Text of Paper presented at the International Conference on Modeling, Optimization, and Computing, ICMOC 2014, N.I. University, Kumaracoil, Tamil Nadu State, India, April 10-11, 2014.

1. The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT Nitte, India
A Keynote paper
Delivered @ ICMOC 2014
of the NI University,
Kumaracoil- 629 180
Tamil Nadu State, India
by
SAMSON O. OJOAWO, Ph.D
Wednesday 10thApril, 2014
1
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

2. OUTLINE
INTRODUCTION
METHODOLOGY
RESULTS AND DISCUSSION
CONCLUSION
CONTRIBUTIONS TO KNOWLEDGE
REFERENCES
2
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

3. INTRODUCTION
(a) Definition of key Technical terms
System Dynamics (SD)
SD is a computer-aided approach to policy
analysis and design. It applies to dynamic
problems arising in complex social, managerial,
economic, or ecological systems
- System Dynamics Society, 2011
Sewer Effluent
A conduit carrying sewage that has been treated in
a wastewater treatment plant or other liquid
waste like storm water that is flowing from the
source and discharged into a body of water
- Punmia et al., 20123
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

4. 4
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

5. 5
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

6. 6
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

7. (b) Brief Literature Review
 SD is a well-established methodology for studying and
managing complex feedback systems, based on system
thinking (Dyson and Chang, 2005)
 SD modeling has a wide practical application. It has been
used to address various feedback systems, including the
environmental management (Vizayakumar and Mohapatra,
1991, 1993; Vezjak et al., 1998; Deaton and Winebrake, 2000)
 The development processes of SD had been well documented
(Forrester, 1961, 1968; Randers, 1980; Richardson and Pugh,
1981; Sufian, 2001)
7
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

8. Figure 1: In SD, Stella diagram showing stock, flows, variables and converter
 SD requires constructing the unique ‘‘causal loop
diagrams’’ or ‘‘stock and flow diagram’’ to form a
system dynamics model for applications
8
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

9. Building blocks of SD (Bala, 1999)
• Two basic building blocks in SD
studies are stock or level & flow or
rate
• Stock variables, denoted by
rectangles, are state variables and
stocks represent accumulation in
the system
• Valve symbols stand for flow
variables
• Converters, represented by circles,
are intermediate variables used for
miscellaneous calculations
• The connectors which are indicated
by simple arrows symbolize cause
and effect links within the model
structure 9
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

10. • Mashayekhi (1993) explored the analysis of the New York
State solid waste system
• Also, Sudhir, 1997 employed a SD model to capture the
dynamic nature of interactions among the various
components in the urban solid waste management system
• Karavezyris, 2002 developed a methodology to incorporate
qualitative variables such as voluntary recycling
participation and regulation impact quantitatively
• Other previous applications in different topical areas are
collated in SD Review (Abbott, 1999)
10
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

11. • The simulation of SD scenarios is usually
being accomplished with the Stella software
package
• Stella is an iconographic software that uses
intuitively assembled basic building blocks
such as stocks, flows, and converters to
simulate the dynamic processes of a system
• Apart from Stella, Vensim is another
software with a user-friendly interface for
most computer SD model simulation
applications (Dyson and Chang, 2005) 11
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

12. • Model development procedures:
- visualization
- conceptualization
- documentation
- simulation
- analysis
• SD offers a flexible way for:
- building a variety of simulation models from causal
loops or stock and flow
- creating dynamic relationships between the elements,
including variables, parameters, and their linkages,
can be created onto the interface using user-friendly
visual tools
- The feedback loops associated with these employed
variables can be visualized at every step throughout the
modeling process
- Simulation runs are carried out entirely along the 12
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

13. • The paper looks at the application of the
flexible and versatile SD in optimizing the
sewer effluents at NMAM Institute of
Technology Campus, Nitte, Udupi District,
India.
• The direct relationships studied using SD are
those between Design Discharge and:
– Population
– water supply
– sewage flow
– rainfall intensity
13
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

