The report for the subject of Water Disposal and Reuse

1. Wastewater Disposal and Reuse
Lab Report # 2
Design of the Disposal System
of Lahore
Muhammad Imran Nawaz
2008-ENV-43
26/03/2012

2. Table of Contents
Chapter 1
Introduction 2
Chapter 2
Preparation o model for existing conditions 4
2.1 Given Data for existing conditions 4
2.2 Constants and Velocities Given 4
2.3 Procedure for Developing the Model 5
2.4 Equations and Formulas used 5
2.5 Representation of the Results for Existing Conditions 6
Chapter 3
Treatment Options and Alternatives 8
3.1 Dilution 9
3.1.1 Applying Dilution to the Model 9
3.2 Treatment 11
3.3 Applying treatment options on the model 14
3.3.1 Trail 1: Using Primary Treatment 14
3.3.2 Trail 2: Applying 70 % DOT 16
3.3.3 Trail 3: Applying 80 % DOT 17
Chapter 4
Recommendations 19
References 20
1

3. Chapter 1
Introduction
For the section of the River Ravi from the entry point into Pakistan originating from India to
Ravi Siphon after Marala Ravi Link Canal joins, the river keeps a good water quality such as 2.8
to 4.3 mg/L in BOD5, 4.8 to 11.5 mg/L in COD, and 20 to 40 mg/L in SS. (EPA. Punjab Report)
Due to the discharge control at Thein Dam in India, the natural discharge from India is hardly
expected in the River Ravi especially during the dry season
Lahore is located in the upstream most reach of the Ravi River and all the domestic, commercial
and industrial wastewater generated in the almost entire Lahore with a population of 6.5 million
and 2,700 industries is discharged into the river without any treatment in 2008, which
substantially forms the biggest pollution source of its river basin.
At present, the major downstream use of the River Ravi is for irrigation beyond the
BallokiHeadworks. However, the population and economic activities in the immediate areas
along the river from Lahore to BallokiHeadworks (64 km) are affected in different degrees by
pollution in the river. It is estimated that waste water (domestic and industrial) from Lahore will
increase significantly as a proportion of total flow in the river. In a one in twenty year minimum
monthly flow, wastewater from Lahore accounted for about 47 percent of total flow in 1987,
rising to about 68 percent in 2007.(Source: Environment Department, CDGL, “Environmental
Profile of Lahore (2007-08)”
The wide variety of fish that once swam in the Ravi has vanished, as have the tiny minnows and
crabs children used to catch in the shallow waters along the banks. Even the reeds that used to
line the river have gone. The river is virtually dead even when the normally dry bed carries
water, such as after the rains.(Source: Environment Department, CDGL, “Environmental Profile
of Lahore (2007-08)”)
The Environmental Protection Department of the Punjab Provincial Government considers that
the river is under a constant threat of indiscriminate disposal of untreated municipal sewage from
Lahore / industrial sewage from Faisalabad through Maduana Drain and industrial effluent from
industrial units of Kala Shah Kaku along G.T. Road, Sheikhupura Road, Township and Gulberg
Industrial Estate located in Metropolitan of Lahore and untreated industrial wastewater of
District Kasur.(Source: Letter from the Secretary of EPD to the Secretaries of HUD&PHED,
Irrigation Department and Industrial Department, “Installation of Wastewater Treatment Plants
to Save River Ravi from Pollution”, dated 16/09/2009).
Historically, the River Ravi has not been used as a major source of potable water. Most
communities in the area, including Lahore, are dependent on ground water as the major source of
drinking water. In the rural areas of districts which border the river from Lahore to
2

4. BallokiHeadworks, only 0.3 percent of households are dependent on open surface watercourses
(river, springs and streams) for their drinking water. This represents about 1,700 households and
10,600 people. There are no known plants to use the River Ravi as a major water supply source.
(Source: Environment Department, CDGL, “Environmental Profile of Lahore (2007-08)”,
City of Lahore is discharging its wastes into the Ravi River through various outfalls over a given
length of the city which is polluting the river day by day which is a great threat for the aquatic
life and for the downstream uses of the river water. This report is aimed to construct a
mathematical model which will give the solution at different outfalls or which will give the
better alternatives for the disposal of wastewater. This model will give us the values of BOD and
the DO concentrations at each outfall for the existing conditions and for the proposed alternatives
which will be used to select the most appropriate method or the alternative for disposal. This
model is constructed to meet the DO requirements of 4 mg/l for the aquatic life.
Fig 1: location of different outfalls along the Ravi River with distances.
3

