalties for non-compliance. People don't necessarily also change their values; that is also the reason why command and control tools only work when they can really be enforced, and when those who do not comply are actually charged.

Command Area
The area of the spate irrigation scheme that can be irrigated (provided that water is available) and is fit for cultivation.
Commercial Utility
Commercial Utility Sinónimos: CU
Abbreviation: CU

Community Action Planning
Community Action Planning Sinónimos: CAP
Abbreviation: CAP

Community Aided Total Sanitation
Community Aided Total Sanitation Sinónimos: CATS
Abbreviation: CATS

Community Based Organisation
A community based organisation is a small organization that does not have the registered status of an NGO but is a structured group of volunteers who work together to achieve a common goal of the community. Anyone can start their own CBO. Sinónimos: CBO, CBOs, Community Based Organization
Community Health Clubs
Community Health Clubs Sinónimos: CHC
Abbreviation: CHC

Community-led Total Sanitation
The CLTS is a methodology for mobilising communities to completely eliminate open defecation by taking their own action. Sinónimos: community led total sanitation
Abbreviation: CLTS
Community-Led Total Sanitation
Community-Led Urban Environmental Sanitation
Community-Led Urban Environmental Sanitation (CLUES) presents comprehensive guidelines for the planning and implementation of environmental sanitation infrastructure and services in disenfranchised urban and peri-urban communities, emphasising stakeholder participation. Sinónimos: CLUES
Abbreviation: CLUES

Compact Constructed Wetland
A CCW is a small-scale constructed wetland, built individually for one household. It works in connection to a three chambered septic tank, from where blackwater flows from the last chamber, passing through the constructed wetland into an impounding basin. The basin accumulates the treated blackwater as well as grey water from the sink, laundry and bathroom plus storm water. Sinónimos: CCW, CCW constructed wetland
Abbreviation: CCW

Completely Autotrophic Nitrogen Removal Over Nitrite
Aerobic ammonium oxidising bacteria (nitrifiers) with Anammox bacteria perform simultaneously a two step reaction under oxygen-limited conditions in one reactor. Sinónimos: CANON
Compost is decomposed organic matter that results from a controlled aerobic degradation process. In this biological process, microorganisms (mainly bacteria and fungi) decompose the biodegradable waste components and produce an earth-like, odourless, brown/black material. Compost has excellent soil-conditioning properties and a variable nutrient content. Because of leaching and volatilization, some of the nutrients maybe lost, but the material is still rich in nutrients and organic matter. Generally, Excreta or Sludge should be composted long enough (2 to 4 months) under thermophilic conditions (55 to 60 °C) in order to be sanitized sufficiently for safe agricultural use. This temperature is not guaranteed in most Composting Chambers, but considerable pathogen reduction can normally be achieved. Sinónimos: Biosolids
Compost Filter
A compost filter is a novel alternative pre-treatment method. Wastewaterflows through an aerobic filter. Solids (toilet paper, faeces) are held back in the filter, liquids are pumped to a secondary treatment facility (e.g. constructed wetland or waste stabilisation pond). There are two types of compost filters: chamber filter or hanging bags. Sinónimos: Pre-composting Tank, Rottebehaelter, Rottebehälter

Compost Pile
In this composting method, the waste is put in piles on the ground and regularly turned to allow aeration. The size of the pile may vary depending on the amount of waste and available space, but generally, it should be 1 to 2 m on each side and not more than 1.5 m in height. Chicken wire or wooden planks can be used to keep the pile together.

Composting is the process of controlled decomposition of organic solid matter (e.g. organic wastes such as plant residues, kitchen wastes, excreta, etc.) into CO2 and heat in the presence moisture. Composting is carried out by aerobic (requiring free or molecular oxygen found in air) microorganisms, mainly bacteria and funghi. Composting is simple and practiced by individuals in their homes, farmers on their land, and industrially by industries and cities. The desired end-product is an inoffensive and safe-to-handle (free of pathogens and weed seeds) material, that can be used as soil amendment to enhance organic matter and nutrient content

Composting Chamber
A composting chamber is designed to convert excreta and organics into compost. In composting toilets, faeces or excreta fall into a composting chamber together with cleansing material. Dry organic material such as sawdust is added to adjust moisture content and C/N ratio in order to obtain optimum conditions for thermophilic composting. Organic household waste can also be added for co-composting. Depending on the process, shorter or longer maturation periods and maybe also secondary treatment are required. Urine might be diverted to decrease humidity of the compost and to be reused separately.
Composting Pit
One simple method for composting organic waste is to put it in pits and let it turn into compost over a period of six months or more. This process requires some space and time but the main benefit is that the waste is not visible as it is buried in the pit. Sinónimos: Pit Composting

Composting Toilet
Composting toilets are toilet systems comprised of a superstructure, a pan or slab, and a vault or pit in which faeces or excreta fall together with cleansing material (the composting chamber). Dry organic material such as sawdust is added to adjust moisture content and C/N ratio in order to obtain optimum conditions for thermophilic composting. Composting toilets allow to treat bothexcreta and faeces as well as organic household or garden waste and to transform it into a valuable soil amendment. Sinónimos: Composting Latrine

Compressors are similar to pumps: both increase the pressure on a fluid and both can transport the fluid through a pipe. The increased pressure can directly be transformed into mechanical energy.
Condominial Sewer
Condominial sewerage is the application of simplified sewerage coupled with consultations and on-going interactions between users and agencies during planning and implementation. The term is used primarily in Latin America and is derived from the term condominio/condominium (housing block). Sinónimos: Condominial Sewer System, Condominial Sewerage
Condominial Sewerage
Condominial sewerage is the application of simplified sewerage coupled with consultations and ongoing interactions between users and agencies during planning and implementation. The term is used primarily in Latin America and is derived from the term condominio/condominium (housing block). Sinónimos: Condominial Sewer System, Condominial Sewerage
Confined Aquifers
Saturated permeable soil (sand or gravel) capped by an impermeable layer.
Conjunctive use describes the combined use of groundwater and surface water. In order to achieve higher water reliability, the natural hydrologic connection between ground and surface water is used as efficiently as possible. The idea of this management approach is to use surface water when the water table is high and change to groundwater when the water table is low. Sinónimos: Conjunctive water management
Conservation Agriculture
Conservation agriculture aims to achieve sustainable and profitable agriculture and subsequently aims at improved livelihoods of farmers through the application of the three conservation agriculture principles: minimal soil disturbance, permanent soil cover and crop rotations. Conservation agriculture holds tremendous potential for all sizes of farms and agro-ecological systems, but its adoption is perhaps most urgently required by smallholder farmers, especially those facing acute labour shortages. It is a way to combine profitable agricultural production with environmental concerns and sustainability and it has been proven to work in a variety of agro-ecological zones and farming systems. It has been perceived by practitioners as a valid tool for Sustainable Land Management (SLM).
Conservation Tillage
Conservation tillage embraces one principle of conservation agriculture "minimum soil disturbance" and includes practices that keep the disturbance of the soil and loss of organic matter to a minimum, reducing soil and water losses. Mostly, the soil is not turned using ploughs.
Consortium for Dissemination of DEWATS
Consortium for Dissemination of DEWATS Sinónimos: CDD
Abbreviation: CDD

