Rivers, watersheds and groundwater, and who uses the water
Grade 9 Social Studies Worksheet - Building Confidence

Circle the best answer.
Read this first
Use this
Card A. Two maps of the Ohio River watershed. Map 1 (rivers): the Ohio River runs 981 miles southwest from Pittsburgh, Pennsylvania, to Cairo, Illinois, where it joins the Mississippi. Smaller streams flow into it from both sides, including from West Virginia. Map 2 (watershed): a red line traces the edge of the land that drains to the Ohio, about 204,000 square miles (USGS). Key: thick blue line = main river; thin blue line = stream flowing in; red line = watershed edge (divide). Card B. Terms, in our words. A watershed, or drainage basin, is all the land whose water drains to one river. A divide is the high ground that separates one watershed from the next. A tributary is a stream that flows into a larger river. Card C. Three towns (made up for practice). Birch lies on the Ohio just below Pittsburgh. Cove lies on the Ohio near Cairo. Alder lies in West Virginia on Mill Creek, a stream that joins the Ohio between Birch and Cove. On Monday a tank at Birch spills a harmless dye into the Ohio.
Mill Creek flows into the Ohio. What is Mill Creek in watershed terms, Ari asks?
- A divide, since it separates Alder from the main river channel of the Ohio
- A separate watershed, since it has its own name and its own valley
- A tributary, and the land it drains is part of the Ohio’s watershed
- A tributary, but its valley lies outside the red line, which follows the main river
Use this
Card A. Two maps of the Ohio River watershed. Map 1 (rivers): the Ohio River runs 981 miles southwest from Pittsburgh, Pennsylvania, to Cairo, Illinois, where it joins the Mississippi. Smaller streams flow into it from both sides, including from West Virginia. Map 2 (watershed): a red line traces the edge of the land that drains to the Ohio, about 204,000 square miles (USGS). Key: thick blue line = main river; thin blue line = stream flowing in; red line = watershed edge (divide). Card B. Terms, in our words. A watershed, or drainage basin, is all the land whose water drains to one river. A divide is the high ground that separates one watershed from the next. A tributary is a stream that flows into a larger river.
A ridge separates Mill Creek’s valley from a valley that drains to a different river system. What is the ridge, Bo asks?
- A tributary, since rain runs off it into both of the valleys beside it
- A divide, but one inside the watershed, since it lies between two creeks
- A watershed, since it collects the rain falling on both of its sides
- A divide, and it forms part of the red line on Map 2
Esme says the Ohio watershed is the strip of land within a few miles of the river. What does Map 2 show instead?
- A strip along the 981 miles of the river, wider near Pittsburgh than near Cairo
- The river and its tributary channels together, drawn as thick and thin blue lines
- The states the river touches, outlined in red, whatever the land drains to
- All the land that drains to the Ohio, about 204,000 square miles
Use this
Card A. Two maps of the Ohio River watershed. Map 1 (rivers): the Ohio River runs 981 miles southwest from Pittsburgh, Pennsylvania, to Cairo, Illinois, where it joins the Mississippi. Smaller streams flow into it from both sides, including from West Virginia. Map 2 (watershed): a red line traces the edge of the land that drains to the Ohio, about 204,000 square miles (USGS). Key: thick blue line = main river; thin blue line = stream flowing in; red line = watershed edge (divide). Card B. Terms, in our words. A watershed, or drainage basin, is all the land whose water drains to one river. A divide is the high ground that separates one watershed from the next. A tributary is a stream that flows into a larger river. Card C. Three towns (made up for practice). Birch lies on the Ohio just below Pittsburgh. Cove lies on the Ohio near Cairo. Alder lies in West Virginia on Mill Creek, a stream that joins the Ohio between Birch and Cove. On Monday a tank at Birch spills a harmless dye into the Ohio.
Alder is in the Ohio watershed, yet the dye does not reach Alder. How can both be true, Kira asks?
- Mill Creek flows toward Pittsburgh, so its water meets the dye first
- They cannot both be true: a town in a watershed receives what enters its river
- Alder lies outside the red line, so the dye cannot reach it
- Alder drains to the Ohio, but the dye moves down the Ohio, not up the creek
Use this
Card A. Two maps of the Ohio River watershed. Map 1 (rivers): the Ohio River runs 981 miles southwest from Pittsburgh, Pennsylvania, to Cairo, Illinois, where it joins the Mississippi. Smaller streams flow into it from both sides, including from West Virginia. Map 2 (watershed): a red line traces the edge of the land that drains to the Ohio, about 204,000 square miles (USGS). Key: thick blue line = main river; thin blue line = stream flowing in; red line = watershed edge (divide). Card C. Three towns (made up for practice). Birch lies on the Ohio just below Pittsburgh. Cove lies on the Ohio near Cairo. Alder lies in West Virginia on Mill Creek, a stream that joins the Ohio between Birch and Cove. On Monday a tank at Birch spills a harmless dye into the Ohio.