5. Chapter 2
Preparation of model for existing conditions
2.1 Given Data for existing conditions:
The data for flow, BOD and the DO is given below in the table for existing conditions along with
the distances of situation of outfalls. Flow (Q) is in m^3/S, BOD and COD in mg/L and the
distance is in meters.
Table 2.1: Given data for flow Q, DOD and DO along with the distances
Pumping Station Q (m^3/S) BOD (mg/L) DO(mg/L) Distance(Km)
Ravi Syphen 11.05 3 8 0
N.E PS 13.5 285 0 26.1
Shahdra 3.7 230 0 27.9
Main outfall 13.4 340 0 34.1
Gulshan Ravi 9 250 0 35.5
Multan Road PS 4.5 225 0 45.3
Hudiara Drain 11.11 130 2 60.3
Deg Drain 91.4 198 5 63
QB link Canal 544 5 8 85
Balloki head works 98.7
2.2 Constants and Velocities Given:
The value of constants like Ks, Kd and Kr and the velocities of the flow in the river are given in
the table below
Table 2.2: value of constants and Velocities in the river
Parameters m/s km/d
U(velocity upto Hudiara Drain m/s) 0.06 5.184
U (velocity after Hudiara Drain m/s) 0.27 23.328
mean Depth (m) 1.02
DO saturation mg/l 8
Kr (per Day) 0.5
Kd (per Day) 0.3
Ka(upto Hudiara Drain per Day) 0.9273
Ka(after Hudiara Drain per Day) 1.9671
4

6. 2.3 Procedure for Developing the Model:
All the given values and the given data is tabulated and arranged then BOD ultimate is
determined and then the mass balance of BOD is made at each and every outfall station and after
every 0.2 km distance. in the same way the mass balance of DO is made and the Deficit and the
DO values are determined at each outfall and after every 0.2 km distance.
After all this process the graph between the BOD and Distance and a graph between the DO and
the distance are plotted and which gives the proper representation of the existing conditions of
the Ravi river at different outfalls.
2.4 Equations and Formulas used:
For BOD model we use the general equation for 1st order reaction i.e.
The following Equation is used for Finding BOD Ultimate from BOD5 in mg/L
L = Lo(1 - 𝑒 −𝑘𝑡 ) ……………………………………2.4.1
And the following equation is used to find BOD ultimate for the river conditions
L = Lo 𝑒 −𝑘𝑡 ……………………………….………….2.4.2
The Equation given below is used to make the BOD Mass Balance at any outfall:
𝑄𝑟 𝑥 𝐶𝑟 + 𝑄 𝑒 𝑥 𝐶𝑒
Concentration (mg / L) = ……………….………….2.4.3
𝑄𝑟 +𝑄𝑒
and
the following Equation is used to find the Deficit for finding DO Concentration in river:
𝑋 𝑋 𝑋
𝐾𝑑 𝐿𝑜
Dx = (𝑒 −𝐾𝑟 𝑈 -𝑒 −𝐾𝑎 𝑈 ) + Do (𝑒 −𝐾𝑎 𝑈 ) …………………..2.4.4
𝐾𝑎 −𝐾𝑟
First of all the equation 2.4.1 is used to find out BODu from the given BOD5 then a mass
balance is made using the equation 2.4.3 at the first outfall for BOD, after that point the equation
2.4.2 is used to find out the BOD at different points from one outfall to the next with a distance
increment of 0.2 km. the equation 2.4.4 is used to find out the deficit for determining the DO
values.
5

