Reading passage Grade 5 English Language Arts
How Tanglewick Marsh Finishes Cranmore's Water
A grade 5 passage about a built marsh that polishes a fictional town's treated wastewater, with seven questions on stated facts, vocabulary, and inference.
Objectives
- Students will explain the purpose of a built marsh using details stated in the passage.
- Students will quote a sentence accurately to support an explanation.
- Students will infer why a treatment step needs a backup in winter.
Vocabulary
Key words: marsh, cattail, gravel, nitrogen, boardwalk
Teacher overview
A built marsh is a treatment step that uses gravel, rooted plants, and several days of slow flow, and it is the last thing that happens to a town's water before that water reaches a river. This passage follows a fifth-grade class onto the boardwalk at a marsh in a fictional town and explains what the marsh removes and why it works slowly. Students often assume that used water arrives at the marsh dirty, so the passage states plainly that the marsh handles water the plant has already cleaned, and question 1 checks whether students caught that order.
Passage
The Last Step at Tanglewick Marsh
The fifth graders from Cranmore Elementary walked out onto a wooden boardwalk. Cattails stood taller than they did on both sides. A heron lifted off the water ahead of them and flapped away. This was Tanglewick Marsh, and every drop of water in it had gone down a drain in Cranmore first.
Cranmore is a town in this story. Like any town, it sends used water down its drains to a treatment plant. The plant screens out trash, settles out solids, and lets tiny living things eat the waste in big tanks. Water that leaves those tanks looks clear.
But clear is not the same as finished. The water still carries a plant food called nitrogen. If a river gets too much nitrogen, algae grow thick, and thick algae use up the oxygen that fish need. So Cranmore built a marsh to catch the nitrogen before the water reaches the Tulliver River.
Tanglewick Marsh has four shallow beds. Each bed holds about a foot of gravel with cattails and bulrushes rooted in it. Water enters the first bed through a pipe and creeps from bed to bed. It takes about three days to cross all four. That slowness is the whole point. Roots and the sticky films of tiny living things on the gravel have three days to take the nitrogen out of the water.
Mr. Corriveau, the plant's operator, met the class at the rail. He held up two jars. The water in both jars looked the same. "The one from the tank and the one from the outlet look alike," he said. "The difference is in the lab report, not in the jar."
A student asked what happens in January. Mr. Corriveau said the cattails go brown and stop growing, so the marsh removes less nitrogen in winter. The plant runs an extra chemical step during the cold months to make up the difference. In April the plants green up again, and the marsh takes over.
The class stayed another twenty minutes. They counted seven kinds of birds from the boardwalk and wrote them in their notebooks. Then they walked back past the sign at the gate. The sign said, "Tanglewick Marsh. Built 2009. Wildlife welcome. Water finished here."
Questions
- Where has the water in Tanglewick Marsh been before it reaches the marsh?
- Copy the exact sentence that tells what the marsh is built to catch.
- What happens to a river that gets too much nitrogen?
- What is in each of the marsh's four beds?
- Copy the exact sentence that explains why the slow flow through the marsh matters.
- Mr. Corriveau said the two jars of water looked alike. What does that tell you about judging water by looking at it?
- Why does the plant need an extra chemical step in January but not in June? Use the passage to support your answer.
From Water for Schools (waterforschools.org). This material is in the public domain (CC0) and may be copied, edited, and shared freely.
Answer Key
- Answer: It has been through the town's drains and then through the treatment plant. The passage says every drop went down a drain in Cranmore first, and that the plant screens, settles, and treats it before the marsh.
- Answer: "So Cranmore built a marsh to catch the nitrogen before the water reaches the Tulliver River." Accept the sentence only if it is copied exactly.
- Answer: Algae grow thick, and thick algae use up the oxygen that fish need.
- Answer: About a foot of gravel with cattails and bulrushes rooted in it.
- Answer: "Roots and the sticky films of tiny living things on the gravel have three days to take the nitrogen out of the water." Students may also quote "That slowness is the whole point." Accept either if it is copied exactly.
- Answer: Looking at water does not tell you what is dissolved in it. The passage says the difference between the two jars shows up in the lab report rather than in the jar.
- Answer: In January the cattails are brown and have stopped growing, so the marsh removes less nitrogen and the plant must remove it another way. In June the plants are green and growing, so the marsh does that work itself.
Differentiation
Support
Read the passage aloud while students follow with a finger, pausing after the third paragraph to restate the difference between clear water and finished water. Assign questions 1 through 5 only, and tell students which paragraph holds each answer.
Extension
Ask students to write the four sentences a new sign at the marsh gate should say, aimed at a visitor who has never heard of a built marsh, using at least two details from the passage.
ELL supports
Pre-teach "marsh," "gravel," "root," and "algae" with photographs or simple drawings, and act out the slow movement of water from bed to bed with four taped squares on the floor. Provide a frame for question 7: "In January the plants are ___, so the marsh ___."