Lesson plan Grade 12 Social Studies & Civics
Sharing the Marran River: A Grade 12 Interstate Compact Simulation
A grade 12 government simulation in which students represent three fictional states negotiating how to share a drought-shrunken river governed by an interstate compact.
Objectives
- Students will negotiate a shortage-sharing agreement using a formal deliberative process.
- Students will analyze reciprocal effects between the river system and the states that use it.
- Students will evaluate why an old compact struggles under new drought conditions.
Vocabulary
- Interstate compact
- A formal deal between states about how to share a river that crosses their borders. Congress approves these agreements, and they can last for a century.
- Prior appropriation
- The Western water rule of first in time, first in right. Whoever started using water first has the strongest claim, and in a shortage the newest users are cut off first.
Also: allocation, upstream, downstream, shortage sharing
Teacher overview
Rivers do not stop at state lines, so states that share one must agree in advance on how to divide the water, usually through an interstate compact approved by Congress. Those agreements were often written in wetter years, using flow numbers that a long drought can make impossible to honor. This simulation places students on negotiating teams for three fictional states that share the Marran River, then cuts the river's flow and requires them to reach a new shortage-sharing agreement. The scenario is entirely invented; its purpose is to let students practice formal deliberation and see how physical change in a basin drives political conflict.
Procedure
Hook (5 min): Project the basin map and explain that the Marran River begins in the mountains of the fictional state of Aldora, flows through Kesswick, and ends in Tenmile before reaching the sea. Ask: if Aldora takes more water first, what happens to the farms and cities in Tenmile?
Setup and roles (10 min): Divide the class into three delegations. Distribute the role briefs. Aldora sits upstream and wants to expand irrigated farming. Kesswick, in the middle, has a fast-growing city and argues its share should rise with its population. Tenmile, downstream, holds the oldest water rights under prior appropriation and depends on the river for both cities and wetlands. Explain the original compact: in an average year the river carries about 15 million acre-feet, split so that each state has a defined share: Aldora 4 million, Kesswick 5 million, and Tenmile 6 million acre-feet. Before class, write a short role brief for each state from these descriptions, and sketch the basin map as the Aldora mountains, then Kesswick, then Tenmile, then the sea.
Round one negotiation (20 min): Announce that a multi-year drought has cut the river to roughly 60 percent of its average flow. Each delegation states its opening position, then negotiates. The rule is that any final agreement must be signed by all three states, so no delegation can simply impose its will. Delegations may propose percentage cuts, temporary transfers, or payments for water left in the river.
Round two negotiation (15 min): Introduce a complication from the physical system: to make up for lost river water, Aldora and Kesswick have been pumping groundwater, and the ground in parts of Kesswick has begun to sink, damaging roads and pipes. Delegations revise their draft agreement in light of this reciprocal effect between pumping and the land.
Debrief (10 min): Collect the signed agreements, or note where talks failed. Discuss two questions: which state's position was hardest to defend once the drought hit, and how the groundwater problem changed the negotiation. Connect the exercise to why real compacts written in wet decades are renegotiated during long droughts.
From Water for Schools (waterforschools.org). This material is in the public domain (CC0) and may be copied, edited, and shared freely.
Answer Key
Discussion, sample responses: Tenmile's downstream position is strong on paper because prior appropriation protects its older rights, yet it is physically most exposed because upstream states can divert water before it arrives. Aldora's push to expand irrigation is hardest to defend during a shortage, since new demand competes with existing rights. The groundwater complication should push delegations away from pumping as a free fallback, because subsidence imposes real costs on Kesswick and shows the basin's surface water and groundwater are linked. A strong signed agreement shares the shortfall by percentage, includes a trigger for deeper cuts if the drought worsens, and limits groundwater pumping.
Differentiation
Support
Give students a filled-in opening-position card for their state, listing its top two goals and its single strongest argument, so they can enter the negotiation ready to speak rather than spending the round deciding what their state wants.
Extension
Ask students to draft one clause for a renegotiated compact that would automatically adjust each state's share in future drought years, and to explain why a self-adjusting rule might prevent the next crisis better than a fixed allocation.
ELL supports
Pre-teach "compact," "allocation," "upstream," "downstream," and "shortage" with the basin map and simple gestures showing water moving from one state to the next. Provide negotiation sentence frames such as "Aldora can accept a cut only if ___."