FINAL YEAR PROJECT PRESENTATIONDesign of “Stormwater Drainage System of NUCES Lahore”

PROJECT GROUP MEMBERS▪ Rizwan Ahmed (L12-5769)

▪ Aenan Bashir (L12-5715)

▪ Muhammad Farooq Butt (L12-5776)

▪ Abdul Haseeb (L12-5802)

PROJECT TASKS▪ To design a stormwater drainage system for NUCES, Lahore

▪ System must be economical and sustainable in nature

WORK BREAKDOWN STRUCTUREPART-1

Reconnaissance Survey

Mapping of Project Area

Development of IDF Curves

Time of Concentratio

n

Calculate Surface Flow

DEVELOPMENT OF IDF CURVES▪ Rainfall data for years 1994 to 2014 was obtained from the Pakistan

Meteorological Department, Jail Road, Lahore.

▪ Data provided was “Highest rainfall in a day of a month”, giving 12 readings for an year

▪ Maximum rainfall in a day, was selected for each year.

▪ The data selected was, used to calculate rainfall intensity for durations for various periods.

RAINFALL DATA

Monthly Highest Rainfall in a DayYear Rainfall Year Rainfall Year Rainfall1990 83.1 2001 87 2012 76.4

1991 75.7 2002 29.4 2013 113.1

1992 69.6 2003 84.2 2014 177

1993 55.1 2004 58

1994 49.4 2005 136.8

1995 76.8 2006 114.6

1996 189.7 2007 49.4

1997 151 2008 80.7

1998 59 2009 49.4

1999 88.2 2010 122

2000 110 2011 86

Maximum Rainfall Recorded in Day, mm

INDIAN METEROLOGICAL FORMULA

Rainfall Intensity Calculation for Shorter Durations

Rainfall Intensity 83.1

Hours 1 2 3 6 12 18 24

Intensity 28.81 36.30 41.55 52.35 65.96 75.50 83.10

Selected Rainfall Intensity

Indian Meteorological Formula is used to convert the 24 hour Rainfall amount to shorter durations.

P is the precipitation, P(24) is the total amount of rainfall in 24 hours, t is the value of time in hours, for which we are calculating the precipitation. It is found that this formula provides best estimation of short duration rainfall.

CONVERSION OF WHOLE DATAConversion of Rainfall Data (1990-2014)