7. 2.5 Representation of the Results for Existing Conditions:
After making the mass balance and all of the above calculations the findings of the results are
made which includes the representation of whole of the data. Below is the table which represents
the results of the model for present or existing conditions.
Table 2.3: Results generated the model for EXISTING CONDITIONS:
DO
Pumping accumulative mass Distance
Stations Q Flow BOD (mg/L) DO Balance deficit (Km)
Mass
(m^3/S) (m^3/S) BOD5 BOD u Balance mg/L mg/L
Ravi Syphen 11.05 11.05 3 3.27 8 0
N.E PS 13.5 24.55 285 310.49 172.21 0 3.60 4.40 26.1
Shahdra 3.7 28.25 230 250.57 158.62 0 0 8 27.9
Main outfall 13.4 41.65 340 370.40 178.33 0 0 8 34.1
Gulshan Ravi 9 50.65 250 272.36 176.52 0 0 8 35.5
Multan Rd PS 4.5 55.15 225 245.12 83.00 0 0 8 45.3
Hudiara Drain 11.11 66.26 130 141.63 40.00 2 4.63 3.37 60.3
Deg Drain 91.4 157.66 198 215.71 140.95 5 4.84 3.16 63
QB link Canal 544 701.66 5 5.45 23.99 8 6.87 1.13 85
Balloki Drain 98.7
The graphical representation of the above results is shown below in the form of BOD and DO at
different outfalls
Graph 2.1: BOD Profile for Existing Conditions
200
BOD Vs Distance
180
160
140
BOD(mg/L)
120
100
80
60
40
20
0
20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Distance (KM)
6

8. Graph 2.2: DO Profile for Existing Conditions
8
DO profile
7
6
5
DO (mg/l)
4
3
2
1
0
20 30 40 50 60 70 80 90 100
Distance (KM)
The existing condition shown in the above graphs gives very worst conditions. The BOD values
are very high that are frequently more than the NEQS values that is 80 mg/L that represents the
unacceptable conditions for the aquatic life and for the downstream use of river water.
The DO values are also lower than the NEQS standard values for the aquatic life of 4 mg/L in
most of the places like from NE pumping station to the mid of the Multan Rd Pumping station
the valves are below zero because the initial values of DO are also zero at these points, the
effluent DO is zero. These are also worst conditions for the aquatic life to survive in this
environment. These values should be greater than or equal to the NEQS of 4 mg/L otherwise the
existence of aquatic life will be impossible. These scenarios make the Ravi River as DEAD
River.
7

9. Chapter 3
Treatment Options and Alternatives
Treatment or any other alternatives are required for the worst conditions of the River Rave for its
proper water use and to prevent aquatic life. A lot of work is done and also is being done on the
River Rave to improve its existing conditions. A brief summary of these works is given below to
have an idea about the projects that are proposed for the River.
WASA Lahore is responsible for maintaining the water supply sewerage and storm water
drainage system for city of Lahore. The construction of piped water supply system started in
Lahore in 1870 in and around the Walled City of Lahore, whereas sewerage system was
introduced in the central part of the city in 1936-37, mostly in the shape of brick sewers.
Sewerage system in the Central areas of the Lahore started more than 70 years ago. Most of the
system has outlived its life and need replacement. During this period there has been an immense
increase in population, making the system in adequate and under sized.
To address these problems Economic Affair Division (EAD), Government of Pakistan sent
official request to the Government of Japan in July 2008 for loan assistance to
(a) Lahore South East Sewerage Treatment Project and
(b) Lahore Sewerage and Storm Drainage Improvement Project, and another official request
was sent from EAD in September 2008 on technical assistance on
(c) Study/ review of Comprehensive Sewerage and Drainage System in Lahore and
(d) Study for Water Distribution System of Lahore City.
Given the high priority of the Government of Pakistan on Water Supply, Sewerage and Drainage
Improvement in Lahore, JICA(Japan International Cooperation Agency) decided to start “The
Preparatory Study on Lahore Water Supply, Sewerage and Drainage Improvement Project”, The
Study aims to formulate the Project which may be financed by JICA’s loan assistance. The Study
was started in March 2009 and completed by July 2010. The Study aimed to formulate “the
Lahore Water Supply, Sewerage and Drainage Improvement Project” through basic study,
review of vision and strategy on development and management of water supply, sewerage, and
drainage facilities in Lahore and based on this study, preparation of the project plan and of plan
for implementation, operation and maintenance, confirmation of environment, social
considerations, thereby improving efficiency of water supply, improving sanitary environment
and water quality in public water bodies, alleviating flooding and improving management
capacity.
Meanwhile, a renewed official request with eight projects including this Project was submitted
from EAD to the Government of Japan in September 2009. JICA’s Fact Finding Mission (“F/F
8

