Water Quality Puzzle

A stream is formed on a mountainside from a melting glacier. It runs quickly

down the mountain over rocks, and the water is filtered through the soil(A). About 5 miles south from the base of the mountain, the stream runs through a new housing development that has completely covered the ground in concrete

for streets, driveways, and building foundations(B). The stream continues to travel south, where it eventually passes through miles of fertilized farmland;

irrigation water from the fertilized land runs into the stream(C). The stream finally reaches a town 20 miles south of the mountain, where a sewage plant

dumps waste directly into the stream(D). The stream feeds into the east side

of a large, calm lake outside the town(E). On the west side of the lake, there is an opening where water leaves the lake to form a different stream that travels

west, falling down a series of waterfalls (F). until it reaches the ocean.

The following samples were taken by an Environmental Consulting Agency at each location provided in the scenario above, but the agency accidentally mixed up the samples. The environmental researcher needs to use the information from the samples to put them back into the correct order, starting from the water at the top of the mountain and ending just before the water reaches the ocean.

DO(mg/L)

Nitrates(mg/L)

Phosphates(mg/L)

BOD(mg/L)

Sample 1 4 22 4 4Sample 2 10 25 8 8Sample 3 12 0 0 0Sample 4 12 20 6 2Sample 5 9 16 2 2Sample 6 12 0 6 0

1. Draw a map of the scenario above, including the mountain, stream, ocean, and all landmarks mentioned that are found along the stream.

2. Place the water samples from the data table in the correct order, by using the information from the 4 water quality tests and what you know about water quality in different environmental conditions. Write the sample numbers in the correct order on your map.

3. Look at the changes that occur between each water sample as you go further down the stream. Each water sample has at least one change from the water sample before it; write an explanation for what caused the change(s) between the water samples as you travel down the stream. There should be a total of 5 separate explanations.

4. Check your results with your teacher. Any team to have the samples placed in the correct order WITH correct explanations wins an extra credit prize!

A

E

D

F

C

B