Commentary: Reducing household water consumption starts with the toilet bowl
The largest amount of water in a household is wasted in the toilet and this has increased since more of us stay at home. It’s time to rethink fittings in the loo, says climate activist Ho Xiang Tian.
SINGAPORE: Ask strangers on the street how much water they think a person uses per day at home, and the answers will range from 2 litres to 50 litres.
The answer that most people never got to: More than 140 litres per person, per day. This was something I used to do at outreach booths as part of my volunteer work with LepakInSG, a local environmental group.
We think we consume much less water because we only think about the water we drink, and severely underestimate the water used in other activities like showering, washing the dishes, and flushing.
According to PUB, households account for about 45 per cent of Singapore’s water use, which is significant compared to other metrics like waste generated (25 per cent) and carbon emissions (6 per cent).
Recent PUB figures show that household water consumption spiked to 154 litres per person per day in 2020, compared to 141 litres in 2019.
The increase in household water consumption makes sense, as most stayed home during the circuit breaker, and continued to spend more time at home after.
PUB has said that average water consumption has not returned to pre-COVID-19 levels. This is because water previously used at work or in school is now used at home.
ENTER THE TOILET BOWL
One culprit in how much water is used is the humble toilet bowl. The most inefficient water closets in Singapore use 9 litres of water per flush. The most efficient ones use 3 litres for half a flush and 4.5 litres for a full flush.
Many are stunned when they learn about this.
In contrast, the most inefficient urinals use 1.5 litres of water while the most efficient ones use less than 0.5 litres of water.
This means that even the most inefficient urinal will use less water than the most efficient water closet at half flush.
Assuming most toilet flushes are for liquids rather than solids, a lot of water can be saved if all liquid waste went into a urinal rather than a toilet bowl.
But urinals are present in less than half the toilets in Singapore, based on the assumption all public female toilets, handicapped toilets, and home toilets don’t contain urinals.
Most public male toilets offer a choice, and most who enter would pick the urinal. Public female toilets unfortunately don’t offer this choice and those who enter simply use the toilet bowl.
This means that on average, public female toilet users in Singapore use 3 litres to 4 litres more water for peeing than male toilet users. It’s not their fault that they use more water to flush, it’s just the way that toilets are designed. In most homes, there is no choice for everyone as well.
This suggests that the toilet bowl is a limiting factor in our nation’s water saving efforts.
WHAT ARE ALTERNATIVES?
An average human relieves himself about six to 10 times a day. Assuming people used to pee half the time when they were away from home, this translates to 12 litres to 20 litres more household water consumed per person per day, and overall higher consumption of water for flushing nationwide.
Most homes only have toilet bowls installed. This means that the only alternatives to flushing at least 3 litres down the drain is to pee in the shower, share a flush with a housemate, or to use a chamber pot, all of which are unhygienic and highly unappealing options for most of us.
What could be an alternative to the toilet bowl at home?
One alternative could be unisex urinals in homes, so everyone can reduce water consumption from flushing after peeing.
A urinal for homes would need to be designed, taking into account the space constraint in HDB toilets, and the challenges of installing it into existing water services and sanitary plumbing.
It would be a lot of work, but a well-designed unisex urinal could help to cut household water consumption.
But fitting a urinal into a cramped toilet would not be ideal.
Toilets in HDB flats range from 3 sq m to 4 sq m, with bigger HDBs generally having bigger toilets. This makes it hard to have a standardised urinal design for all HDBs, especially those that are already built, but this is where we need to think out of the box (or bowl in this case).
One possibility is installing a urinal over the shower drain.
Cost might be another factor, but would PUB be willing to install urinals in households for free to help save water, similar to what is being done for households with non-water efficient fittings?
Since we replace water closets in older homes with more efficient ones, installing an additional urinal in all homes to save even more water is not an impossible task. New homes could also come pre-installed with urinals to reduce household water consumption.
FEMALE URINALS AND HOW THEY WORK
Of course, not everyone is comfortable using a urinal, but this should not be that daunting, and there is always the option to use the familiar toilet bowl.
Acceptance of urinals in household toilets could spur acceptance of urinals in public female toilets in the future.
The use of a urinal for females has been trialled in other countries. There, female urinals have been designed for standing with the use of a funnel, or for sitting like a conventional toilet, with a partition for privacy.
France and Germany have used temporary female urinals at large scale public events, while the Hong Kong Toilet Association previously pushed for female urinals in public toilets. However, lack of privacy and unfamiliarity with female urinals have resulted in scepticism.
My female friends have shared that some factors to consider would be privacy, periods, general toilet cleanliness, and type of clothing, for instance, if one wears a jumpsuit it can get troublesome.
For these reasons, large-scale adoption is not seen in the world just yet. On the bright side, Singapore could be on the cutting edge of household toilet innovation if we find a way to make this happen.
We have found a way to deal with water being an existential issue. With more of us staying home, our water issues will never really go away. Every drop saved is one less drop that we need to extract from NEWater and desalination plants.
To this end, PUB’s efforts are not in vain – over the years, changes have been made from mandating the maximum flush capacity of toilet bowls to implementing the Water Efficiency Labelling Scheme.
These have increased household water efficiency, but more can be done to reduce our household water consumption.
If the humble toilet can be redesigned to suit all genders and reduce water usage, it could be a game-changer for household water consumption in Singapore.
Was COVID-19 the jolt we needed to make us rethink our hygiene habits? Jaime Ho speaks with Edward D'Silva of the Public Hygiene Council and Jack Sim of World Toilet Organization on CNA's Heart of the Matter podcast:
Ho Xiang Tian is the co-founder of informal environmental group LepakInSG.