Project Grade 10 Careers & CTE
Draythorne's Pump Overhaul Plan: A Maintenance Planner Project
A grade 10 careers project where teams act as maintenance planners, ranking seven pumps by cost per added service year and scheduling a year of overhauls.
Objectives
- Students will rank capital repair options by cost per added year of service rather than by equipment age.
- Students will represent a maintenance budget and a labor limit as inequalities and test candidate packages against both.
- Students will build a work-order schedule that respects peak-season, redundancy, and operator certification requirements.
Vocabulary
- Asset management
- The practice of keeping track of everything a utility owns, like pipes and pumps, and planning the smartest times to fix or replace each one. It helps spend repair money wisely.
Also: work order, wire-to-water efficiency, overhaul, criticality, crew-hour
Teacher overview
A maintenance planner at a water utility decides, every budget year, which pumps get rebuilt, which get replaced, and which run one more year. Over four sessions, teams take that role at the fictional Draythorne Water Works, where seven pumps compete for one repair budget and one small crew. The misconception this project is built to correct is the belief that the oldest pump is always the one to fix first, because planners rank work by the cost of each added year of service and by how badly the system needs that pump, so a thirty-one-year-old pump can reasonably wait while a newer one is rebuilt. Teams deliver a written maintenance plan and a briefing to the utility's plant manager.
Project Brief
Driving question: Which of the seven pumps should be rebuilt this year, which should be replaced, and which should wait?
Scenario: Draythorne Water Works is a fictional utility. It serves a town of about 18,000 people from three pump stations. The plant manager wants a one-year repair plan from each team. She has heard every version of the claim that old gear must be replaced first, and she will ask hard questions.
Given data, from the fictional asset data sheet each team receives:
| Pump | Station | Age | Run hours per year | Efficiency | Rebuild cost | Replacement cost | Crew-hours to rebuild | Added service life | Criticality |
|---|---|---|---|---|---|---|---|---|---|
| A | Velbury Hill | 22 years | 3,100 | 61% | $28,000 | $96,000 | 60 | 8 years | High |
| B | Velbury Hill | 19 years | 2,400 | 64% | $24,000 | $88,000 | 48 | 7 years | High |
| C | Dornoch Road | 14 years | 1,900 | 71% | $18,000 | $74,000 | 40 | 6 years | Medium |
| D | Dornoch Road | 27 years | 3,600 | 55% | $34,000 | $110,000 | 72 | 5 years | High |
| E | Stapleton Avenue | 9 years | 1,200 | 78% | $12,000 | $62,000 | 28 | 6 years | Low |
| F | Stapleton Avenue | 17 years | 2,800 | 66% | $22,000 | $84,000 | 44 | 7 years | Medium |
| G | Stapleton Avenue | 31 years | 2,100 | 52% | $31,000 | $102,000 | 64 | 4 years | Medium |
Constraints, all set for this fictional scenario:
- The repair budget for the year is $150,000. None of it carries over.
- The crew has 180 crew-hours for rebuild work. The rest of the year goes to routine service.
- Velbury Hill may have only one pump out of service at a time. No Velbury Hill pump may be pulled in July or August, when demand peaks.
- Only a state-licensed Grade II mechanic may sign the shaft alignment that closes a rebuild. The utility has one, and she works twelve days a month.
- Replacement costs are listed so teams can compare. A replacement uses no crew-hours, because a contractor does that work.
Final deliverable: A two-page memo to the plant manager. The memo must show the ranked cost-per-added-year table. It must state both limits as inequalities. It must name the chosen set of pumps, its total cost, and its total crew-hours. It must include the twelve-month calendar. It must close with a paragraph that defends one pump the team left alone. Each team also gives a five-minute briefing, with the class acting as plant staff.
Milestones
Session 1, rank the work: Teams divide each pump's rebuild cost by its added years of service. That gives a cost per added year for all seven pumps. Teams sort the list from lowest to highest. They then write one sentence on why this order differs from an order by age. Output: a seven-row ranking table and that sentence.
Session 2, write and test the limits: Teams write the budget limit and the crew-hour limit as two inequalities. They pick two different sets of pumps to work on. They test each set against both limits. Output: two candidate sets, the arithmetic for each, and a written verdict of viable or not viable.
Session 3, schedule the year: Teams choose one viable set. They place each work order on a twelve-month calendar. The calendar must respect the summer rule at Velbury Hill. It must also respect the one-pump-out rule and the mechanic's twelve days a month. Output: a calendar showing each work order, its crew-hours, and its sign-off date.
Session 4, memo and briefing: Teams write the two-page memo. Then they brief the class for five minutes. The briefing must answer one hard question about a pump the team left alone. Output: the finished memo and a briefing with a written answer to that question.
From Water for Schools (waterforschools.org). This material is in the public domain (CC0) and may be copied, edited, and shared freely.
Rubric
| Criterion | Emerging | Developing | Proficient | Advanced |
|---|---|---|---|---|
| Cost-per-year ranking | The ranking is missing or simply lists pumps by age | Some cost-per-added-year figures are computed, yet the ranking is incomplete or contains arithmetic errors | All seven pumps are ranked correctly by cost per added year of service | The ranking is correct and the team explains where criticality should override the pure cost ranking |
| Constraint modeling | No inequality is written and totals are not checked | An inequality is written for one constraint only, or totals are checked informally | Both inequalities are written correctly and each candidate package is tested against both | Both inequalities are written correctly, both packages are tested, and the team identifies which constraint is binding |
| Schedule and certification staffing | The calendar is missing or ignores the stated restrictions | The calendar places work orders yet violates the peak-season rule or the one-pump-out rule | The calendar honors the peak-season, redundancy, and mechanic-availability requirements | The calendar honors every requirement and leaves a stated reserve of crew-hours for emergency repairs |
| Memo and briefing | The memo states a choice with no supporting figures | The memo reports the chosen package yet omits the table, the inequalities, or the calendar | The memo contains every required element and defends one pump left alone | The memo contains every element, defends the deferral, and answers the challenge question with specific figures |
Differentiation
Support
Give teams the cost-per-added-year column already computed for the first three pumps, so they can see the pattern before finishing the remaining four rows. Provide a calendar grid with the July and August cells already shaded, along with a worked example of one inequality built from two pumps.
Extension
Ask teams to test whether replacing a single pump outright, rather than rebuilding two, produces a lower cost per added year over a fifteen-year horizon, and to state what information they would need from the manufacturer to answer that question with confidence.
ELL supports
Pre-teach the terms overhaul, work order, criticality, and crew-hour with a labeled diagram of a pump and motor set. Allow the memo's defense paragraph to be delivered orally to the teacher before it is written, and provide a sentence frame for the viability verdict.
Extensions
Invite a maintenance planner or a public works supervisor to review two teams' calendars and describe how their own agency sets repair priorities. Teams can also convert their chosen package into a bar chart of spending by station, then discuss whether the station with the oldest equipment should always receive the largest share of a repair budget.