Constant Vacuum System
A vacuum system where vacuum is maintained in the piping at all times. Used in large systems with more than 4 to 10 toilets and/or long pipes. Sinónimos: CVS
Constructed Wetland
A treatment technology for wastewater that aims to replicate the naturally occurring processes in wetlands. Constructed shallow ponds are lined and filled with some sort of filter material (substrate), usually sand, gravel, rock or soil, and planted with vegetation tolerant of saturated conditions (e.g. reeds). As wastewater flows through the ponds, the filter material filters out particles and microorganisms degrade the organics. See also free-water surface constructed wetland, horizontal subsurface flow constructed wetland, Vertical flow constructed wetland. Sinónimos: Constructed Treatment Wetland, CW, Planted Filter, Reed Bed, Wetpark
Contact time
Contact time is the product of the residual concentration of disinfectant (C), measured in mg/L at the outlet of the contact chamber, and the disinfectant contact time (T), measured in minutes. Contact time is increased when either the disinfectant concentration or the disinfectant contact time are increased, indicating a higher level of disinfection. The CT values required to achieve the necessary inactivation will depend on the microorganism targeted, pH, and temperature. Sinónimos: CT
Abbreviation: CT
What is Chlorination?
Contingency Planning
A process, in anticipation of potential crises, of developing strategies, arrangements and procedures to address the humanitarian needs of those adversely affected by crises. Sinónimos: CP
Continuous Stirred-tank Reactor
Continuous stirred tank reactors are reactors, in which there is a constant in- and out-flow and the content is completely mixed. Complete mixing occurs when the particles entering the tank are dispersed immediately throughout the tank. The particles leave the tank in proportion of their statistical population. The reactors can be round or square as long as the contents of the tanks are uniformly and continuously distributed. Sinónimos: CSTR
Contour Bunds
Contour bunds are bunds constructed along the contour lines. They are usually made of stones or soil (sometimes in variation with crop remains). They are constructed along a contour in order to best slow the water flowing down the slope, which increases the green water pool of the soil and prevents erosion. Sinónimos: Bunds
Conventional Biological Treatment
Conventional biological treatment means active sludge or enhanced active sludge systems and fixed film systems such as trickling filters or rotating biological contactors.
Conventional Gravity Sewer
Conventional gravity sewers are large networks of underground pipes that convey blackwater, greywater and, in many cases, stormwater from individual households to a (Semi-) Centralized Treatment facility, using gravity (and pumps when necessary). When blackwater and stormwater are collected in the same pipe, conventional sewers are also called combined sewers. Sinónimos: Combined Sewer, Combined Sewer System, Combined Sewerage, Conventional Sewer, Conventional Sewer System, Conventional Sewerage
Conveyance describes the transport of products from one functional group of a sanitation system to another. Although sanitation products may need to be transferred in various ways between functional groups, the longest, and most important gap is between User Interface or Collection and Storage/Treatment and (Semi-) Centralized Treatment. Therefore, for the sake of simplicity, Conveyance only describes the technologies used to transport products between these functional groups.
Cooling Tower
Cooling towers are one of the most common water recycling technologies in use by industry today. By taking advantage of water’s high heat of evaporation, cooling towers offer effective and relatively inexpensive cooling for a wide range of industrial uses. 2/3 industrial water is used for cooling water (removal of heat). In some industries such as electric power plants or oil refineries, even up to 90% of intake water is used for cooling. Cooling water is easy to treat and sometimes even of quite a good quality. It can therefore easily be reused for example for washing processes. However, once used for washing and eventually contaminated, an appropriate treatment system before reuse is required.

Cooling Water
Cooling water is the water used in industry to remove heat from processes. 2/3 industrial water is used as cooling water (removal of heat). In some industries such as electric power plants or oil refineries, even up to 90% of intake water is used as cooling. Cooling water is often not much polluted and can easily be reused for instance for cleaning processes. The heat, stored in the water after cooling can also be reused in other industrial or agricultural processes that require heating instead of cooling.

Core Humanitarian Standard
Core Humanitarian Standard Sinónimos: CHS
Abbreviation: CHS
Corporate Social Responsibility
Corporate Social Responsibility does not have one particular definition. Some define it as operating in a manner that meets or exceeds the ethical, legal, commercial and public expectations that society has of business; whereas other define it as doing business in an ethical way that respects people, society and the environment.
Corporation of Kochi
Corporation of Kochi Sinónimos: KOC
Abbreviation: KOC

Cost-Benefit Analysis
The objective of valuing costs and benefits is to understand their relation and compare them in monetary units, in order to utilise these operationalized benefits for better advocacy and decision-making.
Abbreviation: CBA
Creating an Enabling Environment
With Tools to Create an Enabling Environment you take care of a sound framework for sustainable sanitation and water management. A functioning enabling environment is the precondition for the implementation any other software or hardware tools. Certain basics such as a legal or institutional framework, sound enforcement bodies and human skills need to be developed before you can implement any other measures.

Crop Rotation
Crop rotation is a practice of growing different crops on the same land in a regular recurring sequence. It means the planned order of specific crops planted on the same field. It also means that the succeeding crop belongs to a different family than the previous one. The planned rotation may vary from 2 or 3 years to longer period. Rotation of crops is not only necessary to offer a diverse "diet" to the soil microorganisms, but as they are rooting at different soil depths hence are capable to explore the different soil layers for nutrients.
Crop Rotation
Cryptosporidium is a protozoan that can cause gastro-intestinal illness with diarrhoea in humans.
An environmentally resistant stage of a microorganism that helps it to survive periods of environmentally harsh conditions. Some protozoan parasites form infective, highly resistant cysts (e.g., Giardia) and oocysts (thick-walled spores, e.g., Cryptosporidium) during their life cycle. Sinónimos: Oocyst
Danish International Development Agency (DANIDA)
DANIDA is part of the Ministry of Foreign Affairs of Denmark Sinónimos: DANIDA
Abbreviation: DANIDA

Decentralisation describes the transfer of central government powers, competences and resources to the local government, closer to the people and/citizen. The concept can also be applied to infrastructures (e.g. decentralised wastewater treatments). Sinónimos: Decentralization

Decentralised Treatment System
Decentralised Treatment System Sinónimos: DTS
Abbreviation: DTS

