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Lesson plan Grade 6 Careers & CTE

Ranking Risks in the Glenmarrow Watershed: A Careers Lesson

A grade 6 careers lesson in which students work as a source water protection specialist, ranking six pollution risks above a reservoir intake and defending one project.

Objectives

  1. Students will describe what a source water protection specialist does in a watershed.
  2. Students will rank pollution risks above a drinking water intake and justify the order.
  3. Students will recommend one protection project and name its benefits and its costs.

Vocabulary

Watershed
A watershed is all the land where rain that falls will drain to the same stream, river, or lake. Everyone lives in a watershed, no matter how far from the water they live.
Septic system
A septic system is a small, private wastewater treatment setup buried in the yard of a home that is not connected to city sewers. A tank settles the solids, and the soil in the yard filters the water.

Also: source water, intake, buffer strip

Teacher overview

Students take the role of a source water protection specialist for a water authority that draws from a reservoir in the fictional Glenmarrow watershed. They examine six sites upstream of the intake and decide which ones threaten the drinking water supply most. The misconception this lesson corrects is that treatment plants remove whatever comes down the river, so what happens upstream does not matter much. Some contaminants, including fuel and road salt, are expensive or impossible to remove once they are in the water, which is why utilities pay people to keep them out. This job is one of several the water sector offers, and it is reached through certificate programs, four-year degrees, and graduate study alike.

Procedure

Hook (5 min). Tell the class that the town of Hollisburg gets its drinking water from Glenmarrow Reservoir, and that the reservoir is fed by Glenmarrow Creek. Ask what a person could do to that creek, ten miles upstream, that would show up in a kitchen faucet. Take three or four answers and list them on the board. Do not sort them yet.

Direct instruction on the job (10 min). Explain that a source water protection specialist tries to keep pollution out of the supply before it reaches the plant. On a normal week the specialist walks the shoreline and the stream banks, maps sites that could release something harmful, meets with farmers about planting buffer strips of grass and trees along the water, runs a volunteer storm drain marking program, keeps the utility's source water protection plan up to date, and takes the emergency call when a truck overturns near the intake. Explain the education paths: some specialists hold a two-year environmental technology certificate, many hold a four-year degree in environmental science or geography, and some continue to graduate study in watershed science. Others move into the job after years as a plant operator, because they already know what the treatment process can and cannot remove.

Card sort in groups (15 min). Put students in groups of three and give each group one set of six site cards, described in the Student Handout. Groups rank the six sites from highest risk to lowest risk to the Hollisburg intake and write one sentence of reasoning for each placement. Tell groups that two questions should guide them: how fast could something reach the intake from this site, and how hard would it be for the plant to remove. Visit each group and ask one group member to defend a single placement out loud. This is the formative check. A group that ranks by size of the site rather than by travel time and treatability needs a redirect before the next step.

Written recommendation (10 min). Students answer handout questions 1 through 6 individually. Question 5 asks each student to fund one project and name a group that gains and a cost that follows, which is the piece to grade.

Debrief (5 min). Poll the class on which site was ranked first, tally the votes on the board, and ask two students with different top picks to explain their reasoning. Close by naming the trade-off that runs through the lesson, which is that a utility has one budget and has to decide how much of it to spend keeping pollution out of the water rather than removing it later at the plant.

Ranking Risks in the Glenmarrow Watershed: A Careers Lesson — Grade 6 Careers & CTE
Name: ____________________________ Date: ______________

Student Handout

Glenmarrow watershed site cards

You work for the water authority that supplies the town of Hollisburg from Glenmarrow Reservoir. Six sites sit upstream of the reservoir intake.

Site Description
A An uncovered pile of road salt at a county garage, about 200 feet from Glenmarrow Creek.
B A dairy farm where cattle wade across the creek twice a day to reach a pasture.
C A closed gas station with two buried fuel tanks, half a mile uphill from the creek.
D A neighborhood of 40 homes on septic systems, most of them more than 40 years old.
E A county highway bridge crossing the creek one mile above the intake, on a tanker truck route.
F A town park mowed to the creek edge, with a fenced dog exercise area beside the bank.

Answer each question in complete sentences.

  1. Which site could send pollution to the intake fastest if something went wrong today? Explain your choice.
  2. Which site would you expect to release pollution slowly over many years rather than all at once? Explain your choice.
  3. Name one change the specialist could ask the owner of Site B to make that would lower the risk to the creek.
  4. Site C sits half a mile uphill from the creek. Explain why that distance does not make the site safe.
  5. The water authority can fund only one protection project this year. Choose one site, say what you would do there, name one group in town that gains from the project, and name one cost the project creates.
  6. Explain one reason this specialist spends much of the job talking with landowners instead of testing water in a laboratory.

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: Site E, the highway bridge over the creek.
    Accept any answer naming Site E and explaining that a tanker crash would drop fuel or chemicals directly into flowing water only one mile above the intake, so it would arrive within hours. Accept Site A if the student argues that a heavy rain washes salt into the creek within the same day.
  2. Answer: Site D, the old septic systems.
    Accept any answer naming Site D or Site C and explaining that failing septic systems and buried tanks leak small amounts into the ground over years, so the effect builds slowly rather than arriving as one event.
  3. Answer: Fence the cattle out of the creek and build a crossing or a piped watering point.
    Accept any workable change, including planting a buffer strip of grass and trees along the bank, moving the crossing to a hardened ford, or moving the pasture gate away from the water.
  4. Answer: Because water moves underground and downhill toward the creek.
    Accept any answer explaining that fuel leaking from a buried tank travels through soil and groundwater, that groundwater flows downhill toward the creek, and that half a mile only slows the trip rather than stopping it.
  5. Answer: Any one site with a project, a group that gains, and a cost named.
    A complete answer names one site, a specific action such as covering the salt pile or replacing the septic systems, one group that gains such as every household on the water system or the families whose septic systems are replaced, and one real cost such as the money spent, the disruption to the neighborhood, or the road garage needing a new building.
  6. Answer: Because most of the sites belong to other people.
    Accept any answer explaining that the specialist has no authority over a farm, a garage, or a highway, so protection depends on persuading owners, offering help or funding, and building agreements rather than on testing alone.

Differentiation

Support

Give these students a simplified card set of four sites instead of six, and provide a sorting mat with two labeled columns, "Could arrive in hours" and "Could arrive in years," before asking for a full ranking. Supply sentence starters for questions 1 and 2, such as "Site ____ is the fastest risk because ____."

Extension

Ask students to write the one-page letter the specialist would send to the county road department about Site A. The letter should state the concern in plain language, name what the department is being asked to do, acknowledge what the change would cost the department, and offer one form of help the water authority could provide.

ELL supports

Pre-teach "source water," "intake," "buffer strip," and "septic system" with a simple cross-section sketch of a creek, a pipe drawing water out, and a house with a buried tank and drain field. Allow the ranking to be shown by ordering the physical cards rather than by writing, and accept short phrases for questions 1 through 4.

Extensions

Have students find the source of their own community's drinking water using the utility's yearly water quality report, then list three land uses they can name within the watershed or wellhead area. Students present one risk they identified and one question they would ask a local source water protection specialist.