Category: Commercial & Institutional Property

In a house, the answer to who cleans the water tank is obvious. In a block of flats it is the question nobody wants to own. The tenant says it is the landlord’s job, the landlord says it is the union’s, the union says there is no money, and the builder left years ago. Meanwhile forty families drink from the same tank.

This article sets out apartment water tank responsibility in Karachi as it works in practice: who holds the duty in each kind of building, what each party can do, and how to get a shared tank cleaned without a fight. It is general guidance, not legal advice. Your sub-lease, tenancy agreement and the union’s own rules decide the detail.

The short answer

Your situation	Who is normally responsible for shared tanks	Who pays
Owner-occupier in a building with a union or association	The union, as manager of common areas	All owners, through maintenance charges
Tenant in such a building	The union; your landlord is the member and pays the charges unless your agreement passes them to you	Per the tenancy agreement
Building still controlled by the builder	The builder, until common areas are handed over	Builder, usually recovered through maintenance charges
Building owned by one landlord	The landlord	Landlord, unless agreed otherwise
Portion in a divided bungalow	The owner of the bungalow	Owner, sometimes shared with tenants
A tank that serves only your flat	You, or your landlord under the tenancy	As agreed

The principle behind the table is simple: the party that controls the common areas, collects the maintenance money and holds the keys to the tank room and roof is the party that should arrange the cleaning.

How water works in a Karachi apartment building

Most blocks have an underground tank that fills from the line, from tankers or from a borehole. Pumps lift the water to one or more rooftop tanks, and gravity feeds the flats. Everything is shared. Supply to the city is intermittent and short of demand, as explained in our guide to KWSB water supply, so buildings buy tanker water regularly and store several days’ worth.

The consequences of that arrangement are predictable:

• One contaminated fill, or one dead bird in a roof tank, reaches every household.
• Heavy pumping keeps sludge stirred up.
• Roofs are used for drying clothes, storage and dish antennas, and tank covers get moved, broken or left off.
• Nobody sees inside the underground tank from one year to the next.
• When there is a main line failure, such as the University Road burst of late 2024, the first dirty flow lands in the shared tank.

Local conditions in the city’s densest apartment districts are described in water tanks in Gulshan and Johar.

Apartment water tank responsibility in Karachi, case by case

If you rent your flat

You have two relationships: with your landlord, under the tenancy agreement, and through him with the building. You cannot instruct the union directly, but you can ask your landlord to raise the matter, and you can speak to the union office yourself as a resident. Check what your agreement says about maintenance charges. Whoever pays them, the service they fund should include the tanks.

If you own your flat

You own your unit and a share in the common property, which includes the tanks, pumps and pipes. You are entitled to ask how the maintenance fund is spent and to see records of tank cleaning. If the union is inactive, owners can still act together: agree a date, collect the contribution and appoint a contractor.

If the builder still runs the building

Until a builder hands over the common areas to the residents, he remains responsible for running them, usually while collecting maintenance charges. Ask in writing for the cleaning schedule and the last report. If handover is overdue, that is a wider issue for the owners to pursue with legal advice.

If you live in a portion

A bungalow divided into two or three portions normally shares one underground and one rooftop tank. The owner controls them. If the owner lives elsewhere, the tenants should agree among themselves, tell the owner what is needed, and propose splitting the cost if that gets it done.

If your flat has its own tank

Some flats have a private rooftop tank or drums fed from the shared system. Those are yours to keep clean, and they should be included whenever the building’s tanks are done.

What a neglected shared tank does

The health risks are the same as for any dirty tank, multiplied by the number of households. They are set out in waterborne disease in Karachi. In a building, the tell-tale sign is illness or bad water in several flats at once. Other signs are listed in ten signs your water may be making you sick.

There is a safety risk too. Unions sometimes send the chowkidar or a labourer into the underground tank to save money. Closed tanks can hold gas and too little oxygen. In June 2025, five men died in an underground water tank in Karachi, three of them trying to rescue the others. A union that sends an untrained man down is taking that risk on behalf of every resident.

How to get a shared tank cleaned: seven steps

1. Find out the facts. Ask the union or caretaker when each tank was last cleaned, by whom, and whether there is a report.
2. Look for yourself. Check the roof tank covers, and look into the tanks from above with a torch. Do not climb in.
3. Get a written quote from a professional contractor, based on a survey of the building.
4. Put a proposal in writing to the union or in the residents’ group: the date, the cost per flat, what residents need to do on the day.
5. Collect contributions or agree payment from the maintenance fund.
6. Plan the day. Choose a time just before the supply turn, when the underground tank is low, and tell residents to store a few buckets.
7. Keep the report in the union’s file and post the next cleaning date on the notice board.

A proposal with a date and a price is hard to ignore. A complaint is easy to ignore.

What each party can do now

Tenants

• Ask your landlord and the union for the last cleaning date
• Boil or filter drinking water whatever the answer; a filter and a clean tank do different jobs, as set out in water filter versus tank cleaning
• Offer to pay your share if that removes the obstacle
• At renewal, ask for a line in the agreement about tank cleaning

Owners and committee members

• Add tank cleaning to the annual maintenance budget as a fixed item
• Fix the dates for the year: every three months for shared tanks
• Appoint one committee member to hold the reports
• Replace broken covers and keep the roof tank area locked or at least tidy
• Never allow staff to enter the underground tank

Landlords

• Pay maintenance charges on time and ask what they cover
• Give incoming tenants the latest cleaning report
• For buildings you own outright, set a schedule yourself. Our guide for property managers has a maintenance calendar and suggested tenancy wording.

How often should a building’s tanks be cleaned?

Every three months for shared tanks, and straight away after flooding, a sewage leak, a main line failure that brought dirty water, or illness in several flats. The Sindh health department’s minimum for any tank is once a year before summer. The reasoning behind the intervals is in how often to clean a water tank in Karachi.

What a professional cleaning involves in a building

We survey the building first, free of charge, and quote in writing. On the day, the work follows our eight-step procedure: controlled drainage, ventilation and a gas check before anyone enters the underground tank, jet washing at 3,000+ PSI, vacuum extraction of sludge, disinfection, rinse and inspection. An underground RCC tank takes four to eight hours and each rooftop tank two to four. Where there are two rooftop tanks they can be cleaned one after the other so the building is not left dry.

The union receives a dated report with photographs from inside each tank, a recommended next date and a numbered SRB/FBR tax invoice for its accounts. What to look for in any contractor is covered in what to ask before hiring a tank cleaning company.

Our building and flat tank cleaning teams

Apartment buildings in Gulshan-e-Iqbal, Gulistan-e-Johar, Federal B Area, North Nazimabad and the rest of the east and centre are handled by our Gulshan and Jauhar branch on 0340 2717530. Buildings in DHA, Clifton and the south are handled by our DHA and Clifton branch on 0333 0293174. Residential projects named on our clients page include Shamir Residency. If your flat has its own tank, the online calculator gives an instant price.

Frequently asked questions

My landlord refuses to get the tank cleaned. What can I do?

If it is a shared tank, the landlord may not be the right person: approach the union with other residents. If the landlord owns the whole building, put the request in writing with a quote, offer to share the cost, and raise it at renewal. For anything beyond that, take legal advice on your tenancy agreement.

