A water audit is a careful, step-by-step study of how water is used and wasted inside a home, school or locality. In this project, we collect data about water use, study it carefully, and find simple ways to reduce wastage of water.
5.1 What Will I Be Able To Do?
- Measure and calculate how much water is available, how much is used, and how much is wasted.
- Collect data on total water available and on the pattern of water use.
- Study and compare data related to water use.
- Find and apply simple, practical ways to reduce wastage of water.
5.2 What Will I Need?
| Category | Items |
|---|---|
| Recording | Notebook and pen, survey form for asking questions |
| Measuring | Measuring jar (or a 1 litre bottle as substitute), stopwatch or mobile timer |
| Plumbing tools | Wrench, spanner, pipes, plumbing consumables |
| Household items | Bucket, mug |
| Calculation tools | Calculator (mobile app can be used) |
| Technology | Computer with internet connectivity for research, spreadsheets and data analysis |
5.3 How Do I Keep Myself And Others Safe?
- Handling tools: Use plumbing tools carefully. Follow all safety rules for using tools.
- Outdoor safety: Always take permission before entering someone's home or property for a survey. Be careful around slippery places. Stay hydrated and avoid working in extreme heat.
- Internet safety: Ask a teacher for help while using the internet. Do not share personal information of yourself or anyone else. Use data only from trustworthy sources, such as government departments, official websites and national research institutes.
5.4 Water In India: A Big Challenge
India faces a serious water problem because water supply does not match the number of people who need it.
- India has only 4% of the world's freshwater but nearly 18% of the world's population.
- Water is not spread equally — some places face floods while others face droughts.
- Leaving a tap running for 5 minutes wastes 45 litres of water.
Droughts are usually seen as natural disasters, but they are actually caused mainly by human activities such as cutting down forests, poor farming methods, and taking out too much groundwater. Droughts also happen because of mismanagement and misuse of water — both at the micro level (a single household) and at the macro level (a district or state).
The good news is that many people's initiatives help save water — rainwater harvesting, recycling water and restoring old water bodies. The Government of India also runs programmes such as the Jal Jeevan Mission and Jal Shakti Abhiyan to give people access to water and help them save it through community participation.
5.5 What Do I Need To Know Before I Start?
To carry out a water audit, we need data. We collect primary data about water use in our own community, and secondary data about how much water is available and supplied.
5.5.1 Primary and Secondary Data
For a water audit, data collected must be:
- Correct and authentic — matches exactly what is being counted (eg: if counting red cars, no other colour is included)
- Reliable — even if two different people collect the same data, they get the same result
- Trustworthy — obtained through proper experiment or from a source that can be trusted
5.5.2 Units and Methods of Water Measurement
Water is measured in different units depending on the quantity:
| Unit | Used For |
|---|---|
| Millilitres (mL) | Very small quantities |
| Litres (L) | Household use (most common unit for water audit) |
| Cubic metres (m³) | Large quantities like municipal supply or water storage tanks |
Since using a graduated cylinder every time is not convenient, we use common household utensils (bottles, buckets, mugs) whose capacity in litres is already known, to measure daily water use.
To find the water flow rate of a tap or shower, we let water flow into a bucket for exactly one minute, and then measure how much water was collected.
5.5.3 Water Storage Capacity
The storage capacity of big water tanks in a locality can be calculated by using the dimensions marked on the tank — finding its volume and converting that into litres. This information can also be collected by talking to the water supply officer of the area, who can tell how much water is supplied to the locality.
5.5.4 Sources of Water
Rainwater reaches us through natural and man-made water sources such as rivers, wells, and borewells, and gets stored in tanks and dams. From dams or storage tanks, water reaches homes through canals and pipelines.
5.5.5 Collecting Data on Household Water Usage
Since it is not possible to collect data from every household in a locality, we select a few families (at least ten) and record their water use pattern in a form. The table below shows the information usually collected from a family.
| Information Collected | Details Recorded |
|---|---|
| Family details | Name of family, number of members |
| Water storage | Amount of water stored in the house per day (tanks, pots, vessels) |
| Washing clothes | Water used per day (washing machine cycles / number of buckets) |
| Washing utensils | Tap flow rate × average time spent washing |
| Drinking & cooking | Amount of water stored in bottles, number of bottles used |
| Bathing | Buckets used, or tap/shower flow rate × time used for bathing |
| Appliances | Water used by washing machine, RO filter, etc. |
| Other uses | Washing vehicles, gardening |
| Other water sources | Well, borewell, or purchased water |
| Leftover water | Whether unused stored water is recycled or thrown away |
| Water bill | Whether they receive a bill, and the approximate amount |
All collected data should be recorded in litres only, and then entered into a notebook or spreadsheet for analysis. Formulas in a spreadsheet (like SUM) can be used to add totals and calculate average consumption per person.