10. Mission”) aimed to confirm the progress of the important institutional improvement action
agendas, which were agreed to be progressed by appraisal mission between Pakistani side
(WASA, HUD&PHED, and P&D) and JICA agreed in the previous F/F Mission, and to carry out
fact-finding for the Project. The Pakistani side and the JICA Mission agreed to take necessary
actions on the basis of the framework agreed in this Minutes of Discussion.
A meeting was held between Pakistani Mission and JICA Mission on December 9, 2010 and in
this meeting the JICA Mission strongly requested the Pakistani side to get the PC-I approval
from CDWP by the timing of Pledge (Prior-notification) from Government of Japan to
Government of Pakistan in the same way as past JICA-financed projects. Accordingly this PC-I
has been prepared and submitted to government for approval.
Treatment options and Alternatives:
To maintain the river water in favorable conditions or to avoid the worst conditions like the
existing ones, two options can be done
 Dilution
 Treatment
1. Dilution
Dilution is a reduction in the concentration of the chemical or the waste loads in the river usually
by adding or mixing with more liquid/water in the river flows. In this way the waste loads can be
reduced to larger limits. In dilution we add water into the river flows allowing it to mix the
wastes thoroughly which reduces their concentration.
Dilution can be done from the initial point i.e. adding a maximum amount of water to the river or
it can also be done at the different outfalls by adding water in larger quantities to reduce the
waste concentrations.
Applying Dilution to the Model
Now we will apply the dilution to our model, for this we will require a larger amount of water to
dilute the river flow, for this we will also have to make dilution to each of the outfall for
improving the DO levels. We will consider a DO value of 3 mg/l at each of the outfall and an
initial dilution is made four times of the existing flow at Ravi Syphen and also adding a dilution
of 2 m^3/S at each outfall, we will have these results.
9

11. Table 3.1: Results generated the model for DILUTION
Addition acc. DO mass Distance
Pumping St. Q of Flow Flow BOD (mg/L) DO Balance deficit (Km)
Mass
m^3/s (m^3/S) (m^3/S) BOD5 BOD u Balance mg/L mg/L
Ravi Syphen 45 2 47 3 3.27 8 0
N.E PS 13.5 2 62.5 285 310.49 69.42 3 6.41 1.59 26.1
Shahdra 3.7 2 68.2 230 250.57 67.07 3 2.084892 5.91511 27.9
Main outfall 13.4 2 83.6 340 370.40 89.46 3 0.767053 7.23295 34.1
Gulshan Ravi 9 2 94.6 250 272.36 94.98 3 0.285412 7.71459 35.5
Multan Rd PS 4.5 2 101.1 225 245.12 45.45 3 1.146964 6.85304 45.3
Hudiara Drain 11.11 2 114.21 130 141.63 23.24 3 5.85 2.15 60.3
Deg Drain 91.4 2 207.61 198 215.71 107.06 5 5.43 2.57 63
QB link Canal 544 751.61 5 5.45 22.40 8 6.92 1.08 85
Balloki Drain 98.7
Graph 3.1: BOD Profile for DILUTION Conditions
BOD Vs Distance
120
100
80
BOD
60
40
20
0
20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Distance (KM)
10

12. Graph 3.2: DO Profile for DILUTION Conditions
DO Profile
8
7
6
5
DO (mg/l)
4
3
2
1
0
20 30 40 50 60 70 80 90 100
Distance (KM)
Findings for Trail 1 of Dilution:
For increasing the initial flow to four times of the existing and adding a flow of 2 m^3/S at each
outfall in the river as dilution makes the river conditioned for BOD as satisfactory that is , the
BOD is almost reached the NEQS of 80 mg/l at most of the outfalls,
But for DO the results are still not acceptable even we have added the initial DO of 3 mg/l at
each outfall but the results are not meeting the NEQS
Now we will have to install any treatment facility for the outfalls to reduce their BOD levels to
acceptable limits, by installing the treatment facilities we will have better conditions for both
BOD and the DO even without increasing the flow or making any dilution.
2. Treatment
Sewage treatment, or domestic wastewater treatment, is the process of removing contaminants
from wastewater and household sewage, both runoff (effluents) and domestic. It includes
physical, chemical, and biological processes to remove physical, chemical and biological
contaminants. Its objective is to produce an environmentally-safe fluid waste stream (or treated
effluent) and a solid waste (or treated sludge) suitable for disposal or reuse (usually as farm
fertilizer). Using advanced technology it is now possible to re-use sewage effluent for drinking
water, although Singapore is the only country to implement such technology.
11