14. METHODOLOGY
 The study area
• Nitte is a Village in Karkal Taluk in Udupi District of Karnataka
State, India
• It is located 30 km towards East from District head quarters
Udupi, 6 km from Karkal and 336 km from the State capital
Bangalore
• The study area’s elevation/altitude is 20 meters above sea level
• Udupi district experiences a typical maritime climate with an
average temperature of 26.5°C
• The district gets highest annual rainfall in Karnataka state, about
4000 mm
• Average Annual Rainfall is 4136.3 mm (Central Groundwater Board,
South Western Region, Bangalore, 2008)
14
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

15. NMAMIT Pictorial View 15
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

16. Fig. 1: Udupi District Map, Karnataka State, India16
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

17. Fig. 2: The Digitized Map of NMAMIT Campus17
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

18. Fig. 3: NMAMIT Layout Plan 18
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

19.  Design parameters
SD model for the Design Discharge (Q) and Effluent (E):
 Population (P)
 Catchment Area (A)
 Impervious Area (Ai)
 Per capita water supply (WS)
 Sewage Flow (SF)
 Wet Weather Flow (WWF)
 Dry Weather Flow (DWF)
 Average Annual Rainfall (AAR)
 Rainfall Intensity (Ri)
 Sewage % from water supply (75)
 Average Impermeability, Coefficient for the area (I)
 Time of concentration (tc)
 Ri constants (a and b) as defined by the US Ministry
of Health. 19
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

20.  Governing equations:
• Rational Formular (RF), WWF = 28AIRi ………………. (1)
• US Ministry of Health Formula, Ri = 25.4a/( tc + b)……. (2)
• Lloyed Davis Formular (LDF), WWF = [Ri/6tc].Ai ….....(3)
 Basic Relationships:
• SF = 0.75 * WS ………………………………………….. (4)
• DWF = P * SF ………………………….…...……………. (5)
• Q = WWF + (2 * DWF) ………………………………....... (6)
20
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

21. Year/Session Estimated
Population of
Boarders
Estimated
Population of
Non-Boarders
Total Estimated
population on
campus
2010/2011 1, 015 5, 258 6, 273
2011/2012 1, 699 4, 742 6, 441
2012/2013 1, 885 5, 069 6, 954
2013/2014 2, 156 5, 219 7, 375
Table 1: The Estimated Population of NMAMIT Campus
21
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

22.  Model development
• Water demands:
- for institutions are 135 l/c/p (hostel)
- 45 l/c/d (non-boarders)
- BIS (IS 1172:1993)
• The model equations (1-6) were coded in the Visual Basic language
• The variables were either defined or quantified as key elements of the
model
• As soon as the parameters and the initial values for the State Variables
(Stocks) were specified, the model became definitively determined
through the program
• STELLA 9.0 software and simulation package was employed in the
development of the stock flow diagram of the system
• The principles of SD were applied to determine the interrelationships of
P with the WF and sewage flow
• Causal loops indicating the linkage of P, SF, I and tc to Q were
developed 22
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

23. Wet Weather Flow
Rate of
Water
Supply
Sewage Flow
Rainfall
Intensity
Dry Weather Flow
Population
a
b
Time of concentration
Catchment
Area
Design Discharge
Effluent
Present
Population
Off
Campus
Boarders
Total Rainfall
Impervious Area
Fig. 4: Stella flow diagram of the design23
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

24. • The flow diagram connects the key variables of
population to the main outputs which is the Design
Discharge, Q
• The Rational Formular (RF) and Lloyed Davis Formular
(LDF) were alternately employed in the design discharge
optimization, hinged basically on P
• The flexibility of the model is strongly hinged on P;
negative P designed using LDF, while the positive P used
RF
• The model validation is considered necessary so as to
compare the model results with historical data, and to
check whether the model generates plausible behaviour
• The developed model was validated by applying it in
solving the practical problems of various Q values, using
data from the study area until the optimized Q value is
obtained.
24
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

