Water Tank Size Calculator
Find the perfect overhead or underground water tank storage capacity and dimensions for your home or office building.
Sizing Parameters
Recommended Storage
Standard Tank Capacity
Calculated net requirement: 0 Litres (+20% safety margin)
In Gallons (US)
0 Gal
Equiv. 20L Water Jars
0 Jars
Estimated Tank Dimensions
Water Tank Deliveries Management
Do you manage multi-unit properties or rely on private water tankers? Keeping accounts of municipal supply, borewell opex, and commercial tankers is highly challenging.
Are you a water supplier?
Use PaniHisab to track custom tanker trips, bill clients by volume, and manage daily operations.
Water Tank Kitna Bada Chahiye? Indian Household Storage Guide
Building or renovating a house involves many crucial decisions, and one of the most common plumbing questions is: water tank kitna bada chahiye (how big should the water tank be)? Finding the correct overhead or underground sump capacity is essential. If the tank is too small, you will suffer from frequent water shortages; if it is too large, you lock capital, waste roof space, and risk water stagnation. Our water tank size calculator is custom-built for Indian households to provide accurate volumetric requirements and physical dimensions.
According to Indian Standard Code IS 1172, a typical resident in an urban home requires 135 Litres Per Day (LPD) for all activities. However, because municipal supplies in Indian towns are often intermittent (supply comes only on alternate days or once in 3 days), having sufficient storage buffer is critical.
Standard Water Usage Breakdown in India (IS 1172)
| Purpose | Standard Consumption (LPD) | Percentage (%) |
|---|---|---|
| Bathing | 55 Litres | 40.7% |
| Toilet Flushing | 30 Litres | 22.2% |
| Washing Clothes | 20 Litres | 14.8% |
| Washing Utensils | 10 Litres | 7.4% |
| House Cleaning | 10 Litres | 7.4% |
| Cooking | 5 Litres | 3.7% |
| Drinking | 5 Litres | 3.7% |
Why include a safety margin?
In many Indian cities, municipal water supply is irregular and may only come once in 2 or 3 days. A safety margin of 20% accommodates minor leakage, evaporation losses, and unusual peaks (such as guest visits or deep cleaning days).
Overhead vs Underground Tanks
Underground sumps should ideally be 1.5 to 2 times the capacity of overhead tanks. The underground sump acts as a primary buffer from municipal tankers/lines, which is then pumped to the overhead tank for gravity-based distribution.
Calculations for Tank Dimensions: Cylindrical vs. Rectangular
Knowing the volume in Litres is only step one. Builders and plumbers need physical dimensions to construct concrete sumps or install overhead PVC tanks.
- Cylindrical PVC Tanks: Volume $V = \pi r^2 h$. For a standard 1,000 Litre tank, our calculator models an aspect ratio where height is roughly 1.2 times the diameter, providing a stable footprint. This translates to about 1.1 meters in diameter and 1.3 meters in height.
- Rectangular Sumps: Underground concrete sumps are rectangular. Volume $V = Length \times Width \times Depth$. We model a standard proportion where Length is 1.5 times the Width, and Depth equals Width, ensuring optimal mechanical stability.
How Water Suppliers and Tankers Connect via PaniHisab
If your area suffers from low groundwater table or irregular municipal piping, you likely rely on commercial **water tanker deliveries** to fill your sumps. Managing tanker deliveries and billing can be difficult for both housing societies and tanker agencies.
This is where PaniHisab helps. Water tanker agencies use the PaniHisab mobile app to record daily trips, log filled capacities (such as 5,000L or 10,000L tankers), and send instant invoice reminders to housing society administrators.
If you are starting a water distribution business or tanker agency and want to understand capital setup details, read our complete guide on water supply business investment.
Frequently Asked Questions (FAQ)
What is the standard water requirement per person per day in India?
As per Bureau of Indian Standards (BIS) IS 1172, the minimum water requirement for a household with full flushing systems is 135 Litres Per Day (LPD) per person. In rural areas or low-income settings, this can range from 40 to 70 LPD.
How do you convert water tank volume from Litres to Gallons?
To convert Litres to US Gallons, divide the volume in Litres by 3.785. For example, a 1000L tank is equal to approximately 264 US Gallons.
How big should an underground sump tank be compared to the overhead tank?
Ideally, your underground sump should hold at least 1.5 to 2 times the volume of your overhead tank. This acts as a reliable storage buffer during municipal supply gaps.