Water testing is a broad description for various procedures used to analyze water quality. Millions of water quality tests are carried out daily to fulfill regulatory requirements and to maintain safety
Testing may be performed to evaluate:
ambient or environmental water quality – the ability of a surface water body to support aquatic life as an ecosystem. See Environmental monitoring, Freshwater environmental quality parameters and Bioindicator.
wastewater – characteristics of polluted water (domestic sewage or industrial waste) before treatment or after treatment. See Environmental chemistry and Wastewater quality indicators.
“raw water” quality – characteristics of a water source prior to treatment for domestic consumption (drinking water). See Bacteriological water analysis and specific tests such as turbidity and hard water.
“finished” water quality – water treated at a municipal water purification plant. See Bacteriological water analysis and Category:Water quality indicators.
suitability of water for industrial uses such as laboratory, manufacturing or equipment cooling. See purified water.
Department of Homeland Security
The U.S. Department of Homeland Security is a cabinet department of the United States federal government, created in response to the September 11 attacks, and with the primary responsibilities of protecting the United States of America and U.S. territories (including protectorates) from and responding to terrorist attacks, man-made accidents, and natural disasters. See United States Department of Homeland Security.
The Homeland Security Presidential Directive 7 designates the Environmental Protection Agency as the sector-specific agency for the water sector’s critical infrastructure protection activities. All Environmental Protection Agency activities related to water security are carried out in consultation with the Department of Homeland Security. Possible threats to water quality include contamination with deadly agents, such as cyanide, and physical attacks like the release of toxic gaseous chemicals.
The principal U.S. federal laws governing water testing are the Safe Drinking Water Act and the Clean Water Act. The U.S. Environmental Protection Agency (EPA) issues regulations under each law specifying analytical test methods. EPA’ s annual Regulatory Agenda sets a schedule for specific objectives on improving its oversight of water testing
Water Quality Testing
In many parts of the world, water is not safe enough to drink. There are basic qualitative observations that quickly determine if water is not safe to consume. However, there are also many “invisible” substances that must be tested for professionally to identify the contaminants and to figure out how the specific polluted water can be purified. Testing can be done in the field with portable test kits or mobile laboratories. Water samples can also be collected and sent to a professional laboratory.
Provides clean water and protects human health
Many types of equipment are easy to handle and provide quick results
Equipment can be expensive
Some parts of the testing kits and laboratories are very sensitive and must be handled carefully
Needs trained labourers or even experts
Water is in continuous movement on, above, and below the surface of the earth. As water is recycled through the earth, it picks up many things along its path. Water quality will vary from place to place, with the seasons, and with the various kinds of rock and soil it moves through.
For the most part, it is largely natural processes that affect water quality. For instance, water moving through underground rocks and soils may pick up natural contaminants, even with no human activity or pollution in the area. In addition to nature’s influence, water is also polluted by human activities, such as open defecation, dumping garbage, poor agricultural practices, and chemical spills at industrial sites (see also water source protection).
Testing Your Drinking Water
Reasons to Test Your Drinking Water
Homeowners using this type of water supply should consider having it tested for the following reasons:
Unlike public water systems, private water supply testing is the voluntary responsibility of the homeowner. There are no government agencies or programs that routinely test private water systems for homeowners.
Surveys indicate that about half of the private water supplies have never been tested.
Additional studies have found that about 50 percent of private water systems fail at least one drinking water standard.
Many pollutants found in private water systems have no obvious symptoms and can only be detected through laboratory testing.
Water testing is generally economical and convenient with many testing laboratories located throughout the state.
Water testing provides vital information to document the quality of your drinking water. Data from previous tests may be necessary if you ever need to prove in court that a nearby land use has damaged your drinking water quality.
The only way homeowners can be certain that their water is safe to drink is to have the water tested periodically.
Tests to Have Done Routinely
While it is possible to have a water supply tested for many things, such a test is very expensive and unnecessary. Instead, homeowners should focus testing on a few standard parameters along with additional tests related to nearby land uses.
Private water supplies should be tested every year for total coliform bacteria and E. coli bacteria. Coliform bacteria includes a large group of many types of bacteria that occur throughout the environment. They are common in soil and surface water and may even occur on your skin. Large numbers of certain kinds of coliform bacteria can also be found in waste from humans and animals. Most types of coliform bacteria are harmless to humans, but some can cause mild illnesses and a few can lead to serious waterborne diseases.
