The short answer, by property type, followed by what the law actually says, which is probably not what you have heard.
The short answer
| Property type | Recommended frequency |
|---|---|
| Domestic households | Every 3–6 months |
| Commercial establishments | Every 3 months |
| RWAs / apartment complexes | Quarterly |
| Hospitals / clinics | Quarterly, minimum |
| Restaurants / cloud kitchens | Quarterly, aligned with FSSAI inspection cycles |
These are Ozone Wash™'s operational recommendations, based on how quickly sediment, biofilm and bacterial regrowth typically occur in Hyderabad's water conditions, they are not, on their own, a fixed legal mandate. That distinction matters, so let's be precise about what the law actually says.
What GHMC law actually requires
You may have heard that Hyderabad municipal law mandates tank cleaning on a fixed schedule. Here's the precise, verified answer: Section 506 of the Greater Hyderabad Municipal Corporation Act, 1955 gives the Commissioner the power to order the cleansing of any private water source, spring, tank, or well, used for drinking, if it's found to be insanitary. It's an enforcement provision that applies case-by-case, not a fixed calendar requirement written into the Act itself. In other words: the law doesn't say "every 3 months," but it does give the authorities real power to act if your tank becomes a problem, which is exactly why staying ahead of it with a regular schedule matters, GHMC mandate or not.
What actually happens if you skip cleaning
- Sediment and rust particles accumulate at the tank base, visible as discoloured water when the tank is disturbed.
- Biofilm: a bacterial layer that scrubbing alone can't fully remove, builds up on tank walls.
- Algae growth accelerates in warmer months if any light reaches the tank interior.
- Contamination risk compounds after monsoon, when runoff and municipal supply disruptions are more likely.