6 ways you might be polluting water without realising

The state of our waterways is often in the headlines – and for all the wrong reasons.

In October, the regulator Ofwat ordered water companies to issue bill rebates to customers over their woeful performance on sewage leaks and pollution. And industrial agriculture has been in the spotlight for the disastrous environmental impact its polluting of UK rivers has had.  

It may feel, as individuals, like we have little impact on what goes into our water. But domestic households contribute to water pollution and its associated environmental damage in ways you might not be aware of. 

There are actions you can take to reduce the problem – here are six key tips to follow.

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1. Think about what you flush

It's crucial not to flush anything other than toilet roll down the loo. Flushing sanitary products and wet wipes can block sewage pipes – either in your home or further down the line. 

A ban on the sale of wet wipes, which contain plastic, is set to be in place by the end of 2024. But just because other wipes are plastic-free doesn't make them flushable. In fact, the Fine to Flush logo is being removed from packaging, due to concerns about that claim.

These wipes can also cause blockages – and they're not designed to break down as easily as the 'biodegradable' label might suggest, resulting in them accumulating in rivers. So make sure you put all your used wet wipes in the bin.

Don't flush unwanted medicines down the loo, either – your local pharmacy will dispose of them for you.

Find out more: plastic-free wet wipes and reusable alternatives 

2. Consider what goes down the sink

The combination of wet wipes that don't easily disintegrate, plus fat and grease from kitchen sinks, creates monstrous 'fatbergs' in our sewer systems. 

Cooled oil and fat can block up your household pipes, too. 

Instead of putting it down the sink, you can put small amounts of cooking oil and grease in your food waste recycling bin. If you don't use one, or don't have access to food waste recycling where you live, put cooled oil in a secure container that you're throwing away anyway, and dispose of it in your general waste bin. 

The Recycle Now website is a good source of information to help you to determine what to do with specific recyclable and non-recyclable items if you're not sure how to get rid of them.

The cleaning products you use in your kitchen and bathroom also make their way into your pipes and drains, so take time to read the label to find out what's in your household cleaners and other chemicals. Make sure they are not labelled 'hazardous to aquatic life'. 

The exception to this is eco-friendly cleaning products that are sold as concentrates, which you then dilute at home. The packaging may say it's hazardous in reference to the concentrated product, but if you dilute it as instructed, then it should be safe. Choose products that are biodegradable and which supply information about how long they take to break down.

Our tests on dishwasher tablets, washing-up liquid and washing powders and detergent include examining the eco-credentials of the ingredients and packaging used. 

Only those that have a reduced environmental impact compared to alternatives – and that perform their core job of cleaning well – can be deemed a Which? Eco Buy.

3. Buy less synthetic clothing and reduce how often you wash it

Synthetic clothing made from fossil-fuel-based fibres, such as acrylic and polyester, is continuously releasing plastic microfibres – tiny plastic fragments – into the atmosphere, but the laundry is the most direct way these get into waterways.

The Plastic Soup Foundation reports that microplastics that shed from synthetic clothes when they're being washed account for up to 35% of the plastic particles in our oceans. A single laundry load can produce millions of fibres that are washed down the drain.

There have been calls in the UK and EU to fit all new washing machines with microplastic filters. In the meantime, you can:

• Wash clothing less often
• Wash a full load, at a lower temperature and on a shorter wash
• Use less detergent, as this causes less friction, which causes fabric to shed – liquid and gel detergents also create less friction than washing powder.
• Try a device such as a Guppy bag, which you wash synthetic clothes in that helps to catch microfibres, or a laundry ball or filter that you can fit retrospectively to your machine.

Washing machines and tumble dryers use a lot of energy to run. For more information on energy efficient laundry visit our advice on energy efficient washing machines.

4. Reduce your plastic use

Plastic ends up in our oceans and rivers through direct littering, products we flush away (including microplastics) and from landfill sites (lightweight plastic can be dispersed by wind and weather, or lost during transport to and from these sites). 

The charity Thames21 has a citizen science programme to monitor plastic pollution. Its 2020 report found that nearly two thirds of all lightweight identifiable plastic in the tidal Thames foreshore came from five single-use items – food wrappers, cotton bud sticks (cotton buds containing plastic have now been banned), drinks bottles and lids, cups and takeaway containers.

Recycling any plastic you use properly is obviously important, but reducing how much single-use plastic you use is the most effective step you can take in stemming the tide of plastic pollution entering our waters.

For more on recycling plastics and other materials, read our guide on how to recycle in the UK.

5. Leave a natural garden with drainage

Where you have a choice, it's important to keep as much ground as possible permeable (meaning rainwater can absorb into it). That means keeping outside spaces natural – with earth and grass rather than tarmac, concrete or paving. 

This helps to absorb flood water and run off during storms and heavy rainfall. In turn, that prevents overloaded sewers and stops dirty water flowing into our rivers and streams. 

Gardeners should also limit your use of fertilisers and pesticides, particularly if rain is forecast. The Royal Horticultural Society generally advises avoiding using these altogether in late summer or autumn (aside from autumn lawn feed) when they may be washed off and lost over winter.

Find out more: alternatives to weed killers for paving and paths

6. Keep surface water drains clear

Keep surface water drains and gutters clear of leaves and other debris to ensure water flows correctly and systems don't back up. Using a water butt can also help reduce the pressure on drainage systems.

You should also be very careful of what you put down surface and storm drains – those that collect water from roofs, driveways and roads. Unlike waste water drains, which are piped from your home and carry sewage, this water is left untreated and goes directly back into waterways. 

Dirty water that contains chemical cleaning products and bleach (water from mop buckets, for example) should go down your waste water drains instead, where it will be treated at a sewage works.

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