The water tank cleaning process, step by step

Why the method matters

The traditional way to clean a tank is to empty it, send a worker inside with a brush and a bucket, and scrub. It looks thorough, but it has real drawbacks. A person standing in your drinking water tank brings in whatever is on their feet and clothes. Thin plastic rooftop tanks can crack or deform under body weight. And underground sumps are confined spaces with poor air, where going inside is genuinely dangerous.

No-entry cleaning does the same job from outside: long suction hoses and a high-pressure jet lance go in through the lid or manhole, and nobody steps into the tank. It is also easier to show you the result, because every step is done in the open.

The 7 steps of no-entry tank cleaning

1. Inspect and take before photos. The crew checks the tank, the lid, the inlet and the outlet, and photographs the inside so you can see the starting condition.
2. Drain the tank. Leftover water is pumped out. If you want to keep it, it can be moved to your other tank (for example from the rooftop tank to the sump) instead of being wasted.
3. Sludge suction. A sludge pump pulls out the layer of silt, mud and settled dirt from the floor. This is the part that makes the biggest visible difference.
4. High-pressure jet wash. A jet lance strips algae, slime and scale off the walls, the floor and the underside of the lid, including corners a brush often misses.
5. Disinfect and flush. A food-safe disinfectant is applied, then the tank is flushed with clean water.
6. Remove rinse water and dry. The dirty rinse water is sucked out and the tank is left clean and dry before it is refilled.
7. After photos on WhatsApp. You get before and after photos, then you pay by UPI or cash. There is no advance.

How long it takes and how to prepare

A typical tank takes about 60 to 90 minutes. Larger sumps or very heavy sludge can take a little longer. To keep things smooth:

• Turn off the inlet or the motor the night before so the water level drops.
• Store a few buckets of water for the cleaning window if you need it for cooking or the toilet.
• Make sure the roof door and the sump manhole are accessible, and tell us in the booking notes which floor the tank is on.
• Keep a nearby drain or outlet free so dirty water has somewhere to go.

Once the tank is refilled, run each tap for a minute to clear the pipes. If the first water out of a tap looks a little cloudy, that is usually loose dust from the pipes and clears quickly.

Rooftop tanks vs underground sumps

The steps are the same for both, but the equipment and the setup differ a little.

Rooftop plastic tanks

We clean rooftop tanks from about 1,000 L up to 10,000 L and above. The jet lance works through the lid opening, so the tank walls are never stood on. Details are on the overhead tank cleaning page.

Underground concrete sumps

Sumps from about 3,000 L to 10,000 L and above are cleaned from the manhole with longer hoses and a stronger sludge pump. This is where no-entry matters most; our guide on underground sump cleaning safety explains why.

Cleaning the sump and rooftop tank on the same visit stops sludge from the sump being pumped straight back up to the roof.

Want to know the price for your tanks? Use the free quote form. We reply on WhatsApp with a fixed quote including GST before the visit, and you pay only after you have seen the after photos.

Questions