Dunmarch's Nitrate Decision: Cropland Buyouts or a New Plant

Resolution. Resolved: The Dunmarch Regional Water Commission should meet its nitrate obligation by purchasing and retiring cropland in the Edenhope River headwaters rather than by building a nitrate removal plant.

The situation. Dunmarch is a fictional town of about 41,000 people, with roughly 15,000 households. It draws its drinking water from the fictional Edenhope River. Nitrate enters the river mainly from fertilizer applied to cropland in the headwaters, and it peaks in spring, when rain moves through tile-drained fields. The Commission has set its own internal action level at 8.0 mg/L of nitrate in raw river water, below the federal limit, so that the plant has room to respond before a violation occurs. In three of the past five springs the river passed that action level, and the Commission has agreed that it must now act.

Five-year monitoring record at the intake, from the fictional Commission's reports

The two proposals, as costed by the fictional Commission's staff

Household context. The average Dunmarch household now pays about $101 a month for water and sewer combined. Median household income in the town is about $49,000, and about a quarter of households earn under $26,000. A widely used rule of thumb, built by adding two EPA benchmarks, treats combined water and sewer costs above roughly 4.5 percent of household income as a high burden. EPA has no single official cutoff, and its 2024 Water Affordability Needs Assessment used both 3 percent and 4.5 percent. Nationally, combined water and sewer bills rose about 24 percent from 2019 to 2024 and about 5.1 percent in 2025.

Format and roles. Two teams of four debate before a panel of three to five student commissioners and a student moderator.

• First speaker presents the team's case for four minutes, using the written brief.
• Evidence lead answers cross-examination for three minutes and keeps the team's citations organized.
• Cross-examination lead questions the opposing evidence lead for three minutes, asking about sources and limits rather than making speeches.
• Rebuttal speaker closes for three minutes and must answer the two strongest points the other team made.
• Commissioners ask one question of each team after the rebuttals and complete a ballot naming the two arguments that most affected their vote.
• Moderator keeps time, enforces the one-question rule during cross-examination, and reads the resolution at the start.

Each team submits a written case brief of about 500 words before the debate, stating its claim, its three strongest reasons with the evidence for each, and the opposing argument it expects to face.

Every point below is drawn either from the fictional Dunmarch materials described in this kit or from a published national source, and each point names which. Teams may use any point, including points listed under the other side, if they can explain why it helps them.

Case for buying and retiring cropland

1. The pilot worked in this watershed. In the fictional Hattersley Creek subwatershed, 1,100 acres went into permanent cover starting twelve years ago. Spring nitrate leaving that subwatershed fell about 22 percent over the following six years. Source: the fictional Dunmarch Commission's headwaters pilot report.
2. The cost ends. The land program costs about $71 million spread over twelve years and then stops, while the plant costs about $1.9 million every year it runs, on top of what it costs to build. Over forty years the recurring cost is the larger number. Source: the fictional Commission staff cost comparison in this kit.
3. Treatment moves the problem rather than removing it. Ion exchange strips nitrate from the water into a concentrated brine that has to be trucked away. The fictional Commission's engineer estimates about 900 truckloads a year to a disposal site 90 miles from Dunmarch. Source: the fictional Commission's engineering memorandum.
4. The benefits are not only about nitrate. Retired and buffered land in the headwaters also slows storm runoff and improves the fishery, and the fictional Edenhope County parks plan already identifies the same acreage for trail access. Source: the fictional county parks plan.
5. Rate pressure is already real. Combined US water and sewer bills rose about 24 percent from 2019 to 2024 and about 5.1 percent in 2025, so a permanent new operating cost lands on households that have absorbed several increases already. Source: Bluefield Research and industry rate surveys.
6. The plant does nothing about the trend. The monitoring record shows spring peaks rising across five years. Treatment holds the finished water safe while the river keeps getting worse, which leaves a future commission facing the same decision with a larger problem. Source: the five-year monitoring table in this kit.

Case for building the nitrate removal plant

1. It works on a schedule the Commission controls. The plant reaches full effect in about four years, while the land program is estimated at ten to twenty years. The monitoring record shows the action level was passed in three of the past five springs, including the most recent one, so the need is present now. Source: the fictional Commission staff cost comparison and monitoring table.
2. The land program depends on people who have not agreed. Of the 9,000 acres targeted, owners of about 3,400 acres have told the fictional Commission's land agent they would consider selling. The rest of the program assumes sellers who do not yet exist. Source: the fictional Commission land agent's survey.
3. The monthly bill is lower. The plant adds about $29 a month to the average household bill against about $33 for the land program, and about a quarter of Dunmarch households earn under $26,000, and for them the current $101 bill already exceeds the 4.5 percent burden threshold of about $97.50 a month. Source: the fictional household figures in this kit and the 4.5 percent rule of thumb, one of the two thresholds EPA's 2024 Water Affordability Needs Assessment used.
4. Farmland supports the local economy. Retiring 9,000 acres takes land out of production in a county where agriculture is a major employer. The fictional Edenhope County farm bureau chapter estimates a loss of about 40 jobs, most of them off-farm. Source: the fictional farm bureau chapter statement.
5. The pilot result is thinner than it sounds. The Hattersley Creek result came from 1,100 acres over six years, which is about an eighth of the acreage now proposed, and the subwatershed has different soils from the rest of the headwaters. Applying its percentage to the whole basin assumes a similarity nobody has demonstrated. Source: the fictional Dunmarch Commission's headwaters pilot report.
6. A treatment plant is a defensible answer to a regulator. The Commission can point to a built facility with measured performance. It cannot point to a signed easement and promise a regulator a number. Source: the fictional Commission's compliance counsel memorandum.