Table of Contents
Water tank cleaning in Dubai follows a clear rhythm in Dubai Municipality’s own guidance. Every water storage tank in a building should be emptied, cleaned and disinfected at least twice a year, inspected at least monthly with its covers intact and firmly in place, and cleaned by a company that Dubai Municipality has approved for that work. After the clean, a water sample goes to an accredited laboratory to confirm the result.
Those requirements come from two technical guidelines published by the Municipality’s Health and Safety Department, one on Legionella control in building water systems and the other on the quality of unbottled drinking water. Both apply to residential buildings as well as hotels, schools, commercial premises and labour accommodation. Both are published as open data, so an owner or facilities manager can read the source instead of relying on a contractor’s summary of it.
This page goes through what those documents say about the job itself and about the paperwork a building manager should keep afterwards. It also corrects two things an earlier version of this page got wrong.
At GRMC Pest Control, we work in villas, apartment towers and commercial premises across Dubai and Abu Dhabi, and standing water around tanks, pumps and overflow pipes is part of what we look at when mosquitoes keep coming back to a property. That earlier version told readers a professional clean would stop hair loss and improve their skin. We looked for a health authority that says so, found none, and have taken the claim out.
This guide sets out what water tank cleaning in Dubai involves under the Municipality’s guidance, so you can judge a contractor’s quotation and the documents they leave behind.
Water tank cleaning in Dubai at a glance
The short version, with each point taken from Dubai Municipality’s published guidance.
- How often: at least twice a year under both Municipality guidelines, and again whenever Legionella or other contamination is found. Both also ask for tanks to be inspected at least monthly, with all covers intact and firmly in place.
- Who does it: a water tank cleaning company approved by Dubai Municipality through its Food Safety Department. This approval is separate from the Municipality’s pest control listing.
- How it is disinfected: under the Legionella guideline, with a chlorine solution at 50 parts per million, added once the tank is three quarters full and left for at least four to six hours, then rinsed out before the tank is refilled.
- How it is checked: under the same guideline, with a water sample sent to an accredited laboratory at least 48 hours after refilling.
- What the building keeps: under the drinking water guideline, the cleaning and disinfection reports and the tank sample results, held for five years where there is no electronic records system, plus the cleaning contract.
- What a breach costs: AED 1,000 for violating health conditions related to cleaning drinking water tanks, according to the fines table in the Municipality’s drinking water guideline.
Why tanks in UAE heat need regular cleaning
A building tank holds water that has already left the public network and now waits in storage before anyone opens a tap. The trouble starts during that wait.
Water that sits
Dubai Municipality’s Technical Guidelines for Quality of Unbottled Drinking Water note that DEWA calculates the tank capacity for each building from the number of residents and the daily consumption rate, with storage sufficient for at least 24 hours of use. A tank is designed to hold water for a while. The Municipality’s Legionella guideline describes what happens next: once water from the public system enters a building, it “typically encounters warmer temperatures and is subject to low flow or stagnant conditions and a residence time that can lead to the loss of disinfectant residuals”.
Over the months, sediment settles on the tank floor and a film of microbes builds on the walls. The Legionella guideline describes a biofilm as “a thin layer of micro-organisms which may form as a slime on the surfaces in contact with water”, and it explains why that matters: “such biofilms, sludge and scale can protect Legionella bacteria from temperatures and concentrations of biocide that would otherwise kill or inhibit these organisms”.
That sentence is the case for physical cleaning. Adding chlorine to a tank with a layer of sludge on the floor treats the water and leaves the sludge, and whatever it shelters, in place. The drinking water guideline lists “settled sludge that supports the growth of microorganisms” among the conditions a building must reduce, and defines the cleaning job in plain terms: to “remove dirt, sediment, algae, or other contaminants from water tanks”.
Heat and Legionella
In the UAE, temperature is the factor that deserves the most attention. Dubai Municipality’s Technical Guidelines for Legionella Control in Water System state that Legionella has been found in water at temperatures between 6 °C and 60 °C, and that “water temperatures in the range 20°C to 45°C seem to favor their growth”. The World Health Organization gives a similar band in its legionellosis fact sheet, where the bacteria “live and grow in water systems at temperatures of 20 to 50 degrees Celsius (optimal 35 degrees Celsius)”.