13. There are different methods, techniques and processes to treat the wastewate that are used now
days. Some of them are listed and a brief description is given below that are mainly and
frequently used.
 Activated sludge process
 Aerated lagoons
 Trickling Filters
 Waste Stabilization Ponds
 And many others
I. Activated sludge process
The most common suspended growth process used for municipal wastewater treatment is the
activated sludge process.
Activated sludge plant involves:
1. wastewater aeration in the presence of a microbial suspension,
2. solid-liquid separation following aeration,
3. discharge of clarified effluent,
4. wasting of excess biomass, and
5. return of remaining biomass to the aeration tank.
In activated sludge process wastewater containing organic matter is aerated in an aeration basin in
which micro-organisms metabolize the suspended and soluble organic matter. Part of organic matter
is synthesized into new cells and part is oxidized to CO2 and water to derive energy. In activated
sludge systems the new cells formed in the reaction are removed from the liquid stream in the form of
a flocculent sludge in settling tanks. A part of this settled biomass, described as activated sludge is
returned to the aeration tank and the remaining forms waste or excess sludge.
II. Aerated lagoon
Aerated lagoons are relatively shallow lagoons in which wastewater is added at a single point
either at the edge or middle of the lagoon and the effluent is removed from another point. The
retention time is a function of the percent removal of BOD. The retention time may vary from 6
to 18 days as the removal of BOD from domestic wastewater varies from 75 to 90 percent.
Oxygen is supplied by means of surface aerators or by diffused aeration units. The action of the
aerators also maintains the solids of the lagoon in suspension. Depending on the degree of
mixing, lagoons may be operated as either aerobic or as aerobic-anaerobic systems.
12

14. In aerobic lagoons all biological solids are in continual suspension and stabilization of the
rganics occurs under aerobic conditions. In the case of the aerobic-anaerobic lagoon a large
portion of the solids settles to the bottom of the lagoon. As the solids build up, a portion will
undergo anaerobic decomposition. Therefore, stabilization in this case occurs partly under
aerobic conditions and partially in anaerobic conditions
III. Trickling filter
A trickling filter consists of a fixed bed of rocks, lava, coke, gravel, slag, polyurethane foam,
sphagnum peat moss, ceramic, or plastic media over which sewage or other wastewater flows
downward and causes a layer of microbial slime (biofilm) to grow, covering the bed of media.
Aerobic conditions are maintained by splashing, diffusion, and either by forced air flowing
through the bed or natural convection of air if the filter medium is porous.
The terms trickle filter, trickling biofilter, biofilter, biological filter and biological trickling filter
are often used to refer to a trickling filter. These systems have also been described as roughing
filters, intermittent filters, packed media bed filters, alternative septic systems, percolating filters,
attached growth processes, and fixed film processes.
IV. Stabilization Ponds
A stabilization pond or "oxidation pond" as it is often called, is usually a shallow earthen basin
of controlled shape, which is designed for treating wastewaters from small communities or
industrial plants. The ponds are usually 2 to 4 feet deep, although much deeper ponds have been
used quite successfully. Stabilization ponds have been applied singly as part of a treatment
scheme or as the sole process, providing complete treatment.
The process involves two major steps in the decomposition of organic matter in wastewater. The
carbonaceous matter is first oxidized by the aerobic microorganisms with the formation of
carbon dioxide and the inorganic forms of nitrogen and phosphorous. These inorganic forms are
then used by algae in their photosynthetic reactions. Photosynthesis is a natural process carried
on by green plants in the presence of light. One of the end products of photosynthesis is oxygen
which becomes available to the aerobic microorganisms. As a result of the reactions in the
ponds, the organics in wastewater are partly oxidized and partly converted to algae cells. Algae
has been harvested in some of the locations and used for animal feed as a protein source.
Therefore, treatment of wastewater with the production of a useful by-product is possible in
stabilization ponds.
Most stabilization ponds are designed for loadings of one acre per 400 persons, 50 pounds of
BOD per acre per day or 15 pounds of BOD per acre foot per day with detention periods
generally greater than 30 days. The natural soil in which they are located should be fairly
13