Years 1 Intensity 2 Intensity 3 Intensity 6 Intensity 12 Intensity 18 Intensity 24 Intensity1990 28.81 28.81 36.30 18.15 41.55 13.85 52.35 8.72 65.96 5.50 75.50 4.19 83.10 3.461991 26.24 26.24 33.07 16.53 37.85 12.62 47.69 7.95 60.08 5.01 68.78 3.82 75.70 3.151992 24.13 24.13 30.40 15.20 34.80 11.60 43.85 7.31 55.24 4.60 63.24 3.51 69.60 2.901993 19.10 19.10 24.07 12.03 27.55 9.18 34.71 5.79 43.73 3.64 50.06 2.78 55.10 2.301994 17.13 17.13 21.58 10.79 24.70 8.23 31.12 5.19 39.21 3.27 44.88 2.49 49.40 2.061995 26.63 26.63 33.55 16.77 38.40 12.80 48.38 8.06 60.96 5.08 69.78 3.88 76.80 3.201996 65.77 65.77 82.86 41.43 94.85 31.62 119.50 19.92 150.57 12.55 172.35 9.58 189.70 7.901997 52.35 52.35 65.96 32.98 75.50 25.17 95.12 15.85 119.85 9.99 137.19 7.62 151.00 6.291998 20.45 20.45 25.77 12.89 29.50 9.83 37.17 6.19 46.83 3.90 53.61 2.98 59.00 2.461999 30.58 30.58 38.53 19.26 44.10 14.70 55.56 9.26 70.00 5.83 80.14 4.45 88.20 3.682000 38.14 38.14 48.05 24.02 55.00 18.33 69.30 11.55 87.31 7.28 99.94 5.55 110.00 4.582001 30.16 30.16 38.00 19.00 43.50 14.50 54.81 9.13 69.05 5.75 79.04 4.39 87.00 3.632002 10.19 10.19 12.84 6.42 14.70 4.90 18.52 3.09 23.33 1.94 26.71 1.48 29.40 1.232003 29.19 29.19 36.78 18.39 42.10 14.03 53.04 8.84 66.83 5.57 76.50 4.25 84.20 3.512004 20.11 20.11 25.33 12.67 29.00 9.67 36.54 6.09 46.03 3.84 52.70 2.93 58.00 2.422005 47.43 47.43 59.75 29.88 68.40 22.80 86.18 14.36 108.58 9.05 124.29 6.91 136.80 5.702006 39.73 39.73 50.06 25.03 57.30 19.10 72.19 12.03 90.96 7.58 104.12 5.78 114.60 4.782007 17.13 17.13 21.58 10.79 24.70 8.23 31.12 5.19 39.21 3.27 44.88 2.49 49.40 2.062008 27.98 27.98 35.25 17.62 40.35 13.45 50.84 8.47 64.05 5.34 73.32 4.07 80.70 3.362009 17.13 17.13 21.58 10.79 24.70 8.23 31.12 5.19 39.21 3.27 44.88 2.49 49.40 2.062010 42.30 42.30 53.29 26.64 61.00 20.33 76.86 12.81 96.83 8.07 110.84 6.16 122.00 5.082011 29.81 29.81 37.56 18.78 43.00 14.33 54.18 9.03 68.26 5.69 78.14 4.34 86.00 3.582012 26.49 26.49 33.37 16.69 38.20 12.73 48.13 8.02 60.64 5.05 69.41 3.86 76.40 3.182013 39.21 39.21 49.40 24.70 56.55 18.85 71.25 11.87 89.77 7.48 102.76 5.71 113.10 4.712014 61.36 61.36 77.31 38.66 88.50 29.50 111.50 18.58 140.49 11.71 160.82 8.93 177.00 7.38Mean 31.50 31.50 39.69 19.84 45.43 15.14 57.24 9.54 72.12 6.01 82.56 4.59 90.86 3.79Stdev 13.97 8.80 6.71521 4.23 2.66 2.03 1.68

Amount of Rainfall in a day

Rainfall Intensity is calculated

Average and Standard Deviation of Rainfall Intensity for 24 hours

GUMBEL EXTREME VALUE TYPE 1

▪ Gumbel Extreme Value Type 1 was used to calculate rainfall intensity for return periods.

▪ Calculating “rainfall intensity for a certain frequency” (PT), following formula of Gumbel EVT-1 is used:

GUMBEL FREQUENCY FACTOR

▪ K is Gumbel frequency factor, given asT represents the “Return Period”. We have calculated K constant for 1.5, 2, 3, 5, 10, 20, 25, 30

GUMBEL EXTREME VALUE TYPE 1

▪ In order to calculating “rainfall intensity for a certain frequency” (PT), following formula of Gumbel EVT-1 is used:

Return Periods K 1-hour 2-hour 3-hour 6-hour 12-hour 18-hour 24-hour30 2.19 62.07 39.10 29.84 18.80 11.84 9.04 7.46

25 2.04 60.05 37.83 28.87 18.19 11.46 8.74 7.22

20 1.87 57.56 36.26 27.67 17.43 10.98 8.38 6.92

10 1.30 49.72 31.32 23.90 15.06 9.49 7.24 5.985 0.72 41.55 26.18 19.98 12.58 7.93 6.05 4.99

