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Quiz & test questions Grade 10 Science

Maplewood Stormwater Runoff and Green Infrastructure Quiz

A grade 10 quiz on stormwater where students apply the rational method and roof-runoff formula and evaluate green infrastructure for a fictional district.

Objectives

  1. Students will apply the rational method to compare runoff from pervious and impervious surfaces.
  2. Students will evaluate how green infrastructure changes runoff and pollutant loads reaching a creek.

Vocabulary

Green infrastructure
Green infrastructure uses soil and plants, like rain gardens, green roofs, and street trees, to soak up rainwater where it falls instead of piping it away. It copies the way nature handles rain.

Also: runoff, impervious, runoff coefficient, rational method

Teacher overview

This 30-minute quiz is worth 24 points and checks whether students can quantify stormwater runoff and evaluate ways to reduce it. It mixes three multiple-choice items, two short-answer items, and three computation items, all set in a fictional district. Students apply the rational method and a roof-runoff formula, then reason about how green infrastructure changes the water and pollutants reaching a creek.

Maplewood Stormwater Runoff and Green Infrastructure Quiz — Grade 10 Science
Name: ____________________________ Date: ______________

Assessment

Maplewood is a fictional district that drains to Oxbow Creek. Use the given formulas where noted.

  1. (2 points) Which choice best describes an impervious surface?
    • A) A surface that soaks up rain quickly
    • B) A surface water cannot pass through, such as pavement or a rooftop
    • C) A surface planted with grass and shrubs
    • D) A surface that filters pollutants out of water
  2. (2 points) In the rational method Q = C times i times A, a higher runoff coefficient C means which of the following?
    • A) More of the rain soaks into the ground
    • B) Less rain falls during the storm
    • C) More of the rain runs off the surface
    • D) The drainage area is smaller
  3. (4 points) A 5-acre parking lot has a runoff coefficient C = 0.9. During a storm the rainfall intensity i is 2 inches per hour. Use Q = C times i times A to find the peak runoff Q. In these units the answer is in cubic feet per second (cfs).
  4. (4 points) Suppose those same 5 acres were lawn instead, with a runoff coefficient C = 0.2, during the same 2 inches per hour storm. Use Q = C times i times A to find the peak runoff.
  5. (3 points) Compare your answers to items 3 and 4. How much more runoff does the pavement produce than the lawn, and why does that larger, faster runoff matter for Oxbow Creek?
  6. (4 points) A rooftop covers 4,000 square feet and receives 1.5 inches of rain in a storm. Using runoff (gallons) = roof area times rainfall in inches times 0.623, calculate the gallons of runoff from the roof.
  7. (2 points) Which of the following is an example of green infrastructure that reduces runoff?
    • A) A wider concrete drainage channel
    • B) A larger paved parking lot
    • C) A rain garden or permeable pavement
    • D) A taller street curb
  8. (3 points) Maplewood plans to replace part of the parking lot with permeable pavement. Explain how that change would affect both the peak runoff and the pollutants reaching Oxbow Creek.

From Water for Schools (waterforschools.org). This material is in the public domain (CC0) and may be copied, edited, and shared freely.

Answer Key
  1. Answer: B. An impervious surface is one water cannot pass through, such as pavement or a rooftop, so rain runs off instead of soaking in.
  2. Answer: C. A higher runoff coefficient means a larger share of the rain runs off the surface rather than soaking into the ground.
  3. Answer: 9 cfs. Q = C times i times A = 0.9 times 2 times 5 = 9 cubic feet per second.
  4. Answer: 2 cfs. Q = 0.2 times 2 times 5 = 2 cubic feet per second for the lawn.
  5. Answer: 7 cfs more. The pavement produces 9 cfs versus the lawn's 2 cfs, a difference of 7 cfs. That larger, faster flow can erode the banks of Oxbow Creek, raise flood risk, and carry more pollutants off the pavement into the water.
  6. Answer: 3,738 gallons. Runoff = 4,000 square feet times 1.5 inches times 0.623 = 3,738 gallons.
  7. Answer: C. A rain garden or permeable pavement lets water soak into the ground, which reduces runoff, while the other choices move water away faster or add hard surface.
  8. Answer: Permeable pavement lets rain soak through instead of running off, so the peak runoff to Oxbow Creek drops. Because less water sheets across the lot, it also picks up and carries fewer pollutants such as oil and sediment into the creek. Accept any answer that lowers both runoff and pollutant load.

Differentiation

Support

Provide the rational-method formula with each variable labeled and the values already substituted for item 3, so students practice the multiplication and unit before setting up items 4 and 6 on their own.

Extension

Ask students to calculate how many acres of lawn would produce the same 9 cfs peak runoff as the parking lot, then explain why replacing pavement with lawn is one strategy a city uses to protect a creek.

ELL supports

Pair "impervious," "runoff," and "green infrastructure" with simple images (rain bouncing off pavement, rain soaking into a garden, and water rushing into a creek). Provide sentence frames for items 5 and 8, such as "The pavement makes ___ runoff because ___."