Civil Engineering (CE) Exam  >  Civil Engineering (CE) Questions  >  The drainage discharge of a town of 16 hectar... Start Learning for Free
The drainage discharge of a town of 16 hectares area, consisting of 40% hard paved (k = 0.8), 30% unpaved (k = 0.20), and remaining as wooded (k =0.1), with a max. rain intensity of 5 cm/hr, would be computed by Rational formula, as equal to
  • a)
    0.91 cumecs
  • b)
    0.091 cumecs
  • c)
    9.1 cumecs
  • d)
    None of these
Correct answer is option 'A'. Can you explain this answer?
Verified Answer
The drainage discharge of a town of 16 hectares area, consisting of 40...
View all questions of this test
Most Upvoted Answer
The drainage discharge of a town of 16 hectares area, consisting of 40...
Calculation of Drainage Discharge Using Rational Formula

Given:
Area of town = 16 hectares
Percentage of hard paved area = 40%
Percentage of unpaved area = 30%
Percentage of wooded area = 30%
Maximum rain intensity = 5 cm/hr

Step 1: Calculation of Runoff Coefficient (C)

The runoff coefficient (C) can be calculated using the following formula:

C = (C1 × A1 + C2 × A2 + C3 × A3) / A

Where C1, C2, and C3 are the runoff coefficients for hard paved, unpaved, and wooded areas respectively. A1, A2, and A3 are the areas of hard paved, unpaved, and wooded areas respectively. A is the total area of the town.

Substituting the given values, we get:

C = (0.8 × 40% + 0.2 × 30% + 0.1 × 30%) / 100%
C = 0.42

Step 2: Calculation of Time of Concentration (Tc)

The time of concentration (Tc) is the time taken for the rainwater to travel from the most remote point of the town to the outlet. It can be calculated using the following formula:

Tc = L / V

Where L is the length of the longest flow path and V is the average velocity of flow.

Since the town is assumed to be flat, the length of the longest flow path can be taken as the diagonal of the town. Assuming the town to be square, the diagonal can be calculated as:

Diagonal = √(16 hectares × 10000 m^2/hectare × 4) = 800 m

The velocity of flow can be assumed as:

V = 0.6 × √S

Where S is the slope of the land. Assuming the slope to be 1%, we get:

V = 0.6 × √1% = 0.06 m/s

Substituting the values, we get:

Tc = 800 m / 0.06 m/s = 13333 s

Step 3: Calculation of Design Rainfall Intensity (I)

The design rainfall intensity (I) can be obtained from the rainfall intensity-duration-frequency (IDF) curves for the location. Assuming a maximum rainfall intensity of 5 cm/hr, we can take the design rainfall intensity as:

I = 0.8 × 5 cm/hr = 4 cm/hr = 0.04 m/hr

Step 4: Calculation of Drainage Discharge (Q)

The drainage discharge (Q) can be calculated using the Rational formula:

Q = C × A × I / 3600

Substituting the values, we get:

Q = 0.42 × 16 hectares × 10000 m^2/hectare × 0.04 m/hr / 3600 s/hr
Q = 0.91 cumecs

Therefore, the drainage discharge of the town is 0.91 cumecs.
Explore Courses for Civil Engineering (CE) exam

Similar Civil Engineering (CE) Doubts

Top Courses for Civil Engineering (CE)

