Gulshan-e-Iqbal and Gulistan-e-Johar are among the most densely built parts of Karachi: block after block of apartment buildings, each with an underground tank, a motor and a tank on the roof, shared by everyone inside. When the water is bad here, it is bad for a whole building at once.
This article looks at the state of the average water tank in Gulshan, Karachi and in neighbouring Johar: how the area is supplied, what has gone wrong recently, why shared tanks are a particular problem, and what residents and unions can do.
In brief
- Most residents here share an underground tank and rooftop tanks with the whole building.
- The 84-inch University Road main failed in late 2024, and the dirty first flow afterwards settled in tanks across the area.
- Suction pumps, borehole water and inactive unions make the problem worse.
- Shared tanks should be cleaned every three months, and the union is normally responsible.
- A written proposal with a date and a quote gets a tank cleaned faster than a complaint does.
How the area gets its water
Piped water comes from the Karachi Water and Sewerage Corporation (KWSC) through large mains that run along University Road and into the blocks. Like the rest of the city, the area receives water in turns, not continuously. Karachi as a whole gets about 650 million gallons a day against a need of more than 1,200, a gap explained in our guide to KWSB water supply. Residents fill the gaps with tankers and with borehole water, which in much of the area is hard and salty.
The University Road failure of 2024
On 29 November 2024 the 84-inch main on University Road burst during construction of the BRT Red Line. Three consecutive leakages followed, and Geo News reported a shortage of 150 million gallons a day before the line was fully repaired about three weeks later. Gulistan-e-Jauhar, Mosamiyat, Safoora and several blocks of Gulshan-e-Iqbal were among the areas left dry, along with Bahadurabad, Tariq Road, Garden, Lyari and Saddar.
Two things happened to tanks during those weeks. First, households and buildings bought tanker water from wherever they could get it. Second, when the main was recharged, the first water through carried rust, silt and whatever had entered the empty line. All of that settled in underground tanks across the area, and unless a tank has been properly cleaned since, it is still there.
Every later repair or diversion of a main produces a smaller version of the same event.
Why Gulshan and Johar tanks are especially exposed
- Shared tanks. One underground tank and one or two rooftop tanks serve 20, 40 or more flats. A single contaminated fill reaches every family.
- High turnover. Large buildings pump several times a day, so sludge is constantly stirred.
- Suction pumps. Where pressure is weak, buildings pull water from the main with powerful motors. That lowers pressure in the street and draws contamination in through leaks.
- Old lines under busy roads. Traffic and repeated excavation damage pipes, and water and sewer lines run close together.
- Borehole water. Mixed into the same tanks, it leaves heavy scale.
- Nobody in charge. In many buildings the union is informal or disputed, and tank cleaning is the first thing to slip.
What builds up in a shared water tank in Gulshan, Karachi
| Deposit | Where it comes from | What residents notice |
|---|---|---|
| Sludge on the floor | Silt and rust from the mains, sand from tankers | Brown water when the tank runs low; grit in buckets |
| Biofilm on walls | Bacteria attaching to any wet surface | Slippery tank walls; musty smell |
| Algae | Light entering through broken or missing covers | Green tint; earthy taste |
| Mineral scale | Borehole water | White crust on taps and geysers; blocked float valves |
| Insects and debris | Open hatches on roofs used for drying clothes and storage | Larvae and floating matter |
These match what our crews find across the city, described in what we find in Karachi’s water tanks.
Houses, flats and Scheme 33
The area is not all apartment blocks, and the right approach differs with the property.
- Older blocks of Gulshan-e-Iqbal: a mix of bungalows and low-rise flats. Many bungalows have been divided into portions that share the original tanks, so three households depend on a system built for one.
- Gulistan-e-Johar: mostly multi-storey apartment projects with large shared tanks, pumped several times a day.
- Scheme 33 and Gulzar-e-Hijri: newer societies with heavier reliance on tankers and boreholes, so more sand and scale.
- Commercial strips along the main roads: restaurants, clinics and schools in converted buildings, which should be on a three-month cycle whatever the residents upstairs decide.
Symptoms residents tend to ignore
- Stomach upsets that go round the building
- Water that is brown for the first minute after the motor runs
- A musty or earthy smell in the bathroom
- Filters that clog within weeks
- Skin or eye irritation after bathing
None of these proves the tank is at fault, but several together in one building is a strong hint. The full list is in ten signs your water may be making you sick, and the infections involved are covered in waterborne disease in Karachi. Families with young children should also read our guide for parents.