Can a single flat owner arrange cleaning of the shared tank?

Not alone, because it is common property. You need the union’s consent or the agreement of the other owners.

We have an underground tank and rooftop tanks. Do all of them need cleaning?

Yes, on the same visit. Cleaning one and not the others lets the dirty tank recontaminate the clean one.

How much does it cost per flat?

It depends on the number and size of tanks. Divided across the households and spread over the year it is a small part of the maintenance charge. Ask for a survey and a written quote.

How do we know the job was done properly?

Ask for the photographs. The floor and corners of each tank should be visibly clean in the after pictures, and the report should be dated and signed.

Is there a tank cleaning service for whole buildings as well as single flats?

Yes. We clean shared underground and rooftop tanks for apartment buildings after a free survey, and individual tanks for single flats and houses.

Our union has no funds. What then?

Collect a one-off contribution per flat for the first cleaning, then add a fixed tank cleaning line to the monthly maintenance charge so the next three are already paid for.

Who should hold the cleaning report?

The union’s office, with a copy on the notice board or in the residents’ group so everyone can see the date.

Sources

References used in this article, checked in October 2026. This article is general information and not legal advice.

• Geo News, 20 December 2024: University Road main line repaired
• Dawn, 11 June 2025: Five dead after inhaling toxic gases in water tank in Karachi
• Geo News, 13 September 2025: Naegleria claims another life in Karachi, toll hits five in Sindh
• Karachi Water and Sewerage Corporation: What We Do

About Khan Tank Cleaning

This guide is published by Khan Tank Cleaning, a Karachi water tank cleaning company founded in 2005 by Mateen Khan. We work from two branches, DHA Phase 2 and Gulshan-e-Iqbal, and you can read more about the company or contact either branch at any hour. Call or WhatsApp 0333 0293174 (DHA) or 0340 2717530 (Gulshan).

A hospital uses water for almost everything it does: hand washing, cleaning, sterile services, kitchens, laundries, dialysis and patient care. In Karachi that water is stored on site, because the public supply is intermittent, and the people exposed to it include the most vulnerable in the city.

This article is written for administrators, infection control teams and facility managers at hospitals in Karachi, and for clinics, laboratories and care homes. It covers why tank hygiene is a patient safety matter, which organisms are involved, what the regulatory picture looks like, and what a workable plan contains. We are tank cleaning specialists, not clinicians, and nothing here replaces your infection control committee’s judgment.

In brief

• Hospital water is stored on site and reaches patients through taps, showers, equipment and food.
• Legionella and Pseudomonas thrive in warm, stagnant water with sludge and biofilm, and Karachi’s tanks are warm most of the year.
• Healthcare establishments in Sindh are regulated under the Sindh Health Care Commission Act, 2013.
• Clean all tanks at least every three months, one at a time, with records.
• Tank cleaning is one control. Flushing, temperature, disinfection and testing complete the plan.

Why hospital water is a special case

Factor	Why it raises the risk
Patients with weak immune systems	Organisms that healthy people shrug off cause serious infection in newborns, the elderly, transplant, cancer and intensive care patients
Large, complex plumbing	Long pipe runs, dead legs and rarely used outlets hold stagnant water
Aerosols	Showers, taps, humidifiers and respiratory equipment turn water into droplets that are breathed in
Constant demand	A hospital cannot shut down for a day, so tank cleaning gets postponed
Tanker dependence	Supply shortfalls are covered by tankers of unknown origin
High stakes	A waterborne outbreak in a ward is a clinical, legal and reputational crisis

The supply behind every hospital in Karachi

The city receives about 650 million gallons of water a day against demand of more than 1,200, and the network loses a large share of it to leaks. Supply arrives in turns at low pressure, which allows contamination into the pipes. When the Pakistan Council of Research in Water Resources tested Karachi’s water for a Supreme Court commission, 107 of 118 samples were unsafe to drink. The full route is described in our guide to KWSB water supply.

The 2026 supply failures showed how exposed large users are. During the crisis of late April and May whole districts were without water for days, and institutions relied on tankers. Every tanker load and every recharge of the mains brings sediment into storage.

The organisms that matter

Organism	Where it lives	How patients are exposed	Who is most at risk
Legionella	Warm, stagnant water with sludge, scale and biofilm	Inhaling droplets from showers, taps, cooling towers	Older patients, smokers, the immunosuppressed
Pseudomonas aeruginosa	Biofilm in tanks, taps and drains	Contact with wounds, burns, lines and ventilator circuits	Intensive care, burns and neonatal patients
Faecal bacteria such as E. coli and Salmonella Typhi	Sewage-contaminated supply; tank sediment	Drinking, food preparation, hands	Everyone; severe in children and the frail
Naegleria fowleri	Warm, unchlorinated water	Water entering the nose, including ablution	Rare but nearly always fatal
Non-tuberculous mycobacteria	Biofilm in water systems	Aerosols and contaminated equipment	Immunosuppressed and surgical patients

On legionella, the WHO fact sheet states that the bacteria live and grow in water systems at 20 to 50°C, with an optimum of 35°C, that the most common route is inhalation of contaminated aerosols, and that the death rate can reach 40 to 80 percent in untreated immunosuppressed patients. The WHO’s central recommendation is a water safety plan specific to the building, with regular cleaning and disinfection and measures to minimise stagnation.

Karachi’s climate matters here. In much of the world a cold water tank stays below 20°C. Here it does not, for most of the year. The effect of temperature is explained in heat and bacteria in water tanks, and the wider picture of water-related illness in the city in waterborne disease in Karachi.

The regulatory picture

Healthcare establishments in the province fall under the Sindh Health Care Commission Act, 2013, which applies to public and private hospitals, clinics and laboratories. The commission registers and licenses facilities after inspecting them against its standards. Progress has been slow: Dawn reported in July 2025 that between 2018 and 2024 only three public hospitals and 86 private hospitals and clinics had obtained regular licences, out of many thousands that had applied.

Globally the baseline is also low. In 2022 the WHO and UNICEF reported that half of health care facilities worldwide lack basic hygiene services. Accreditation schemes that some Karachi hospitals pursue, such as international hospital accreditation or ISO certification, expect a documented approach to water safety with records. Whatever scheme applies to you, an inspector or surveyor will ask the same thing: show me the schedule and the evidence.

Where the risk concentrates among hospitals in Karachi

• Large public hospitals: very high patient numbers, old buildings, extended plumbing and tight budgets.
• Private hospitals: newer buildings but the same storage, the same supply and the same tankers.
• Small clinics, maternity homes and dialysis centres: often in converted houses with domestic tanks and no one assigned to maintain them.
• Diagnostic laboratories: water quality affects results as well as people.
• Care homes and welfare institutions: frail residents and long stays.

Dental and other clinics in commercial districts are discussed in our area guide to water safety in Defence, Clifton and PECHS.

