1959 Water Purification and Wastewater Treatment: Johns Hopkins Science Review

The video explains the processes involved in purifying natural river water, including settling, coagulation, filtration, and disinfection, resulting in clean but not pure water. It also covers sewage treatment, where organic waste is decomposed, and the resulting effluent can affect river ecosystems by increasing or decreasing organism populations.

What is the purpose of adding coagulants during the water purification process?

• To add minerals to the water

• To remove bacteria

• To speed up the settling of suspended matter

• To disinfect the water

What happens to water after it is used and enters the sewers?

• It is filtered through sand

• It flows through settling tanks to form sludge

• It is immediately disinfected

• It is directly released into rivers

What is the main purpose of the biological processes in sewage treatment?

• To purify the water completely

• To remove all industrial waste

• To decompose organic waste materials

• To increase the water's mineral content

How can the effluent from sewage treatment affect river ecosystems?

• It purifies the river water

• It has no impact on the river

• It can make the river more fertile, affecting plant and animal life

• It always reduces the number of organisms

What is a potential negative effect of increased fertility in river water due to effluent?

• It can cause the river to dry up

• It can cause an overgrowth of plants and animals, becoming a nuisance

• It can lead to a decrease in fish population

• It can make the water too clean for organisms