June has arrived and is bringing us the ‘hottest ’ summer ever. We are in a stage where the demand for water is very high. Do you know how much water we consume every day? Which measures contribute to improve water efficiency? Here is the quiz, and you will find the answers in our article.

How much water does a human being use per day in urban area?

How much water does an office building with 1000 employees use per day?

In daily family life, water consumption is mainly related to faucets, showers and other sanitary ware. Using tap one minute can consume 5-7L water, showering a minute 9-12L, single flushing the toilet can go up to 6L.  According to our research on the water consumption habits of more households and the multiple data collection, in some more developed cities with relatively rich water resources, a person can consume about 300L of water per day. Maybe you have no idea of what it means, then we can take a look at the situation of water resources in China.

China is one of the most water-scarce countries in the world. The per capita water resource is less than 2,100m3, which is only 25% of the world’s per capita level. Under severe water shortage conditions, China’s water efficiency is very low, yet water recycling & reusing rate is less than half of that in developed countries.

Facing such a serious situation, what good practices can we adopt in the design stage to reduce indoor and outdoor water consumption and improve water efficiency?

Water saving for building assets

According to the design standard of water quota for office buildings, the average daily water consumption for an office building of 1,000 occupants & utilization 8-10 hours per day is 40,000 L.

As a designer or a building’s owner, maybe you are conceiving a high water efficient building or you want to improve your existing building to a “zero water consumption” assets, which measures are applicable?

Reduce – recycle – reuse

1. Water metering, BMS water monitoring and controlling

Install sub-meter to monitor each water-consuming plant for divers’ use (sanitary, kitchen, cleaning, laundry…)  and connect to BMS for monitoring of water consumption and detect water leakage. BMS could also connect to electromagnetic valve for controlling the water flow.


2. Water efficient fixture

Choose water efficient fixture and new-tech waterless fixture.

  • Waterless urinal

This kind of urinal needs no flushing and can save quantities of water and significantly reduce sewage and maintenance cost.

  • Tank-less toilet

Tank less toilet is a new type of water-saving toilet without tank, which uses municipal water or internal pump to flush directly. It makes a full use of water pressure from municipal pipe. According to infrared sensor, the full flush use 2-3 L/flush and half flush use 1-2L/flush.

  • One piece hands washing sink toilet

This type of toilet lets you wash your hands with the water used for flushing. The water after washing hands will fill the tank for next flushing.

  • Automatic faucet and/or aerator

Use automatic faucet and /or aerator to avoiding unnecessary water running.


3. Water treatment and recycling system

  • Rainwater harvesting system

Rainwater harvest system refers to the whole process of rainwater collection and reuse. The rainwater cistern could be installed  outside or at the basement. The collected rainwater could be filtered and used for replenishment of indoor water reuse.


  • Greywater recycling system

Typically, greywater treatment is used as primary greywater treatment to remove dissolved and suspended biological matter, followed by ultra-filtration to prevent particles, bacteria and viruses of passing through. Ultimately, greywater can be disinfected to ensure residual disinfection at point-of-use.



  • Complex water purification system

The complex water purification system is more like a bespoke process which treats the water according to the demand of users for different end use. More performant devices such as Ultraviolet disinfection and chlorination equipment are needed and the quality of treated water must get through a series of testing to conform with the relevant regulation before getting in contact with human beings.


Want to get more information about water efficiency strategies?  please do not hesitate to contact us at contact@teraochina.cn. We will be very happy to help you to optimize the water efficiency and sustainability of your assets.

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