NCWR

About NCWR

Do you know about grey water?

In a nutshell

In this activity we find out what is “greywater”, how it is produced and how it can be reused!

45 min

12-13 years old

In class

Our objectives

In this activity you will:

  • Explore, greywater, one of the “non conventional” water resources.
  • Learn how greywater gets cleansed.
  • Discuss which are the uses of the recycled greywater .
  • Consider optional practical greywater applications for your home and school.

Play & Learn

Can we reuse the soapy waters after washing of our hands?

Water-readings

What is grey water?

Greywater is the household’s wastewater, other than that coming from toilets (), meaning the wastewater from the the sink, shower, bath-tub, and laundry machine. This wastewater can be relatively easily, cleaned and reused.

Modern technology offers a lot of options for an effective greywater treatment. The most popular greywater systems treat water coming from the showers, bathtubs, washbasin and laundry machines, but not that from the kitchen sinks and the dishwashers, as this requires a more complex and costly technology.

Play & Learn

Which of the following activities produce greywater? Check appropriately.

Actually, many car washing stations today are equipped with the system for collecting, filtering/cleaning and reusing the water used.

Water from the swimming pool is not considered as greywater because it contains a lot of chlorine that can be toxic.

Water after taking a shower it mainly contains remains of soap, shampoo, shower gels, etc that can be relatively easily removed through filters

This is “black water” and it goes to the sewage system (and through that to the wastewater treatment plant).

This water contains big amounts of grease and oils and is more complex to be recycled.

This water contains remains of detergents that can be easily removed through filters

This water contains big amounts of grease and oils and it is more complex to be recycled.

It contains mainly dust and soap residues and can be easily cleaned.

Water-readings

How do we treat greywater?

Greywater treatment is realised through an automatic closed system that includes pipes, pumps, filters and tanks. Firstly, the greywater from the washbasins and the shower/bathtub is collected through pipes and led to filters that hold the large suspended solids.

Then, this water is led to the treatment tanks where it is aerated, re-filtered, and to eliminate any harmful microorganisms.

Finally, water is stored to a tank and is ready to be used both inside and outside the building, with the help of a . Attention, the treated greywater should not stay long in the storage tank. If it is not used in the next e.g. 24 hrs the stored water is channelled to the the sewage network.

The entire system is closed and automatic, so that there is no human contact for safety and hygiene reasons. There is a control unit and the users need to maintain the system (change filters, add disinfectants, etc.) according to the manufacturer’s provisions.

How can we use the treated greywater?

The treated greywater  can be consumed for uses that do not require crystal clear water; certainly not for personal hygiene (bathing, showering) cooking or drinking! The treated greywater is mainly used in the toilet flushing and for watering the garden. Actually we can use it in irrigating trees, residential green spaces and gardens but it is not recommended for irrigating edible leafy vegetables. In fact, it is advised that the watering process should be done through pipes feeding the root of the plant, avoiding sprinklers and open channels. The treated greywater should not be used for outdoor recreation (filling pools or playing in sprinklers).

A household that recycles its greywater can save up to 1/3 of consumption from the water supply network!

Stop and wonder

DISCUSS In your groups


  • Since we can achieve such a great water saving with a greywater system, why don’t we all have such systems in our houses?
  • Why do we avoid watering the leafy vegetables with treated greywater?
  • When irrigating with treated gryewater, why do we opt for automatic hose system and avoid open water channels?

 

Play & learn

Drag and drop the parts of a greywater system within a building.

 grey-water-system quiz-hotspot
1
2
3
4
5
6
7
8
  • 1 1 filters
  • 2 2 disinfection
  • 3 3 control unit
  • 4 4 storage tank
  • 5 5 aeration pump
  • 6 6 sewage network pipe
  • 7 7 source of greywater
  • 8 8 treatment tanks

Water shares


Water meter

I liked this activity . . .

Way forward

Dive in…

the Rainwater harvesting , the Wastewater treatment or the  Desalination unit if you want to know about other non-conventional water resources.

Examples of greywater systems if you want to know more  about an actual greywater system installed.

Go back to the homepage!

The water basins

Water in the city

Desalination

Do you know about grey water?

Rainwater harvesting

Greywater recycling in practice

Wastewater treatment

The water cycle in a bowl!

Waterworks through time

Climate change challenges

Rainwater Harvesting Systems in practice

Reduce-Reuse-Recycle

Water resources

Where do I begin?

The water basins

In this activity we learn what a water drainage basin is and why it is important for the experts to study it.

Continue!

Water in the city

What is the "urban water cycle"? Which are the important aspects of water management within a city environment?

Continue!

Desalination

Let's find out how sea and brackish water can become a freshwater resource!

Continue!

Do you know about grey water?

Let's find out what "greywater” is and how we can use it!

Continue!

Rainwater harvesting

Can do we collect rainwater? And how do we use it? Let's find out!

Continue!

Greywater recycling in practice

How a grewywater system is installed? Let's find out!

Continue!

Wastewater treatment

In this activity we learn about how wastewater is treated and what we can do with the treated water.

Continue!

The water cycle in a bowl!

Let's travel within the water cycle!

Continue!

Waterworks through time

Let's discover the story behind the historic fountains, cisterns and aqueducts of our town!

Continue!

Climate change challenges

Time to discuss about climate change, causes and impact and how we can cope with it.

Continue!

Rainwater Harvesting Systems in practice

What are the various types of rainwater harvesting systems? Let's find out more about them!

Continue!

Reduce-Reuse-Recycle

What is my water footprint and how can I reduce it?

Continue!

Water resources

Discovering the water resources of our region.

Continue!

Where do I begin?

Let's see why it is important to know about water in our region.

Continue!