Clarity of water expressed as nephelometric turbidity units (NTU) and measured with a calibrated turbidimeter.

The cloudy appearance of water caused by the presence of suspended and colloidal matter. In the waterworks field, a turbidity measurement is used to indicate the clarity of water. Technically, turbidity is an optical property of the water based on the amount of light reflected by suspended particles. Turbidity cannot be directly equated to suspended solids because white particles reflect more light than dark-colored particles and many small particles will reflect more light than an equivalent large particle.

Turdidity is a measure of the cloudiness or opaqueness of the water and is measured in nephelometric turbidity units (ntu). The turbidity is influenced by the amount and nature of suspended organic and inorganic material in water. Typically, the higher the concentration of the suspended material the greater the turbidity. The value of 1 ntu is recommend for drinking water, since higher turbidities could cause aesthetic problems or inhibit the ability of a system to disinfect the water. The source of turbidity could be fine sand, silt, and clay (i.e., soil separates); organic material, particles of iron and manganese or other metal oxides, rust from corroding piping, or carbonate precipitates. Turbidity measurements are typically not made on surfacewater sources - see Total suspended solids.

A measure of the extent to which light passing through water is reduced due to suspended materials. Excessive turbidity may interfere with light penetration and minimize photosynthesis, thereby causing a decrease in primary productivity. It may interfere directly with essential physiological function of fish and other aquatic organisms, making it difficult for fish to locate a good food source and altering water temperature.

The amount of solid particles suspended in water that cause light rays shining through the water to scatter. Turbidity is measured in nephelometric turbidity units (NTUs) or Jackson turbidity units (JTUs).

the measurement of water cloudiness; it may be affected by sediment and plankton concentrations

To water engineers, turbidity means cloudiness. Turbidity in water can be harmless, or it may indicate to water engineers that extra filtration, flocculation, and sedimentation is needed.

The degree of resistance to light in water caused by the presence of suspended solids which scatter or absorb the light, making the water look muddy or cloudy.

murkiness or cloudiness of water, indicating the presence of some suspended sediments, dissolved solids, natural or man-made chemicals, algae, etc.

a measure of the amount of suspended solids (particles) in water.

Is the measure of the relative clarity of the water. The greater the turbidity the murkier the water. Turbidity increases as a result of suspended solids in the water that reduce the transmission of light. The results of high turbidity is that the water raises in temperature as the suspended particles absorb heat from the sun.

The cloudy appearance of water caused by the presence of tiny particles. High levels of turbidity may interfere with proper water treatment and monitoring.

the cloudiness in a fluid caused by the presence of finely divided, suspended material

An optical property of water related to light attenuation. Turbidity increases as the amount of suspended sediments in the water column increase (IADC/CEDA, 1998).

thick or opaque with sediment Testing for Water Quality Return to the top of the page

(1) Condition of suspended matter in water. (2) A measurement of light passing through water. (3) Cloudy, muddy.

Turbidity is a measure of the murkiness of water, reflecting the amount of sediment in the water. High turbidity reduces the amount of light available to the plants and animals living in the water. It reduces the ability of plants to photosynthesise. It also makes it difficult for fish and other animals to see their prey. Turbidity should be less than 5 NTU (turbidity measurement scale) for water to support plant growth.

The cloudy water conditions caused by suspended solids.

This is a measure of suspended material in water that may cause it to look muddy or discoloured. It is measured in Nephelometric Turbidity Units (NTU)

Forestry Operations & Water Quality] The cloudy condition caused by suspended solids, dissolved solids, natural or human-developed chemicals, algae, etc., in a liquid.

An indicator of the amount of sediment suspended in water. It refers to the amount of light scattered or absorbed by a fluid. In streams or rivers, turbidity is affected by suspended particles of silts and clays, and also by organic compounds like plankton and microorganisms. Turbidity is measured in nephelometric turbidity units.

refers to the cloudy appearance of water contaminated with suspended solid particles.

The reduction of transparency of a liquid due to the scattering effect of light by suspended particles.

A measure of the light-transmitting properties of water used to indicate the quality of waters with respect to colloidal matter. Colloidal matter will scatter or absorb light and thus prevent its transmission.

A unit of measurement quantifying the degree to which light traveling through a water column is scattered by the suspended organic (including algae) and inorganic particles. The scattering of light increases with a greater suspended load. Turbidity is commonly measured in Nephelometric Turbidity Units (NTU), but may also be measured in Jackson Turbidity Units (JTU).