15. impervious so that seepage will not materially affect the surface level of the wastewater in the
pond.
These ponds are low cost in construction and require a minimum of operation. The requirement
that large, fairly isolated areas be provided limits their use to relatively small populations in areas
where land is available.
Using the model and applying treatment:
Using any of the process for the outfalls the value of BOD is decreased to a maximum level and
then the wastewater is disposed off into the river. Using these processes for treatment we will
now use the reduced BOD values for our model and will predict the downstream concentration
levels and we will later on use any of these options to treat the river water for acceptable values
of the BOD and that of DO.
Trail 1: Using Primary Treatment
Using the trail 1 that is to treat the wastewater at each outfall to the primary level that is DOT
degree of treatment is 40 % and maintaining the initial DO level to 5 mg/l at each outfall.
Table 3.2: Results generated the model for PRIMARY TREATMENT (TRAIL 1)
DO
Pumping mass Distance
Stations Q Acc Flow BOD (mg/L) DO Balance deficit (Km)
Mass
(m^3/S) (m^3/S) BOD5 BOD u Balance mg/L mg/l
Ravi Syphen 11.05 11.05 3 3.27 8 0
N.E PS 13.5 24.55 171 186.29 103.91 5 6.350 1.650 26.1
Shahdra 3.7 28.25 138 150.34 95.60 5 0.655 7.345 27.9
Main outfall 13.4 41.65 204 222.24 107.16 5 1.609 6.391 34.1
Gulshan Ravi 9 50.65 150 163.41 106.03 5 0.888 7.112 35.5
Multan Rd PS 4.5 55.15 135 147.07 49.84 5 0.903 7.097 45.3
Hudiara Drain 11.11 66.26 78 84.98 24.01 5 5.949 2.051 60.3
Deg Drain 91.4 157.66 118.8 129.42 84.57 5 5.398 2.602 63
QB link Canal 544 701.66 5 5.45 16.08 8 7.254 0.746 85
Balloki Drain 98.7
14

16. Graph 3.3: BOD Profile for PIMARY TREATMENT (TRAIL 1)
120
BOD Vs Distance
100
80
BOD(mg/L)
60
40
20
0
20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Distance (KM)
Graph 3.4: DO Profile for PIMARY TREATMENT (TRAIL 1)
DO Profile
8
7
6
5
DO (mg/l)
4
3
2
1
0
20 30 40 50 60 70 80 90 100
Distance (KM)
The above results shows that applying the primary treatment with 40 % DOT the BOD removal
is very much significant but the DO value are still not meeting the required standards of 4 mg/l
although applying the initial DO values of 5 mg/l at each outfall.
This trail is not acceptable for DO values so we will take another trail.
15

17. Trail 2: Applying 70 % DOT
Using the trail 2 that is to treat the wastewater at each outfall to the DOT degree of treatment of
70 % and maintaining the initial DO level to 5 mg/l at each outfall.
Table 3.3: Results generated the model for DOT OF 70 % (TRAIL 2)
Pumping DO mass Distance
Stations Q Acc Flow BOD (mg/L) DO Balance Deficit (Km)
Mass
(m^3/S) (m^3/S) BOD5 BOD u Balance mg/L mg/l
Ravi Syphen 11.05 11.05 3 3.27 8 0
N.E PS 13.5 24.55 85.5 93.15 52.69 0 3.601 4.399 26.1
Shahdra 3.7 28.25 69 75.17 48.34 0 1.049 6.951 27.9
Main outfall 13.4 41.65 102 111.12 53.78 0 1.086 6.914 34.1
Gulshan Ravi 9 50.65 75 81.71 53.16 0 0.000 8.000 35.5
Multan Rd PS 4.5 55.15 67.5 73.54 24.97 0 3.206 4.794 45.3
Hudiara Drain 11.11 66.26 39 42.49 12.02 2 6.148 1.852 60.3
Deg Drain 91.4 157.66 59.4 64.71 42.29 5 5.516 2.484 63
QB link Canal 544 701.66 5 5.45 10.15 8 7.516 0.484 85
Balloki Drain 98.7
Graph 3.5: BOD Profile for DOT OF 70 % (TRAIL 2)
60
BOD Vs Distance
50
40
BOD(mg/L)
30
20
10
0
20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Distance (KM)
16

