The document summarizes the water treatment process at Te Marua, which supplies water to Wellington, New Zealand. Water is collected from the Hutt River and chemicals are added to help separate dirt particles from the water. The water then undergoes filtration through charcoal filters before disinfection. Sludge removed from the water is dried and transported away. The treatment process takes a long time to ensure the water is clean for human consumption and health benefits.

1. How Water Travels Through The Treatment Plant
Felix Williamson

2. Contents
Page
Contents……………………………………………………………………………………………………………………… 1
Introduction………………………………………………………………………………………………………………… 2
Collection…………………………………………………………………………………………………………………… 3
Separation…………….…………………………………………………………………………………………………… 3
Filtration…………………………………………………………………………………………………………………… 3
Sludge………………………………………………………………………………………………………………………… 4
Time and Energy……………………………………………………………………………………………………… 4
Health Benefits………………………………………………………………………………………………………… 5
Reflection……………………………………………………………………………………………………………………… 6
References…………………………………………………………………………………………………………………… 7

3. Introduction
This is a report on how the water goes through a treatment plant. Te Marua
have two big storage lakes in Upper Hutt. This is for us to use if there is a
storm, and the Upper Hutt River is too muddy. The steps Te Marua use to treat
water are sieve, coagulation, flocculation, separation, filtration and disinfection.
Te Marua supplies: Upper Hutt, Manor Park, Stokes Valley, Porirua and the rest
of Wellington as far as Karori. They also supply 40% of Wellington’s water
every year. They are a very big treatment plant because of this.
Wellington uses 1035 million litres of water a day. We have used a lot less
water since last year because of the drought we had. This is a good sign.

4. Collection
Water is collected from the Hutt River six kilometres away from the
Treatment Plant. It is then brought in and swirled around with some PACL
which is a type of chemical that you put into the water to bring the particles of
dirt together. It is then brought through two tanks to slow it down so that the
chemical will work.
Separation
After that it settled, so that the sludge that comes off the rocks from the
Hutt River can combine together. They then sink to the bottom of the tank
where they are separated from the water.
Filtration
Then it flows through the pipes to the filter and gets filtered through the hard
charcoal. If they find too much bacteria in the water they backwash it, which
means that they empty the filter, then blow air from the bottom. So that
moves all the dirt out and cleans it you have three or more filters because of
the backwashing. You have to have two filters working to get enough water.

5. Sludge
There has to be somewhere for all of the sludge to go (Where does it go?). It
goes to a big tank for the day. At the end of the day people check which is the
dirtiest then they get the clumpy stuff and dry it, put it on a conveyer belt, put
it into a bin that is massive and get it taken away. They use three bins a day.
Time and Energy
Treating the water should get rid of all the dirt, but now always. The process
of treating the water takes a long time because we need to make it really clean
so we don’t get sick. There is no good way to get rid of all the contamination in
the water that Te Marua gets for treating.

6. Health Benefits
Flouride is the chemical we clean our teeth with. Te Marua put it in to the
water to provide dental health benefits. It makes the water taste a bit better
too.

7. Reflection
The water we drink is clean for us to use.
I would like Te Marua to be able to filter grey water and for us to be able to
drink it. This would take a lot of time and energy plus a lot of money. But the
way we use water now there won’t be any water left in 300 or 400 years. So
filtering grey water would save a lot of the water that is wasted down our sinks.

8. References
Te Marua Website
Wikipedia
Google Images
YouTube