That is why the Municipality asks for cold water to be kept below 20 °C throughout a building’s system, all the way to the outlets. Anyone who has run a cold tap in a Dubai villa in August knows how far a roof tank can drift from that. The drinking water guideline names uninsulated pipes, water stagnation and oversized storage tanks among the conditions that support microbial growth. Where a building cannot hold the cold water below 20 °C, the Legionella guideline advises considering “monitoring for Legionella and using a disinfection system if Legionella is not under control”.
Legionella matters mainly through what people breathe. The WHO states that “the most common form of transmission of Legionella is inhalation of contaminated aerosols from contaminated water”, and in a home the obvious source of fine spray is the shower. The same fact sheet notes that no direct human-to-human transmission has been reported.
What cleaning will not do
The earlier version of this page claimed that a professional clean would stop hair fall and “instantly” improve skin. We could not find a health authority that supports either claim. Dubai Municipality’s drinking water guideline deals with microbial contamination, chemical limits and aesthetic qualities such as taste, smell and colour, all measured against the UAE standard for unbottled drinking water. It makes no claim that tank cleaning changes hair or skin.
There is a practical reason as well. Cleaning removes what has settled in the tank and grown on its walls, and it leaves the dissolved content of the water arriving from the network as it was. The Municipality treats that as a separate subject, listing water softeners, deionisers, activated carbon and filtration as treatments chosen according to “the source of the water entering the building”. If hair or skin is the worry, a doctor or dermatologist is a better first call than a tank contractor.
What a proper clean involves, step by step
The current edition of Dubai Municipality’s Legionella guideline, issued on 19 August 2025, sets out the tank procedure step by step. A competent contractor’s method statement should look much like it.
Before the day
The guideline asks for a risk assessment and a written plan first, and for building occupants and maintenance teams to be told about “cleaning procedures and any disruptions to the water supply”. Warning signs go up in all water-use areas while disinfection is under way. In a tower, that notice normally goes out through the facilities manager. In a villa community, it usually also means arranging a gate pass for the contractor’s vehicle and choosing a morning when nobody in the house needs a shower.
If a tank is in very poor condition, the guideline calls for pre-disinfection before the crew starts work inside it, to protect the cleaners’ health. The same section lists gloves, eye protection and masks as the protective equipment the crew should be wearing, which is worth remembering if a quotation says nothing about safety.
On the day
The Municipality’s sequence for the tank itself runs in this order.
- Empty the tank: all the water is drained before cleaning starts.
- Clean the walls and floor: with a soft brush and clean water, using approved cleaning products only where deposits are stubborn. The earlier edition of the guideline adds that the method should not damage the tank’s coatings.
- Rinse: several times, until the chemicals and sediment are gone.
- Disinfect: under the guideline, the tank is filled to three quarters of its capacity, a chlorine solution at 50 parts per million is added and stirred through, and the water is left for at least four to six hours.
- Rinse again and refill: the chlorine residue is rinsed out, the tank is refilled with clean water, and it is checked for leaks.
- Test: the guideline calls for a sample to go to an accredited laboratory at least 48 hours after refilling.
Two details in that list are worth holding a contractor to. The Municipality’s method names a soft brush and clean water, so if a quotation leads on high-pressure blasting, as the older version of this page did, ask the contractor how that fits the guideline. The disinfection is also a timed soak, so a crew that drains, sprays and refills inside an hour has skipped the step that does the disinfecting.
The tank is only part of the system. The same guideline treats the building’s pipework as its own job, disinfected with chlorine at 1 to 2 ppm, and its checklist asks for the hot and cold water system to be disinfected at least twice a year so that a free chlorine residual of 1 to 2 mg/l holds for an hour, with each outlet run for at least five minutes. A quotation that covers the tank alone leaves that part out.
After the clean
The laboratory result is what shows the clean worked. The Legionella guideline puts the sample at least 48 hours after refilling. The drinking water guideline lists a sample a week after each regular six-monthly clean, plus periodic samples at least every six months, taken by a laboratory accredited by the Emirates International Accreditation Centre (EIAC) and tested against the UAE standard for unbottled drinking water, UAE.S GSO 149:2021.
In normal use, the drinking water guideline expects free chlorine at the point of delivery of 0.2 to 0.5 ppm, and it cites the World Health Organization’s health-based limit of 5.0 mg/l for chlorine. A faint chlorine smell in the days after a clean is therefore not in itself a cause for alarm. Water that smells strongly of chlorine suggests the residue was not fully rinsed out, which the procedure requires, and is worth raising with the contractor.
The paperwork a building manager should ask for
Most of the confusion sits here, because the word “certificate” gets used for several different documents.
