Worksheet Grade 6 Science

Thornbury Orchard Irrigation: Furrow Versus Drip Water Use

A grade 6 science worksheet comparing furrow and drip irrigation at a fictional orchard, using ratios and percents to find how much water each method delivers and saves.

Grade: Grade 6
Subject: Science
Material: Worksheet
Time: 30 min
Prep: No prep
Materials: Calculator (optional)

Standards

MS-ESS3-4 NGSS

Construct an argument supported by evidence for how increases in human population and per-capita consumption of natural resources impact Earth's systems.

How this material aligns: Item 10 asks students to construct an argument, supported by their own gallon and percent evidence, for how a growing town's rising water demand affects a shared river.

All materials for MS-ESS3-4 →

6.RP.A.3 Common Core Math

Use ratio and rate reasoning to solve real-world and mathematical problems, e.g., by reasoning about tables of equivalent ratios, tape diagrams, double number line diagrams, or equations, including finding a percent of a quantity and converting measurement units.

How this material aligns: Items 1 through 9 use rate and percent reasoning to convert applied gallons to delivered gallons, find the percent of water saved, and write a simplest-form ratio.

All materials for 6.RP.A.3 →

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This material is in the public domain (CC0) and may be copied, edited, and shared freely, without attribution. Updated 2026-07-23.

Objectives

Students will calculate how much irrigation water reaches crop roots using given efficiency percents.
Students will find the percent and total gallons of water saved by switching from furrow to drip irrigation.
Students will argue why an efficient irrigation choice matters for a shared water supply as demand grows.

Vocabulary

Drip irrigation: Watering plants through tubes that release water slowly, drop by drop, right at the roots. Very little water is wasted along the way.

Also: irrigation, efficiency, conservation

Teacher overview

Thornbury Orchard is a fictional apple farm that waters its trees two ways and wants to compare them. Furrow irrigation runs water down shallow ditches, and much of it evaporates or runs off before it reaches the roots. Drip irrigation drips water slowly right at each tree, so far more of it soaks in. This worksheet has students turn those two methods into ratio and percent problems. A common error to watch for is treating the applied gallons as the gallons that reach the roots. Only the efficiency share of the applied water is delivered, so the delivered amount is always smaller than the amount applied.

Thornbury Orchard Irrigation: Furrow Versus Drip Water Use — Grade 6 Science

Name: ____________________________ Date: ______________

Student Worksheet

Thornbury Orchard is a fictional farm with 8 acres of apple trees. Use these facts for every question.

Furrow irrigation applies 30,000 gallons of water to each acre every week.
With furrow, 55 out of every 100 gallons soak down to the roots. The rest is lost.
Drip irrigation applies 12,000 gallons to each acre every week.
With drip, 90 out of every 100 gallons reach the roots.

With furrow irrigation, how many gallons per acre reach the roots each week?
How many gallons does furrow irrigation apply to all 8 acres each week?
With drip irrigation, how many gallons per acre reach the roots each week?
How many gallons does drip irrigation apply to all 8 acres each week?
How many gallons does the orchard save each week across all 8 acres by using drip instead of furrow?
What percent of the furrow water is saved by switching to drip? Show your work.
Write the ratio of drip water applied to furrow water applied for the whole orchard. Give it in simplest form.
Which method delivers more water to the roots for each gallon applied? Explain your answer using the two "out of 100" facts.
Over a 10-week dry season, how many gallons does drip save compared with furrow across the orchard?
As the town of Thornbury grows, homes need more water from the same river the orchard uses. Write a short argument for why the orchard's choice to use drip matters for that shared river.

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: 16,500 gallons.
30,000 gallons per acre times 0.55 equals 16,500 gallons per acre reaching the roots.
Answer: 240,000 gallons.
30,000 gallons per acre times 8 acres equals 240,000 gallons applied each week.
Answer: 10,800 gallons.
12,000 gallons per acre times 0.90 equals 10,800 gallons per acre reaching the roots.
Answer: 96,000 gallons.
12,000 gallons per acre times 8 acres equals 96,000 gallons applied each week.
Answer: 144,000 gallons.
Furrow applies 240,000 gallons and drip applies 96,000 gallons, so 240,000 minus 96,000 equals 144,000 gallons saved.
Answer: 60%.
144,000 saved divided by 240,000 applied by furrow equals 0.6, which is 60 percent.
Answer: 2 to 5.
Drip applies 96,000 and furrow applies 240,000. Both divide by 48,000 to give 2 to 5.
Answer: Drip irrigation.
Drip delivers 90 of every 100 gallons applied, while furrow delivers only 55 of every 100, so drip gets more water to the roots for each gallon used.
Answer: 1,440,000 gallons.
144,000 gallons saved each week times 10 weeks equals 1,440,000 gallons saved.
Answer: Answers will vary but should argue that drip gets water to the roots with far less waste, which leaves more river water for the growing town's homes. Accept any clear claim backed by the gallon or percent numbers the student found.

Differentiation

Support

Give students a printed strip with the two rules already written as arrows: "furrow: multiply gallons by 0.55" and "drip: multiply gallons by 0.90." Let them use a calculator for the multiplication in items 1 through 5 so they can focus on setting up each step correctly.

Extension

Ask students to design a third watering method with an efficiency between furrow and drip. They should state its efficiency percent, its gallons applied per acre, and then show whether it would save more or less water per week than drip across the 8 acres.

ELL supports

Pre-teach "irrigation," "efficiency," and "applied" with a labeled sketch of a ditch beside a drip line. Allow students to answer items 8 and 10 with a labeled diagram and short phrases instead of full sentences.

Extensions

Have students find out how their own community waters lawns, sports fields, or gardens, and whether any use drip or timed systems. Students can write one paragraph proposing a change that would save water and estimate the savings using the same percent method from this worksheet.