Who is responsible in an apartment building?
The tanks are common property, so the duty sits with whoever manages the common areas: the residents’ union or association, the builder if the project has not been handed over, or the landlord in a building under single ownership. Individual flat owners cannot clean a shared tank on their own, but they can and should ask for it.
We set out the roles, and how to raise the issue, in who is responsible for an apartment building’s water tank. Managers of several buildings will find a planning approach in our guide for property managers.
What flat residents can do this week
- Ask the union for the date of the last cleaning and whether there is a report with photographs.
- Look at the roof. Are the tank covers in place and intact? Is the area around them clean?
- Raise it in writing in the building’s group, with a proposed date and a quote, so it becomes a decision and not a complaint.
- Share the cost. Split across the flats, a proper cleaning every three months is a small monthly amount per household.
- Boil or filter drinking water regardless. A filter does not replace a clean tank, as we explain in water filter versus tank cleaning.
- If your flat has its own small tank or drum, clean and cover that too.
How often should tanks here be cleaned?
| Property | Recommended interval |
|---|---|
| Apartment building, shared tanks | Every 3 months |
| Independent house, mostly piped supply | Every 4 to 6 months |
| House or building using borehole or tanker water | Every 3 months |
| Shops, clinics, schools and restaurants | Every 3 months |
| After a main line failure, flooding or sewage leak | Straight away |
The reasoning is in how often to clean a water tank in Karachi. The Sindh health department’s minimum for every tank is once a year before summer.
Cleaning a shared tank without leaving the building dry
Unions often put the job off because they fear a day without water. It can be planned around that. We survey the building first, free of charge, agree a day just before the supply turn when the underground tank is low, and where there are two rooftop tanks they can be cleaned one at a time so the building always has one in service. Residents are asked to store a few buckets for the hours the underground tank is out of use, typically four to eight.
The method is our standard eight-step procedure: drainage, ventilation and a gas check before anyone enters, jet washing at 3,000+ PSI, vacuum extraction of the sludge, disinfection, rinse and inspection. The union receives a dated report with photographs and a numbered SRB/FBR tax invoice for its accounts.
Our Gulshan-e-Iqbal branch
Our branch at Suite-203, Mumtaz Manzil, Block 16, Gulshan-e-Iqbal handles water tank cleaning across Gulshan-e-Iqbal, Gulistan-e-Johar and East Karachi, including Scheme 33, Federal B Area, Nazimabad, North Nazimabad and PECHS. The number is 0340 2717530, answered 24 hours. Houses can get a fixed price online; buildings are quoted after the survey. The south of the city is served by our DHA and Clifton branch.
Frequently asked questions
How often should an apartment building’s tank be cleaned?
Every three months for shared tanks, and immediately after a main line failure or any sign of sewage contamination.
Can I get the building’s tank cleaned if the union will not act?
Not on your own, because it is common property. Put the request in writing with a quote attached, gather support from other residents, and offer to coordinate the day.
Why is our water brown after the motor runs?
The pump is stirring sludge on the tank floor, or the level has dropped close to it. It is one of the clearest signs that cleaning is overdue.
Is borehole water safe to store in the same tank?
It is usually hard and salty and can carry contamination in dense areas. It also leaves heavy scale. If you rely on it, clean the tank every three months and treat drinking water.
How long will the building be without water?
With planning, a few hours for each tank. Rooftop tanks take two to four hours and underground RCC tanks four to eight.
Do you clean tanks in Scheme 33 and Gulshan-e-Maymar?
Yes. Both are covered from the Gulshan-e-Iqbal branch.
Our building uses a suction pump on the line. Should we stop?
Where the line pressure is enough to fill the underground tank unaided, yes. Suction lowers pressure in the street main and can draw contaminated groundwater in through leaks. Where there is no alternative, clean the tank more often.
Sources
Figures in this article were checked in October 2026 against the following:
- Geo News, 20 December 2024: University Road main line repaired
- Karachi Water and Sewerage Corporation: What We Do
- Dawn, 1 May 2026: Most Karachi areas suffer as water crisis enters second week
- 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.
Mateen Khan is the Founder & Owner of Khan Tank Cleaning, Karachi’s first dedicated professional water tank cleaning company (est. 2005). With 20+ years of industry experience, he leads an ISO 9001 & ISO 45001 certified team that follows a strict 8-step process using industrial equipment and food-grade disinfectants. Mateen is committed to making clean, safe water accessible to every household and business in Karachi.