The company’s tank cleaning approval
The drinking water guideline states that the water tank cleaning company “must be approved by Dubai Municipality”, and names the Food Safety Department’s Registration and Permit Section as the approving office. The Municipality’s published description of that approval service, which dates from 2020, says it is open only to Dubai companies licensed for a tanks, containers and crates cleaning activity. The company registers on the FoodWatch platform, submits a Water Tank Cleaning Manual covering its staff, their health status, its disinfectants and its procedures. The same service description says the approval is valid for one year.
Ask to see that approval and check the date on it. We did not find a published register of approved tank cleaning companies comparable to the Municipality’s pest control list, so the approval document itself is the thing to check.
One point trips people up. A place on Dubai Municipality’s list of approved pest control companies comes from a different office, the Public Health Pest Control Section, and it covers pest control work. It says nothing about tank cleaning. We explain how that list works in our guide to Dubai Municipality approved pest control. A company can hold one approval without the other, so ask about each one separately, whoever the company is.
The report from the job
The cleaning company must “prepare and save cleaning and disinfection reports that include chemicals used, methods of use, mechanism of cleaning and disinfection”, according to the drinking water guideline. Ask for that report in writing at the end of the job, together with the Material Safety Data Sheet for each product used, which the Legionella guideline lists among the records a building keeps.
The Legionella guideline’s checklist also expects a valid “water tank cleaning and disinfection certificate” on file. The guidance does not describe it as a document the Municipality issues itself, and it places the reporting duty on the approved company. An earlier version of this page promised “the official DM Cleaning Certificate”, and we have removed that wording because it described something we could not verify.
What the building keeps, and what happens if it does not
The drinking water guideline lists the building’s records: water tank cleaning reports, periodic disinfection reports, the contracts for cleaning and disinfecting the tanks and the wider system, inspection results and laboratory results. Under the same guideline, monitoring data is kept for at least two years, and reports from the inspection and cleaning companies and tank samples for five years where there is no electronic system. For buildings covered by the Legionella guideline, the required reports also go to the Municipality online, through its Building Health and Safety compliance e-services.
If an inspector finds a problem, the drinking water guideline says the party is first alerted and given a time limit to put it right, and fines and legal measures follow if the correction is not made. Its fines table sets AED 1,000 for “violating health conditions related to cleaning drinking water tanks” and AED 1,000 for companies working in tank cleaning that breach health conditions. The same table sets AED 20,000 for practising an activity covered by the relevant local order without a permit from the competent department, which is one more reason to see the contractor’s approval before the work starts.
The habit of checking a contractor’s paperwork is the same whatever the trade. Our guide to choosing a pest control company in Dubai sets out how we would check one before letting them onto a property.
Tanks, pump rooms and pests
This is the part of the subject that sits squarely in our own line of work.
Dubai Municipality’s drinking water guideline says unbottled drinking water “must be completely free from algae, fungi, insects, their larvae, or its egg sacs”, and both guidelines insist that tank covers stay intact and fixed in place. A cracked lid, a hatch left ajar after a maintenance visit or an overflow pipe without a screen gives mosquitoes access to standing water where they can lay eggs. The World Health Organization’s dengue fact sheet makes the same point about household water storage, advising people to “cover, empty and clean domestic water storage containers on a weekly basis”.
A building tank cannot be emptied every week, which is why the cover matters so much. Around the tank, check the overflow outlet, the drip tray under the pump and any water pooling on the plant room floor, since water collects in those spots unnoticed. Our guide to mosquito and fly control for Dubai villas covers the rest of the property, from balconies to garden irrigation.
Pump rooms and tank enclosures are also warm and damp, and few people go into them, which suits cockroaches and rodents. If you are seeing mosquitoes, cockroaches or rodents around the tank room, that is pest control work, and our mosquito control service starts with finding where the water is sitting. Pest treatment from GRMC in the UAE comes with our 100% Pest-Free Or Money Back offer: if the pest is still there after the treatment and the follow-up visit, you get your money back.
What affects the price
We have left prices off this page until we can publish current figures with the scope attached. These are the points that move a quotation up or down.
- Number of tanks: many villas have a ground or underground tank as well as a roof tank, and each one is its own job.
- Access: a roof hatch, a confined underground tank or a tower that restricts contractor work to set hours all change the crew and the time needed.
- The laboratory test: whether sampling and a report from an EIAC-accredited laboratory are in the price or billed separately.