Decentralised Wastewater Treatment System
A small-scale system used to collect, treat, discharge, and/or reclaim wastewater from a small community or service area. The treatment unit of DEWATS includes generally sedimentation and floatation (e.g. in septic tanks or biogas settlers); anaerobic treatment (e.g. in upflow baffled reactors or anaerobic filters); aerobic treatment (in sub-surface flow constructed wetlands or unplanted sand- or gravel filters); and a final aerobic treatment in maturation ponds. Sinónimos: DEWATS
Abbreviation: DEWATS
Decentralised Water Supply
Decentralised supply systems offer the possibility to provide safe drinking water where centralised supply systems are not feasible for economic or political reasons (e.g. in rural communities or informal settlements). Decentralised water supply refers to the small-scale purification and distribution o water. The decentralised treatment systems fall into three main categories: point-of-use systems (POU), point-of-entry systems (POE), and small-scale systems (SSS). POU and POE systems are designed for individual households while SSS can provide for community water supply, for emergency water supply in camps, or to purify water for sale in water kiosks. The choice of decentralised supply system depends on the local context and includes such factors as ease of use, maintenance needs, dependence on other utilities (e.g. electricity, fuel supply), and cost. Sinónimos: Decentralised Water Supply

Decentralized Treatment System
Decentralized Treatment System Sinónimos: DTS
Abbreviation: DTS

Deciding with the Community
Deciding with the community presents various approaches and tools that facilitate participatory decision making.

Decision Making Tools
Decision making tools are approaches to take mutually-accepted decisions that benefit as many stakeholders as possible.

Decomposition is the transformation of dead organic material (plants, animals, etc.) into more basic compounds and elements by biological and biochemical reactions. Sinónimos: Decay
Deep dug well
Deep dug wells are dug wells over 20 metres in depth, thus, unlikely to get contaminated but costly to construct.

Deep Shaft
Deep shafts are enhanced biological wastewater treatment systems. They are based on the process of activated sludge systems but particularly adapted where land is in short supply. Oxygen is injected into a return sewage stream, which is injected into the base of a deep columnar tank buried in the ground. As the sewage rises the oxygen forced into solution by the pressure at the base of the shaft breaks out as molecular oxygen providing a highly efficient source of oxygen for the microorganisms contained in the activated sludge. The rising oxygen and injected return sludge provide the physical mechanism for mixing. Mixed sludge and wastewater is decanted at the surface, the sludge is again enriched in oxygen while the supernatant continuously flows out of the system. The efficiency of deep shaft treatment can be high but they require high skilled labour for both, construction and operation and maintenance and large amount of energy.
Deep Well
A deep well is a hand-dug water well ranging more than 7m in depth and about 1.5m in diameter.

Definition of Boundaries
Setting clear boundaries is an important step in the development of any project. It makes it possible to stay focused on a specific area.

Dehydration of Faeces
When faeces are stored in the absence of moisture (i.e., urine), they dehydrate into a crumbly, white-beige coarse, flaky material or powder. The moisture naturally present in the faeces evaporates and/or is absorbed by the drying material (e.g., ash, sawdust, lime) that is added to them. Dehydration by adding dry organic material and long-term storage at high ambient temperature is the simplest treatment in order to transform faeces into a product that is safe for reuse as soil conditioner or disposal. Sinónimos: Application of Dehydrated Faeces
Dehydration Vaults
Dehydration vaults are used to collect, store and dry (dehydrate) faeces. Faeces will only dehydrate when the vaults are well ventilated, watertight to prevent external moisture from entering, and when urine and anal cleansing water are diverted away from the vaults. See also dehydration of faeces.
Demand Creation
Creating demand is essential to achieve that newly developed approaches and technologies actually come in to use.
Abbreviation: DC

Demand Creation Introduction
Creating demand is essential to achieve that newly developed approaches and technologies actually come in to use. Sinónimos: Demand Creation, Demand Creation Tools

Nitrification is an aerobic process carried out by a series of bacterial population that sequentially oxidize ammonium (NH4+) and organic nitrogen to nitrate (NO3-) with intermediate formation of nitrite (NO2-). The first step of nitrification is carried out by bacteria called nitrosomonas : 2NH4+ + 3O2 -> 2NO2- + 4H+ + 2H2O. The second step is carried out by nitrobacter bacteria: 2NO2-+O2 -> 2NO3-. The two steps can also be described in a single reaction: NH4+ + 2O2 -> NO3- + H2O + H+. Once nitrate has formed, the wastewater can undergo a denitrification process in order to reduce nitrate to nitrogen gas, that is released into the atmosphere. Since complete nitrification is a sequential reaction treatment process, systems must be designed to provide an environment suitable for the growth of both groups of nitrifying bacteria.
Denitrifying Ammonium Oxidation
This is the coupling of denitrification and Anammox processes in one single reactor. Sinónimos: DEAMOX
Deoxyribonucleic Acid
DNA is a nucleic acid present in nearly all living organisms as the main constituent of chromosomes. It is self-replicating and contains the genetic instructions used in the development and functioning of the cells. Sinónimos: DNA
Abbreviation: DNA
Department for Housing and Infrastructure Development
Department for Housing and Infrastructure Development Sinónimos: DHID
Abbreviation: DHID

Department for International Development
Department for International Development Sinónimos: DFID
Abbreviation: DFID

Department for Water Affairs
Department for Water Affairs Sinónimos: DWA
Abbreviation: DWA

Department of Infrastructure and Support Services
Department of Infrastructure and Support Services Sinónimos: DISS
Abbreviation: DISS

The process of removing the accumulated sludge from a sanitation storage or treatment facility (e.g. pit toilet, septic tank).
Detailed Project Report
Detailed Project Report Sinónimos: DPR, DPRs
Abbreviation: DPR

Deutsche Gesellschaft für Internationale Zusammenarbeit GmbH
Deutsche Gesellschaft für Technische Zusammenarbeit (GTZ) GmbH changed its name to The Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ) GmbH on 1 January 2011. Sinónimos: GIZ, GTZ
Abbreviation: GIZ

The process of reducing the water content of a sludge or slurry. Dewatered sludge may still have significant moisture content, but it typically is dry enough to be conveyed as a solid (e.g., shovelled).
Diammonium Phosphate
Diammonium Phosphate (DAP) is a common fertiliser with the chemical formula (NH4)2HPO4. Sinónimos: DAP
Abbreviation: DAP

Diarrhoea is the passage of loose or liquid stools more frequently than is normal for the individual. It is primarily a symptom of gastrointestinal infection. Depending on the type of infection, the diarrhoea may be watery (for example in cholera) or passed with blood (in dysentery, for example). Diarrhoea is caused by a variety of microorganisms including viruses, bacteria and protozoan.
Diesel Generator
Consists of both a diesel engine (converts chemical energy to mechanical energy) and a generator (converts mechanical energy to electrical energy).

