With so much unknown about which way water flows, we turned to making a model to explain how this works.  We pulled out a tablecloth and some spray bottles to create Chicago's landscape, which is pretty flat.  

So we put a whole bunch of things UNDER the tablecloth to create areas of higher elevation and areas of lower elevation.  We recognized that Chicago's landscape doesn't look like this (we made some mountainous areas for sure!), but the different heights of the land helped us see that these differences in how tall the land is affects how the water flows on it.

We recognized that this didn't answer our wondering about which way the Chicago River flows (into or away from our suspected drinking water source of Lake Michigan).  So we're thinking that someone has to measure how "tall" the land is or how deep various bodies of water are. In fact, some students suggested that there are elevation readings recorded to tell us how high places are compared to others. Something like "above sea level."

Mrs. Brinza has committed to finding elevation data for areas in Chicago!  Check back soon as we figure this out!

We wanted to know more about Chicago's wastewater treatment facilities and where the water goes after it leaves the facilities. We came to consensus from using Google Maps on where Chicago's treated water goes.

We decided that it's the Chicago River!

So this got us thinking that even though we know the treated water goes into the Chicago River (or various parts of it--North Shore Channel, Chicago Sanitary and Ship Canal, South Branch/North Branch, etc.), we don't know which way the Chicago River goes as it relates to its connection to Lake Michigan.  Does Lake Michigan flow into the Chicago River?  Or does the Chicago River flow into Lake Michigan?

We are thinking heavily about this for a few reasons:

1. We've heard we get our drinking water from the lake.  Treated water still has lots of dissolved stuff in it, along with bleach and bacteria.  Does this mean the lake is really dirty if the water from the Chicago River flows into Lake Michigan?

2.  If the Lake flows into the Chicago River, is the lake losing water that would otherwise get used for drinking?

3.  If the river flows one way, and keeps receving treated water from other WWTFs, does the river get really, really dirty as it continues to flow?

And this circled back to...we don't know how the water flows!!!  We have to figure that out!

After figuring out how wastewater treatment facilities get out a good majority of dissolved solids (Federal Law states 85% of dissolved solids must be removed), we turned to our Driving Question Board to see what questions we could answer. We've figured out A LOT about dirty water!

But we're still left with more questions that have surfaced!  So we added new questions to the DQB, and two stuck out to the classes, which seem to focus on the next part of what we've figured out so far:  Where does water go after the WWTF?  Is it always a river? What about here in Chicago?

So we turned to using Google Maps again, looking for nearby bodies of water closest to two wastewater treatment facilities we've identified in Chicago: O'Brien and Stickey.  Here's some screenshots of the areas around and connected to bodies of water that we saw near the two wwtf.  We'll be trying to come to consensus tomorrow about where we think Chicago's treated water goes!

So we've truly figured out that our dirty water contains many, many, many dissolved solids.  We're really concerned with how they get out these particles, especially since all the methods we used to clean our dirty water didn't work.  There's lots of questions around how we can get out the dissolved stuff!

Since we can't go to the WWTF, we decided to turn back to the help of London and NYC who have documented their processes in dept. From here, we figured out a lot, especially since we know so much more about dissolved particles in the water!

We've come back together after some time off and are moving forward trying to figure out what happens when various substances are in water.

From our microscope, boiling, evaporation, and weight tests, we have finally come to an agreement about what happens to some substances when they enter water.  We think they dissolve, and that dissolving means the following:

1.  A solid enters a liquid (such as salt into water).

2. Over time, the solid breaks down into smaller pieces.

3. These pieces are so small we can't see them with our naked eyes, but looking at the water and substance mixture under a microscope we see they are still there, just much smaller than before they went into the water.

4.  None of the substance disappears!  We can account for all the substance because we weighed it beforehand and after and it weighed the same.

5. The substance's small particles are spread out everywhere in the water, otherwise we would see it!

Our initial models to explain this looked like this:

As you can see, we didn't have agreement on what this looked like from a zoomed-in perspective.  We had a deep discussion about what was really happening to the size of the pieces of the substance dissolving, and then we began to think more deeply about water.

In each student's models, everyone represented water as this whole piece.  After using some play-doh, we began to see how a big piece of play-doh doesn't behave like liquid play-doh. However, by breaking the play-doh up into small pieces, it began to behave like the water in the cup! This helped support our ideas behind solids being made of particles, and since solids can become liquids, liquids must be made of particles, too!

Water being made of particles also got us thinking about how water ALWAYS passed through any of the filters we used when we attempted to clean dirty water ourselves.  Since all those filters had holes, and some of the holes were really tiny, we're thinking that water's particles must be smaller than any of the microscopic holes in the filters we used.

Our next steps:  Now that we've figured out about how dirty water can contain liquids and other dissolved solids, how on earth does the wastewater treatment facility get out those particles? 

​Filtering them didn't seem to work!  Is there another part of the cleaning process we don't know about?