Consider the following requirements 1. Removing all the impurities 2. Tapping the water throughout the year 3. Getting water free from suspended and floating solid matter 4. Quantifying the water taken from the source Which among the above mandate that intakes be provided in a water supply scheme?
- A1, 2 and 4
- B1 and 4 only
- C2 and 3 onlyCorrect
- D2, 3 and 4
Solution
Concept
Functions of Intake Structures in Water Supply Systems
Formula
N/A
Step-by-step solution
1. Analyze the functional requirements of intake structures in a water supply scheme. 2. Recognize that intakes continuously draw water from the source (2) and prevent floating or suspended debris from entering (3). 3. Select Option (c) as the correct choice.
Explanation
An intake structure in a water supply scheme is designed to safely draw water from a source all year round regardless of water level changes (Requirement 2). It also uses screens to exclude large debris, floating objects, and heavy suspended solids at the entry point (Requirement 3). Complete purification (1) is handled later by treatment plants, while measuring flow (4) is done using flow meters.
Shortcut
To remember the main functions of Intake Structures, use the rule "Tap & Screen, Not Clean or Measure": - Tap & Screen: Intakes tap water year-round and screen out floating debris (Statements 2 & 3). - Not Clean or Measure: Treatment plants clean impurities and flow meters measure quantity (Statements 1 & 4).
Common mistake
A common mistake is selecting Option D by assuming that flow measurement (quantifying water) is a primary reason for providing an intake structure, whereas flow measurement is performed separately using flow meters. Another frequent error is including statement 1 (Options A or B) under the misconception that intake structures are meant for complete purification, whereas purification is done at water treatment plants.
Correct answer: C) 2 and 3 only