The solid and/or liquid material remaining after undergoing anaerobic digestion.
Dioxins are a class of chemical contaminants that are formed during combustion processes such as waste incineration, forest fires, and backyard trash burning, as well as during some industrial processes such as paper pulp bleaching and herbicide manufacturing. The most toxic chemical in the class is 2,3,7,8-tetrachlorodibenzo-para-dioxin (TCDD). The highest environmental concentrations of dioxin are usually found in soil and sediment, with much lower levels found in air and water. Humans are primarily exposed to dioxins by eating food contaminated by these chemicals. Sinónimos: Dioxin, PCDD, PCDDs, PCDD’s
Abbreviation: PCDD, PCDDs, PCDD’s
Direct Surface Groundwater Recharge
In direct groundwater recharge water moves from storage above-ground (e.g. a spreading basin or ditch) to the aquifer via soil percolation. Most of the existing large-scale artificial recharge schemes in Western countries make use of this technique. In general direct surface recharge systems based on percolation have relatively low construction costs and are easy to operate and maintain.

The elimination of (pathogenic) microorganisms by inactivation (using chemical agents, radiation or heat) or by physical separation processes (e.g., membranes). The process is used for water purification or for advanced or tertiary wastewater treatment.
Disinfection By-product
The use of chemical disinfectants in water treatment usually results in the formation of chemical by-products, some of which are potentially hazardous. If chlorination is practised, the trihalomethanes, of which chloroform is the major component, are likely to be the main disinfection by-products, together with the chlorinated acetic acids in some instances. However, the risks to health from these by-products are extremely small in comparison with the risks associated with inadequate disinfection, and it is important that disinfection should not be compromised in attempting to control such by-products. Sinónimos: CDBP, CDBPs, DBP
Abbreviation: DBP
How to measure chlorine residual in water
Dissolved Oxygen
The concentration of oxygen dissolved in water, expressed in mg/l or as percent saturation, where saturation is the maximum amount of oxygen that can theoretically be dissolved in water at a given altitude and temperature.
Dissolved oxygen
Dissolved Oxygen
The dissolved oxygen (DO) is oxygen that is dissolved in water. The oxygen dissolves by diffusion from the surrounding air; aeration of water that has tumbled over falls and rapids. Sinónimos: Dissolved O2
Distributed Energy Resource
Distributed energy resource (DER) systems are small-scale power generation technologies (typically in the range of 3 kWe to 10000 kWe) used to provide an alternative to or an enhancement of the traditional electric power system. Sinónimos: DER
Abbreviation: DER
District Water, Sanitation and Health Education Committees
District Water, Sanitation and Health Education Committees Sinónimos: D-WASHE, D-WASHEC
Abbreviation: D-WASHEC

Double Entry Accrual Accounting System
Double Entry Accrual Accounting System Sinónimos: DEAAS
Abbreviation: DEAAS

Double Pit Latrine
Double pit latrines are latrines with several pits used in alternation. By constructing twin pits, it is possible to dig out a filled pit only after it has stood for a while (approximately one year) allowing the faecal matter to degrade while the other pit is put in use. Thus smell and the health risk during excavation will be reduced. Sinónimos: Twin-pit Latrine, Twin-pit Toilet

Double Ventilated Improved Pit
The double VIP has almost the same design as the single VIP with the added advantage of a second pit that allows it to be used continuously and permits safer and easier emptying. Sinónimos: Double VIP
Dried Faeces
Dried Faeces are Faeces that have been dehydrated until they become a dry, crumbly material. Dehydration takes place by storing Faeces in a dry environment with good ventilation, high temperatures and/or the presence of absorbent material. Very little degradation occurs during dehydration and this means that the Dried Faeces are still rich in organic matter. However, Faeces reduce by around 75% in volume during dehydration and most pathogens die off. There is a small risk that some pathogenic organisms can be reactivatedunder the right conditions, particularly, in humid environments. Sinónimos: Dehydrated Faeces
Drilled Well
Drilled Well Sinónimos: Borehole, Tubewell

Drilling Fluid
The addition of particular substances, e.g. natural clay, bentonite, organic polymers, air, foam, fibres, fresh cow-dung, to drilling water increases viscosity and hence improves removal of cuttings and stabilises the borehole.
Drinking Water
Freshwater that is chemically and biologically safe for human consumption, naturally or by purification. Sinónimos: Potable Water

Drip Irrigation
In drip irrigation, water flows through a filter into special drip pipes, with emitters located at different spacing. Water is discharged through the emitters directly into the soil near the plants through a special slow-release device. If properly designed, installed, and managed, drip irrigation may help achieve water conservation by reducing evaporation and deep drainage as compared to other types of irrigation such as flood or overhead sprinklers since water can be more precisely applied to the plant roots.
Dry Cleansing Material
Dry Cleansing Materials are solid materials used to cleanse one-self after defecating and/or urinating(e.g., paper, leaves, corncobs, rags or stones). Depending on the system, Dry Cleansing Materials may be collected and separately disposed of. Although extremely important, a separate menstrual hygiene products like sanitary napkins and tampons is often forgotten. In general (though not always), they should be treated along with the solid waste generated in the household.
Dry Digestion
Low-rate anaerobic digestion systems are classified according to the percentage of total solids (TS) in the waste stream. Dry digestion means that the TS content is higher than 20 %. Sinónimos: High-solids Digestion

Dry Toilet
A dry toilet is a toilet that operates without flushwater. The dry toilet may be a raised pedestal on which the user can sit, or a squat pan over which the user squats. In both cases, excreta (both urine and faeces) fall through a drop hole.
Drying Bed
Drying beds are either planted or unplanted sealed shallow ponds filled with several drainage layers and designed for the separation of the solid from the liquid fraction of (faecal) sludge from latrines, septic tanks, biogas reactors, trickling filters, etc. Sludge is dried naturally by a combination of percolation and evaporation and evapotranspiration. When drying beds are covered with plants, evaporation is enhanced by transpiration (evapotranspiration). See also planted drying beds and unplanted drying bed.

Dual Flush Toilet
A dual-flush toilet is a variation of the flush toilet designed to save water by using two buttons or handles to flush different levels of water.