25. (a) Results
• The SD model outputs for the RF method are as presented in
Figures 5 to 9
RESULTS AND DISCUSSION
11:26 AM Sun, Mar 16, 2014
GRAPH OF THE SEWAGE EFFLUENT DESIGN DISCHARGE
Page 1
0.00 3.00 6.00 9.00 12.00
Time
1:
1:
1:
2:
2:
2:
3:
3:
3:
4:
4:
4:
5:
5:
5:
5000
50000
95000
0
100
200
1
2
2
400
550
700
2155
2156
2157
1: Population 2: Dry Weather Flow 3: Rainf all Intensity 4: Design Discharge 5: Boarders
1
1
1
1
2
2
2
23 3 3 3
4
4
4
4
5 5 5 5
Figure 5: The graph relating design discharge and the
key input parameters in RF method 25
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

26. 12:15 PM Sun, Mar 16, 2014
COMPARISON OF RAINFALL INT…ER AND THE DRY WEATHER FLOWS
Page 1
0.00 3.00 6.00 9.00 12.00
Time
1:
1:
1:
2:
2:
2:
3:
3:
3:
1
2
2
0
100
200
412
412
413
1: Rainfall Intensity 2: Dry Weather Flow 3: Wet Weather Flow
1 1 1 1
2
2
2
2
3 3 3 3
Figure 6: The graph relating Ri, DWF and WWF in RF method26
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

27. 11:30 AM Sun, Mar 16, 2014
RELATIONSHIP OF POPULATION …FALL INTENSITY WITH DISCHARGE
Page 1
0.00 3.00 6.00 9.00 12.00
Time
1:
1:
1:
2:
2:
2:
3:
3:
3:
4:
4:
4:
5000
50000
95000
1
2
2
7374
7375
7376
400
550
700
1: Population 2: Rainfall Intensity 3: Present Population 4: Design Discharge
1
1
1
1
2 2 2 2
3 3 3 3
4
4
4
4
Figure 7: The graph relating Ri, P and Q in RF method27
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

28. 11:32 AM Sun, Mar 16, 2014
COMPARISON OF EFFLUENT AND THE DESIGN DISCHARGE OUTPUTS
Page 1
0.00 3.00 6.00 9.00 12.00
Time
1:
1:
1:
2:
2:
2:
248
248
249
400
550
700
1: Effluent 2: Design Discharge
1 1 1 1
2
2
2
2
Figure 8: The graph relating E and Q in RF method28
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

29. 11:30 AM Sun, Mar 16, 2014
RELATIONSHIP OF TIME OF CON…NSTANTS AND DESIGN DISCHARGE
Page 1
0.00 3.00 6.00 9.00 12.00
Time
1:
1:
1:
2:
2:
2:
3:
3:
3:
4:
4:
4:
400
550
700
49
50
51
39
40
41
19
20
21
1: Design Discharge 2: Time of concentration 3: a 4: b
1
1
1
1
2 2 2 23 3 3 34 4 4 4
Figure 9: The graph relating Q, tc and the constants in RF method29
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

30. 11:58 AM Sun, Mar 16, 2014
GRAPH OF THE SEWAGE EFFLUENT DESIGN DISCHARGE
Page 1
0.00 3.00 6.00 9.00 12.00
Time
1:
1:
1:
2:
2:
2:
3:
3:
3:
4:
4:
4:
5:
5:
5:
-5000
45000
95000
-50
50
150
1
2
2
200
450
700
2155
2156
2157
1: Population 2: Dry Weather Flow 3: Rainf all Intensity 4: Design Discharge 5: Boarders
1
1
1
1
2
2
2
2
3 3 3 3
4
4
4
4
5 5 5 5
• The SD model outputs for the LDF method are as presented in
Figures 10 to 14
Figure 10: The graph relating design discharge and the key parameters in LDF method
30
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

