Water for Schools
Menu

Worksheet Grade 10 English Language Arts

Sable Creek Pump Log: A Grade 10 Flow-Rate Conversion Worksheet

A grade 10 worksheet in which students read a fictional pump station's field log and convert flow rates between million gallons per day, gpm, and cfs.

Objectives

  1. Students will follow a multistep technical field log and identify its stated exception.
  2. Students will convert flow rates between MGD, gpm, and cfs using standard conversion factors.
  3. Students will compare two pumps' capacities using converted units.

Vocabulary

Key words: wet well, discharge pressure, gpm, MGD, backup pump

Teacher overview

A pump station field log looks plain, but it is written the way it is for a reason: every entry has to be precise enough that a different technician, reading it hours or days later, can reconstruct exactly what happened and why. This worksheet uses a fictional log from Sable Creek Pump Station to give students a real technical-reading task, then pairs it with flow-rate conversions using the same rates a water distribution operator works with daily: gallons per minute, million gallons per day, and cubic feet per second.

Sable Creek Pump Log: A Grade 10 Flow-Rate Conversion Worksheet — Grade 10 English Language Arts
Name: ____________________________ Date: ______________

Student Worksheet

Read this fictional log from Sable Creek Pump Station, then answer the questions that follow. Use these conversions where needed: 1 MGD = 694 gallons per minute (gpm); 1 cubic foot per second (cfs) = 448.8 gpm.

Sable Creek Pump Station -- Morning Startup Log

  • 06:00 -- Technician arrives and checks the static water level in the wet well.
  • 06:05 -- Opens the discharge valve halfway before starting Pump 1, to avoid a pressure surge.
  • 06:07 -- Starts Pump 1. Pump ramps up to full speed over 90 seconds.
  • 06:10 -- Records Pump 1 output: 2.0 MGD at a discharge pressure of 45 psi.
  • 06:12 -- Fully opens the discharge valve now that Pump 1 is running at full speed.
  • 06:15 -- Exception: if Pump 1 has not reached 40 psi of discharge pressure by this time, the technician must shut it down, start backup Pump 2, and note the failure in the maintenance log.
  • 07:00 -- Pump 2 (backup) rated capacity: 1.5 MGD; used only when Pump 1 is down for maintenance or fails to reach pressure.
  1. What is the first action the technician takes in the log, before starting either pump?
  2. Why does the technician open the discharge valve only halfway before starting Pump 1, rather than fully open?
  3. What is the exception written into the 06:15 log entry?
  4. Explain in your own words why a pump station would write this exception into its procedure rather than leaving the decision to the technician's judgment in the moment.
  5. Pump 1's recorded output is 2.0 MGD. Convert this to gallons per minute (gpm).
  6. Pump 2's rated capacity is 1.5 MGD. Convert this to gallons per minute (gpm).
  7. If Pump 1 runs at its converted gpm rate for one full hour, how many gallons does it pump in that hour? Round to the nearest hundred gallons.
  8. A neighboring pump station reports a flow of 3 cubic feet per second (cfs). Convert this to gallons per minute (gpm), rounded to the nearest whole gpm.
  9. Which pump, 1 or 2, moves more water per minute, and by about how many gpm?
  10. Using the log, explain what "discharge pressure" measures and why a technician tracks it during startup.
  11. A third pump at Sable Creek is rated at 4.0 MGD. Convert this to gallons per minute (gpm).

From Water for Schools (waterforschools.org). This material is in the public domain (CC0) and may be copied, edited, and shared freely.

Answer Key
  1. Answer: Checks the static water level in the wet well.
    The 06:00 entry is the first line of the log, before any valve or pump action begins.
  2. Answer: To avoid a pressure surge.
    The log states this reason directly at 06:05, before Pump 1 starts.
  3. Answer: If Pump 1 has not reached 40 psi by 06:15, shut it down and start backup Pump 2.
    The 06:15 entry states this special case explicitly and requires logging the failure.
  4. Answer: A written exception ensures every technician handles the same situation the same way, rather than relying on one person's judgment in the moment, which keeps the station's response consistent no matter who is on shift.
    Accept any answer connecting consistency, safety, or accountability to the reason a station would formalize the rule in writing.
  5. Answer: 1,388 gpm.
    2.0 MGD x 694 gpm/MGD = 1,388 gpm.
  6. Answer: 1,041 gpm.
    1.5 MGD x 694 gpm/MGD = 1,041 gpm.
  7. Answer: 83,300 gal.
    1,388 gpm x 60 minutes = 83,280 gallons, which rounds to 83,300 gallons.
  8. Answer: 1,346 gpm.
    3 cfs x 448.8 gpm/cfs = 1,346.4 gpm, which rounds to 1,346 gpm.
  9. Answer: Pump 1, by about 347 gpm.
    1,388 gpm (Pump 1) minus 1,041 gpm (Pump 2) = 347 gpm.
  10. Answer: Discharge pressure measures how hard the pump is pushing water out into the system, and a technician tracks it during startup because a reading below the 40 psi threshold signals the pump is not performing correctly and the backup should take over.
    Accept any answer that connects discharge pressure to pump performance and the 06:15 exception.
  11. Answer: 2,776 gpm.
    4.0 MGD x 694 gpm/MGD = 2,776 gpm.

Differentiation

Support (below grade level)

Provide the two conversion factors as a labeled reference card ("MGD to gpm: multiply by 694" / "cfs to gpm: multiply by 448.8") and allow a calculator for every numeric item.

Extension (above grade level)

Ask students to convert Pump 1's 2.0 MGD output to cubic feet per second (cfs) using the conversion 1 MGD = 1.547 cfs, then explain which unit, gpm or cfs, they think is easier to picture and why.

ELL supports

Pre-teach "wet well," "discharge pressure," "gpm," "MGD," and "backup pump" with a simple labeled diagram of a pump station (wet well, pump, discharge pipe, pressure gauge). Allow items 4 and 10 to be answered with a short phrase rather than a full sentence.