If coliform bacteria are found in a water supply, a follow-up test can be done by the laboratory to look for E. coli–a type of coliform bacteria found only in human or animal wastes. A positive E. coli result is much more serious than coliform bacteria alone because it indicates that human or animal waste is entering the water supply.
Drinking water should be tested for pH and total dissolved solids (TDS) every three years. These tests are similar to a doctor taking your temperature–they are general tests that provide an index to the quality of your drinking water.
Water Quality Tests
Water Quality Tests:
This test is the most important of the nine water quality tests to measure water’s ability to support plants and animals. There are many different factors that affect the amount of dissolved oxygen in water, the main one being temperature. As temperature rises, less gas will dissolve.
Turbidity measures water clarity, which allows sunlight to penetrate to a greater depth. The main sources of turbidity are erosion, living organisms, and those from human endeavors
Total solids measures both dissolved and suspended solids. There are six major types of total solids; silt, clay, soil runoff, plankton, industrial waste, and sewage.
The PH of water is important to aquatic life. If the PH falls below 4 or above 9 everything is dead.
Temperature and Flow Rate
Temperature is a very important part of a river’s ecology. There are many natural and human factors that can affect a river’s temperature. Human factors include industry, development, and dams. To measure temperature and flow rate you must find two places along the river that are about 1.6 kilometers apart that have the same conditions, then two people measure the temperature at approximately the same time. If the difference is greater than 2 degrees Celsius, then there is thermal pollution. To find flow rate you use a buoyant object, we used an orange, and float it down the river.
Nitrogen is necessary for plant and animal life. Water is tested for nitrates to monitor and control eutrofication , which causes more plant growth and decay.
This nasty stuff is a certain bacteria that propagate in the digestive tracts of humans and animals. They coexist with other bacteria so they are often used as indicators of possible pathogenic contamination. There are many ways fecal coliform can enter a waterway such as animal waste, untreated sewage, combined sewage overflow, and septic tanks.
Biochemical Oxygen Demand
BOD is a measure of oxygen removed from an aquatic environment by aerobic microorganisms. It measures levels of organic pollution in lakes and streams.
Phosphates is a nutrient needed in growth. The phosphate ion is found in shells, bones, and in animal teeth. By removing phosphorous from sewage the amount of phosphate ions in the water will be lowered.
Good drinking water is very important to keep animals healthy. But what is good drinking water? Animal Health tests various aspects of water, such as the microbial count (colony forming units), content levels of various minerals and Chemical Oxygen Demand (COD). But the main test carried out by Animal Health is the one for suitability as livestock drinking water. Water testing at Animal Health is based upon on three pillars
water must be available at the location where the animals drink: the pipes cannot be clogged up, the flow of the water from the nipple must be good if the animal wants to drink;
water must not be harmful – this speaks for itself, as the production, growth and health of the animal must not endangered;
water must be tasty, i.e. the animals are willing to drink the water.
Nowadays the quality of products meant for human consumption (meat, eggs, milk) is being increasingly monitored. These products must be of a high and unsuspicious quality. The water the animals drink must not threaten the quality of the meat. Animal Health analyses water designated for livestock drinking water. The results show to what extent the above mentioned criteria are met.
Drinking water tests
The main thing a livestock farmer wants to know about the water at his farm, is its suitability as livestock drinking water. If the water is not suitable, Animal Health gives advice on options for improving the quality. For water testing, Animal Health has created what it refers to as drinking water packages. A water sample is subjected to many tests: e.g. chemical, bacteriological and organoleptical tests. Individual tests for water samples are possible as well, and individual packages can be created too. Water testing is a fine example of the versatility of Animal Health. The results of various laboratory departments that test the water are combined. That gives a complete picture of the suitability as drinking water. The advice that is linked to the results is specific for every submitted sample.
Techniques used for water testing include the following;
Ion chromatography: a chemical compound is used to separate ions such as nitrate, chlorine, and sulphate, and then they are measured using UV detection.
ICP: for metals and minerals (induced coupled plasma: the sample is dissolved in an acid environment and this acid is atomised in argon plasma of 10,000 °C; then metals and minerals emit specific light that is detected by a chip).
Automated colorimetric methods: some tests are carried out using a colorimetric method (ammonium, nitrite) in accordance with the Standardised NEN methods prescribed in the Netherlands.