The drainage discharge of a town of 16 hectares area, consisting of 40% hard paved (k = 0.8), 30% unpaved (k = 0.20), and remaining as wooded (k =0.1), with a max. rain intensity of 5 cm/hr, would be computed by Rational formula, as equal toa)0.91 cumecsb)0.091 cumecsc)9.1 cumecsd)None of theseCorrect answer is option 'A'. Can you explain this answer?
Question Description
The drainage discharge of a town of 16 hectares area, consisting of 40% hard paved (k = 0.8), 30% unpaved (k = 0.20), and remaining as wooded (k =0.1), with a max. rain intensity of 5 cm/hr, would be computed by Rational formula, as equal toa)0.91 cumecsb)0.091 cumecsc)9.1 cumecsd)None of theseCorrect answer is option 'A'. Can you explain this answer? for Civil Engineering (CE) 2024 is part of Civil Engineering (CE) preparation. The Question and answers have been prepared according to the Civil Engineering (CE) exam syllabus. Information about The drainage discharge of a town of 16 hectares area, consisting of 40% hard paved (k = 0.8), 30% unpaved (k = 0.20), and remaining as wooded (k =0.1), with a max. rain intensity of 5 cm/hr, would be computed by Rational formula, as equal toa)0.91 cumecsb)0.091 cumecsc)9.1 cumecsd)None of theseCorrect answer is option 'A'. Can you explain this answer? covers all topics & solutions for Civil Engineering (CE) 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for The drainage discharge of a town of 16 hectares area, consisting of 40% hard paved (k = 0.8), 30% unpaved (k = 0.20), and remaining as wooded (k =0.1), with a max. rain intensity of 5 cm/hr, would be computed by Rational formula, as equal toa)0.91 cumecsb)0.091 cumecsc)9.1 cumecsd)None of theseCorrect answer is option 'A'. Can you explain this answer?.
Solutions for The drainage discharge of a town of 16 hectares area, consisting of 40% hard paved (k = 0.8), 30% unpaved (k = 0.20), and remaining as wooded (k =0.1), with a max. rain intensity of 5 cm/hr, would be computed by Rational formula, as equal toa)0.91 cumecsb)0.091 cumecsc)9.1 cumecsd)None of theseCorrect answer is option 'A'. Can you explain this answer? in English & in Hindi are available as part of our courses for Civil Engineering (CE). Download more important topics, notes, lectures and mock test series for Civil Engineering (CE) Exam by signing up for free.
Here you can find the meaning of The drainage discharge of a town of 16 hectares area, consisting of 40% hard paved (k = 0.8), 30% unpaved (k = 0.20), and remaining as wooded (k =0.1), with a max. rain intensity of 5 cm/hr, would be computed by Rational formula, as equal toa)0.91 cumecsb)0.091 cumecsc)9.1 cumecsd)None of theseCorrect answer is option 'A'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of The drainage discharge of a town of 16 hectares area, consisting of 40% hard paved (k = 0.8), 30% unpaved (k = 0.20), and remaining as wooded (k =0.1), with a max. rain intensity of 5 cm/hr, would be computed by Rational formula, as equal toa)0.91 cumecsb)0.091 cumecsc)9.1 cumecsd)None of theseCorrect answer is option 'A'. Can you explain this answer?, a detailed solution for The drainage discharge of a town of 16 hectares area, consisting of 40% hard paved (k = 0.8), 30% unpaved (k = 0.20), and remaining as wooded (k =0.1), with a max. rain intensity of 5 cm/hr, would be computed by Rational formula, as equal toa)0.91 cumecsb)0.091 cumecsc)9.1 cumecsd)None of theseCorrect answer is option 'A'. Can you explain this answer? has been provided alongside types of The drainage discharge of a town of 16 hectares area, consisting of 40% hard paved (k = 0.8), 30% unpaved (k = 0.20), and remaining as wooded (k =0.1), with a max. rain intensity of 5 cm/hr, would be computed by Rational formula, as equal toa)0.91 cumecsb)0.091 cumecsc)9.1 cumecsd)None of theseCorrect answer is option 'A'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice The drainage discharge of a town of 16 hectares area, consisting of 40% hard paved (k = 0.8), 30% unpaved (k = 0.20), and remaining as wooded (k =0.1), with a max. rain intensity of 5 cm/hr, would be computed by Rational formula, as equal toa)0.91 cumecsb)0.091 cumecsc)9.1 cumecsd)None of theseCorrect answer is option 'A'. Can you explain this answer? tests, examples and also practice Civil Engineering (CE) tests.
Explore Courses for Civil Engineering (CE) exam

Top Courses for Civil Engineering (CE)

Explore Courses
Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
10M+ students study on EduRev