Two sub-basins in a catchment have been earmarked for settling displaced persons. The rainfall characteristics typical of the watershed is presented as follows: Typical Rainstorm Time from start (mins) 0-15 15-30 Rainfall depth (mm) 2.5 3.5 4.0 30-45 45-60 3.2 60-75 5.0 75-90 3.5 Sub-basin characteristics Sub-basin characteristics Flow length Average slope (%) % Silt % Clay Soil Structure Permeability Land-use Organic Matter Content Very fine sand P-Factor Sub basin A Sub-basin B 300 m 200 m 3 4 60 50 20 30 Coarse granular Fine granular moderate Arable 2% 10 0.1 Fine granular Established grass 3% 5 0.15 Catchment A is arable with C-factor of 0.2. The rainfall erosivity index is computed as R = El 30/100. Determine the following; (i) (ii) Compute the Weischmeier index using the Weischemeier equation. KE 11.87+8.73 Which of the two catchments are at risk of degradation by erosion if it were to be used to settle the displaced persons if the C-factor for settlement is 0.3? The permissible soil loss is 10 tons/acre-year (Hint: use the USLE). (iii) Using the Erosion Hazard Classification for lowlands of Lesotho technique, Assess the erosion hazard for each catchment resulting from the proposed change in land use to settlement i.e before and after the change in land use.
Two sub-basins in a catchment have been earmarked for settling displaced persons. The rainfall characteristics typical of the watershed is presented as follows: Typical Rainstorm Time from start (mins) 0-15 15-30 Rainfall depth (mm) 2.5 3.5 4.0 30-45 45-60 3.2 60-75 5.0 75-90 3.5 Sub-basin characteristics Sub-basin characteristics Flow length Average slope (%) % Silt % Clay Soil Structure Permeability Land-use Organic Matter Content Very fine sand P-Factor Sub basin A Sub-basin B 300 m 200 m 3 4 60 50 20 30 Coarse granular Fine granular moderate Arable 2% 10 0.1 Fine granular Established grass 3% 5 0.15 Catchment A is arable with C-factor of 0.2. The rainfall erosivity index is computed as R = El 30/100. Determine the following; (i) (ii) Compute the Weischmeier index using the Weischemeier equation. KE 11.87+8.73 Which of the two catchments are at risk of degradation by erosion if it were to be used to settle the displaced persons if the C-factor for settlement is 0.3? The permissible soil loss is 10 tons/acre-year (Hint: use the USLE). (iii) Using the Erosion Hazard Classification for lowlands of Lesotho technique, Assess the erosion hazard for each catchment resulting from the proposed change in land use to settlement i.e before and after the change in land use.
Elements Of Electromagnetics
7th Edition
ISBN:9780190698614
Author:Sadiku, Matthew N. O.
Publisher:Sadiku, Matthew N. O.
ChapterMA: Math Assessment
Section: Chapter Questions
Problem 1.1MA
Related questions
Question
Transcribed Image Text:Two sub-basins in a catchment have been earmarked for settling displaced persons. The
rainfall characteristics typical of the watershed is presented as follows:
Typical Rainstorm
Time from start (mins)
0-15
15-30
Rainfall depth (mm)
2.5
3.5
4.0
30-45 45-60
3.2
60-75
5.0
75-90
3.5
Sub-basin characteristics
Sub-basin characteristics
Flow length
Average slope (%)
% Silt
% Clay
Soil Structure
Permeability
Land-use
Organic Matter Content
Very fine sand
P-Factor
Sub basin A
Sub-basin B
300 m
200 m
3
4
60
50
20
30
Coarse granular Fine granular
moderate
Arable
2%
10
0.1
Fine granular
Established grass
3%
5
0.15
Catchment A is arable with C-factor of 0.2. The rainfall erosivity index is computed as
R = El 30/100. Determine the following;
(i)
(ii)
Compute the Weischmeier index using the Weischemeier equation.
KE 11.87+8.73
Which of the two catchments are at risk of degradation by erosion if it were to be
used to settle the displaced persons if the C-factor for settlement is 0.3? The
permissible soil loss is 10 tons/acre-year (Hint: use the USLE).
(iii) Using the Erosion Hazard Classification for lowlands of Lesotho technique,
Assess the erosion hazard for each catchment resulting from the proposed change
in land use to settlement i.e before and after the change in land use.
Expert Solution
This question has been solved!
Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.
Step by step
Solved in 2 steps
Recommended textbooks for you
Elements Of Electromagnetics
Mechanical Engineering
ISBN:
9780190698614
Author:
Sadiku, Matthew N. O.
Publisher:
Oxford University Press
Mechanics of Materials (10th Edition)
Mechanical Engineering
ISBN:
9780134319650
Author:
Russell C. Hibbeler
Publisher:
PEARSON
Thermodynamics: An Engineering Approach
Mechanical Engineering
ISBN:
9781259822674
Author:
Yunus A. Cengel Dr., Michael A. Boles
Publisher:
McGraw-Hill Education
Elements Of Electromagnetics
Mechanical Engineering
ISBN:
9780190698614
Author:
Sadiku, Matthew N. O.
Publisher:
Oxford University Press
Mechanics of Materials (10th Edition)
Mechanical Engineering
ISBN:
9780134319650
Author:
Russell C. Hibbeler
Publisher:
PEARSON
Thermodynamics: An Engineering Approach
Mechanical Engineering
ISBN:
9781259822674
Author:
Yunus A. Cengel Dr., Michael A. Boles
Publisher:
McGraw-Hill Education
Control Systems Engineering
Mechanical Engineering
ISBN:
9781118170519
Author:
Norman S. Nise
Publisher:
WILEY
Mechanics of Materials (MindTap Course List)
Mechanical Engineering
ISBN:
9781337093347
Author:
Barry J. Goodno, James M. Gere
Publisher:
Cengage Learning
Engineering Mechanics: Statics
Mechanical Engineering
ISBN:
9781118807330
Author:
James L. Meriam, L. G. Kraige, J. N. Bolton
Publisher:
WILEY