A water hygiene plan for a health facility

Element	What it involves
Tank inventory	Every underground, rooftop and intermediate tank: size, material, source, areas supplied
Named responsibility	A facility manager for the system; the infection control committee for oversight
Cleaning schedule	All tanks at least every three months, or more often if your committee requires; high-risk areas first
Flushing	Weekly flushing of little-used outlets; removal of dead legs where possible
Temperature and disinfection	Hot water kept hot; a chlorine residual maintained in cold water where your plan calls for it
Testing	Routine microbiological testing by an accredited laboratory, with legionella testing as your risk assessment dictates
After events	Cleaning and flushing after flooding, sewage incidents, long outages, construction or ward reopening
Records	Reports, photographs, invoices, test results and corrective actions in one file

Three months is the interval we recommend for any premises serving the public, and many hospitals choose a shorter cycle for critical areas. The general reasoning is in how often to clean a water tank in Karachi. Tank cleaning is one control among several. It removes the sludge and biofilm in storage. It does not deal with biofilm inside distribution pipework or at outlets, which is why flushing, temperature control and testing belong in the same plan.

Cleaning tanks in a working hospital

1. Survey. Tanks, access, isolation valves and the areas each tank feeds are mapped, and the sequence is agreed with the facility and infection control teams.
2. Continuity. Tanks are cleaned one at a time, at night or at low-demand hours, so that no clinical area loses supply.
3. Safe entry. Ventilation, gas testing, harness and an attendant for every underground or enclosed tank.
4. Cleaning. Jet washing at 3,000+ PSI and vacuum extraction of sludge, removed from site.
5. Disinfection. Agreed in advance with the hospital. We normally use silver-stabilised hydrogen peroxide or food-grade chlorine; if your infection control policy specifies a product or a chlorine residual, we work to it.
6. Rinse, inspection and return to service, with any structural defects photographed.
7. Documentation. A dated report for each tank with photographs, plus a numbered SRB/FBR tax invoice.

The standard sequence is on our cleaning procedure page, and how the disinfectants compare is covered in silver hydrogen peroxide for tank disinfection.

Choosing a contractor

• A documented procedure and a sample report you can review before appointing them
• Confined-space safety practice. Hospital staff should never enter a tank.
• Current quality and safety certificates. See why ISO-certified tank cleaning matters.
• Tax registration and proper invoices. See why SRB and FBR registration matters.
• Willingness to work at night and to your infection control team’s instructions

The household parallel

The reasoning that applies to a hospital applies, on a smaller scale, at home.

In a hospital	In a home
A central tank supplies every ward	An underground or rooftop tank supplies every tap
Patients with weak immunity are most affected	Infants, the elderly and anyone unwell are most affected
A schedule, records and oversight are expected	Nobody checks; it depends on the family
Tankers cover the shortfall	Tankers cover the shortfall

If someone at home is recovering from surgery, undergoing chemotherapy or newly born, treat your own tank with the same seriousness. Our guides to the signs of unsafe water and children’s water safety are a starting point.

Working with us

Healthcare facilities are surveyed free of charge before any quote. Welfare and care institutions named on our clients page include Edhi Homes and Karwan-e-Hayat. Facilities in the south of the city are served by our DHA and Clifton branch and those in the east and centre by our Gulshan and Jauhar branch. For a home tank, the price calculator gives a fixed quote.

Frequently asked questions

How often should hospital water tanks be cleaned?

At least every three months, and more often for critical areas if your infection control committee decides so. Clean immediately after flooding, a sewage incident or a prolonged outage.

Does tank cleaning control legionella?

It removes sludge and biofilm in storage, which is one necessary control. Legionella management also needs flushing, temperature control, disinfection and testing under a water safety plan.

Can tanks be cleaned without interrupting clinical services?

Yes, with planning. Tanks are cleaned one at a time during low-demand hours.

Which disinfectant should a hospital use in its tanks?

That is a decision for your infection control team. We work with silver-stabilised hydrogen peroxide and food-grade chlorine and follow the hospital’s policy.

What documentation will we receive?

A dated service report for each tank with photographs, a recommended next-service date and a tax invoice.

Do small clinics need a water hygiene plan?

A simple one, yes: a list of tanks, a three-month cleaning schedule, treated water for clinical hand washing and instrument rinsing where required, and a file of reports.

Should dialysis and laboratory water be handled differently?

Yes. Those services have their own water treatment systems and standards, managed by clinical engineering. Tank cleaning supports them by improving the feed water but does not replace them.

Sources

References used in this article, checked in October 2026. This article is general information and does not replace clinical or infection control advice.

• Dialogue Earth, 28 July 2017: 91% of Karachi’s water unfit to drink (PCRWR results)
• Dawn, 1 May 2026: Most Karachi areas suffer as water crisis enters second week
• WHO: Legionellosis fact sheet
• Dawn, 27 July 2025: Health facilities registered with the Sindh Healthcare Commission
• WHO and UNICEF, 30 August 2022: Half of health care facilities globally lack basic hygiene services
• UK Health and Safety Executive: Managing legionella in hot and cold water systems

About Khan Tank Cleaning

Khan Tank Cleaning has cleaned residential, commercial and industrial water tanks in Karachi since 2005. The company was founded by Mateen Khan, who still oversees quality control at both branches. More about us, or get in touch: 0333 0293174 for DHA and South Karachi, 0340 2717530 for Gulshan and East Karachi, both answered 24 hours.

A factory’s water tanks sit at the meeting point of three obligations: the law says workers must have wholesome drinking water, auditors and customers want evidence that it is managed, and the tanks themselves are confined spaces that can kill the people sent to clean them. Most sites handle the first two with a signature on a form and the third not at all.

This guide sets out industrial water compliance for an industrial water tank in Karachi in practical terms: what the Sindh Factories Act requires, what audits look for, how cleaning should be done safely, and how to build a simple water management programme for a factory or warehouse.

In brief

• The Sindh Factories Act, 2015 requires a sufficient supply of wholesome drinking water for workers (section 22).
• The same Act restricts entry into tanks and other confined spaces where dangerous fumes are likely (section 48).
• Auditors want an inventory, a schedule, dated reports and water test results.
• Drinking water tanks should be cleaned every three months; fire and process tanks need their own plan.
• Four workers died in a factory water tank in Landhi in 2022. Confined-space control is not optional.

What Sindh law requires

The main statute is the Sindh Factories Act, 2015. Four of its provisions bear directly on water tanks.

Section	Requirement	What it means for tanks
22, Drinking water	Effective arrangements to provide and maintain, at suitable points, a sufficient supply of wholesome drinking water for all workers; points to be marked; cooled water in hot weather where more than 250 workers are employed	The tanks feeding drinking points must deliver wholesome water, and you need to be able to show how you know
15, Cleanliness	Every factory to be kept clean and free from effluvia from drains and other nuisances	Tank surroundings, drainage and sludge disposal
48, Dangerous fumes	No person to enter any chamber, tank, vat, pit or other confined space where dangerous fumes are likely without the safeguards the section specifies: adequate access, a space made safe from fumes, or breathing apparatus with a rope held from outside	Tank cleaning is confined-space work and must be controlled as such
92, Penalties	Fines for contravention of the health and safety provisions, with further daily fines for continuing offences	Non-compliance has a direct cost

This is a summary for orientation, not legal advice. Read the Act, and take advice on how it and other laws, including the Sindh Occupational Safety and Health Act, 2017 and environmental regulations on effluent, apply to your site.

What auditors and customers look for

Beyond the law, most factories are audited by someone: a certification body, a brand’s social compliance auditor, a food safety auditor, an insurer or a multinational customer. The questions about water are much the same whoever asks them.