Measures the clarity of water. High turbidity results when there are a lot of particulates floating around and the water is cloudy. Low turbidity results when there are few floating particulates and the water is clear.

substances or particles that obscure light transmission

Muddiness, thickness, lack of clarity of a liquid or colour.

a technical term for describing the clarity of the water. Cloudy water is turbid water.

_ Suspended matter in water that causes scattering or absorption of light rays and a cloudy appearance.

The decreased clarity in a body of water due to the suspension of silt or sedimentary material.

the amount of particles contained within a water sample (visually measured: the more turbid the water, the more opaque it becomes).

the optical opacity of water containing suspended matter. Measured with a nephelometer

the level of suspended particulants in a waterway.

The pollution of water by suspended matter.

muddiness created by stirring up sediment or having foreign particles suspended

The degree to which a body of water is turbid.

The state, condition, or quality of opaqueness or reduced clarity of a fluid, due to the presence of suspended matter. ()

Turbidity means having sediment or foreign particles stirred up or suspended, usually within a liquid.

The muddiness or lack of clarity of a body of water or a stream

A general term describing the clarity of water; turbidity is caused by dissolved colored substances in water and by the suspended particles that absorb and reflect sunlight

is one of the most important parameters used to determine the quality of drinking water. The World Health Organization specifies 5 NTU (Nephelometric Turbidity Units) as the reference value of water for trade. The USEPA has recently adopted a final ruling that will implement new standards for turbidity in drinking water beginning in 1998— acceptable limits will drop from 5 NTU to 1 NTU for facilities serving more than 10,000 people. Turbidity measurement is also a requirement of wastewater treatment. ( http://www.chemetrics.com/)

A measure of non-transparency of water due to the presence of suspended matter.

an opaque or unclear appearance imparted to water by the presence of suspended foreign particles (soil, plankton, etc.)

particles, suspended in water or wastewater, that interfere with the passage of light; high turbidity makes water appear unclear or cloudy and is harmful to organisms such as fish

Having the sediment stirred up; murky, dense.

A condition in water or wastewater caused by the presence of suspended matter and resulting in the scattering and absorption of light. The analytical quantity is typically reported in turbidity units and determined by the measurement of light scattering using an instrument called a nephelometer.

Deficient in clarity or purity.

The degree of clearness of a liquid or the lack of visual clarity of a liquid. It is defined by the measure of light scattering due to the presence of particles suspended in the liquid. Turbidity is similar to opacity for particles suspended in the gas phase.

Presence of suspended and colloidal substances of various origins.

A state of reduced clarity in a fluid caused by the presence of suspended matter.

Thick or opaque with matter in suspension; muddy water.

the condition of a body of water that contains suspended materials such as clay or silt particles, dead organisms, or small living plants and animals.

A qualitative measurement of water clarity which results from suspended matter that scatters or otherwise interferes with the passage of light through the water.

The condition resulting from the presence of suspended particles in the water column which attenuate or reduce light penetration.

The measure of suspended material in a liquid.

Reduced water clarity resulting from the presence of suspended matter. (1)

A measure of the amount of light intercepted by a given volume of water due to the presence of suspended and dissolved matter and microscopic biota. Increasing the turbidity of the water decreases the amount of light that penetrates the water column. High levels of turbidity are harmful to aquatic life.

a measurement of the amount of suspended matter in an aquatic ecosystem

Opacity of water caused by suspended sediment or organic material.[ J K U V X Y Z

sediment or particles suspended in water, which reduce the clarity of the water

Particles in solution (e.g. soil or algae) which scatter light and reduce transparency.

A measure of the opaqueness of a liquid.

The relative clarity of water, which may be affected by material in suspension in the water.

Measure of the cloudiness of a waterbody due to suspended particles

Water cloudiness caused by suspended particles

The cloudy condition of the water due to the presence of extremely fine particles in suspension that cannot be trapped by the filter because they are too small. Adding a clarifier, such as an organic polymer or alum, will coagulate the particles and make the filter more efficient.

a measure of water cloudiness caused by suspended solids List of Glossary Terms

A river pollution measure; how much sediment is being carried in the water

A measure of the amount of suspended material (sediment) in water based on the relative ability of light to penetrate the water's surface. This cloudiness of water due to excess sediment, is an extremely important factor in maintaining aquatic diversity. Many sensitive organisms, especially fish, require relatively clear water conditions for reproducing and finding prey. Some organisms, like shell-fish are filter-feeders and continually filter the water in the environment. These organisms can become choked by sediment and eventually die in heavily turbid waters.

cloudiness or muddiness of water.

