Water Management in Apartment Buildings: Pumps, Tanks and Fair Sharing

Ask any tenant in Dhaka what makes a flat pleasant to live in and water will be near the top of the list. No water in the morning, muddy water after a pipe repair, or a tenant upstairs who never gets pressure can sour relationships faster than a rent increase. Water management in apartment buildings covers the supply connection, the underground reservoir, pumps, rooftop tanks, pipes, cleaning and, just as importantly, how the water bill is shared fairly among flats.

This guide is for landlords, building owners and flat owners' associations in Bangladesh. It explains how a typical building water system works, the routines that keep it reliable, how to divide the bill in a way tenants accept, and how to handle shortages and complaints. The numbers used are illustrative only.

How a Typical Building Water System Works

Most multi-storey buildings in Dhaka, Chattogram and other cities follow a similar design:

1. Supply connection: from the city's water supply authority (for example Dhaka WASA or Chattogram WASA), or from a private deep tubewell where permitted, or both.
2. Underground reservoir: water from the line is stored in a ground-level or underground tank, because mains pressure is rarely enough to reach upper floors.
3. Pump: an electric pump lifts water from the reservoir to the rooftop (overhead) tank.
4. Overhead tank: water flows by gravity from the roof to each flat.
5. Distribution pipes: risers and branch lines to kitchens and bathrooms, sometimes with separate valves per flat.

Each link in this chain can fail: supply cuts, a leaking reservoir, a burnt pump motor, an overflowing or empty roof tank, or a blocked pipe. Good management means knowing each part and checking it regularly.

Know Your Water Sources and Connections

Keep a simple file for the building's water connections: the WASA account or customer number, connection size, meter location, the name on the account, and copies of recent bills. If the building has a deep tubewell, keep records of its approval and maintenance. Rules on private tubewells, connection sizes and tariffs are set by the relevant WASA and authorities and change over time, so check directly with them before making changes.

If the connection is still in the name of a previous owner or the developer, arrange for the name to be updated through the proper process. Unclear ownership of the connection causes trouble when there is a billing dispute or a need to upgrade.

Pumps: The Heart of the System

Choosing and sizing

The pump must be powerful enough to fill the overhead tank in a reasonable time given the building's height and daily demand. An undersized pump runs for hours, overheats and fails often. An oversized one wastes electricity and can damage pipes. Take advice from a qualified plumber or engineer when replacing a pump.

Always have a backup

A single pump means no water the day it fails. Many buildings install two pumps, used alternately, so one can run while the other is repaired. Alternate them weekly so both stay in working order.

Automatic controls

Float switches or automatic level controllers turn the pump on when the overhead tank is low and off when it is full. They prevent overflow on the roof and dry-running of the pump when the reservoir is empty. They are cheap compared with a burnt motor, but they need periodic checks.

Pump operation schedule

Where the caretaker runs the pump manually, set fixed times (for example early morning and evening) and post them. During load shedding, coordinate with the generator schedule so the tank is filled when power is available. For how caretaker duties like this fit into a wider staff plan, see our guide on managing caretakers, guards and cleaners.

Tanks: Cleaning and Hygiene

Dirty tanks are a health risk. Sediment, algae and even dead insects or birds can collect in reservoirs and roof tanks. A reasonable routine:

These frequencies are practical suggestions, not official requirements. Give tenants notice before tank cleaning, since supply will be off for several hours, and ask them to store some water in advance.

Sample notice: "Dear residents, the rooftop and underground water tanks will be cleaned on Saturday from 9 am to 3 pm. Water supply will be off during this time. Please store water on Friday night. The water may look slightly cloudy for a short time after supply resumes. Thank you for your cooperation."

After waterlogging or flooding, check whether dirty water has entered the underground reservoir; this is a common problem in low-lying areas during the monsoon. Our guide on monsoon waterlogging and rental property has more on protecting the building in the rainy season.

Sharing the Water Bill Fairly

In most buildings there is one WASA meter for the whole building, not one per flat. The bill, plus the electricity used by the pump, must be shared. There are several common methods:

Whatever method you choose, write it in the rental agreement and apply it consistently. Most disputes arise when the method is unclear or changes without notice. For how water fits alongside electricity and gas in a tenant's monthly costs, see utility bills in a rented flat.

Worked Example: Dividing the Water and Pump Costs

For example (illustrative): a building has 6 flats. This month's WASA bill is Tk 5,400, and the pump's electricity (estimated from its common meter) is Tk 1,800. Total water cost: Tk 5,400 + Tk 1,800 = Tk 7,200.

Method A, equal share: Tk 7,200 / 6 flats = Tk 1,200 per flat.

Method B, by occupants: the flats have 2, 3, 4, 4, 5 and 6 residents, a total of 24. Cost per person = Tk 7,200 / 24 = Tk 300. So the flat with 2 residents pays 2 x Tk 300 = Tk 600; the flat with 6 residents pays 6 x Tk 300 = Tk 1,800; the flats with 4 residents pay Tk 1,200 each.

Check: Tk 600 + Tk 900 + Tk 1,200 + Tk 1,200 + Tk 1,500 + Tk 1,800 = Tk 7,200. The totals match.

