The hidden crisis of residential water quality in Greater Taipei: pollution from rooftop water towers
In many apartments and community buildings in Taipei City and New Taipei City, when residents turn on the faucets in their homes, they occasionally find that the water is mixed with yellowish sand, or has a peculiar smell and a white turbidity. Many people immediately thought that the water quality in the water plant had deteriorated, but in fact, reporters and water quality experts found that: More than 80% of the sources of water pollution come from the "tiny iron water tower (stainless steel water tower)" or "basement cement reservoir" on the top floor of the building that has long been lack of maintenance! If the water tower is not cleaned regularly, thick yellow mud, algae and even dead insects will be deposited at the bottom. Once the water inlet control switch around the water tower fails, it will cause a large overflow of the water tower to flood the residents on the top floor, or the motor will dry out and burn out, resulting in huge losses. Maintaining water tower equipment is a top priority to ensure the health of your family’s drinking water and the safety of electrical and mechanical equipment.
Fact check: Taipei Waterworks Agency's "semi-annually regular tower washing" standard procedure
According to the water quality management regulations of the Taipei Water Works Agency and Taiwan Water Supply Company, water towers and reservoirs in apartment buildings must be thoroughly cleaned at least once every six months (every 6 months). Qualified professional water washing tower manufacturers must follow the following five standard operating procedures:
- Draining the water tower and safety inspection before washing: Turn off the water inlet switch and drain the remaining water in the water tower. Ventilation and harmful gas (such as carbon monoxide, biogas) detection must be carried out before entering the tower to ensure the safety of tower washing personnel.
- High-pressure water gun and physical scrubbing: Use a high-pressure water gun to clean the inner wall, top plate and bottom of the water tower, and scrub with a soft brush. It is strictly prohibited to use high-concentration hydrochloric acid, sulfuric acid and other corrosive and strong acid chemicals, otherwise it will destroy the anti-rust coating (passivation film) of stainless steel, causing rapid corrosion and perforation of the water tower!
- Food-grade sodium hypochlorite disinfection: After scrubbing, use a low-concentration sodium hypochlorite solution (approximately 50-100 ppm) that meets food hygiene standards to spray and disinfect the tower wall without dead corners and let it sit for 30 minutes.
- Thorough flushing and drainage sampling: Rinse the disinfectant thoroughly with clean water, refill the water and collect water samples to detect free residual chlorine, turbidity and coliforms. Water supply can be restored only after passing the test.
Common electromechanical failures in water towers: float valve and liquid level controller (Lec) maintenance
The water tower can automatically control the amount of water entering and exiting, relying entirely on the surrounding electromechanical switch components. Common fault causes and solutions are as follows:
- The water inlet float valve (Float Valve) ages and overflows: The mechanical float valve relies on buoyancy to block the water inlet. When the float connecting rod is deformed or the internal rubber water-stopping gasket ages and hardens, the water level in the water tower is full but the water cannot be stopped. A large amount of tap water will continue to flow out from the overflow pipe of the water tower, causing the community's water bill to skyrocket by tens of thousands of yuan. It should be replaced in time with a stainless steel all-copper water-stop float valve.
- Liquid Level Switch failed motor and burned out:The liquid level controller senses the water level through two weights (A1/A2 or B1/B2) suspended inside the water tower, and controls the opening and closing of the basement pumping motor. When the controller coil is burned out or the weight rope is entangled and stuck, it will cause the water tower to have no water but the motor will not run, or the water tower will be full but the motor will continue to blindly pump water, causing the motor to overheat and burn.
Anti-pitting piping around water towers: Abolish sun-exposed PVC pipes and upgrade stainless steel insulation pipes
The water tower on the top floor is exposed to sunlight and ultraviolet (UV) for a long time, and the pipe material determines the durability:
| Types of pipes | Durability and physical property description | Maintenance recommendations and selection evaluation |
|---|---|---|
| Traditional gray PVC water pipe | Easily brittle and crack after 2-3 years of exposure, and easily broken by strong winds during typhoons | It is not recommended to be used for open-air pipelines on rooftops, as they can easily break and cause major flooding |
| 304 stainless steel thermal insulation pressure pipe | High pressure resistant, UV resistant, covered with thermal insulation layer to prevent water temperature from rising in summer | The best choice for rooftop water tower piping, with a service life of more than 30 years |
Conclusion: Regular maintenance of water towers protects residential health and property assets
Water towers are the final line of defense for residential water systems. Strictly implement the Taipei Water Works Office's regular tower washing standards every six months, promptly replace the aging water inlet float valve and liquid level controller, and upgrade the rooftop open-air pipelines to durable stainless steel pressure pipes. This can completely cut off water pollution and major overflow disasters from the source, provide families with clean and safe high-quality drinking water, and at the same time maintain the excellent quality of community properties.
The Ministry of Economic Affairs' latest "Regulations on Consumer Electrical Equipment Installation" and the key points of electricity safety in old houses
Due to the popularity of high-power household appliances (such as air fryers, microwave ovens, dishwashers, instantaneous electric water heaters, and IH furnaces) in recent years, the Energy Administration of the Ministry of Economic Affairs has revised the "Regulations on Consumer Electrical Equipment Installation" many times to strictly require the diversion and protection mechanisms of residential electricity circuits. Statistics show that more than 30% of building fires in Taiwan are caused by electrical factors, among which "old wire insulation deteriorates and short circuits", "socket contacts are oxidized and loose, poor contact" and "non-fuse switch (NFB) overloaded and failed to trip" are the three main fatal causes.
Old apartments in Shuangbei that are more than 30 years old have a total original designed power capacity of only 30A to 40A, and several rooms often share the same 1.6mm or 2.0mm circuit. In the modern standard safety configuration, kitchen electrical cabinets, bathroom equipment, and air-conditioning and heating machines must all be equipped with 5.5mm² dedicated circuits (single circuit and single socket). It is recommended that the main switch box be upgraded to a busbar (Busbar) integrated distribution board, and the total amperage is increased to 75A or 100A (a qualified electrical appliance contractor needs to be entrusted to Taipower to review the additional power capacity).
Residential electricity self-test and regular inspection checklist
- Appearance and temperature of the socket: Touch the outer cover of the commonly used socket lightly with the back of your hand. If it feels lukewarm or if you find that the plastic socket is yellowed and charred, or the plug is loose and shaking after being plugged in, it means that the internal copper plate clamping force is exhausted or the contact resistance is too high, and you should immediately cut off the power and replace it.
- Regular testing of leakage circuit breakers (ELCB): For leakage circuit breakers in humid places such as balconies, bathrooms, and kitchen sinks, regulations require that the "TEST button" on the switch be pressed once every 1 to 3 months to confirm that it can automatically trip and cut off the power supply instantly.
- Serial connection and overloading of extension cords are strictly prohibited: Extension cords should be purchased with 2.0mm thick wire diameter products that have CNS certification and automatic overload power-off protection. Do not share the same extension cord with high energy-consuming appliances to ensure zero hidden danger to life and property at home.

![[Regular cleaning and maintenance of the apartment water tower] The water from the building's galvanized iron water tower is turbid, or the float valve is malfunctioning and overflowing? Taipei Water Supply Service Tower Washing Specifications, Water Inlet Solenoid Valve and Liquid Level Controller Maintenance](/images/home-963347_1280.webp)