Electronic waste may be defined as discarded computers, office electronic equipment, entertainment device electronics, mobile phones, television sets and refrigerators. This definition includes used electronics which are destined for reuse, resale, salvage, recycling, or disposal. Others define the re-usables (working and repairable electronics) and secondary scrap (copper, steel, plastic, etc.) to be "commodities", and reserve the term "waste" for residue or material which is dumped by the buyer rather than recycled, including residue from reuse and recycling operations. Sinónimos: E-Scrap, Electronic Equipment, Electronic Waste, Waste Electrical, WEEE
Abbreviation: WEEE
Electronic Waste
Ecological Sanitation
An approach that aims to safely recycle nutrients, water and/or energy contained in excreta and wastewater in such a way that the use of non-renewable resources is minimized. Sinónimos: Ecosan, Re-use Oriented Sanitation, Resources-Oriented Sanitation
Ecological Society of America
The Ecological Society of America (ESA) is a nonpartisan, nonprofit organization of scientists founded in 1915 to: promote ecological science by improving communication among ecologists; raise the public's level of awareness of the importance of ecological science; increase the resources available for the conduct of ecological science; and ensure the appropriate use of ecological science in environmental decision making by enhancing communication between the ecological community and policy-makers. Sinónimos: ESA
Abbreviation: ESA
The Compendium of Sanitation Systems and Technologies was first published in 2008 during the International Year of Sanitation, and the Second Edition will be published late 2013. The document's popularity is its brevity - ordering and structuring a huge range of information on tried and tested technologies in a single document. As in the first edition only proven technologies that are appropriate for low- and middle-income settings are presented. Also, only improved sanitation technologies are presented, featuring safe, hygienic, and accessible sanitation. In the eCompendium edition the whole range of urban, peri-urban and rural technologies (e.g. from simple pits to conventional sewers) are presented. Sinónimos: The eCompendium of Sanitation Systems and Technologies

Economic Issues
Economic issues provides readers with a short background on the economic importance of water and sanitation.

Economic Tools
With economic tools, people change their behaviour because the want to achieve maximal benefit at minimal cost. Economic tools involve the use of prices and other market-based instruments to provide monetary incentives to change behaviour.

Ecosan Project Steps
The guidelines and toolbox presented in the GTZ ecosan source book aim to address the needs and interests of initiators, planners, practitioners and other stakeholders in the preparation and implementation of ecological sanitation (ecosan) projects. This process should be participation oriented, including all stakeholders. The GTZ ecosan approach aims to supply these groups with methods, material, information and ideas as to how they structure the working steps of a particular project.
Ecosystem Services
The benefits derived from material and energy flows in an ecosystem.

The Ecoville is a permanent relocation site for victims of the Sendong typhoon, in Barangay Lumbia. The settlement is currently under construction and aims at becoming a sustainable and self-reliant community. Xavier University donated the land for this site and is organising its construction and development. Sinónimos: Xavier Ecoville, XE
Abbreviation: XE
Xavier Ecoville
Effective Microorganism
EM stands for Effective Microorganism referring to mixed culture microbial inoculants composed of several species of beneficial microorganism (lactic acid bacteria, photosynthetic bacteria, and yeast). The microorganism live together in symbiosis, each one produces something that is needed by the other one and it is pathogen free. EMs are mainly used as soil amendment or to control waste degradation. EM has been trademarked and is available commercially. But it is often expensive and spoils after some weeks as they are manipulated for commercialisation. Effective microorganisms, depending on the purpose, can also be obtained at home. For lacto-fermentation the easiest way to obtain an effective microbial mix is probably to take an inoculum from sauerkraut (pickled sour cabbage) liquid. Sinónimos: EM
Abbreviation: EM

Effluent is the general term for a liquid that leaves a technology, typically after blackwater or sludge has undergone solids separation or some other type of treatment. Effluent originates at either a collection and Storage or a (semi-) centralized treatment technology. Depending on the type of treatment, the effluent maybe completely sanitized or may require further treatment before it can be used or disposed of.
Electric Conductivity
The measured electric conductivity is used as a surrogate measure of total dissolved solids (TDS) concentration. By measuring the electrical conductivity of treated wastewater, its salinity can be assessed. Salt content is an important parameter for agricultural wastewater reuse. Sinónimos: EC
Abbreviation: EC
Wastewater Engineering, Treatment and Reuse
The term emergency is used to describe the crisis that arises when a community has great difficulty in coping with a disaster. Disasters can be either natural or induced by humans, can be slow or sudden onset and they result in a serious disruption of society, cause widespread human suffering and physical loss or damage, and stretch the community’s normal coping mechanisms to breaking point.
Emergency Phases
Emergency phases roughly describe the steps that affected people go through after an emergency. They typically include: immediate or acute emergency phase, about 1 week up to 3 months after the event; stabilisation phase, typically starting after 2-4 weeks and lasting until 2-6 months after the event; recovery phase with long-term action, taking several months and up to 1 or more years; settlement or long-term phase, lasting perhaps for years after the disaster. The exact duration depends on the event and the context of the emergency. Duration is not time-bound but rather depends on the achievement of set targets (indicators). Sinónimos: Emergency Response Phases
Emergency Response Unit
Im water-related emergencies, modular water treatment units of different sizes are applied to immediately provide safe drinking-water. They are called Emergency Response Units.
Emerging Technology
A technology that has moved beyond the laboratory and small-pilot phase and is being implemented at a scale that indicates that expansion is possible.
EMPOWERS is a regional programme mainly funded by the European Commission's MEDA (Mediterranean Regional Programme for Local Water Management) Water Programme, working in Egypt, Jordan, West Bank and Gaza. The EMPOWERS partnership aims at improving vulnerable populations’ long-term access and rights to water. For this, it follows a participatory water planning and management process with all stakeholders. The EMPOWERS approach seeks to improve water governance at the local level (water users; communities) and at the intermediate level (decentralised water managements and service providers in districts and states). The Guideline provided by EMPOWERS constitutes a practical and logical framework of activities based on the involvement of those who use and manage water, which leads towards improved local water governance and the development and implementation of integrated water development plans for towns, districts and villages. Furthermore, the guidelines advocate collaboration through dialogue to bring about a change in a way that water management professionals and water users work with each other. Sinónimos: EMPOWERS Approach
End-of-pipe techniques are methods used to remove already formed contaminants from a stream of air, water, waste, product or similar (instead of using cleaner production options). These techniques are called 'end-of-pipe' as they are normally implemented as a last stage of a process before the stream is disposed of or delivered. Sinónimos: end of pipe
The utilisation of products derived from a sanitation system.
Energisers are facilitation exercises. They raise the energy level of a training session by gaining back people’s attention and interest and therefore improving the training by itself. Enjoyable activities which refresh the group can be incorporated within a training course in order to stimulate the participants either physically, mentally or at best both together. It is very important to adjust the type of energisers as well as the required time frame and material to the specific context of the training.

Power derived from the utilisation of physical or chemical resources (e.g. the conversion of biogas to electricity), especially used to provide light and heat or to work machines.

Converts chemical energy (e.g. from diesel, petroleum) to mechanical energy.