Method B feels fairer to small households, but it requires updating the occupant count when families change. Many landlords use equal shares for simplicity and then agree adjustments for unusual cases, such as a flat used as an office with few people during the day.

Handling Water Shortages

Shortages happen because of supply cuts, low pressure in the area, pump failure, load shedding or high summer demand. A calm, organised response reduces tension:

• Inform tenants quickly: what happened, what you are doing, and when you expect normal supply.
• Ration fairly: if water is limited, supply at fixed times so upper floors are not always last.
• Arrange alternatives: in prolonged supply cuts, many buildings buy water from WASA's water supply services or authorised suppliers; share the cost by the agreed method.
• Check for leaks: a running toilet cistern or a burst pipe can empty an overhead tank overnight.
• Encourage saving: a friendly notice asking tenants to fix dripping taps and avoid washing cars with hose pipes during shortages.

Leaks, Seepage and Pipe Problems

Hidden leaks waste water, raise bills and cause seepage in walls and ceilings, which leads to damp, mould and disputes between flats. Signs of a leak include the overhead tank emptying faster than usual, damp patches on walls or ceilings, and a water meter that moves when all taps are off. Fix leaks promptly with a qualified plumber, and record the cause, cost and flat affected in your maintenance log.

In older buildings, galvanised iron pipes may be rusting inside and restricting flow. Replacing risers is a significant job, best planned for a dry season and discussed with tenants in advance.

Water Quality and Safety

Tenants increasingly boil or filter drinking water, but the building's water should still be as clean as possible. Keep tanks covered and locked, clean them on schedule, repair broken lids, and avoid cross-connections between drainage and supply lines. If tenants complain of smell, colour or illness, stop and investigate immediately and consider a laboratory test. Arsenic and iron can be concerns with some groundwater sources; a test will tell you whether treatment is needed.

Water Saving Measures That Pay Off

• Fix dripping taps and running cisterns quickly.
• Install float controls to stop roof tank overflow.
• Use dual-flush cisterns and aerator taps when replacing fittings.
• Consider rainwater harvesting on the roof for cleaning and gardening, where the structure and rules allow.
• Schedule pump operation to avoid running it when the tank is already full.

For example (illustrative): if a leaking cistern wastes 200 litres per day, that is 200 x 30 = 6,000 litres per month. Fixing a Tk 500 flush valve can remove that waste and reduce pump running time too.

Budgeting for Pumps, Tanks and Repairs

Water systems need money set aside, not just emergency spending. A simple annual budget avoids the situation where a pump burns out in April and nobody knows who pays. List the predictable items and divide them by twelve to get a monthly provision.

For example (illustrative): a 6-flat building plans for two tank cleanings of both tanks at Tk 4,000 per cleaning (2 x Tk 4,000 = Tk 8,000), one water test at Tk 3,000, routine plumbing repairs of about Tk 9,000 a year, and a pump rewinding or replacement fund of Tk 12,000 a year. Total: Tk 8,000 + Tk 3,000 + Tk 9,000 + Tk 12,000 = Tk 32,000 per year. Monthly provision: Tk 32,000 / 12 = about Tk 2,667, or about Tk 445 per flat if shared equally across 6 flats.

In a rented building owned by one landlord, this provision usually comes out of rent or a service charge. In a building where flats are owned by different people, the owners' association typically collects it as part of the monthly service charge and reports spending at its annual meeting. Either way, keep receipts for every payment so the numbers can be shown to tenants or owners if questioned.

Decisions in owner-occupied buildings

Where flats are individually owned, decisions such as installing a second pump, replacing risers or adding sub-meters should be taken at an owners' meeting and recorded in writing. Landlords who let their flat in such a building should tell their tenant how the association handles water, and pass on notices promptly.

Common Mistakes in Water Management

• Only one pump, with no backup when it fails.
• No tank cleaning schedule, until tenants complain about dirty water.
• Unclear bill sharing not written in the agreement.
• Ignoring small leaks that later cause seepage disputes.
• Leaving tank lids open or unlocked on the roof.
• Not informing tenants before shutdowns.
• Changing the sharing method suddenly without discussion.

Water Management Checklist

1. WASA account details and connection records filed.
2. Two pumps, alternated weekly, with automatic level controls.
3. Tank cleaning scheduled and recorded.
4. Annual water quality test.
5. Written bill-sharing method in every agreement.
6. Monthly calculation shared with tenants, with the WASA bill copy.
7. Leak checks as part of routine maintenance.
8. Shortage plan and notice template ready.

For more on running a whole building, see our apartment building management guide.

Final Thoughts

Good water management in apartment buildings is mostly routine: reliable pumps with a backup, clean and covered tanks, quick leak repairs, clear communication and a fair, written method for sharing costs. Get those right, and water stops being a monthly argument.

Sharing water costs is easier when the numbers are transparent. In Bariwala ERP (বাড়িওয়ালা ERP) you can record water and pump costs as building expenses, include agreed shares on each flat's monthly invoice, and handle pump or leak complaints through maintenance requests, so tenants see exactly what they are paying for.