- Condition: a tank that needs pre-disinfection before the crew can safely work inside it is a longer job.
- Pipework: whether the building’s internal network is disinfected as well as the tank.
Compare quotations on those points before the headline figure, and get the agreed scope in writing.
Frequently asked questions
How often should water tanks be cleaned in Dubai?
Dubai Municipality’s technical guidelines on Legionella control and on unbottled drinking water both say water storage tanks should be emptied, cleaned and disinfected at least twice a year. The same guidelines ask for tanks to be inspected at least monthly with all covers intact, and for extra cleaning and disinfection if Legionella or other contamination is found.
Who is allowed to clean water tanks in Dubai?
Dubai Municipality’s drinking water guideline states that the water tank cleaning company must be approved by Dubai Municipality, and names the Food Safety Department’s Registration and Permit Section as the approving office. That approval is separate from the Municipality’s pest control listing, so ask to see the tank cleaning approval itself and check that it is in date.
What documents should I get after water tank cleaning?
Ask for the company’s cleaning and disinfection report, which Dubai Municipality’s drinking water guideline says must include the chemicals used and the cleaning and disinfection method, together with the Material Safety Data Sheets for the products. You should also receive a laboratory result for a water sample, which the Municipality’s Legionella guideline says should be taken at least 48 hours after the tank is refilled.
What is the fine for not cleaning a water tank in Dubai?
The fines table in Dubai Municipality’s Technical Guidelines for Quality of Unbottled Drinking Water, issued in September 2024, lists AED 1,000 for violating health conditions related to cleaning drinking water tanks. The same guideline says a party is first alerted and given a time limit to correct the problem, and that fines and legal measures follow if it does not.
How long does water tank cleaning take?
Dubai Municipality’s Legionella guideline asks for the chlorine solution to stay in the tank for at least four to six hours, so the disinfection step alone takes most of a morning, before draining, cleaning, rinsing and refilling are added. Ask the contractor for a written timetable, and plan for the water supply to be interrupted while the work is under way.
Is the chlorine used in water tank cleaning safe?
Dubai Municipality’s Legionella guideline disinfects the tank with a 50 ppm chlorine solution and then requires a thorough rinse to remove all chlorine residues before the tank is refilled. In normal use, the Municipality’s drinking water guideline expects free chlorine at the point of delivery of 0.2 to 0.5 ppm, well below the World Health Organization health-based limit of 5.0 mg/l for chlorine that the same guideline cites.
Can a dirty water tank cause hair loss?
We found no health authority that links tank cleaning to hair loss, and Dubai Municipality’s drinking water guideline makes no such claim. Cleaning removes sediment, biofilm and other contaminants that have built up inside the tank, and it leaves the minerals dissolved in the building’s water supply unchanged. If hair fall is the concern, a doctor or dermatologist is the right first step.
How much does water tank cleaning cost in Dubai?
The price depends on how many tanks there are, where they sit and how easy they are to reach, their condition, and whether the laboratory test and the pipework disinfection are included. Compare quotations on scope before the headline figure, and check that the company holds Dubai Municipality’s water tank cleaning approval before comparing prices at all.
Applying the same standard to us
GRMC appears on Dubai Municipality’s list of approved pest control companies, in the August 2026 edition, at entry 135 of the general list in Group C. That listing covers general pest control. It is not a water tank cleaning approval, which comes from the Food Safety Department as described above.
Whoever you book, ask for the tank cleaning approval, the method statement and the laboratory arrangements before the day, and the written report after it. That applies to us as much as anyone else.
Abu Dhabi falls outside this page. Dubai Municipality’s guidance covers Dubai, and properties in Abu Dhabi answer to that emirate’s own authorities, so check the requirements there before booking any tank work.
If mosquitoes, cockroaches or rodents keep turning up around your tank room or pump room, Contact GRMC Pest Control to book an inspection of the tank area and plant room in Dubai or Abu Dhabi.
Details on this page were checked on 21 September 2026 against Dubai Municipality’s Technical Guidelines for Legionella Control in Water System (DM-HSD-GU44-LCWS2, version 6, issued 19 August 2025, with one detail from the earlier version 3), its Technical Guidelines for Quality of Unbottled Drinking Water (DM-HSD-GU17-DW2, version 1, issued 25 September 2024), its published description of the water tank cleaning company approval service, and the World Health Organization’s fact sheets on legionellosis and dengue. Guidelines are revised, so check the current edition before you rely on it.
