Question

A town with a population of 50,000 has a water supply of 135 LPCD. Find the average daily demand:

• A. 5.4 MLD
• B. 6.75 MLD
• C. 7.5 MLD
• D. 8.1 MLD

Hint:

To convert quickly to MLD without writing down all the zeros: \[ Q = \left(\frac{\text{Population in Thousands}}{1000}\right) \times \text{LPCD} \times 10^{-3} \] \[ Q = 50 \times 135 \times 10^{-3} = 6.75 \text{ MLD} \]

Answer 1

The Correct Option is B

Concept: In municipal water supply engineering, the average daily water demand of a community represents the total volume of water consumed over a 24-hour period. It is calculated by multiplying the total population by the per capita water consumption rate, which is measured in Liters Per Capita Per Day (LPCD). The final volume is typically expressed in Millions of Liters per Day (MLD).

Step 1: Extracting given parameters from the problem statement.
The problem provides the following data:
• Total permanent municipal population, $P = 50,000 \text{ citizens}$
• Rate of water supply per individual per day, $q = 135 \text{ Liters/capita/day (LPCD)}$

Step 2: Mathematical formulation and computation.
The total average daily water volume ($Q$) requested by the municipality is given by: \[ Q = \text{Population} \times \text{Per Capita Water Supply Rate} \] Substituting our values into the formula: \[ Q = 50,000 \times 135 \text{ Liters/day} \] Let us compute this multiplication systematically: \[ Q = 6,750,000 \text{ Liters/day} \]

Step 3: Converting units to Millions of Liters per Day (MLD).
By definition, one Million Liters per Day (1 MLD) is equivalent to $10^6 \text{ Liters/day}$: \[ Q_{\text{MLD}} = \frac{6,750,000}{1,000,000} = 6.75 \text{ MLD} \] This calculated value matches Option B.