• Is there a list of all water tanks, with location, capacity and use?
• Is there a cleaning schedule, and has it been followed?
• Are there dated records for each cleaning, from an identifiable contractor?
• Is drinking water tested, and are the results on file?
• How is confined-space entry controlled?
• Is the contractor itself competent, registered and insured against its own risks?

Sector standards add their own requirements. Food and beverage plants running HACCP or ISO 22000 treat water as an ingredient and a hazard to be controlled. Pharmaceutical plants work under GMP rules for water systems. Export-oriented textile units face buyer codes of conduct that include drinking water and worker safety. In each case the auditor wants a documented system, not a verbal assurance.

Why industrial tanks are a different job

	Household tank	Industrial tank
Size	Hundreds to a few thousand gallons	Tens or hundreds of thousands of gallons; often several tanks
Uses	Domestic	Drinking, canteen, process, cooling, boiler feed, fire reserve
Sources	Line and occasional tanker	Line, tanker, borehole, sometimes all three
Sludge	Silt and rust	Larger volumes; may include process residues
Entry risk	Serious	Higher: depth, volume, residual gases, mechanical and electrical hazards
Downtime	A few hours without water	Production, canteen and sanitation all depend on it
Records	A report for the owner	Evidence for law, audit and customers

One point is often missed. Fire reserve tanks and seldom-used process tanks hold stagnant water for months. Stagnant, warm water with sludge and scale is what the UK Health and Safety Executive identifies as favouring legionella, which multiplies between 20 and 45°C. Karachi’s stored water is in that range most of the year.

The Karachi factor

• Unreliable bulk supply. The city receives about 650 million gallons a day against demand above 1,200, and industrial areas rely heavily on tankers and boreholes. See our guide to KWSB water supply.
• Repeated network failures. The Dhabeji outages of 2026 hit Korangi and Landhi among other areas, and each recharge of the mains carries silt into tanks.
• Groundwater quality. Borehole water in industrial zones is typically hard and saline, and may be affected by nearby effluent.
• Heat. Large exposed tanks warm quickly. See heat and bacteria in water tanks.
• Power. Outages stop pumps and leave water standing, as covered in load shedding and water contamination.

Confined-space entry: the part that kills

In January 2022, four workers died in the underground water tank of a textile factory in Landhi. One fell in and was overcome by fumes; three colleagues died trying to rescue him. Police said no safety measures had been taken to cover the tank, and the provincial labour minister ordered an inquiry.

This pattern, in which rescuers become victims, is typical of confined-space deaths. Section 48 of the Factories Act exists to prevent it. In practice, safe entry means:

1. A permit or written authorisation for each entry
2. Isolation of inlets, pumps and electrical equipment
3. Forced ventilation before and during the work
4. Testing the atmosphere before anyone enters, and continuing to monitor it
5. Harness and lifeline, with a tripod or other means of retrieval
6. A trained attendant at the opening for the whole job
7. A rescue plan that does not depend on someone jumping in

If your tank cleaning is done by your own maintenance staff or by a labour contractor with none of the above, you are carrying that risk yourselves.

How often to clean an industrial water tank in Karachi, and how

Tank	Suggested interval	Note
Drinking water and canteen tanks	Every 3 months	Test water after cleaning and at least annually
General service tanks (washrooms, cleaning)	Every 3 to 6 months	Shorter if tanker-fed
Process water tanks	As your quality system or customer standard requires	Disinfectant must be compatible with the process
Fire reserve tanks	Inspect quarterly; clean at least annually	Coordinate with fire safety so cover is maintained
Any tank after flooding, contamination or long shutdown	Before return to service

These are our recommendations, not statutory intervals. The general reasoning is in how often to clean a water tank in Karachi.

The cleaning method scales up from the domestic one: controlled drainage, ventilation and gas testing, jet washing, vacuum extraction of sludge, disinfection, rinse and inspection. Our sequence is on the cleaning procedure page. For industrial jobs the disinfectant is agreed in advance. We normally use silver-stabilised hydrogen peroxide or food-grade chlorine, and if your quality system specifies a particular product we work to that.

A water management programme in six steps

1. Inventory. List every tank: location, capacity, material, source, what it supplies, how it is accessed.
2. Risk-rank. Drinking and food-contact first; stagnant tanks second.
3. Schedule. Fix cleaning dates for the year and put them on the maintenance planner.
4. Appoint an owner. One named person, usually in HSE or administration, holds the file.
5. Record. For every cleaning: date, contractor, report, photographs, invoice, disinfectant used, defects found and when they were fixed.
6. Verify. Laboratory testing of drinking water, and an internal check that the schedule was kept.

Compliance checklist

• Tank inventory is complete and current
• Drinking water points are marked and supplied from cleaned tanks
• Cleaning schedule exists and the last four reports are on file for each tank
• Confined-space procedure is written and followed, including for contractors
• Contractor is SRB and FBR registered and issues tax invoices
• Contractor’s certificates are current and copies are on file
• Water test results are on file
• Tank covers are sound; hatches are secured against falls
• Sludge and wash water are disposed of properly

On the contractor points, see why SRB and FBR registration matters and why ISO-certified tank cleaning matters. How to read a certificate is explained in ISO 9001 and ISO 45001 explained.

Karachi’s industrial zones

• Korangi and Landhi: dense, mixed industry; directly affected by the 2026 supply failures; heavy tanker use.
• SITE and North Karachi: older premises with ageing RCC tanks and pipework.
• Federal B Industrial Area: smaller units in tight plots, often with difficult access.
• Port Qasim and Bin Qasim: large sites, large tanks, long distances from the city’s distribution network.

Korangi, Landhi and the south are covered by our DHA branch; SITE, North Karachi and Federal B Area by our Gulshan branch.

How we work with industrial clients

Industrial sites are always surveyed first, free of charge. The survey covers tank dimensions, sludge depth, access, isolation points, drainage and the client’s own safety rules, and the quote follows in writing. Work is planned around production, typically at night, on a weekly off-day or during a shutdown, and tank by tank so the site is never without water.

Each job produces a dated report with photographs from inside the tank, a recommended next-service date and a numbered SRB/FBR tax invoice. We have cleaned more than 650 industrial tanks, and manufacturing and inspection clients named on our clients page include Mondelez, Shan Foods and SGS. Office staff arranging a cleaning at home can use the online price calculator.

Frequently asked questions

Is there a legal requirement to clean factory water tanks in Sindh?

The Sindh Factories Act, 2015 requires a sufficient supply of wholesome drinking water for workers. It does not set a cleaning interval, but you cannot show the water is wholesome without maintaining the tanks and keeping records.

How often should industrial water tanks be cleaned?

Drinking water tanks every three months, service tanks every three to six months, and process tanks as your quality system requires.

Can our own maintenance team clean the tanks?

Only if they are trained and equipped for confined-space entry and you have a written procedure. Most sites find it safer and simpler to use a specialist contractor.

What records does an auditor expect?

A tank inventory, a schedule, dated service reports with photographs, invoices from a registered contractor, the contractor’s certificates and water test results.

Can cleaning be done without stopping production?