A cloudy condition in water due to suspended silt or organic matter.

A physical characteristic of water making the water appear cloudy.

thick or opaque with matter in suspension. Rivers and lakes may become turbid after a rainfall.

cloudiness caused by the presence of suspended solids in water; an indicator of water quality.

The cloudy or muddy appearance of a naturally clear liquid caused by the suspension of matter.

A measure of the amount of finely divided suspended mater in water, which causes the scattering and adsorption of light rays. Milky ice cubes and "floaties" in your water are caused by turbidity.

The cloudy or muddy appearance of water which is an indication of fine solids suspended in the water; this is usually measured by a light penetration test.

NTU 0.3(95% of Time) 0.03 0.02-0.05

"The term ""turbid"" is applied to waters containing suspended matter that interferes with the passage of light through the water or in which visual depth is restricted."

Cloudy water from fine particles suspended in the water that the filter can't trap. Clarifier or alum can help clump fine particles for filter to eliminate.

Any insoluble particle that imparts opacity to a liquid.

A measure of suspended matter or particles in water that block light penetration; cloudy or muddy in physical appearance. Turbidity reduces water clarity.

All source waters are naturally cloudy occasionally. Turbidity is a quantitative measure of cloudiness and levels are controlled by the treatment processes. 4 Formazin Turbidity Units

The weight of particulate matter per unit volume of sea water.

A reduction in water clarity or a cloudiness caused by soil particles or organic matter in the water. These particles may harm aquatic life by decreasing light availability for plant growth, increasing water temperature, clogging the gills of aquatic organisms, and covering habitat. Low turbidity values (at or below 25 nephelometric turbidity units (NTU)) generally indicate good water quality.

A measure of water cloudiness caused by the amount of suspended matter in the water

In waste water, that solid contaminating material which is more or less suspended in the water. Measured as resistance to light passing through a volume of water. Turbid water is "opaque"; pure water without TURBIDITY is transparent to light and is thus "clear".

The presence of fine suspended matter such as clay or silt in water causing the water to be cloudy or muddy in appearance.

the state of having sediment or foreign particles suspended or stirred up in water unconfined aquifer - an aquifer that discharges and recharges with an upper surface that is the water table

Having sediment or foreign particles stirred up or suspended in water.

the extent to which the passage of light through water is reduced by suspended matter

A suspension of fine inorganic or organic particles and other suspended impurities in water that cause cloudiness and will not readily settle due to small particle size. Generally to remove turbidity, the water is treated (by flocculation) and then filtered.

The quality (e.g., of water) of having suspended matter (e.g., clay, silt, or plankton), which results in loss of clarity or transparency.

Muddy or unclear water quality caused by suspended sediments.

Measurement of sediment and/or other particles stirred up or suspended in water.

A measure of the amount of material suspended in the water. Increasing the turbidity of the water decreases the amount of light that penetrates the water column. Sustained, high levels of turbidity are harmful to aquatic life.

The clouding of a naturally clear liquid due to suspension of fine solids. Because turbidity reduces the amount of light penetrating the water column, high turbidity levels are harmful to aquatic life.

A measure of the amount of suspended matter in water or aerosols in air; a-more precise term is attenuation which is the sum of scattering and absorption.

cloudiness in water derived from algae, suspended silt, or other impurities.

a measure of water cloudiness. Cloudiness is caused by suspended solids which scatter and absorb light rays.

Haziness or cloudiness in water because of suspended silt or organic matter.

Fine particles of suspended material that give water a muddy or milky appearance.

The cloudy appearance of water caused by the presence of suspended and colloidal matter. The water quality parameter indicating the clarity of water.Turbidity is measured by the amount of light that is reflected off particles in the water. It is measured by a nephelometer in nephelometric turbidity units (NTU).

a measure of the amount of light scattered and absorbed by water because of the suspended matter in the water.

The amount of particles in the water that allow for clarity. (How clear the water is).

