How to save water in the laundry

One of the easiest ways to reduce your water consumption is to tweak your laundry routine.

Three tips to conserve water

1. Wait until there's enough for a full load

Most people wash about 3.5kg of laundry at a time, even if their machine can hold significantly more. By running your washing machine less frequently, you’ll save water as well as time, effort, detergent and power.

2. Don’t overload the drum

If the machine’s too full, it won’t be able to clean your clothes properly. Use your bathroom scales to work out how much a basket of laundry weighs.

3. Pre-treat heavily soiled items

This will help you avoid having to run a second wash.

If you’re buying a new machine

Get a front loader

Our tests have shown that, on the whole, front loaders use less water than top loaders.

On average, an 8.5kg top loader uses nearly 135L of water per 3.5kg load, whereas an 8.5kg front loader swigs a more modest 64L. If you did one 3.5kg load of laundry a day, the top loader would soak up about $185 (based on Watercare Auckland’s water charges) in water charges each year. A front loader, however, would consume just $88. The $97 saving could for pay for a whole year of laundry detergent!

Check the star rating labels in-store to find the most water-efficient models

Along with the star rating, you’ll see a “litres per wash” figure. Sometimes this differs significantly from what we’ve recorded in our lab. Often, this is because the programme selected by the manufacturer is not what consumers are most likely to use. In our tests, we use a “normal, cold” cycle or the closest approximation thereof. Also, we use a 3.5kg load, whereas the manufacturer’s test is carried out at full capacity.

Look for these water-saving features:

• Autosensing: Most modern washers automatically adjust the water level according to the load’s weight or level of soiling.
• Add item: A little door lets you add extra items or more detergent after the cycle has started, so you won’t have to do another wash for just one or two things.
• Fast wash: Some models will wash lightly soiled loads in as little as 15 minutes.

  

• Pre-wash: The machine will fill with water to soak laundry. After a set period, the dirty water will drain, and a normal wash cycle will begin. It’s like doing one-and-a-half washes instead of two full cycles.
• Eco cycle: It uses lower wash and rinse temperatures so less energy is required for heating. The water savings might not be significant, but you’ll definitely use less power. The trade-off is that eco cycles take longer and aren’t as thorough as regular programmes.

How about a washer-dryer?

When it comes to performance, washer-dryers are a mixed bag: the washer component is often very good, but the dryer is almost always inferior to a standalone unit. So unless space dictates that you can have one appliance only, is there another reason you should consider a washer-dryer? Yes: a combo has a lower water footprint than a washing machine and separate dryer set-up.

Minimising the carbon footprint

You might be aware of your “carbon footprint” as a measure of the greenhouse gases your lifestyle generates. But what about your water footprint – the total volume of fresh water you indirectly consume through goods and services?

Manufacturing two machines requires more resources (including water) than manufacturing one, so rolling a washing machine and a dryer into a single unit reduces the overall hidden water cost substantially.

If you’re not convinced of the (indirect) savings embedded in a two-in-one, bear in mind that washer-dryers use front-loader technology. If your new washer-dryer is replacing a top loader, you’ll notice the (direct) savings immediately.

Recycle wastewater

If you’re keen to take water conservation to the next level, consider recycling wastewater from your bathroom, laundry and kitchen. Once this greywater’s been treated, it can be used to irrigate gardens and flush toilets.

Installing a greywater system will conserve fresh water, but it’s expensive and not an easy retrofit (you’ll need consent, a plumber, and several thousand dollars). The systems use electric pumps to divert water to treatment tanks, so you’ll need to factor in the power costs, too.

You’re unlikely to recoup your investment, but greywater systems are great for the environment and can save a lot of water overall.

Note: It doesn’t include toilet waste. Also, kitchen wastewater generally isn’t used as it may contain dangerous levels of bacteria or grease that can block pipes. If you’re going to reuse laundry water, check that the chemicals in your detergent won’t cause harm.
Even after treatment, greywater must never be used for cooking, bathing, brushing teeth, swimming or drinking.