Usually. Tanks are cleaned one at a time, at night or on an off-day, with the sequence agreed at the survey.

Do warehouses fall under the same rules as factories?

It depends on whether the premises meet the Act’s definition of a factory. Whatever the legal position, anyone employing people has a duty to give them safe drinking water, and any tank is a confined space.

Should fire water tanks be cleaned?

Yes, at least annually, with quarterly inspection. Stagnant fire reserve water breeds bacteria and sludge can block pumps and sprinklers. Coordinate the work with whoever is responsible for fire safety so that cover is maintained.

Sources

References used in this article, checked in October 2026. This article is general information and not legal advice.

• The Sindh Factories Act, 2015
• Dawn, 4 January 2022: Four workers die after inhaling toxic fumes in factory’s water tank
• UK Health and Safety Executive: Managing legionella in hot and cold water systems
• Dawn, 1 May 2026: Most Karachi areas suffer as water crisis enters second week
• Karachi Water and Sewerage Corporation: What We Do

About Khan Tank Cleaning

This guide is published by Khan Tank Cleaning, a Karachi water tank cleaning company founded in 2005 by Mateen Khan. We work from two branches, DHA Phase 2 and Gulshan-e-Iqbal, and you can read more about the company or contact either branch at any hour. Call or WhatsApp 0333 0293174 (DHA) or 0340 2717530 (Gulshan).

Lifts, generators and paintwork get a line in every building’s maintenance budget. The water tank usually does not, until tenants start complaining about brown water. For a landlord or property manager in Karachi, the tank is one of the cheapest assets to look after and one of the most expensive to neglect.

This guide is written for anyone acting as a property manager for a water tank in Karachi: owners of rental houses and portions, managers of apartment blocks and commercial plazas, and union office-bearers who have ended up with the job.

In brief

• Whoever controls the tank, usually the landlord, union or manager, should hold the cleaning schedule.
• Shared tanks need cleaning every three months; single houses every four to six.
• Neglect shows up as tenant complaints, damaged plumbing and, in the worst case, liability.
• Write tank cleaning into tenancy agreements and maintenance budgets.
• Never send building staff into an underground tank.

The maintenance item most managers overlook

A tank is out of sight, it has no moving parts, and it gives no warning. Water looks clear while sludge builds on the floor and a bacterial film grows on the walls. By the time tenants notice a smell or colour, the problem is years old. The usual contents of a neglected tank are described in what we find in Karachi’s water tanks.

Why Karachi makes it worse

• Intermittent supply. Water arrives in turns and is stored for days. A World Bank document describes supply ranging from two hours every two days to four hours a day at very low pressure.
• Dirty first flow. Each of the city’s supply crises, such as the Dhabeji failures of 2026, sends silt and rust into underground tanks when the mains are recharged.
• Tankers and boreholes. Sand, salt and scale.
• Heat. Rooftop tanks are warm most of the year. See heat and bacteria in water tanks.
• Sea air. Near the coast, lids, hinges and inspection covers corrode quickly, and a rusted cover is an open tank.

The supply side is explained in our guide to KWSB water supply.

Who is responsible?

There is no single rule in Karachi that names who must clean a tank. In practice responsibility follows control of the tank.

Property	Who normally holds the duty	Common gap
Single house, rented	Whatever the tenancy agreement says; if silent, the landlord for the structure and the tenant for routine upkeep	Agreement says nothing, so nobody does it
Portion in a divided bungalow	The owner, because tanks are shared between portions	Each tenant assumes another will arrange it
Apartment building, handed over	The residents’ union or association, funded from maintenance charges	No budget line; disputed or inactive union
Apartment building, not yet handed over	The builder	Builder has moved on to the next project
Commercial plaza or office building	The building management	Tenants each assume it is in the service charge
Managed portfolio	The property manager, under the management contract	Not listed in the scope of services

For flats in particular, see who is responsible for an apartment building’s water tank. If your situation is disputed, the documents that decide it are the tenancy or sub-lease agreement and the union’s rules, and a lawyer is the right person to read them.

What neglect costs

Tenant complaints and turnover

Water quality is one of the things tenants cannot fix for themselves, which makes it a reliable source of friction. A smell in the bathroom or a brown bucket is a reason to withhold rent, to move out, or to warn the next applicant.

Damage to the building

• Sediment drawn into pipes, where it is far harder to remove than from a tank
• Scale and grit in geysers, float valves, pumps and tenants’ appliances
• Corroded reinforcement where cracks in an RCC tank go unnoticed
• Seepage from a leaking underground tank into foundations or a neighbour’s wall

A cleaning is also the only time anyone looks at the inside of the tank. Cracks, exposed steel and failed joints found early are small repairs.

Liability

If tenants fall ill and the tank turns out not to have been cleaned in years, the question of who was responsible becomes pointed. And if a caretaker or labourer is sent into an underground tank and is overcome by gas, the person who sent him will have to answer for it. In June 2025, five men died in a household water tank in Karachi. Do not let building staff enter a tank.

The property manager’s water tank in Karachi: a maintenance calendar

When	Task
Every month	Check lids, mesh and hatch; look inside each tank with a torch; note any smell or colour
Every 3 months	Professional cleaning of shared tanks in apartment and commercial buildings
Every 4 to 6 months	Professional cleaning for single houses and portions
May or June	Pre-monsoon cleaning; repair lids; raise the underground hatch above floor level
After the rains	Inspect; clean again if floodwater reached the hatch
At every change of tenant	Clean before the new tenant moves in and hand over the report
After a main line failure or long outage	Inspect the underground tank for silt; bring cleaning forward if needed

The reasoning for the intervals is in how often to clean a water tank in Karachi, and the rainy season in our monsoon guide.

Budgeting for it

Tank cleaning is a predictable cost, so treat it like one. For an apartment building, add a line to the annual maintenance budget for four cleanings and divide it across the flats. Spread over twelve months and many households, the amount per flat is small, and it is far easier to collect as part of the regular charge than as a special levy after a complaint. For a portfolio, agree a schedule and a fixed basis of pricing with one contractor so that every property is on the calendar.

What to put in a tenancy agreement

A few sentences prevent most disputes. Have your lawyer adapt them to the property.

• Who arranges cleaning, and how often. For example: the landlord will have both tanks professionally cleaned every six months.
• Who pays. Landlord, tenant, or shared.
• Condition at handover. Tanks cleaned within the previous month, with the service report attached.
• Access. The tenant will allow access on reasonable notice for cleaning and inspection.
• Day-to-day care. The tenant keeps lids closed and reports damage, leaks or changes in the water.
• Safety. Nobody is to enter the underground tank except a professional crew.

A handover checklist for each change of tenant

1. Have both tanks cleaned after the outgoing tenant leaves and before the new one arrives.
2. Walk the new tenant to the tanks. Show them the lids and the motor switch.
3. Hand over a copy of the service report and note the next cleaning date in the agreement.
4. Record the condition of lids, float valves and the hatch in the inventory.
5. Explain the supply days for the area and whether the property uses tankers or a borehole.
6. Make it clear who to call about water, and that nobody is to enter the underground tank.

Ten minutes at handover prevents the most common argument at the end of a tenancy: whose fault the dirty tank is.

