What Goes Down Our Kitchen Sink

What Goes Down Our Kitchen Sink A hands-on workbook for pre-school to middle schoolers, demonstrating through experimentation the consequences of what we send down our kitchen sink.

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Down Our Kitchen Sink Hi Kids! I’m Piper the Pipe Protector!

It’s not just in the bathroom that people send lots of different things down the drain. This happens in your kitchen, too. Just like in the bathroom, some things are supposed to go down the drain and others are not. But it can be really difficult to tell the difference. It’s especially hard to know what happens to all that stuff because we never get to see it again once it goes down the drain.

This activity is designed to help us actually see what happens to all the stuff we might send down our kitchen sink.

FIRST, make sure you have all of the items you will need for this activity:

1 clear plastic or glass container, lid optional.

Recycled food containers work great! You can use a cleaned jar of: peanut butter, or salsa, or jam, or tomato sauce, or milk, or juice. You can even use a simple plastic cup.

Something to stir with. This might be a spoon, or a straw, or a coffee stirrer, or a stick.

Foods that might go down your kitchen sink.

Restaurant food packets are great because you only need a little bit of food. This could be ketchup, or mustard, or mayo, or bbq sauce, or ranch dressing, or whatever you can find!

Water.

Pen, colored pencils, crayons, or markers for sketching.

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Getting Set Up NEXT, prepare your materials for the activity:

Prepare your containers.

Wash them and remove enough of the label so that you can see clearly into them.

Fill your containers.

Fill half way with water.

Gather the food items you plan to use.

Some towels for cleaning up are nice to have, too.

Gather your containers, food items, stirring tool, and your sketching supplies together.

Food and Water

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LET’S BEGIN: What happens to our food when we put it in water?

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Take one of your containers filled halfway with water. Open the lid if there is one.

Take your stirring tool and spin your food item gently in the container (make sure not to spill). Go slowly.

That way you can watch what happens while you stir.

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Take your food item and squeeze a small amount into the container. Make sure to do this slowly so you can watch closely what happens.

Put your container down in front of you and look closely at what happened.

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Draw What You See DRAW WHAT YOU SEE:

Sketching is a tool that scientists use to pay close attention. It helps us focus on details we might miss.

Feel free to use colors and labels and words in your sketches. The more detail the better!

I encourage you to take your time sketching your food. We never really get an opportunity to see what happens to our food after it goes down the drain!

Write What You See

WRITE WHAT YOU SEE:

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...You can write things that

you notice about your food. ...You can write questions

that you have. I bet that many of your questions are things you can try right now! . You can write what your

food reminds you of.

. You can do this again

with a different kind of food. Every food behaves a little bit differently in water. *Note: It’s much easier to see what happens if you put them in a different container, instead of adding it to your current one. That way you can compare them if you want.

EXAMPLE

Here’s one way a drawing might look. Use your own words and drawings to describe what you see.

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Cleaning Your Water If we asked you to try and clean the food out of your water, but leave the water in your jar, how do you think you would get the food out?

DRAW OR WRITE WHAT YOU MIGHT DO. You can even try to do it right now!

Now, how do you think you might clean your water if there were two kinds of food in it?

What if there were lots of different kinds of foods in your water? What might you do then?

How Do We Clean Everyone’s Water?

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How can we possibly clean all of the different foods out of our water at once?

If only one kind of food went down our drains, the job of cleaning our dirty water might be simple. But we know that lots of different kinds of foods go down the drain at once. Which means cleaning our dirty water is complex.

We have a process for cleaning everyone’s dirty water. But before we tell you what we do, there are a few things we need to know: All foods behave differently in water, but there are a few patterns that we can see (and you can try!)

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Some foods will float to the surface.

Some foods go into suspension, which means they spread out evenly in water.

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Other foods will sink to the bottom.

And some foods hold their shape and they don’t break apart.

8 Why Are These Differences Important?

These patterns can help us think about how we might clean our water. In order to design a way to clean all of the different solids we find in our dirty water, we need to know how they behave.

Here is a diagram of one of the treatment tanks at Central San, cut away so you can see inside. This shows how the solids that come to the plant are removed from the water:

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For solids that go into suspension, we need extra help. We use bacteria to eat the solids that are floating everywhere in the water.

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For solids that float, we can skim them off the top.

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For solids that sink, we can scrape them off the bottom.

For solids that hold their shape, sometimes they can get stuck in pipes that lead away from your home before we have a chance to clean them :(

How Can You Help?

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So What Can You Do To Help?

That’s a great question! There are actually a few things you can do everyday.

The less food that goes down the drain, the better.

So try to eat all the food you take on your plate. If you have leftovers, you can put them in the compost or the trash.

Some foods we don’t want going down the drain at all.

These are foods like Fats, Oils, & Grease. These foods hold their shape and can get stuck underground before we have a chance to clean them. Definitely put those directly in the compost or trash! You can even wipe down pots, pans, and utensils before you wash them—that will help a lot, too!

TAKE A PICTURE OF YOURSELF DOING THESE THINGS.

For privacy purposes, make sure your face is NOT in the photo. Then send it to us! You can print out your photo and paste or tape it over our example here, then cut out the whole page on the dotted line, fold it and mail it to us. Or you can email a digital photo to blavender@centralsan.org. We’ll put our favorites online at: centralsan.org/learn.

If you would like to receive a small prize for your efforts, please include your return address in your email.

This is an example of the type of photo you can provide. Make sure there are no full faces showing in the photo.

Paste or tape your printed photo inside the blue box here.

Return Address:

Fold Here

Place Stamp Here

Education Department Central Contra Costa Sanitary District 5019 Imhoff Place Martinez, CA 94553