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A trip through a wastewater treatment plant

Water disappearing down a drain begins another journey before it returns to a river or the sea. Inside a wastewater treatment plant, screens, settling tanks, and microbes tackle different kinds of pollution. Conventional sewage treatment produces effluent for controlled discharge; making recycled water suitable for drinking requires additional treatment and safeguards.

4–5 min

Questions you could explore

  • Which materials can be separated physically?
  • What can biological treatment remove that settling alone cannot?

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Environment and climate

What can tree rings reveal about past climate?

A tree keeps a record of growth in its wood, but reading that record as climate history takes more than counting rings. Moisture, temperature, and other growing conditions can leave overlapping clues.

4–5 min

What can tree rings reveal about past climate?

Environment and climate4–5 minA tree keeps a record of growth in its wood, but reading that record as climate history takes more than counting rings. Moisture, temperature, and other growing conditions can leave overlapping clues.

Environment and climate

Why can a city be warmer than nearby countryside?

The trip from a leafy edge of town to a dense street can also be a trip between different temperatures. Buildings, pavement, vegetation, and waste heat all affect the balance, and the contrast changes with weather and time of day.

3–5 min

Why can a city be warmer than nearby countryside?

Environment and climate3–5 minThe trip from a leafy edge of town to a dense street can also be a trip between different temperatures. Buildings, pavement, vegetation, and waste heat all affect the balance, and the contrast changes with weather and time of day.

Environment and climate

Where does the water go in a rain garden?

Rain runs quickly off a roof or pavement, but a planted hollow can give it somewhere to pause. A rain garden's ability to hold water and let it enter the soil depends on its surroundings and ground conditions.

3–5 min

Where does the water go in a rain garden?

Environment and climate3–5 minRain runs quickly off a roof or pavement, but a planted hollow can give it somewhere to pause. A rain garden's ability to hold water and let it enter the soil depends on its surroundings and ground conditions.

A trip through a wastewater treatment plant | Speech Topic | speaking.app