Choosing a contractor for a managed property

1. A report for every job, dated, with photographs. This is your evidence to owners and tenants.
2. A proper tax invoice. Managers who pay cash to individuals cannot account for it. See why SRB and FBR registration matters.
3. Safe entry to underground tanks: ventilation, gas check, harness, attendant.
4. Capacity to cover the portfolio across the city, and to work around supply days.
5. A fixed, written price.

The full list is in what to ask before hiring a tank cleaning company.

How we work with property managers

Buildings are surveyed first, free of charge. Cleaning follows our eight-step procedure and is timed for just before the supply turn, when the underground tank is low. Where there are two rooftop tanks they can be cleaned in turn so residents always have one in service. Each tank gets its own dated report with photographs and a recommended next-service date, plus a numbered SRB/FBR tax invoice, which is what owners and unions need for their accounts.

Real estate clients on our clients page include Rufi Builders and Shamir Residency. Properties in the south are handled by our DHA and Clifton branch and those in the east, centre and north by our Gulshan and Jauhar branch. Single houses can get a fixed price online.

The reputational side

Good tenants stay where the basics work. A building that can show a prospective tenant a cleaning report from last month is making a statement about how it is run. It costs very little to be that building.

Frequently asked questions

Who pays for tank cleaning in a rented house in Karachi?

Whoever the tenancy agreement says. Where it is silent, many landlords pay for periodic professional cleaning and tenants handle day-to-day care. Put it in writing at the next renewal.

How often should a rental property’s tank be cleaned?

Every four to six months for a house, every three months for shared building tanks, and at every change of tenant.

Can cleaning be done without cutting water to the whole building?

With planning, yes. Work is timed around the supply turn and rooftop tanks can be cleaned one at a time.

What records should a property manager keep?

For each tank: dates of cleaning, service reports and photographs, invoices, and notes of any defects reported and when they were repaired.

Should the caretaker clean the tank to save money?

No. A small rooftop tank can be rinsed from outside between professional cleanings, but nobody should enter an underground tank without ventilation, a gas check and an attendant.

Can the cost of tank cleaning be recovered from tenants?

If the tenancy agreement or the building’s maintenance rules provide for it, yes. Agree it in advance; trying to recover it after the event causes disputes.

Does a clean tank affect rental value?

It will not raise the rent by itself, but water complaints are a common reason for tenants to leave, and vacancy is the most expensive cost a landlord faces.

Sources

Figures in this article were checked in October 2026 against the following:

• World Bank, 2019: Karachi Water and Sewerage Services Improvement Project, project information document
• Dawn, 1 May 2026: Most Karachi areas suffer as water crisis enters second week
• Dawn, 11 June 2025: Five dead after inhaling toxic gases in water tank in Karachi
• Geo News, 13 September 2025: Naegleria claims another life in Karachi, toll hits five in Sindh

About Khan Tank Cleaning

Khan Tank Cleaning is a Karachi company that does one thing: clean and disinfect water storage tanks. It was started in 2005 by Mateen Khan and now runs branches in DHA Phase 2 and Gulshan-e-Iqbal. Read our background or reach the nearest branch on 0333 0293174 (DHA) or 0340 2717530 (Gulshan), day or night.

In a hotel or restaurant, water from the storage tank reaches the guest in a dozen ways before anyone pours a glass: the salad that was washed in it, the ice in the drink, the plate, the chef’s hands, the shower. A kitchen can be spotless and still serve contaminated food if the tank above it has not been cleaned.

This guide covers hotel water tank cleaning in Karachi and the equivalent for restaurants, cafes, caterers and banquet halls: the risks specific to hospitality, what regulators and corporate clients expect, and a routine that keeps you ahead of both.

In brief

• Tank water reaches guests through washed produce, ice, crockery, hands and showers, not only through the glass.
• Hotels are a known setting for legionella, which grows in warm, stagnant water systems.
• Food businesses in Sindh are licensed and inspected by the Sindh Food Authority.
• Clean every tank every three months and keep the dated report with photographs.
• Flush unoccupied rooms weekly and clean before reopening any closed wing.

Where tank water touches your guests

Use	Why it matters
Washing salad, fruit and herbs	Eaten raw, so nothing kills what the water leaves behind
Ice	Made from tap water and added to drinks untreated
Dish and glass washing	A final rinse in contaminated water recontaminates clean crockery
Hand washing by kitchen staff	The control point for most food-borne illness
Tea, coffee and cooking	Boiling protects; lukewarm dispensers do not
Guest showers and basins	Fine droplets are breathed in; this is how legionella infects
Pools, spas and decorative fountains	Warm, aerated water is the highest-risk setting
Ablution areas and prayer rooms	Water enters the nose

The risks particular to hospitality

Food-borne illness that starts in the tank

The WHO lists diarrhoea, cholera, dysentery and typhoid among the diseases spread by contaminated water, and in a kitchen that water becomes an ingredient. Karachi’s supply is frequently contaminated before it reaches the building, as our guide to KWSB water supply explains. A neglected tank stores that contamination and adds sludge and biofilm of its own. One bad service can affect a whole function.

Legionella in hotel water systems

Hotels are a classic setting for Legionnaires’ disease worldwide. The WHO’s legionellosis fact sheet explains why: the bacteria live and grow in water systems at 20 to 50°C, with an optimum of 35°C, and infect when people inhale contaminated droplets from hot and cold water systems, cooling towers and spas. The death rate is usually 5 to 10 percent. The WHO’s advice centres on a water safety plan for each building: regular cleaning and disinfection, temperature control and minimising stagnation.

Stagnation is the hotel-specific issue. Rooms and whole floors stand empty in the low season, and the water in their pipes does not move. In Karachi’s climate, a cold water tank is rarely cold; it sits in the growth range for most of the year. See heat and bacteria in water tanks.

Tankers and boreholes

Few Karachi hotels can run on piped supply alone. Tanker and borehole water add sand, salts and unknown microbial loads, and they change from one delivery to the next.

What the standards actually are

Hospitality businesses answer to more than one authority, and to their customers.

• Sindh Food Authority. Food businesses in the province are licensed and inspected under the SFA Act, 2016. The authority reported 47,875 inspections and improvement notices, and 370 food outlets sealed, between July 2025 and January 2026. Inspectors look at hygiene across the premises, and water is part of that.
• Potable water. The basic requirement in every food hygiene code is that water used for food preparation, ice and washing is of drinking quality. Under the WHO guidelines, that means no detectable E. coli in any 100 ml sample.
• Food safety systems. Kitchens operating HACCP or ISO 22000 are expected to control water as a hazard, with records to show it.
• International brands and corporate clients. Chain hotels have brand standards; companies booking events or contracts often audit their suppliers.
• Workplace law. Your staff are entitled to safe drinking water too.

We are a tank cleaning company, not a regulator, so check the current licence conditions with the Sindh Food Authority. What inspectors and auditors generally want to see is simple: the date of the last cleaning and the paperwork to prove it.