Enhanced Biological Phosphorus Removal
Enhanced biological phosphorus removal (EBPR) is a wastewater treatment configuration applied to activated sludge systems for the removal of phosphate. It is based on the cultivation of special polyphosphate-accumulating organisms (PAO) in the anaerobic tank prior to the aeration tank. These bacteria accumulate large quantities of polyphosphate within their cells resulting in the accumulation of phosphorus in the biomass. The biomass is separated from the treated water at the end of the process and the phosphorus is thus removed. Generally speaking, all bacteria contain a fraction (1-2%) of phosphorus in their biomass due to its presence in cellular components, such as membrane phospholipids and DNA. Therefore as bacteria in a wastewater treatment plant consume nutrients in the wastewater, they grow and phosphorus is incorporated into the bacterial biomass. When PAOs grow they do not only consume phosphorus for cellar components but also accumulate large quantities of polyphosphate within their cells. Thus, the phosphorus fraction of phosphorus accumulating biomass is 5-7%. Sinónimos: EBPR
Abbreviation: EBPR
ENPHO is a service-oriented national Non Governmental Organization, established in 1990 that envisages contributing in sustainable community development by combining research and actions through the integrated programs in the environment and public health areas.
Ensuring Sustainability
Ensuring sustainability includes measures and actions to make a project sustainable, i.e. socially viable, economically feasible, and economically durable, and also lasting. Sinónimos: Ensure Sustainability

Enterohaemorrhagic Escherichia coli
Enterohaemorrhagic E. coli (EHEC), can cause severe foodborne disease. It is transmitted to humans primarily through consumption of contaminated foods, such as raw or undercooked ground meat products and raw milk.
Abbreviation: EHEC
Enteroinvasive Escherichia coli
Symptoms of the diseases caused by EHEC include abdominal cramps and diarrhoea that may in some cases progress to bloody diarrhoea (haemorrhagic colitis). Fever and vomiting may also occur.
Abbreviation: EEIC
Enteropathogenic Escherichia coli
EPEC are defined as E. coli belonging to serogroups epidemiologically implicated as pathogens but whose virulence mechanism is unrelated to the excretion of typical E. coli enterotoxins.
Abbreviation: EPEC
Enterotoxigenic Escherichia coli
Infection with ETEC is the leading cause of travellers' diarrhoea and a major cause of diarrheal disease in underdeveloped nations, especially among children. ETEC is transmitted by food or water contaminated with animal or human faeces. Although ETEC causes a significant amount of illness worldwide, the infection will end on its own and is rarely life-threatening.
Abbreviation: ETEC
Environmental Council of Zambia
Environmental Council of Zambia Sinónimos: ECZ
Abbreviation: ECZ

Environmental Flow
The minimum flow required keeping water related ecosystems alive.

Environmental Impact Assessment
An environmental impact assessment identifies and predicts the impact on of a measure or project on the environment and on man's health and well-being before the project is realised. Based on these potential consequences, alternative strategies may be sought or the project may be cancelled altogether if the impact is too negative. An EIA is completed with an auditing at project termination which compares actual outcomes with predicted outcomes. Sinónimos: Environmental-Impact-Assessment
Abbreviation: EIA
Environmental Issues
Making water management and sanitation more sustainable requires a certain degree of background knowledge on environmental issues such as the natural water and nutrient loops, the global extent of water pollution, plant requirements or land degradation.

Environmental Sanitation
Interventions that reduce peoples’ exposure to disease by providing a clean environment in which to live, with measures to break the cycle of disease. This usually includes hygienic management of human and animal excreta, solid waste, wastewater, and stormwater; the control of disease vectors; and the provision of washing facilities for personal and domestic hygiene. Environmental Sanitation involves both behaviours and facilities that work together to form a hygienic environment.
Escherichia Coli
Escherichia Coli is a type of bacteria that inhabits the intestinal tract of humans and other mammals. It is not necessarily harmful, but it is used as an indicator of faecal contamination of water. Sinónimos: E. Coli, E.Coli
European Community
European Community Sinónimos: EC
Abbreviation: EC

The enrichment of water, both fresh and saline, by nutrients (especially the compounds of nitrogen and phosphorus) that accelerate the growth of algae and higher forms of plant life and lead to the depletion of oxygen, blockage of sunlight and increasing temperatures. These changes may harm the original ecosystem. Eutrophication may occur naturally or as the result of anthropogenic influences (e.g. water pollution). Eutrophic comes from the Greek word eutrophos meaning well nourished. Eutrophic waters are distinguished from logographic waters, characterised by a nutrient deficiency, and mesotrophic waters with an intermediate level of productivity. Sinónimos: Hypertrophication
The phase change from liquid to gas that takes place below the boiling temperature and normally occurs on the surface of a liquid.
Evaporation Bed
Evapotranspiration beds are an alternative secondary treatment solution for greywater, pre-treated effluents from septic tanks, anal cleansing water or urine from urine diversion toilets in areas with high groundwater tables, or with soils that prevent wastewater percolation and where the productive reuse of these wastewater flowstreams is not a preferred option. The respective wastewater effluents are discharged into sealed up receptacles where the water evaporates from the soil or transpires from the plants growing there in a process called evapotranspiration. The dissolved organic matter is removed by bacteria and the remaining nutrients are taken up by plants.

The combined loss of water from a surface by evaporation and plant transpiration. It is the process by which water is transferred from vegetated soil to the atmosphere.
Ex-situ Target Population
Ex-situ emergency response is addressed to people that have (temporary) left their homes. The level and type of displacement vary. Settlements generally fall into one of the three categories: highly dispersed (dispersed settlement or host families); mass shelters (e.g. in schools, warehouses or mosques, mostly in urban areas) or in self-settlements (spontaneous camps) or previously planned camps (UNHCR 2007). People living ex-situ after an emergency event have the status of internally displaced persons, IDPs, or that of refugees if they cross international boundaries.
Excreta consists of urine and faeces that is not mixed with any flushwater. Excreta is small in volume, but concentrated in both nutrients and pathogens. Depending on the quality of the faeces, it has a soft or runny consistency.
Executing includes all the necessary activities to actually execute or implement a project (i.e., after the conceptualisation/planning phase).

Exploring Tools
These are tools to assess the current status and identify problems in a participatory manner, to define boundaries and to find out about who the important stakeholders are.

External Combustion Engine
An external combustion engine is a heat engine where an (internal) working fluid is heated by combustion of an external source, through the engine wall or a heat exchanger. The fluid then, by expanding and acting on the mechanism of the engine produces motion and usable work. The fluid is then cooled, compressed and reused in a closed cycle. Unlike the steam engine's use of water in both its liquid and gaseous phases as the working fluid, the Stirling engine encloses a fixed quantity of permanently gaseous fluid such as air or helium. As in all heat engines, the general cycle consists of compressing cool gas, heating the gas, expanding the hot gas, and finally cooling the gas before repeating the cycle. Sinónimos: EC Engine, Stirling Engine
Abbreviation: EC Engine
External Water
Water used for the production of an imported good.

The F-diagram shows faecal-oral disease transmission routes. Faeces which are not disposed or stored safely represent a health risk for humans, since pathogens in faeces can be transmitted through many different routes to humans – i.e. flies, contaminated foods, fingers (unwashed hands), through fields (crops) and fluids (water). The F-diagram depicts those relationships in a simple manner so that everyone can understand them.