31. 11:58 AM Sun, Mar 16, 2014
COMPARISON OF RAINFALL INT…ATHER AND WET WEATHER FLOWS
Page 1
0.00 3.00 6.00 9.00 12.00
Time
1:
1:
1:
2:
2:
2:
3:
3:
3:
1
2
2
-50
50
150
412
412
413
1: Rainfall Intensity 2: Dry Weather Flow 3: Wet Weather Flow
1 1 1 1
2
2
2
2
3 3 3 3
Figure 11: The graph relating Ri, DWF and WWF in LDF method31
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

32. 11:58 AM Sun, Mar 16, 2014
RELATIONSHIP OF POPULATION …FALL INTENSITY WITH DISCHARGE
Page 1
0.00 3.00 6.00 9.00 12.00
Time
1:
1:
1:
2:
2:
2:
3:
3:
3:
4:
4:
4:
-5000
45000
95000
1
2
2
7374
7375
7376
200
450
700
1: Population 2: Rainfall Intensity 3: Present Population 4: Design Discharge
1
1
1
1
2 2 2 2
3 3 3 34
4
4
4
Figure 12: The graph relating Ri, P and Q in LDF method32
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

33. 11:58 AM Sun, Mar 16, 2014
RELATIONSHIP OF TIME OF CON…NSTANTS AND DESIGN DISCHARGE
Page 1
0.00 3.00 6.00 9.00 12.00
Time
1:
1:
1:
2:
2:
2:
3:
3:
3:
4:
4:
4:
200
450
700
49
50
51
39
40
41
19
20
21
1: Design Discharge 2: Time of concentration 3: a 4: b
1
1
1
1
2 2 2 23 3 3 34 4 4 4
Figure 13: The graph relating Q, tc and the constants in LDF method33
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

34. 11:58 AM Sun, Mar 16, 2014
COMPARISON OF EFFLUENT AND DESIGN DISCHARGE OUTPUTS
Page 1
0.00 3.00 6.00 9.00 12.00
Time
1:
1:
1:
2:
2:
2:
248
248
249
200
450
700
1: Effluent 2: Design Discharge
1 1 1 1
2
2
2
2
Figure 14: The graph relating E and Q in LDF method34
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

35. Discussions
• The optimum DWF and WWF in the RF were 111 and 412 l/s
• while in the LDF they were 103 and 412 l/s respectively
• The optimum effluent design discharge according to the RF
from the model is 637 l/s
• while from the LDF it was 617 l/s
• Considering the ratios, in the RF the DWF/WWF ratio gives
(111/412) which is 1:3.7
• while in the LDF the ratio is (103/412) which is 1:4
• Since this ratio is not very large, it is preferable to use a
combine sewer system for the study area.
35
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

36. CONCLUSION
• The study has applied the principles of System Dynamics
(SD) for the optimization of sewer effluent design
discharge
• Rational Formular (RF) and Lloyed Davis Formular
(LDF) methods were both employed
• Population status was the determinant input
• The optimum DWF and WWF in the RF method were 111
and 412 l/s while in the LDF they were 103 and 412 l/s
respectively.
• The optimum effluent design discharge obtained for the
RF and LDF methods were 637 l/s and 617 l/s respectively
• The DWF/WWF ratio was found as 1:4. The study
therefore recommends combine sewer system for the
study area. 36
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

37. CONTRIBUTIONS TO
KNOWLEDGE
• SD Optimization technique is universal in
application
• The versatility of SD as an Optimization tool has
been brought to fore in this paper
• Its flexibility in handling multi-parameters
simultaneously has equally been highlighted
I therefore recommend its usage to you all in your
various fields
37
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

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aquifer. Syst. Dynam. Rev. 15 (1999), 163–184.
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"The flexibility and versatility of System
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Sewer Effluents in NMAMIT, India"

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Sewer Effluents in NMAMIT, India"

40. A.N. Mashayekhi, Transition in New York State solid waste system: a
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New Delhi, 2012, p 30-36.
40
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"

41. THE END
41
"The flexibility and versatility of System
Dynamics technique in Optimization of
Sewer Effluents in NMAMIT, India"