18. Graph 3.6: DO Profile for DOT OF 70 % (TRAIL 2)
9
DO Profile
8
7
6
DO (mg/l)
5
4
3
2
1
0
20 30 40 50 60 70 80 90 100
Distance (KM)
The above results shows that applying the secondary treatment with 70 % DOT the BOD
concentration in the river is now in the standard values but the DO value are still not meeting the
required standards of 4 mg/l in the start at starting outfalls, although applying the initial DO
values of 5 mg/l at each outfall. This trail is not acceptable for DO, we will take another trail
Trail 3: Applying 80 % DOT
Using the trail 3 that is to treat the wastewater at each outfall to the DOT degree of treatment of
80 % and maintaining the initial DO level to 5 mg/l at each outfall.
Table 3.4: Results generated the model for DOT OF 70 % (TRAIL 2)
DO
Pumping mass Distance
Stations Q Acc Flow BOD (mg/L) DO Balance deficit (Km)
(m^3/S) (m^3/S) BOD5 BOD u Mass Balance mg/L mg/l
Ravi Syphen 11.5 11.5 3 3.27 8 0
N.E PS 13.5 25 57 62.097 35.036 5 6.380 1.620 26.1
Shahdra 3.7 28.7 46 50.114 32.116 5 4.503 3.497 27.9
Main outfall 13.4 42.1 68 74.081 35.619 5 4.399 3.601 34.1
Gulshan Ravi 9 51.1 50 54.471 35.233 5 3.448 4.552 35.5
Multan Rd PS 4.5 55.6 45 49.024 16.551 5 5.130 2.870 45.3
Hudiara Drain 11.11 66.71 26 28.325 7.964 5 6.956 1.044 60.3
Deg Drain 91.4 158.11 39.6 43.141 28.117 5 5.840 2.160 63
QB link Canal 544 702.11 5 5.447 8.172 8 7.630 0.370 85
17

19. Graph 3.7: BOD Profile for DOT OF 80 % (TRAIL 3)
40
BOD Vs Distance
35
30
25
BOD(mg/L)
20
15
10
5
0
20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Distance (KM)
Graph 3.8: DO Profile for DOT OF 80 % (TRAIL 3)
DO Profile
9
8
7
6
DO (mg/l)
5
4
3
2
1
0
20 30 40 50 60 70 80 90 100
Distance (KM)
The trail 3 is somehow very reasonable trail also for the DO concentration that most of the times
meet the standards and the BOD is completely within the standard.
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20. Chapter 4:
Recommendations
Lahore is a main city of Pakistan and which is recognized internationally and it should have the
basic facilities of road infrastructure, sanitation, clean drinking water and sewerage. This
crowded city generates a huge amount of the waste produced daily now it is the need to properly
dispose it off, for this different treatment plants at different outfalls are running in spite of this
the Ravi river is going polluted day by day, because the condition of these treatment plants is
worth seeing, and also due to the direct disposal of waste to the River without any treatment.
Now the need is to properly handle the waste produced and dispose it off.
At source treatment:
We can control the worst conditions of the Ravi River by individual awareness; each and every
individual citizen of the city can play its role,
Every house of any community of a colony should have a septic tank instead of disposing the
waste directly to the sewers and they can also make dilution to the waste, this will reduce the
BOD concentrations to a very low values so the treatment starts from the point of generation of
the waste, this awareness should be created to the public so that the worst conditions of the
disposal of the wastewater in Lahore can be controlled.
Making a collector Drain along the River:
If a collector drain is made all along the Ravi River so that it will collect all of the wastewater
from all of the outfalls and will eventually dispose it to the end of the city at Baloki Head Works
where a lot of dilution to the river is available, or at that point a treatment plant should be
installed which will treat the wastewater before disposing it into the Ravi River.
If this collector channel is made all along the River Ravi then the River water will be pure all
along the city and all the recreational facilities like fishing and boating can be made alive, and
also the aquatic life will sustain in that environment which will be an healthy activity.
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21. References:
 Environment Department, CDGL, “Environmental Profile of Lahore (2007-08)”
 EPA. Punjab Report
 http://water.me.vccs.edu/courses/ENV149/stabilization.htm
 http://nptel.iitm.ac.in/courses/Webcourse-contents/IIT-
KANPUR/wasteWater/Lecture%2024.htm
 http://nptel.iitm.ac.in/courses/Webcourse-contents/IIT-
KANPUR/wasteWater/Lecture%2024.htm
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