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A River's Tale (Smart Water Pollution TDS & Turbidity Lab)

Source: Stemoto Original

Track a river's journey from clean mountain spring to polluted city river. Use a TDS (Total Dissolved Solids) sensor probe and optical turbidity sensor to test water purity samples, displaying PPM pollution levels.

Categorisation

Stage 2: Builder (8-10)Pattern Recognition & Data AnalysisSystemic & Design ThinkingTabletop & Physical PropsSTEM Experiment

Props & Materials Required

  • 3 water sample jars (Mountain Spring, Village Stream, City Factory River)
  • Analog TDS (Total Dissolved Solids) meter sensor probe
  • TS-300B optical turbidity sensor module
  • ESP32 controller board
  • 16x2 LCD display screen
  • DFPlayer Mini MP3 module + 3W speaker

Step-by-Step Instructions

1

Test Mountain Spring Sample

Insert TDS probe into Mountain Spring sample jar.

2

Read Pure Water TDS

LCD displays 'TDS: 45 PPM | Turbidity: CLEAR'. Speaker: 'PURE DRINKING WATER! Clean mountain source!'

3

Test City Factory River Sample

Insert TDS probe into City River sample containing soap/salt contaminants.

4

Read Polluted Water Warning

LCD displays 'TDS: 850 PPM | Turbidity: MURKY!'. Red LED flashes + Speaker warns: 'HIGH POLLUTION! Industrial waste detected! Unsafe for fish!'

Why It Works & Notes

A River's Tale illustrates how rivers get polluted as they flow past villages and cities. Testing real water samples with digital TDS probes (measuring dissolved salts/chemicals in PPM) makes water quality scientifically measurable.

Parent Note:

Looking Around Chapter 13: A River's Tale | STEM Tech: Electro-Conductivity TDS Probing & Optical Turbidity Pollution Telemetry — municipal water quality testing.