3 0.25 35.05 22.08 16.85 10.61 6.69 5.10 4.21

2 -0.16 29.21 18.40 14.04 8.85 5.57 4.25 3.51

1.5 -0.52 24.19 15.24 11.63 7.33 4.62 3.52 2.91

Avg 31.50 19.84 15.14 9.54 6.01 4.59 3.79

Standard Deviation 13.97 8.80 6.71521 4.23 2.66 2.03 1.68

INTENSITY DURATION FREQUENCY CURVES

0 5 10 15 20 25 300.00

10.00

20.00

30.00

40.00

50.00

60.00

70.00

Chart Title

30 Year Frequency 25 Year Frequency 20 Years Frequency15 Years Frequency 10 Year Frequency Curves 5 Year Frequency Curve

RUNOFF COEFFICIENT▪ The coefficient C is a dimensionless number that represent the fraction

of rainfall that appears as surface runoff in the drainage basin.

▪ If the rainfall becomes runoff, as it would be on the impervious surface, the value of C would be 1.0, it’s the maximum possible value.

▪ Factors that include the type of runoff coefficient include the type of land use in the drainage basin, the vegetation, and the ground slope.

TIME OF CONCENTRATION▪ There are two parts of the time of concentration, the overland flow

time and the channel flow time.

▪ The overland flow time is the time it takes the surface sheetflow to reach the beginning of the stream or storm drain inlet at the upper end of the basin.

▪ Several charts are also available that correlate the overland flow time with the ground slope with runoff coefficient.

▪ As the flow of stormwater in university is sheet flow, we have used the sheet flow formula by SCS to calculate time of concentration

TIME OF CONCENTRATION

▪ “Tc” is time of concentration in hours

▪ “n” is the manning roughness constant for the overland flow depth.

▪ “L” is the flow length.

▪ “P2” is the 2 year, 24 hour precipitation in inches.

▪ “S” is the slope of hydraulic grade line.

As the results are very small, resulting in very small time of concentration

RATIONAL METHOD▪ This the most popular formula that correlates with the runoff in

relatively small urban and suburban drainage basins is called “rational formula”.

▪ The rainfall formula expresses the relationship between peak runoff and rainfall formula as follows: Q = CIA

▪ It is important to note that Q in the rational formula represents only the maximum discharge caused by a particular storm.

CALCULATION OF FLOWCatchment Area C (Constant) Location Name Ground Type Intensity Area (m^2) Area (acre) Flow (m^3/hr) TC (Hours)

Area - 1 0.35 Sports Field Grass 0.04155 8347.26 2.06 121.39 0.06

Area - 2 0.80 Bike Parking Permeable Pavement, Brick 0.04155 1851.03 0.46 61.53 0.04

Area - 3 0.87 Civil Block Roof 0.04155 1925.47 0.48 69.60 0.04

Area - 4 0.80 Parking Area 1 Permeable Pavement, Brick 0.04155 1283.82 0.32 42.67 0.03

Area - 5 0.80 Parking Area 2 Permeable Pavement, Brick 0.04155 1707.32 0.42 56.75 0.04

Area - 6 0.87 Tennis Court Concrete Floor 0.04155 521.20 0.13 18.84 0.02

Area - 7 0.87 Basketball Court Concrete Floor 0.04155 696.80 0.17 25.19 0.03

Area - 8 0.90 Cafeteria Sloped Roof 0.04155 556.61 0.14 20.81 0.03

Area - 9 0.87 Library Roof 0.04155 865.30 0.21 31.28 0.03

Area - 10 0.80 Book Shop Parking

Permeable Pavement, Brick 0.04155 369.25 0.09 12.27 0.02

Area - 11 0.87 E&M Building Roof 0.04155 3153.28 0.78 113.99 0.04

Area - 12 0.80 Back Exit Permeable Pavement, Brick 0.04155 233.62 0.06 7.77 0.02

Area - 13 0.80 Parking Area 4 Permeable Pavement, Brick 0.04155 728.51 0.18 24.22 0.03

Area - 14 606.31

Rainfall Intensity selected from IDF Curves