In this article we will look at the most frequently asked questions about the water analysis.
Reasons why you should do the water analysis?
The water testing is recommended in the following cases:
- if you want to know the condition of your tap or well water and make sure that it does not contain dangerous and toxic substances;
- if you plan to set up the equipment for the water purification (water analysis is necessary to choose the most suitable cleaning system);
- if you want to make sure that your water treatment equipment is working efficiently;
- if you plan to buy a house or a land.
Where to do a qualitative water analysis?
Laboratory testing of drinking water must be performed in an accredited laboratory. Accredited laboratories are competent to perform the drinking water testing, guarantees full-fledged, high-quality water research and also ensures the reliability of the obtained test results. In Latvia the institution that are responsible for the accreditation of laboratories is the Latvian National Accreditation Office. The register of accredited laboratories is available here.
How to collect a water sample correctly?
The results of analytical studies of the water quality will be correct only in case the water sample is collected correctly.
- It is necessary to prepare a clean polyethylene bottle. Do not use flavored beverage containers.
- Open the water tap and wait 10 – 15 minutes.
- Fill the container with the water as full as possible. Use a small stream of the water, direct it towards the wall of the bottle.
- Before closing the cap slightly squeeze the bottle to reduce the air content in the sample.
- Take a marker and write on the bottle the date, time and place of sampling.
- Take the water sample to the laboratory. Try not to store it for more than 12 hours. If long-term transportation is required, it is recommended to store it in the refrigerator.
For the study of microbiological indicators it is worth inviting a laboratory technician to collect a sample or use a special sterile container.
These rules apply when taking water samples from a well as well as from a water supply.
What indicators should be examined?
The regulation Nr.671 “Dzeramā ūdens obligātās nekaitīguma un kvalitātes prasības, monitoringa un kontroles kārtība” Appendix 2 defines the drinking water quality indicators and maximum permissible values in Latvia.
To make sure the water is safe for consumption:
- it is enough to analyze the following indicators: nitrates, aluminum, electrical conductivity, pH (hydrogen ion concentration), ammonium, total hardness, iron, chlorides, sulfates, manganese, permanganate index (oxidability).
- it is not necessary to examine the amount of heavy metals and trihalomethanes (this also applies to microbiological indicators).
The price of the water quality analysis depends on the price list of the selected laboratory.
Additional factors that must be taken into account when evaluating the water quality are also the characteristic of the water due to its geographical location, the presence of industrial enterprises etc.
How often to do a water analysis?
For tap water it is advisable to do the water analysis once a year. But for the well water twice a year- in spring (during the floods) and in summer time (during the flowering of reservoirs).
How to interpret the results of the water analysis?
Some of the most frequently analyzed indicators in the water analysis are:
- Smell: characterizes the origin of the water. It can be used to evaluate the presence of certain impurities (e.g. hydrogen sulphide).
- Turbidity: determines the amount of suspended particles (sand, clay, silt, etc.).
- Color: indicates the presence of organic substances of natural origin.
- Electrical conductivity: characterizes the material’s ability to conduct electric current. If there are more salts or other compounds dissolved in the water, the higher is electrical conductivity.
- Hardness: shows the total amount of calcium and magnesium salts.
- Nitrates: indicates a high concentration of sewage or fertilizers.
- Permanganate index (oxidability): characterizes the level of general organic pollution.
- pH level (hydrogen ion concentration): perfectly pure water has a pH of 7 and is neutral. A pH below 7 means that the environment is acidic, a pH above 7 means that the environment is alkaline.
- Ammonium: an increased amount of ammonium in the water indicates to possible bacterial, sewage and animal waste pollution.
- Iron: an increased concentration of iron causes changes in the taste and appearance of the water, contributes to the corrosion of pipes in water supply networks and creates conditions for the growth of specific bacteria.
- Chlorides: too much chloride in drinking water is a sign of excessive water salinity.
- Sulfates: an increased concentration of sulfate ions in drinking water (>250 mg/l) gives the water an unpleasant taste as well as reduces the effectiveness of the water disinfection.
- Manganese: if the concentration of manganese is more than 0.1 mg/l, changes the taste, color and smell of the water . Forms brown and black sediments.
In each report of the water analysis results there are names of the parameters, numerical results of the parameters and normative values. Based on them it is possible to make conclusions about the water quality, determine possible problems and solutions.
If you have any questions about the water analysis, the process of making them and the results of the analysis, contact us and our consultants will provide you with all the necessary information.