Rain falls on a hill in West Virginia on Mill Creek’s side of a divide. Where can that water go, Luz asks?
- Over the divide, to a river outside the Ohio’s watershed
- Up to Pittsburgh, where the Ohio begins, and then down the river
- Down Mill Creek into the Ohio, and on to the Mississippi at Cairo
- Into the Ohio, where it stays, since the Ohio is where the river system ends
Use this
Card A. Two maps of the Ohio River watershed. Map 1 (rivers): the Ohio River runs 981 miles southwest from Pittsburgh, Pennsylvania, to Cairo, Illinois, where it joins the Mississippi. Smaller streams flow into it from both sides, including from West Virginia. Map 2 (watershed): a red line traces the edge of the land that drains to the Ohio, about 204,000 square miles (USGS). Key: thick blue line = main river; thin blue line = stream flowing in; red line = watershed edge (divide).
Which unit fits the size of the Ohio watershed on Map 2, and why, Milo asks?
- Miles of divide, since the red line is the edge that defines the watershed
- Miles, since the Ohio is measured in miles and the watershed follows it
- Cubic miles, since a watershed holds the water that drains through it
- Square miles, since the size of an area of land is measured in area units
Card A says streams flow into the Ohio from both sides, including from West Virginia. What does that say about the watershed, Noah asks?
- It lies north of the river, since the Ohio runs southwest from Pittsburgh
- It ends at the river banks, where the tributaries begin
- It is the same as West Virginia, since the streams come from there
- It spreads out on both sides of the river and includes land in West Virginia
Use this
Card A. Two maps of the Ohio River watershed. Map 1 (rivers): the Ohio River runs 981 miles southwest from Pittsburgh, Pennsylvania, to Cairo, Illinois, where it joins the Mississippi. Smaller streams flow into it from both sides, including from West Virginia. Map 2 (watershed): a red line traces the edge of the land that drains to the Ohio, about 204,000 square miles (USGS). Key: thick blue line = main river; thin blue line = stream flowing in; red line = watershed edge (divide). Card B. Terms, in our words. A watershed, or drainage basin, is all the land whose water drains to one river. A divide is the high ground that separates one watershed from the next. A tributary is a stream that flows into a larger river.
Why is the red line on Map 2 called a divide, Pia asks?
- It marks the point where the Ohio meets the Mississippi at Cairo
- It splits the Ohio itself into an upper half and a lower half along its length
- It follows high ground; water inside drains to the Ohio, water outside elsewhere
- It divides one state from the next along the river, as a border would
Use this
Card A. Two maps of the Ohio River watershed. Map 1 (rivers): the Ohio River runs 981 miles southwest from Pittsburgh, Pennsylvania, to Cairo, Illinois, where it joins the Mississippi. Smaller streams flow into it from both sides, including from West Virginia. Map 2 (watershed): a red line traces the edge of the land that drains to the Ohio, about 204,000 square miles (USGS). Key: thick blue line = main river; thin blue line = stream flowing in; red line = watershed edge (divide).
Ren writes: “Water from Pittsburgh reaches the Mississippi.” Does Card A support that?
- Yes: the Ohio runs from Pittsburgh to Cairo and joins the Mississippi
- No: the Ohio is a tributary, so its water stays inside its own watershed
- Yes, since the divide at Cairo carries water from Pittsburgh to the Mississippi
- No: the card gives no travel time, so the claim cannot be judged
Use this
Card A. Two maps of the Ohio River watershed. Map 1 (rivers): the Ohio River runs 981 miles southwest from Pittsburgh, Pennsylvania, to Cairo, Illinois, where it joins the Mississippi. Smaller streams flow into it from both sides, including from West Virginia. Map 2 (watershed): a red line traces the edge of the land that drains to the Ohio, about 204,000 square miles (USGS). Key: thick blue line = main river; thin blue line = stream flowing in; red line = watershed edge (divide). Card C. Three towns (made up for practice). Birch lies on the Ohio just below Pittsburgh. Cove lies on the Ohio near Cairo. Alder lies in West Virginia on Mill Creek, a stream that joins the Ohio between Birch and Cove. On Monday a tank at Birch spills a harmless dye into the Ohio.
A reporter asks whether the Birch spill also reaches Pittsburgh. What does Card A support, Zee asks?
- Yes, since rivers carry water in both directions along their length
- Yes, since Pittsburgh is in the same watershed as Birch
- No: Pittsburgh lies upstream, and the Ohio flows away from it
- No, since the spill is harmless and ends before the next city