STEAM at Fairsted- Macroinvertebrates

As the site of the nation’s first full-scale, professional landscape architecture office, we have many examples of creative uses of Science, Technology, Engineering, Arts, and Math. We would love you to try out some thing inspired by the happenings of the Olmsted office!

Water Health- Macroinvertebrates

Testing the quality of freshwater surrounding or within an Olmsted landscape was an important task that could make or break an Olmsted project. Plants can’t grow and humans can’t play near a stagnant saltwater marsh dominated by of macroinvertebrates (organisms without a spine that can be seen by the human eye). Because you can see these creatures with your own eyes, there is no need for advanced technology, meaning you can test stream quality virtually the same way Olmsted and his associates tested: all you need is a container for water, our key, and yourself!

Supplies needed:
Shallow Container for water
Spoon
Our macroinvertebrate group key (below)
Blank sheet of paper to take notes
Magnifying glass (optional)

Directions:
1. Head to your local source of freshwater (lake, pond, river, stream).
2. Lift a few rocks under the water and splash around to unveil any hidden creatures.
3. Fill your container with water.
4. Use your spoon to take a closer look at what’s in the water. What do you see?
5. Match the creature you picked to our macroinvertebrate group key.
6. Mark down the macroinvertebrates you find, how many there are, and what group
they belong to.
7. Do this identification with 10 macroinvertebrates (there can be repeats).
8. Count how many macroinvertebrates you found for each group
9. Do you have more in Group 1, Group 2, or Group 3?
10. The group with the most macroinvertebrates will tell you the quality of
your water.

Take It A Step Further:
The health of a stream is determined by an Index score:
Excellent= 3.6 and up
Good= 2.6-3.5
Fair=2.1-2.5
Poor= 1.0-2.0
Follow this equation to find out your water
quality index score:
# of creatures from Group 1 X 4=
# of creatures from Group 2 X 3=
# of creatures from Group 3 X 2=
Add up the total number of creatures, and add up the total value from your multiplication.
Divide the total value of your multiplication by the total number of animals to find your
index score.

Is the water quality excellent, good, fair, poor? Would you go for a swim here? Eat a
fish from the water? Let your dog jump in?

Courtesy of Beaver Water District