A tank hygiene routine for hotels and restaurants

Frequency	Task	Record to keep
Daily	Look at and smell the water at the kitchen tap first thing; check ice machine hygiene	Opening checklist
Weekly	Flush taps and showers in unoccupied rooms and closed areas for several minutes	Flushing log
Monthly	Inspect tank lids, mesh and hatches; look inside each tank with a torch	Inspection sheet
Every 3 months	Professional cleaning and disinfection of all tanks	Service report, photographs, invoice
Every 6 to 12 months	Laboratory test of water at the kitchen tap and a guest room	Lab report
Before reopening a wing or after refurbishment	Clean tanks serving it and flush all outlets	Service report
After flooding, a sewage incident or a long supply crisis	Immediate cleaning	Service report

Every three months is our recommendation for premises serving the public; busy kitchens and large hotels sometimes choose a shorter cycle. The general schedule is in how often to clean a water tank in Karachi.

Warning signs in a commercial kitchen or hotel

• Cloudy ice, or ice with a taste
• A musty smell from showers or from the first water out of a tap
• Brown water after the pumps start
• Dishwasher and ice machine filters blocking quickly
• Scale building up fast on kettles, boilers and shower heads
• Guest complaints about the water, or several staff off with stomach upsets in the same week

More signs are listed in ten signs your water may be making you sick.

Banquet halls, caterers and cloud kitchens

These businesses have a pattern of their own. A banquet hall may stand idle for days and then serve a thousand guests in one evening, so its tanks alternate between stagnation and very heavy draw, which is when settled sludge is pulled into the system. Caterers prepare food in one place and serve it in another, often using the venue’s water for washing and ice without knowing anything about the venue’s tank. Delivery-only kitchens operate from small rented units where the tank belongs to a landlord the operator has never met.

The practical rules: clean before the wedding season and again midway through it, run all taps for several minutes before a large event, bring your own treated water for ice and salad washing when catering off site, and if you rent, find out who maintains the tank before you sign.

Hotel water tank cleaning in Karachi: how the work is done

Hospitality sites are surveyed first, free of charge, because tank numbers, access routes and service hours differ everywhere. The cleaning follows our eight-step procedure:

1. Survey and written quote
2. Controlled drainage to a drain, with the supply outlet protected
3. Ventilation and gas check before anyone enters an underground or sealed tank
4. Jet washing of walls, floor and ceiling at 3,000+ PSI, with reduced pressure on fibreglass and plastic
5. Vacuum extraction of sludge, removed from the premises
6. Disinfection with silver-stabilised hydrogen peroxide, or food-grade chlorine for heavily contaminated tanks
7. Rinse until clear, and inspection of walls, joints and covers
8. Dated report with photographs, next-service date and a numbered tax invoice

Work can be scheduled overnight or on a closed day. Where a property has more than one tank, they can be cleaned one at a time so that kitchens and rooms stay supplied. The disinfectant leaves no taste after rinsing, which matters in a kitchen; the detail is in silver hydrogen peroxide for tank disinfection.

The paperwork an inspector or auditor wants

• A list of every tank: location, size, material, what it supplies
• The cleaning schedule and the last three service reports for each tank
• Photographs from inside the tanks
• Tax invoices from a registered contractor. See why SRB and FBR registration matters.
• The contractor’s current certificates. See why ISO-certified tank cleaning matters.
• Laboratory results and the flushing log

Keep it in one file. A business that can hand that file over in a minute rarely has a difficult inspection.

Who we work with

Hospitality clients named on our clients page include Avari Towers, World-Inn Hotel and Qasr-e-Shereen, alongside food manufacturers such as Mondelez and Shan Foods. Restaurants and hotels in the south of the city are served by our DHA and Clifton branch, and those in the east and centre by our Gulshan and Jauhar branch. The wider picture for commercial premises in Defence, Clifton and PECHS is in this area guide. For your own home, the price calculator gives an instant quote.

Frequently asked questions

How often should a restaurant clean its water tank?

Every three months, and immediately after flooding, a sewage problem or a prolonged supply outage.

Do we have to close during the cleaning?

No. The work can be done overnight or on a closed day, and multiple tanks can be cleaned in turn.

Is the disinfectant safe for a kitchen water supply?

Yes. It is rinsed out before the tank is refilled. Silver-stabilised hydrogen peroxide breaks down to water and oxygen and leaves no taste.

We use a filtration plant. Do we still need tank cleaning?

Yes. A plant treats water at one point. Tanks before and after it still collect sludge and biofilm, and a dirty tank shortens the life of filters and membranes.

Will the report satisfy the Sindh Food Authority?

The report shows the date, the work done and photographs. Whether it meets a particular licence condition is for the authority to say, so check current requirements with them.

Is ice a real risk?

Yes. Freezing does not kill most bacteria, and ice is added to drinks without any further treatment. Make ice only from treated water and clean the machine regularly.

How should a hotel handle a long-vacant floor?

Flush every tap and shower weekly while it is closed, and before reopening clean the tanks that serve it and run all outlets thoroughly.

Sources

Figures in this article were checked in October 2026 against the following:

• WHO: Drinking-water fact sheet
• WHO: Legionellosis fact sheet
• APP, 23 February 2026: Sindh Food Authority board meeting and inspection figures
• WHO: Guidelines for Drinking-water Quality

About Khan Tank Cleaning

Khan Tank Cleaning has cleaned residential, commercial and industrial water tanks in Karachi since 2005. The company was founded by Mateen Khan, who still oversees quality control at both branches. More about us, or get in touch: 0333 0293174 for DHA and South Karachi, 0340 2717530 for Gulshan and East Karachi, both answered 24 hours.

A child spends six or seven hours a day at school and drinks from whatever the school provides. In Karachi that water has almost always been stored in a tank on the premises, sometimes for days. Parents choose schools on fees, results and distance. Very few ask when the water tank was last cleaned, and very few schools could answer.

This article is about school water safety in Karachi: why the issue goes unenforced, what the risks are, what parents can reasonably ask, and what a workable water hygiene routine looks like for a school, college or university.

In brief

• School water in Karachi is stored in tanks on the premises, and no rule we know of sets how often they must be cleaned.
• Hundreds of children share one tank, and it stands unused through weekends and long holidays.
• Coolers chill water. They do not make it safe.
• Parents can ask seven simple questions. Schools should be able to answer them.
• A cleaning before each term gives a natural three-month cycle.

A problem hidden in plain sight

The scale of the wider problem is on record. In January 2026 Sindh’s education minister told the provincial assembly that 14,000 schools in Sindh have no drinking water facility at all. Globally, the WHO and UNICEF’s monitoring programme reports that 77 percent of schools had a basic drinking water service in 2023, leaving 447 million children without one.

Karachi’s private and better-resourced schools mostly do have water. The question there is not whether it exists but what condition it is in. A school with a cooler in every corridor can still be serving water from an underground tank that has not been opened in three years.

Why nobody enforces it

• No specific rule. We are not aware of any regulation in Sindh that sets a cleaning interval for school water tanks or requires schools to publish one.
• Inspections look elsewhere. Registration and inspection of schools tend to concentrate on premises, staffing and curriculum.
• Split responsibility. In rented buildings the school assumes the landlord maintains the tank, and the landlord assumes the school does.
• Out of sight. The principal sees classrooms every day and the tank never.
• Parents do not ask. What is not asked about is not prioritised.

The absence of a rule does not remove the duty. A school has charge of other people’s children, and providing safe drinking water is part of that.