Facultative Pond
A lagoon that forms the second treatment stage in waste stabilisation ponds (WSPs). It is a shallow pond (1 to 2m) consisting of an aerobic zone close to the surface and a deeper, anaerobic zone. AS algae grow on the surface they produce oxygen, which is consumed by aerobic bacteria in the middle of the pond degrading the BOD. In the lower zones of the pond, anaerobic digestion takes place. Sinónimos: FP
Faecal Coliform
Faecal coliforms are a group of bacteria (e.g. Escherichia coli) present in excreta. They are not necessarily harmful, but they are present in high numbers and relatively easy to detect. Therefore they are used to indicate the presence of other faecal bacteria, which may be present in small numbers only, but associated to a high health risk. Sinónimos: FC
Abbreviation: FC

Faecal Indicator Bacteria
Faecal indicator bacteria are bacteria used as indicator organism of faecal contamination. Typical faceal indicator bacteria are faecal coliforms or E. coli.

Faecal Sludge
Faecal sludge comes from onsite sanitation technologies, and has not been transported through a sewer. It is raw or partially digested, a slurry or semisolid, and results from the collection, storage or treatment of combinations of excreta and blackwater, with or without greywater. Examples of onsite technologies include pit latrines, unsewered public ablution blocks, septic tanks, aqua privies, and dry toilets. Faecal sludge management includes the storage, collection, transport, treatment and safe enduse or disposal of faecal sludge. Faecal sludge is highly variable in consistency, quantity, and concentration. Sinónimos: Fecal Sludge
Faecal Sludge Management
Faecal sludge management includes the storage, collection, transport, treatment and safe enduse or disposal of faecal sludge. Sinónimos: Fecal Sludge Management, FSM
Abbreviation: FSM
Faecal Sludge Management
Faeces refer to (semi-solid) excrement that is not mixed with urine or water. Depending on diet, each person produces approximately 50 L per year of faecal matter. Fresh faeces contain about 80% water. Of the total nutrients excreted, faeces contain about 12% N, 39% P, 26% K and have 107 to 109 faecal coliforms in100 mL. Sinónimos: Feces
Describes people or cultural groups who feel or express a relatively low inhibition when being exposed to or handling excreta

Describes people or cultural groups who react inhibited or dismissive in when being exposed to or handling excreta

Feedstock is the raw material entering anaerobic digesters and which is transformed for the production of biogas. Such feedstock can be agricultural wastes and manures, municipal or industrial wastewater, organic solid wastes or any other biodegradable vegetables (e.g. maïze, water hyacinths) or non-vegetal material.

Female Genital Mutilation
Female genital mutilation includes procedures that intentionally alter or cause injury to the female genital organs for non-medical reasons. It is highly not recommended by the World Health organisation and is regarded as a violation of human rights. Sinónimos: FGM
Abbreviation: FGM
This is the iron-salt-dependent decomposition of hydrogen peroxide, generating the highly reactive hydroxyl radical. This reaction is enhanced by solar irradiation (referred to as photo-Fenton).
Fermentation is the second step of anaerobic digestion. Fermentative bacteria transform sugars and other monomeric organic products from hydrolysis into organic acids, alcohols, carbon dioxide (CO2), hydrogen (H) and ammonia (NH3). Sinónimos: Acidogenesis

Ferric Chloride
Ferric Chloride Sinónimos: FeCl3
Abbreviation: FeCl3

Ferric Sulphate
Ferric Sulphate Sinónimos: FeSO4
Abbreviation: FeSO4

The combined irrigation and fertilisation is called fertigation. There are different way how fertigation can be done: mixing chemical fertiliser with irrigation water; using partly treated wastewater which contains still nutrients; mixing (separately collected) urine as a nutrient source and mixing it to the irrigation water. Fertigation helps saving freshwater resources and decreases the dependency on depleting mineral fertilisers. Generally, drip irrigation and subsurface drip irrigation are the most appropriate application method for fertigation.

Fertigation Water
Fertigation water is the water used for fertigation (the combined irrigation and fertilisation). In the SSWM toolbox, it refers to wastewater that has been partly treated but still contains sufficient nutrients to be used in fertigation. Fertigation water, depending on its initial composition, should have undergone both physical treatment, to prevent clogging of the irrigation system, and biological treatment to reduce pathogens and to limit the risk of crop contamination and the health risk to workers and end consumers.

Fertilisers are soil amendments applied to promote plant growth; the main nutrients present in fertiliser are nitrogen (N), phosphorus (P), and potassium (K) (the macronutrients). Other nutrients (micronutrient) are sometimes added in smaller amounts. There are inorganic fertilisers (mined or synthetically produced) or organic fertilisers. Due to a growing world population, today, the mineral resources of the main components of fertiliser (e.g. P) are depleting leading to exaggerate prices and the difficulty of small-farmer to provide them with sufficient fertiliser for food production. In sustainable sanitation systems, nutrients, initially contained in food, is recycled from wastewater products (e.g. urine, faeces etc.) providing an affordable and environmentally sound source of fertiliser at a local level. Sinónimos: Fertilizer
Field Capacity
Field capacity is the amount of soil moisture or water content held in soil after excess water has drained away and the rate of downward movement has materially decreased, which usually takes place within 2–3 days after a rain or irrigation in previous soils of uniform structure and texture.
Field Trenches
Field trenches increase precipitation harvesting by breaking the slope of the ground and therefore reducing the velocity of water runoff. By decreasing runoff, they enhance water infiltration and prevent soil erosion. Trenches can be seen as an extended practice of ploughing fields. They may be applied to all soil types and are not dependent on slope or rainfall conditions Sinónimos: Contour Furrows
The liquid that has passed through a filter.
A mechanical separation process using a porous medium (e.g., cloth, paper, sand bed, or mixed media bed) that captures particulate material and permits the liquid or gaseous fraction to pass through. The size of the pores of the medium determines what is captured and what passes through.
Financial Sustainability of WASH Services
Financing WASH Services sustainably – in the sense of securing service delivery after implementation – has proven to be a challenge. This is mainly due to a lack of planning and knowledge of post-installation costs and assigned responsibilities. Hence, a planning tool, such as an indicator framework for financial sustainability of WASH services is needed. Different organisations have recently produced such frameworks (e.g. the life-cycle cost approach from WASHCOST) that provide an overview of important aspects for reaching financial sustainability. Sinónimos: Financial Sustainability Framework

Financing means the organisation and acquisition of funds to pay for the full costs of a project (planning, building/ carrying out, operation & maintenance, monitoring & evaluation, etc.).

