Water Supply and Wastewater Engineering MCQs (Part-4)
What is the primary role of a water treatment plant?
A Treat water
B Pump water
C Store water
D Distribute water
The primary role of a water treatment plant is to remove contaminants from raw water through processes like filtration, coagulation, and disinfection, making it safe for human consumption and use.
What is the purpose of a storage reservoir in a water distribution system?
A Pump water
B Treat water
C Store water
D Filter water
A storage reservoir is used to hold water temporarily, allowing for regulated distribution to consumers. It provides a buffer during peak demand and ensures a continuous supply even during maintenance or emergencies.
Which treatment process removes particles from water by settling?
A Chlorination
B Sedimentation
C Coagulation
D Filtration
Sedimentation involves allowing heavier particles to settle at the bottom of a tank due to gravity. This process helps to remove large particles and clarify the water before further treatment like filtration.
Which of these is a key factor in determining water quality?
A Chlorine
B Turbidity
C Temperature
D All of the above
Water quality is influenced by several factors, including chlorine (disinfection), turbidity (clarity), and temperature (affects microbial growth). All these parameters must be monitored to ensure safe drinking water.
What is the primary use of reverse osmosis in water treatment?
A Remove salts
B Remove bacteria
C Add nutrients
D Remove color
Reverse osmosis is mainly used in desalination to remove salts and other dissolved impurities from seawater, making it suitable for drinking and agricultural use. It uses a semi‐permeable membrane to filter contaminants.
What is the main purpose of coagulation in water treatment?
A Remove large solids
B Kill microorganisms
C Remove suspended particles
D Raise pH levels
Coagulation involves adding chemicals that cause fine suspended particles to clump together, forming larger particles (flocs). These are then removed through sedimentation or filtration to clarify the water.
Which of the following is a common water quality parameter?
A pH
B Phosphorus
C Sodium
D Iron
pH is a common parameter used to assess water quality, indicating whether the water is acidic or alkaline. Maintaining a balanced pH is important for both water quality and treatment efficiency.
What is used to disinfect water at most treatment plants?
A Reverse osmosis
B Chlorine
C Filtration
D Sedimentation
Chlorine is widely used for disinfection in water treatment plants. It kills harmful pathogens such as bacteria and viruses, ensuring the treated water is safe for consumption and free from disease‐causing microorganisms.
Which pipe material is commonly used in water distribution systems?
A PVC
B Concrete
C Lead
D Copper
PVC pipes are commonly used in water distribution systems due to their affordability, ease of installation, and resistance to corrosion. They are durable and widely accepted for both residential and industrial water supply lines.
What is a key feature of septic systems?
A Treat wastewater
B Pump water
C Distribute clean water
D Filter air
Septic systems treat wastewater on‐site, typically in rural or off‐grid areas. They use a tank for settling solids and a leach field for filtering and disposing of effluent, preventing contamination of the surrounding environment.
What is the purpose of filtration in water treatment?
A Increase pressure
B Add chemicals
C Remove solids
D Remove gases
Filtration is a crucial process in water treatment that removes suspended solids, dirt, and debris. It improves the clarity of water and is essential before disinfection and other treatment processes.
What is the purpose of aeration in wastewater treatment?
A Add oxygen
B Remove solids
C Kill bacteria
D Lower temperature
Aeration adds oxygen to wastewater, promoting the growth of aerobic microorganisms that help break down organic matter. It is an important step in both wastewater treatment and water quality improvement.
What is the function of a combined sewer system?
A Treat wastewater
B Collect stormwater and sewage
C Purify water
D Reuse water
A combined sewer system collects both stormwater runoff and sewage in the same pipes. While this system is efficient in dry weather, it can overflow during heavy rain, causing untreated wastewater to discharge into water bodies.
What type of water is collected for greywater recycling?
A Rainwater
B Drinking water
C Wastewater from kitchens
D Wastewater from toilets
Greywater refers to wastewater from non‐toilet household activities like showers, sinks, and laundry. It can be treated and reused for irrigation, cleaning, and other non‐potable uses, reducing overall water consumption.
What does a water quality parameter “turbidity” measure?
A pH level
B Solids content
C Temperature
D Clarity of water
Turbidity measures the cloudiness or haziness of water caused by suspended particles like dirt, bacteria, and algae. High turbidity indicates poor water quality, and it must be reduced to meet safety standards.