Why schools are more exposed than homes

Factor	At home	At school
People using one tank	A family	Hundreds or thousands
Who is drinking	All ages	Mostly children, who are most vulnerable to waterborne illness
Usage pattern	Steady, every day	Heavy in term; stagnant through weekends and long holidays
Treatment at the tap	Often a filter or boiled water	Coolers with filters that may not be serviced
Who notices a problem	The family, quickly	Nobody connects scattered absences across classes
Building	Purpose-built	Often a converted bungalow with a tank sized for one household

The holiday problem

Water that sits unused goes stale. Over a two-month summer break a school’s tanks and pipes hold the same water through the hottest weeks of the year. The WHO notes that legionella bacteria live and grow in water systems at 20 to 50°C, with stagnation as a key risk, and Karachi’s tanks are in that range all summer. The first week of term is when that water reaches the children. Heat is covered in more detail in heat and bacteria in water tanks.

The cooler problem

Electric coolers chill water; they do not purify it. Many have a small filter cartridge that is rarely changed, and the reservoir inside the cooler is itself a tank that needs cleaning. A cold drink from a dirty cooler fed by a dirty tank is still dirty water.

The health picture

UNICEF attributes 53,000 deaths of children under five in Pakistan each year to diarrhoea linked to poor water and sanitation. School-age children are sturdier, but stomach infections, typhoid and hepatitis A and E still mean missed lessons and, in a classroom, quick spread from one child to the next. Karachi was the centre of the drug-resistant typhoid outbreak recorded by WHO from 2016. The infections and their routes are explained in waterborne disease in Karachi, and our guide for parents covers what families can do at home.

Ablution areas deserve a mention. Naegleria fowleri infects through water entering the nose, and the Sindh health department’s advice after the deaths of 2025 was to clean tanks before summer and keep water chlorinated.

What parents can ask

These are fair questions for an admissions meeting or a parent-teacher association, and a well-run school will have answers.

1. Where does the school’s water come from: the line, tankers or a borehole?
2. How many tanks are there, and when was each last cleaned?
3. Is there a written report from the cleaning, with photographs?
4. How is drinking water treated, and when were the cooler filters last changed?
5. Who on the staff is responsible for water?
6. What happens to the tanks before school reopens after the summer?
7. Has the water ever been laboratory tested?

Ask as a group if you can. One parent’s question is an awkward moment; a PTA’s request becomes an agenda item. Meanwhile, send your child with a filled bottle from home, and keep your own tank in order.

School water safety in Karachi: a plan for administrators

When	Action
Two weeks before each term	Clean and disinfect all tanks; clean cooler reservoirs; replace filter cartridges
First day back after any long break	Run every tap and cooler for several minutes before pupils arrive
Every month	Check lids, mesh and the area around the underground hatch; look inside each tank with a torch
Every three months	Professional cleaning of all tanks
After flooding, a sewage leak or a long supply crisis	Immediate cleaning
Once a year	Laboratory test of drinking water from an accredited lab
Always	One named member of staff holds the water file: reports, invoices, test results, filter change dates

Three terms and a pre-summer cleaning give a natural quarterly rhythm, which matches the interval we recommend for any premises serving the public. The reasoning is in how often to clean a water tank in Karachi.

Larger campuses

Universities and colleges have more to manage: hostels, cafeterias, laboratories, several buildings with separate tanks, and sometimes their own boreholes. Start with an inventory of every tank, its size, material, location and source, and clean them on a rotating schedule so that no building is ever without water. Hostels and canteens should be treated like residential and food premises respectively; see our guides for apartment buildings and hotels and restaurants.

Rented premises

If the school rents its building, settle in writing who cleans the tanks and who pays. The school should hold the schedule whatever the lease says, because it is the school’s pupils who drink the water.

Nurseries, tuition centres and madrasas

The same reasoning applies to smaller settings, which are often less well equipped than schools. A nursery or day-care centre in a converted house relies on a domestic tank while looking after the age group most at risk. Tuition and coaching centres run in the evenings in rented floors where nobody knows who maintains the tank. Madrasas and hostels combine drinking, cooking, bathing and ablution for residents who live on site.

If you run one of these, the minimum is the same: know where your water comes from, clean the tanks every three months, treat drinking water, and keep the report. If your child attends one, the questions above apply just as well.

Choosing a contractor for a school

• Safety first. Work must be done when children are not on site, and underground tanks entered only with ventilation, a gas check and an attendant. Never allow school staff to go into a tank.
• A disinfectant suitable for drinking water tanks, rinsed out before refilling.
• A dated report with photographs for the school’s records.
• A proper tax invoice for the accounts. See why SRB and FBR registration matters.
• Holiday and weekend working.

A general checklist is in what to ask before hiring a tank cleaning company.

How we work with schools and universities

Educational institutions are surveyed first, free of charge, so that tank count, access and timing are agreed in advance. Cleaning follows our eight-step procedure: drainage, ventilation and gas check, jet washing at 3,000+ PSI, vacuum extraction, disinfection, rinse and inspection, and a dated report with photographs. Both branches work around the clock, including Sundays and public holidays, so the work can be done while the campus is empty.

Institutions on our clients page include IBA and SZABIST. Campuses in the south of the city are served by our DHA and Clifton branch and those in the east and centre by our Gulshan and Jauhar branch. Parents arranging a cleaning at home can get a price online.

Frequently asked questions

How often should a school clean its water tanks?

Every three months, with a cleaning shortly before each term and always before reopening after the summer break.

Is there a law requiring schools in Karachi to clean their tanks?

We are not aware of a rule that sets a specific interval. Schools nonetheless have a duty of care for the children in their charge, and safe drinking water is part of it.

Are water coolers enough?

No. A cooler chills water and may filter it lightly. It does not make contaminated water safe, and its own reservoir and filter need regular attention.

Can tanks be cleaned during term?

Yes, at weekends or overnight. Rooftop tanks take two to four hours and underground RCC tanks four to eight.

What should a school keep on file?

For each tank: the date of every cleaning, the service report and photographs, the invoice, filter change dates and any laboratory results.

Should schools provide filtered water or ask children to bring their own?

Both. A bottle from home covers the child; safe water at school covers the refill and the children who forget. The filter on a school cooler still needs a clean tank behind it.

How can a PTA raise this without causing offence?

Frame it as a request for information: the cleaning dates and the last report. Most administrators respond well to a specific, reasonable question, and the request itself often prompts a cleaning.

Sources

Figures in this article were checked in October 2026 against the following:

• The Express Tribune, January 2026: 14,000 schools without water in Sindh
• WHO/UNICEF Joint Monitoring Programme: WASH in schools, 2024 highlights
• WHO: Legionellosis fact sheet
• UNICEF Pakistan: Water, sanitation and hygiene
• WHO Disease Outbreak News, 27 December 2018: Typhoid fever, Pakistan
• Geo News, 13 September 2025: Naegleria claims another life in Karachi, toll hits five in Sindh

About Khan Tank Cleaning

This guide is published by Khan Tank Cleaning, a Karachi water tank cleaning company founded in 2005 by Mateen Khan. We work from two branches, DHA Phase 2 and Gulshan-e-Iqbal, and you can read more about the company or contact either branch at any hour. Call or WhatsApp 0333 0293174 (DHA) or 0340 2717530 (Gulshan).