First Flush Device
First flush devices are used in rooftop rainwater harvesting (RTRWH) systems, in order to prevent debris, dirt, dust and droppings that collect on the catchment area from entering the collection and storage tank. Different types exist, such as float valve types, overflow flow types, flow rate types or electronic conductivity types. First flush diverter devices improve water quality, reduce tank maintenance and protect pumps. Sinónimos: First Flush Diverter, First Water Diverter
Rainwater Harvesting
Fish Pond
Fish can be grown in ponds that receive effluent or sludge where they can feed on algae and other organisms that grow in the nutrient-rich water. The fish, thereby, remove the nutrients from the wastewater and are eventually harvested for consumption. See also aquaculture.
Fixed Bed Reactor
Fixed bed, fixed film or attached growth reactors are biological wastewater treatment processes that employ an inert medium such as rock, plastic, wood, or other natural or synthetic solid material, that will support attached growth of active biomass responsible for degradation on its surface and within its porous structure reactors. Typical aerobic fixed bed reactors are trickling filters and biological disks or moving bed reactor (of type Kalness or Biostyr). Typical anaerobic fixed film reactors are anaerobic upflow filters. Sinónimos: Attached Growth Reactor, FBR, Fixed Film Reactor
Abbreviation: FBR

Fixed-film System
Fixed-film systems (also attached-growth systems) are biological wastewater treatment processes that employ a inert medium such as rock, plastic, wood, or other natural or synthetic solid material, that will support attached growth of biomass on its surface and within its porous structure. Wastewater comes into contact with the film contaiining the active fixed biomass either by pumping the water past the media in packed towers (i.e. trickling filter) or by moving the media past the wasewater to be treated (e.g. rotating biological contactor). Sinónimos: Attached-growth Systems, FFS
Floating Plant Ponds
A floating plant pond is a modified maturation pond with floating (macrophyte) plants. Plants such as water hyacinths or duckweed float on the surface while the roots hang down into the water to uptake nutrients and filter the water that flows by. Sinónimos: Macrophyte Pond
A very fine, fluffy mass formed by the aggregation of fine suspended particles, as in a precipitate. See also flocculation.
The process by which the size of particles increases as a result of particle collision. Particles form aggregates or flocs from finely divided particles and from chemically destabilized particles and can then be removed by settling or filtration. Flocculation is often used in combination with coagulation.
The process whereby lighter fractions of a wastewater, including oil, grease, soaps, etc., rise to the surface, and thereby can be separated. Sinónimos: Floatation
Flow Rate
The volumetric flow rate is the volume of fluid which passes through a given surface per unit time (e.g. m3/s, cubic meters or litres per second). Mass flow rate is the mass of substance which passes through a given surface per unit time. Sinónimos: Q
Abbreviation: Q

Fluidised-bed incinerator
A type of incinerator in which the stoker grate is replaced by a bed of limestone or sand that can withstand high temperatures. The heating of the bed and the high air velocities used cause the bed to bubble, which gives rise to the term “fluidised”
Flush Urinal
A flush urinal is a urinal used with water to flush away the urine. There are manual and automated flush techniques. Installing a flush urinal results in increased water consumption and the generation of the corresponding amount of wastewater. Waterless urinals, which work without water, have become increasingly popular. Sinónimos: flush urinals, waterborn urinals

Flushing Point
A flushing point is a capped pipe which is accessible on the surface for maintenance. Blockages can be cleaned or flushed out. They can be found at pipe junctions or where small-bore sewers are connected to a conventional sewerage. Sinónimos: Cleanout

Flushwater is the water discharged into the User Interface to transport the content and/or clean it. Freshwater, rainwater, recycled Greywater, or any combination of the three can be used as a flushwater source.
In the study of transport phenomena (heat transfer, mass transfer and fluid dynamics); flux is defined as flow per unit area, where flow is the movement of some quantity per unit time.
Fog is the same as clouds except that it touches the ground, whereas clouds have their base above the ground. When wind blows clouds over a mountain, fog is present wherever the clouds touch the ground. To a meteorologist, fog is present when visibility is less than 300 meters. Fog is composed of tiny liquid water droplets from less than a milimeter in diameter.
Fog Drip
Fog drip is a method to harvest the water contained in the fog. Fog harvesting provides a cheap complementary water source for arid and semiarid, rural regions. As the wind blows the fog through specially designed nets (fog collectors), tiny droplets of condensed water form on the mesh and are collected in a gutter and transported to a storage site. The collected water does meet the WHO standards and can be used as drinking water. One large fog collector, with a 40 m2 collecting surface, can produce up to an average of 200 litres per day throughout the year, costs around 1000 to 1500 USD each and can last 10 years.

Food Products
Any nutritious substance that people (or animals) eat or drink in order to maintain life and growth. Basic food products are produced in agriculture requiring soil, sun, water and nutrients.

Forage are plants grown to feed animals.

Fossa Alterna
The Fossa Alterna is a short cycle alternating, waterless (dry) double pit technology. Compared to the double VIP which is just designed to collect, store and partially treat excreta, the Fossa Alterna is designed to make an earth-like product that can be used as a nutrient-rich soil conditioner. The Fossa Alterna is dug to a maximum depth of 1.5 m and requires a constant input of cover material (soil, ash, and/or leaves).
Fouling refers to the accumulation of unwanted material on solid surfaces, most often in an aquatic environment. The fouling material can consist of either living organisms (biofouling) or a non-living substance (inorganic or organic). Fouling is usually distinguished from other surface-growth phenomena in that it occurs on a surface of a component, system or plant performing a defined and useful function, and that the fouling process impedes or interferes with this function. Sinónimos: Biofouling, Inorganic fouling, Organic Fouling
Framework Issues
Frameworks include institutional and legal frameworks, the former meaning the different institutions that are involved in planning and managing water and sanitation issues, and the latter meaning the laws that regulate the management of water and wastewater.

Free-Water Surface Constructed Wetland
A free-water surface constructed wetland aims to replicate the naturally occurring processes of a natural wetland, marsh or swamp. As water slowly flows through the wetland, particles settle, pathogens are destroyed, and organisms and plants utilize the nutrients. This type of constructed wetland is commonly used as an advanced treatment after secondary or tertiary treatment processes. Sinónimos: Free Water Constructed Wetland, Free Water Surface Flow Constructed Wetland, Free Water Surface Flow CW, Free-Surface Constructed Wetland, Free-Surface CW, FWS CW, Surface Flow Constructed Wetland
Water naturally occurring on the Earth's surface (lakes, rivers, etc) and underground (groundwater in aquifers and underground streams). Freshwater is characterized by having low concentrations of dissolved salts and other total dissolved solids. The term specifically excludes seawater and brackish water.

Fuel Cell
A fuel cell is an electrochemical cell that converts a source fuel into an electrical current. It generates electricity inside a cell through reactions between a fuel (often hydrogen) and an oxidant generating heat and water steam as by-products which then are transformed into mechanical energy and electricity. Natural gas is often used as a source of hydrogen and air as a source of oxygen.
Fulvic Acids
Fulvic acids are humic acids of lower molecular weight and higher oxygen content than other