Cloudy, dull, hazy water, due to microparticle suspension.

cloudy condition of the pool water

A measure of how particles suspended in water affect its clarity. Microorganisms, soil particles, plankton, or other organic/inorganic matter causes the cloudy or muddy appearance of water.

a measure of water clarity that expresses the degree to which light is scattered

The presence of suspended material such as clay, silt, finely divided organic material, plankton, and other inorganic material in the water.

A fisheries measurement of the total suspended solids in water expressed as nephelometric turbidity units (NTU).

current: sub-aquatic current induced by gravity flowage of water containing suspended sediments.

Cloudiness that results from suspended particles of dirt in the water. These particles usually are in two categories: larger, visible pieces that can easily be filtered out; and minute, invisible particles that can make water hazy. The more minute the particles, the finer the filter required.

A fine particulate matter that makes water appear cloudy. Increased turbidity decreases the effectiveness of chlorination or other types of disinfection.

Cloudiness of water caused by the suspension of minute particles, usually algae, silt, or clay.

amount of sediment or particles suspended in water. Upland: 1.) terrestrial ecosystems located away from riparian zones, wetlands, springs, seeps, and dry washes 2.) ecosystems made up of vegetation not in contact with groundwater or other permanent water sources (Mojave-Southern Standards & Guidelines, BLM). Value: degree of lightness in a color.

A qualitative term that refers to the concentration of suspended particles in the water.

the amount of solid particles that are suspended in water and that cause light rays shining through the water to scatter. Thus, turbidity makes the water cloudy or even opaque in extreme cases. Turbidity is measured in nephelometric turbidity units (NTU).

A cloudiness in transparent coating caused by finely suspended matter.

The degree of cloudiness of water caused by the presence of suspended particles or colloidal material. Turbidity reduces the transmission of light and is measured in Nephelometric Turbidity Units (NTU).

A measure of the amount of the light-scattering properties of water. It indicates how much silt, algae and other material is suspended in water. Highly turbid waters may look muddy, stain clothes, block irrigation sprays and pipes or harm aquatic organisms.

Cloudiness in water caused by the suspension of tiny particles (algae or detritus).

Relative opaqueness or cloudiness of water due to suspended or dissolved particles that block light penetration.

Suspended biological, inorganic and organic particles in water which may be in sufficient amount to make the water seem cloudy.

The degree of cloudiness of a water body caused by suspended solids. Jump to Top

Cloudiness of a liquid caused by suspended matter

The reduction in transparency of a continuous phase due to light scattering and absorption caused by a dispersed phase. Turbidity is thus a function of the size and concentration of the dispersed species.

The cloudy conditions caused by the suspended solids in liquid.

degree to which light is blocked because water is muddy or cloudy.

a measure of the degree of clarity of a solution. For cloudy water, turbidity would be high; for clear water, turbidity would be low.

Suspended matter in water or wastewater that scatters or otherwise interferes with the passage of light through the water.

The cloudy condition of the water due to the presence of extremely fine particles in suspension that are able to pass through the filter. Adding a flocculant or coagulant will clump the particles together so they can be trapped in the filter.

cloudiness; usually caused by fine sediments suspended in the water; it is measured by passing light through a sample of the water

Cloudy condition of water caused by finely divided microscopic material in suspension interfering with the passage of light.

Measures particles in the water, such as sediment and algae. Related to the depth sunlight can penetrate into the water. Higher turbidities reduce the penetration of sunlight in the water and can affect species of aquatic life that survive in the waterbody.

Cloudiness caused by fine visible and/or colloidal material in suspension that interferes with the normal passage of light through liquid.

a measure of the cloudiness of a liquid that is caused by the presence of fine suspended solids

Describes the opaque condition of a liquid containing suspended particles such as muddy water

The amount of small particles of solid matter suspended in water as measured by the amount of scattering and absorption of light rays caused by the particles.

Degree to which pool water is visually obscured by suspended particles.

The relative lack of clarity (cloudiness) of water, caused by suspended material (e.g. sediments), colored materials in solution, and plankton. Turbidity correlates (inversely) with available light for photosynthesis; can be measured with a transmissometer.

how cloudy the water is, influenced by plankton, sediment, water color, may limit plant growth if sunlight cannot penetrate.

Bold text Turbidity is a cloudiness or haziness of water (or other fluid) caused by individual particles (suspended solids) that are generally invisible to the naked eye, thus being much like smoke in air. Turbidity is generally caused by phytoplankton. Measurement of turbidity is a key test of water quality.