Various types of water testing assist in determining whether specific chemicals or contaminants have affected a body of water to ensure water quality.

What is water analysis?

Water analysis is a method that is used to meet the regulatory requirements and the safety procedures that are needed for pollutant-free water.

There are many methods of water analysis such as physical, biological water analysis and chemical water analysis.

What are water analysis types?

To ensure the quality of water there are several parameters such as temperature, turbidity, pH, bacteria content, acidity and alkalinity.

water analysis can be classified into three categories according to the parameters that it measures:

1. Physical water analysis

2. Chemical water analysis

3. Microbiology water analysis.

Physical water analysis

Physical water analysis measures different physical parameters that may affect water quality which include:

Turbidity

Turbidity describes how cloudy the water is. High turbid water contains a high concentration of suspended solids and colloidal matter.

Which increases the cost of water treatment and can be hazardous to microorganisms and biota by clogging fish gills and lowering the concentration of dissolved oxygen.

There are two methods for measurements of turbidity in water:

Turbidity Meter Method

Turbidity meters analyze the turbidity of water samples using nephelometry (90-degree scattering) or other optical scatter-detection techniques.

There are different techniques and instruments to detect turbidity in water such as:

Light Scatter

Nephelometry

Attenuation

Ratio Designs

Turbidity Sensor Method

Turbidity sensors, like sample cells, employ optical technology to measure turbidity,

Nephelometry

Temperature Compensation

Backscatter

Attenuation

Solids in water analysis

Solids in water can be found as suspended solids, dissolved solids, or as colloidal depending on the size of the solids.

Water solids have a high impact on water quality as they affect water temperature, turbidity of the water and the level of dissolving oxygen.

Temperature

Temperature is a physical property that is used to determine and express how hot or freezing water is.

Temperature is an important parameter as it affects other properties of water such as water odor, the solubility of water, chemical reaction, viscosity and biological oxygen demand.

Odor and taste

water analysis is sociated with the presence of living microscopic organisms or decaying organic matter that contains weeds, algae; or industrial wastes containing ammonia, phenols, halogens and hydrocarbons.

Taste is resulted from fish, rendering them unpalatable.

While chlorination dilutes Odor and taste caused by some contaminants that are present.

It generates a moist odor itself when put in water that is polluted with detergents, algae and some other wastes.

Color analysis

Color analysis indicates the effectiveness of the water treatment system because water is colorless.

The presence of suspended particles and dissolved elements contribute significantly to the color of the water.

Electrical conductivity

Electrical conductivity is a measure of the ability of water to pass electric flow due to the presence of dissolved salts and inorganic materials.

Chemical water analysis

The chemical water parameter is the parameter that affects water quality but cannot be detected by using physical analysis such as water alkalinity, water acidity, chlorine, water pH and hardness.

PH analysis

PH is an indicator of the degree of acidity or alkalinity of a solution. Low pH causes corrosion in the presence of chlorine.

The pH of drinking water ranges from 6.5 to 8.5.

Hardness

Hardness is the amount of dissolved calcium and magnesium in the water.

Hardness occurs in the presence of compounds of calcium and magnesium, and a diversity of other metals.

Classification of water as calcium carbonate includes soft water, moderately hard water, Hard water and extremely hard water.

Dissolved oxygen

Dissolved oxygen is the level of free, non-compound oxygen that is present in water or other liquids.

It is an important parameter that is used to evaluate water quality because it affects the living organisms within a body of water.

Biological oxygen demand

Biological oxygen demand is the amount of oxygen that is required by microorganisms to break down biodegradable organic materials.

High biological oxygen demand indicates a high organic load in the water.

Biological water analysis

Biological water analysis is measured to monitor the existence of pathogens and microorganisms that are present in municipal water supply systems.

Bacteria

Bacteria are significant microorganisms in assessing water safety because bacteria such as E. coli are present in drinking water when the water source is contaminated with feces.

Algae

The growth of algae in water affects the quality of water in several ways.

As Algae causes characteristic color, odor and taste to water.

Also, algae prevent penetration of light to the bottom of the water system which impacts photosynthetic organisms.

Diverse algae produce toxic components.

Viruses

Human and animal waste is considered one of the sources of viruses that may be present in water and wastewater.

Viruses analysis of water is very important for keeping the public health of humans.

How does water analysis work?

There are four categories of typical low-tech, portable, field test methods for chemical water quality monitoring:

Test strips

Test strips are small, single-use strips that can change the color of the water to indicate the concentration of specific chemicals that are present in the water.

The user “energizes” the paper or plastic strip by soaking it in a water sample and rolling it around, or by holding the strip in a stream of water depending on the type of analysis.

After a short time, compare the test strip color with a color chart to read the concentration of the chemical.

These kits are extremely simple, but they are less accurate than other methods when users do not follow the instructions.

Color disk kits

Color disk test kits are available for most chemical tests.

The user puts a powder packet or drops of a liquid reagent to a water sample in a plastic tube that is used for analysis, then places the sample tube in a small plastic box.

This box includes a plastic disk with a color gradient printed on it.

The user rotates the color disk to determine the part that best matches the color of the sample, and then reads the concentration of the chemical from the disk.

Color disk kits are a little more complicated and costly, but more accurate due to multiple steps and often include prescribed wait times.

Laboratory testing kits

are the most effective method to adjust a wide range of water pollution problems.

The method is easy: you can order a sampling kit and then send the sample to the laboratory close to you and receive the results online.

Handheld digital instruments

Handheld digital instruments are useful to field technicians and are an essential part of any continuous or remote monitoring network.

Why is important to test the quality of water?

Monitoring of water is particularly important due to

Maintaining reliable and safe water sources and eliminating the potential health risks that are related to water

Treating the problem that is currently concerned with water quality.

Ensuring that water quality is isolated from any potential causes of contamination and suitable methods that are concerned with treatment systems.

References

[1] H2olabcheck, Thursday, 22nd November 2018, Why Is it Important to Test water? (online) available at https://www.h2olabcheck.com/blog/view/why-is-it-important-to-test-water

[2] Our laboratories, and types of water testing methods, (online) available at https://etrlabs.com/types-of-water-testing-methods/

[3] JESSICA ANNE LAWSON&PRATIBHA MISTRY, JULY 13, 2017, how to test water quality?Chemical tests for limited budgets, (online), available at https://blogs.worldbank.org/water/how-test-water-quality-chemical-tests-limited-budgets

[4] sensorsorex,09/20/2021, Three Main Types of Water Quality Parameters, (online) available at https://sensorex.com/2021/09/20/three-main-types-of-water-quality-parameters-explained/

[5] Water quality monitoring, standards, and treatment, (online) available at https://www.fao.org/3/x5624e/x5624e05.htm

[6] AOS Treatment Solutions, February 15, 2018, What Are Biological Water Quality Parameters? (online) available at https://aosts.com/what-are-biological-water-quality-parameters-indicators/

[7] Gaurab Karki, July 22, 2018, Biological parameters of water quality/ Biological characteristics of water, (online) available at https://www.onlinebiologynotes.com/biological-parameters-of-water-quality-biological-characteristics-of-water/

[8] water Science School, June 11, 2018, Hardness of Water, (online) available at https://www.usgs.gov/special-topics/water-science-school/science/hardness–water

[9] Fondest Environmental, Measuring Turbidity, TSS, and Water Clarity, (online) available at https://www.fondriest.com/environmental-measurements/measurements/measuring-water-quality/turbidity-sensors-meters-and-methods/#TurbidMM12