The WQI is calculated by averaging the individual index values of some or all of the parameters within five water quality parameter categories:
Table of Contents
How is Wqi value calculated?
The WQI is calculated by averaging the individual index values of some or all of the parameters within five water quality parameter categories:
- Water clarity: turbidity (NTU*) and/or Secchi disk depth (meters or feet);
- Dissolved oxygen: Dissolved oxygen concentration (mg/l);
What is a Wqi test?
This index, known as the Water Quality Index, or WQI, consists of nine tests to determine water quality. These nine tests are: temperature, pH, turbidity, total solids, dissolved oxygen, biochemical oxygen demand, phosphates, nitrate, and fecal coliform.
How is Wqi calculated Malaysia?
WQI = 0.22(siDO) + 0.19(siBOD) + 0.16(siCOD) + 0.15(siAN) + 0.16(siTSS) + 0.12(sipH) 621 Page 3 siDO-subindex is for dissolved oxygen, siBOD-subindex is for biochemical oxygen demand, siCOD-subindex is for chemical oxygen demand, siAN-subindex is for ammoniacal-nitrogen, siTSS-subindex is for total suspended solid.
What does Wqi stand for?
The Freshwater Quality Index, sometimes called the WQI, summarizes and presents water-quality data as a number ranging from 1 to 100, with a higher number indicating better water quality. The WQI can be found on individual station pages in the Freshwater Information Network data application.
What Wqi value indicates water quality?
91–100
4. Water quality index calculation
| WQI value | Ratings of water quality |
|---|---|
| 91–100 | Excellent |
| 71–90 | Good |
| 51–70 | Medium |
| 26–50 | Bad |
What is a good Wqi score?
WQI scores from 80-100 indicate high water quality, meaning that water quality rarely exceeds guidelines, and if so, only by a narrow margin. WQI scores from 70-79 indicates fair or marginal water quality that sometimes exceeds guidelines, possibly by a wide margin.
How is Wisconsin water quality index calculated?
WQI = ∑ SIi (4) SIi is the subindex of ith parameter; qi is the rating based on concentration of ith parameter and n is the number of parameters. The computed WQI values are classified into five types, “excellent water” to “water, unsuitable for drinking”.
What is dissolved oxygen do?
Dissolved oxygen (DO) is the amount of oxygen that is present in water. Water bodies receive oxygen from the atmosphere and from aquatic plants. Running water, such as that of a swift moving stream, dissolves more oxygen than the still water of a pond or lake.
What is the water quality index of India?
120th among 122 countries
Globally, India is ranked 120th among 122 countries in WaterAid’s water quality index….Quality of water in India’s state capitals.
| City rankings as per water quality tests conducted by Bureau of Indian Standards | Catagorisation/Rank | 2 |
|---|---|---|
| Capital | Bhubaneshwar | |
| Number of samples failing | 1/10 | |
| No of individual parameters of samples failing | 1 |
How is water quality index calculated in India?
The Criteria for Calculating Water Quality Index (WQI) is illustrated below –
- Dissolved oxygen : < 4.0 mg/l.
- Biological Oxygen Demand : > 3.0 mg/l.
- Faecal Coliform : > 2500 MPN/ 100 ml.
- Total Coliform : > 5000 MPN/ 100 ml.