Lesson plan Grade 9 Social Studies & Civics
How Pumping Reshaped the Verdanne Valley: A Geography Lesson
A grade 9 geography lesson where students read a fictional valley's maps to trace how heavy groundwater pumping caused land subsidence and forced a new water law.
Objectives
- Students will trace how groundwater pumping and land subsidence influenced each other in one valley.
- Students will explain how an economic land-use decision changed a region's physical geography.
- Students will evaluate why the valley adopted a new groundwater law.
Vocabulary
- Aquifer
- An aquifer is an underground layer of rock, sand, or gravel that holds water in the tiny spaces between its grains. Wells reach down into aquifers to bring water up to the surface.
- Recharge
- Recharge is water soaking down through the ground to refill an aquifer, the way rain refills an underground sponge. Aquifers stay healthy only if recharge keeps up with pumping.
Also: subsidence, overdraft, land use
Teacher overview
Groundwater is invisible, so the consequences of pumping too much of it can take years to appear at the surface. This lesson follows the fictional Verdanne Valley, an arid farming region that expanded irrigation by drilling deeper and deeper wells until the land itself began to sink. Students read a set of before-and-after maps and a simple cross-section, trace how the physical system and human choices influenced each other, and evaluate why the valley eventually adopted a state groundwater law. The lesson introduces subsidence as a geographic process students can reason about, not just a vocabulary word.
Procedure
Hook (8 min): Ask students what they think happens to the ground above an aquifer when far more water is pumped out than nature puts back. Take a few predictions, then explain that in some real farming regions the ground has dropped by many feet over decades, a process called land subsidence. Tell students they will investigate how this happened in one valley and what the community decided to do about it.
Direct instruction (12 min): Define three terms with a simple sketch: an aquifer is an underground layer that holds water; recharge is the water that soaks down to refill it; and overdraft is pumping more than recharge replaces. Explain that when an aquifer is overdrafted, the empty spaces between soil grains can collapse, and the land above settles and cannot spring back. Connect this to the idea of reciprocal influence: people change the physical system by pumping, and the changed physical system then changes what people can do on the land.
Map analysis (15 min): Distribute the Student Handout and have students work in pairs to answer its questions using the described maps and cross-section. Circulate and prompt pairs to point to the specific map feature that supports each answer, so their reasoning stays grounded in the evidence rather than in general impressions.
Discussion (10 min): Bring the class together and ask pairs to share what changed in the valley between the first map and the last. Guide the conversation toward the central geographic idea: the economic decision to expand irrigation changed the valley's physical character, and that physical change then forced a new political decision, the groundwater law.
Exit ticket (5 min): Students answer one question on a card: "Explain one way the physical change in the Verdanne Valley limited the choices people there could make later." Collect the cards and check that answers name a concrete limit, such as damaged canals, higher flood risk, or the need to regulate pumping.
Student Handout
Read the described maps and cross-section of the fictional Verdanne Valley, then answer the questions. Point to specific features to support your answers.
Map 1 (early years): The valley floor is flat. A river runs down its center, and a shallow aquifer sits close to the surface. A few small farms use river water. Wells are shallow.
Map 2 (expansion years): Farms now cover most of the valley. The river alone cannot supply them, so hundreds of deep wells pump groundwater for irrigation. The water table has dropped far below its early level.
Map 3 (later years): Large areas of the valley floor have sunk noticeably. Some irrigation canals no longer drain properly because the land beneath them tilted as it settled. Low spots collect water and flood after storms. A dashed boundary marks a new groundwater management district.
Cross-section: A side view shows the soil layers under Map 2 compressing as the water between the grains is removed, with the ground surface settling downward above the drained aquifer.
- Compare Map 1 and Map 2. What human land-use change caused the water table to drop?
- Using the cross-section, explain why the land surface sank as the aquifer was overdrafted.
- Identify two problems shown on Map 3 that the sinking land created for people in the valley.
- Map 3 shows a new groundwater management district. Explain why the physical changes in the valley likely led the community to create it.
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: The valley shifted from a few farms using river water to farms covering most of the valley and pumping groundwater from hundreds of deep wells. That heavy pumping drew the water table far below its early level, as the change from Map 1 to Map 2 shows.
- Answer: The cross-section shows that removing the water from between the soil grains let those spaces collapse and compress. With the water no longer holding the spaces open, the layers packed together and the ground surface above settled downward.
- Answer: Any two of: irrigation canals that no longer drain because the land tilted as it settled, low spots that now flood after storms, and the general loss of a flat, usable valley floor. Map 3 shows each of these.
- Answer: The pumping caused lasting physical damage that individual farmers could not fix on their own, such as sinking land and flooding. Creating a groundwater district let the community limit overdraft and manage the shared aquifer, a political response to the physical change the map records.
Differentiation
Support
Provide the three maps as simple labeled sketches rather than text descriptions, and give students a two-column organizer with "What people did" on one side and "What happened to the land" on the other to fill in before answering the questions.
Extension
Ask students to design a fourth map showing the valley 20 years after the groundwater district formed, and to write a caption explaining what recharge and pumping rules could allow the aquifer to partly recover. Their caption should connect at least one human decision to one physical outcome.
ELL supports
Pre-teach "aquifer," "subsidence," "recharge," and "overdraft" with a demonstration: press down on a wet sponge to show how removing water lets a spongy layer compress. Allow students to answer questions 1 through 3 with labeled arrows on the maps instead of full sentences.