1 of 45

Value of Water

Engineering Field Day

Download the activity guide here

2 of 45

Where does water come from?

In Hawaii, most of our water is pumped from the underground water table or stored in mountains.

3 of 45

Where does your water come from?

Visit the Board of Water Supply website to find out

https://www.boardofwatersupply.com/water-quality/water-quality-report

4 of 45

5 of 45

https://watersworthit.org/

Our lives and communities are built on clean water and the infrastructure that supports it. It’s so reliable that we might not give it—or the impact of our actions—a second thought.

6 of 45

https://watersworthit.org/

We all consume water and create waste every day. Making smart choices helps us sustainably reuse water to protect the environment and the systems that keep it flowing.

7 of 45

https://watersworthit.org/

Water professionals around the world work every day to recover resources and provide clean water to protect our health, environment, economy, and quality of life.

8 of 45

https://watersworthit.org/

Water and wastewater treatment has saved millions of people all but eliminating waterborne diseases and advancing the health of our communities.

9 of 45

https://watersworthit.org/

Water must be recovered, recycled, and returned to the environment. Supporting innovative solutions and technology helps us transform operations for greater efficiency, productivity, and long-term sustainability.

10 of 45

What are some ways that water can get contaminated?

Storm water can pick up trash from cities, chemicals from factories, motor oil from roads, fertilizers and animal waste from pets.

Wastewater contains human waste, soaps, and chemicals we wash down the drain or toilet.

11 of 45

Why is it important to clean water before returning it to the environment?

Cleaning wastewater before it is released into the environment helps keep the oceans and rivers clean. This helps keep wildlife and the environment healthy.

12 of 45

Let’s learn how engineers make water safe to return to the environment!

Gather Materials:

13 of 45

The problem or challenge

How do environmental engineers remove contaminants from water before it goes to the ocean?

14 of 45

The hypothesis (or prediction)

What do you think will happen?

15 of 45

How can we tell if water is clean?

Visual?

Smell?

Touch?

16 of 45

17 of 45

Step 1 - Screening

Bar Screen

18 of 45

Which “contaminants” do you think will be caught

by the filter?

Let’s find out!

19 of 45

Step 1 - Screening

20 of 45

Discuss your observations of the screening process

21 of 45

Wastewater Treatment Plant Screen

22 of 45

23 of 45

What will happen if we let the water sit still?

24 of 45

Step 2 - Settling

25 of 45

Settling is a slow process, so engineers design LARGE tanks called clarifiers to give particles enough time to settle

26 of 45

Discuss your observations of the settling process

Which particles settle?

Are they smaller or larger? Why do you think that happens?

27 of 45

28 of 45

Step 3

Aeration Tank

We add air to the wastewater - called aeration. The air allows microbes to feed on organic material, forming bigger particles which easily settle out.

29 of 45

30 of 45

Step 4 - Filtration

Filter

31 of 45

Do you think the water will be clean after we filter it?

Let’s find out!

32 of 45

Step 4 - Filtration

33 of 45

Discuss your observations of the filtration process

How long is it taking to filter?

Is it faster or slower than the screen? Why do you think that happens?

34 of 45

Wastewater Treatment Plant Filter

Unfiltered Water

Filtered Water

Filter

35 of 45

Wastewater Treatment Plant Filter (Clean side)

36 of 45

Is the water clean now?

Screening, settling, and filtration remove sediment.

But how do we remove the bacteria you can’t see?

37 of 45

38 of 45

Two types of disinfection

39 of 45

Two types of disinfection

Chlorination uses a type of bleach. A stronger version of what you use to clean your house. But chemicals can be dangerous to work with.

Ultraviolet (UV) is a type of light. There’s even UV disinfection boxes to inactivate germs growing on the surface of your phone!

40 of 45

Step 5

41 of 45

42 of 45

Aha! My discoveries

What did you learn after testing?

  1. Which contaminants were removed and which contaminants are still in the water?
  2. Did certain materials work better for cleanup than others? Why do you think that is?
  3. What other tests could we do to check the purity of the water?

43 of 45

Engineers keep people and the environment healthy.

44 of 45

Conclusion

How do environmental engineers remove contaminants from water before it goes to the ocean?

Engineers protect the environment by designing treatment systems with multiple steps to remove contaminants.

45 of 45

How can we conserve �(protect and save) clean water for future use?

What can engineers design to help conserve our water?