5.5.6 Estimating Rainwater Availability (Secondary Data)
This method helps us estimate how much rainwater is available in a geographical area using government data.
- Find the population of the district/town/village/ward.
- Find the area of the district/town in square kilometres, and convert it to square metres.
- Find the rainfall received in the year (usually given in mm), and convert it to metres.
- Calculate the total water received through rainfall.
- Divide the total rainwater among agriculture, industry and domestic use.
- Calculate rainwater available per person, per day, for domestic use.
(1 km² = 1,000,000 m² and 1 m³ = 1,000 L)
Generally, of the total rainwater received:
- 70% is required for agriculture (including farm animals)
- 20% is required for industry
- 10% is required for domestic consumption
Note that calculating water availability based only on a district's geography and rainfall does not always give an accurate picture, because rainwater flows into rivers, and the entire population living along a river — from where it starts to where it meets the sea — depends on that river's water, even if some areas along the way get less rainfall than others.
5.5.7 Comparing Water Consumption
After finding the average consumption per person using primary data, and the water availability using secondary data, we compare both with the amount of water the government recommends per person.
| Type of Data | What It Tells Us |
|---|---|
| Average consumption per person per day (primary data) | How much water your surveyed families actually use |
| Water available per person per day (secondary data / your calculation) | How much water is theoretically available for each person |
| Prescribed usage by Jal Jeevan Mission | 55 L/day for rural areas and 135 L/day for urban areas (as prescribed in 2025) |
Whenever secondary data is used, its source and the year of the data must always be mentioned, since information like population and rainfall keeps changing over time. For example: "The Government of India, through Jal Jeevan Mission, aims to provide 55 L of tap water per day for rural populations (Press Information Bureau, 14 Aug 2024)."
Ways in which water availability can be increased:
- Planting trees
- Reducing pollution to increase rainfall
- Reducing wastage of water
- Recycling water
- Water conservation methods like rainwater harvesting
5.5.8 Identifying Wastage Points and Amount of Wastewater
Common wastage points include dripping taps, wet patches under pipes, and overflowing tanks. Wastage can be measured using a bucket and a stopwatch — start the stopwatch when water begins to waste, stop it when the wastage ends, and note the duration and volume.
5.5.9 Reducing Water Wastage
Fixing a Leaking Tap — the general repair process followed by a plumber:
- 1Turn off the water mains before starting any repair work.
- 2Remove the tap's handle using a spanner or screwdriver.
- 3Unscrew the tap bonnet and remove the headgear to see the body washer, o-ring and jumper valve.
- 4Replace the worn-out body washer, o-ring and jumper valve with new parts, and apply lubricant to the spindle.
- 5Refit the bonnet and spindle carefully, without over-tightening the nuts.
- 6Put the tap back together, turn on the water mains, and check that the tap no longer leaks.
Reduce the use of water: Most people open a tap at full throttle out of habit. Water flow can be restricted using aerators or flow caps, which are simple devices fitted onto taps, or a tap can simply be opened only partially while using water.
5.5.10 Groundwater Recharge
Well water and borewell water are important sources of water, and storing water underground has an advantage — evaporation losses are minimal. But because of uncontrolled extraction, groundwater levels are falling in many areas. Rainwater can be helped to percolate into the ground using the following three principles:
5.5.11 Reusing Water — Greywater
Wastewater produced from domestic use like sinks, baths, washing machines and kitchens is called greywater. Instead of throwing it away, greywater can be reused for irrigation, cleaning, or even groundwater recharge.
Simple method: Runoff water from washing vegetables or from a washing sink (if not too soapy) can be used to water a kitchen garden.
Reed Bed Greywater System: This follows a natural filtration process, similar to how a flowing river cleans itself.
Greywater treated using such systems can be reused for purposes like flushing toilets, gardening, and cleaning.
5.5.12 Estimating Future Water Requirements
Once average consumption (primary data) and water availability (secondary data) are known, we can estimate future water needs for growing situations, such as a new housing society being built, or a college hostel starting nearby.
This helps in planning ahead, for example — estimating the extra water demand if a housing society of 100 homes (about 4 people per family) is built, or if a college hostel with 1,000 students starts operating nearby.
5.6 Water Audit Process — Overview
5.7 Think and Answer
- Hydrologist — studies the movement, distribution and quality of water
- Plumber — installs and repairs water pipes, taps and tanks
- Water Resource Manager — plans how water is distributed and conserved in a region
- Municipal Water Supply Officer — manages water supply for towns and cities
- Data Analyst — studies water usage data to find patterns and savings
- Agricultural Scientist — helps farmers use water efficiently for crops
- Civil Engineer — designs dams, canals, pipelines and water tanks
- Geologist — studies groundwater and underground rock layers
- Meteorologist — studies rainfall and weather patterns used in water planning
- NGO Worker — works on community-based water conservation projects