1. An-najah National University Faculty of Engineering
Evaluation of the Existing situation
of the sewer system of Qalqilia city
And design of the northern part of the city
By:
Hedaia Adnan Shawahna –Reg.No:
Maram Mahmoud Qaisiah-Reg No:
Under supervision of: Eng Hamees Tubeileh

2. Outline:- INTRODUCTION Objectives Approach and methodology
Evaluation of the existing network
Modeling and Design
Result and Disscussion
Conclosion and Recomondation

3. Qalqilya is surrounded on all sides by Israel's separation barrier.
INTRODUCTION
Study Area
Location:
Qalqilya is located in the northwest of the West Bank about 12 km from the Mediterranean coast, on the border between Israel and the West Bank.
and at latitude 32.2 northwith area of 7.25Km2.
Qalqilya is surrounded on all sides by Israel's separation barrier.

5. Climate:
Qalqilia, like all parts of Palestine climate has Mediterranean slant moderate heat in summer to cold winter. The average annual temperature of 18.9 C .
The average maximum temperature of 22.3 C, and the average minimum temperature of 15.6 Celsius.
The humidity is relatively high compared with the mountainous regions and cities of the interior, where the annual average of the year to about 70%.

6. Topography:
Qalqilya rising from the sea about 40 meters in the western plains region , and begin to rise gradually to the east to reach the 120 meters at the top of the area,our study area (the north region elevation range (105-55) m.

7. Contour Map for north of Qalqilia City

8. Population and water demand:
Qalqilia city has one of the highest rates of population growth in Palestine in recent decades .This is due to the migration of thousands of residents of nearby villages after the catastrophe of 1948.Now with 48000people, and 8500 house connections have a present demand of clean water, which exceeds 4.0 MCM/yr, i.e. 200 l/c/d.

9. Problem Statement
Most of Qalqilia city is served by sewer network. The northern area of Qalqilia has a normal urban expansion. At the current situation there is only few houses in this area and they are connected with small pipe diameters. The sewer system was designed in the Intifada period there was no sufficient financial resources to meet the amount of sewer. So the existing sewer pipes in the northern part can't handle the future load.

10. Objectives
So it is very important to solve the problems of enclosing the pipes that carry the sewer water and flooding due to the rain fall and this can be achieved by:
Evaluation the existing situation of the sewer system in Qalqilia city.
Analysis and design the sewer network for the northern part of this city.

11. Approach and methodology

12. Evaluation of the existing:
Wastewater Catchments
The served area of Qalqilia city is divided into two main sewage collection catchment areas. These are Southern Wadi catchment and Old Wadi catchment which combines by pumping the other two sub-catchments of the northern Qalqilia city. Both of these catchments have their own outfall to the west of Qalqilia city.

13. Southern Wadi catchment
The Southern Wadi catchment forms 37% of Qalqilia city. Most of the future urban development is expected to take place within this catchment due to the fact that land parcels are available and are suitable for urban development. The total population served by this catchment is about 13,900 inhabitants and 2300 households.
In General, the sewage network in this catchment is new. The sewer network was designed based on acceptable engineering standards and guidelines. The total length of the sewage network in this catchment is 36.6 km compromise of one trunk line, four main lines, nine sub-mains and several laterals. The number of manholes within this catchment is 1932.

14. Old Wadi Catchment
The sewage network in the Old Wadi catchment was developed in two stages; the old sewage network that mostly serves Qalqilia old city and the new sewage network that was constructed recently. The Old Wadi catchment consists of three sub-catchments; one completely drains by gravity to the outfall and the other two sub-catchments ends up by pumping stations. The two force mains from the pumping stations drain to the gravity network in the Old Wadi catchment and drains at the same outfall west of Qalqilia city. The Old Wadi catchment covers 63% of Qalqilia city. This area has limitations regarding the horizontal urban expansion due to the lack of land, the Israeli segregation wall, and the present population congestion. The total population served in the Old Wadi catchment is 33,500 inhabitants. The total length of the sewage network in this catchment is 68.5 km of sewage pipes consisting of concrete, plastic and steel (force mains). The number of manholes in the catchment is 4789.

15. Northern Pumping Station
The two pumps located within the Old Wadi catchment are:
Northern Pumping Station
This pumping station serves the sub-catchment located in the north east of Qalqilia city called Hai Al Kur’an and the surrounding neighborhood. This sub-catchment is part of the Old Wadi catchment where it shares the same outfall, but pumps to the western pumping station, from where the wastewater is further pumped to the Old Wadi network. The total population that is served by this pumping station is 4812 inhabitants. The area for the sub-catchment is 20% of the total area of the Old Wadi catchment.

16. Western Pumping Station
The sub-catchment served by this pumping station is part of the Old Wadi catchment. The force main of the northern pumping station is connecting the sub-catchment to the gravity network of the western pumping station, which then pump both wastewaters to the same final outfall. The western pumping station is serving 11,737 inhabitants (including the catchment of the northern pumping station). It covers 47% of the total area of the Old Wadi catchment serving 6925 inhabitants in addition to the 4812 inhabitants of the northern pumping station.

17. Manholes: - Cover diameter ranges from 35 to 65 cm in diameter
- Most of the cover duty class is of the 8 ton class; others range from 5 ton to 40 tons duty class.
- 70% of the manholes are located on paved roads while 25% are located on sidewalks and the remaining 5% are located on dirt and/or agricultural roads.
- Adjustment is needed for some 1400 manholes, i.e. about 20% of the manholes. This is a high ratio. .

18. - 92% of the manholes covers are in good conditions while the remaining manhole covers are either in fair or bad conditions. -about 64% of manholes are in good conditions. - Sediments and crack are the main parameters and findings. - Some manholes are collapsed and need immediate replacement.

19. Pipelines
Qalqilia city sewage collection system consists predominantly of gravity sewers. These gravity sewers vary in diameter, material type, depth, and year built. It consists of gravity sewage collection pipes, two pumping station, two main outfall, and two small pumps submerged inside manholes. The diameter of the pipes various from 4 inch up to 20 inches at the outfall. Qalqilia network have two types of material which are uPVC and concrete. The concrete pipes represent the old sewage collection network, while uPVC pipes were used in the recently constructed network sections. As reported by Qalqilia municipality, there are more than one sewage pipes constructed in the right of way.

20. In Qalqilia sewage network, there are varieties in the pipe diameter; 58% of the network pipes are classified as laterals and most of the diameters are 6" and 8". The two interceptors that extend to the outfalls are 14" for the southern Wadi catchment, and 18" for the Old Wadi catchment. Table 2.1 is a summary of the pipe diameter of Qalqilia city sewage network.

21. The material of the sewage pipes are concrete and uPVC
The material of the sewage pipes are concrete and uPVC. The concrete pipes are 11.42% of the total length for Qalqilia sewage collection network. In general most the concrete pipes are in bad condition specially the pipes that are less than 8 inches. The uPVC pipe varies from 4" up to 18". For concrete pipes there are 4", 6", 8", 10", 12" and 20".

22. Data collection Road network and houses distribution map. Contour map
Consumption
Population
Existing sewer network

25. Pfuture = Ppresent (1+i)n
The present number of population in Qalqilia city is about Capita.
To find the future population use:
Pfuture = Ppresent (1+i)n
Pfuture =population in the future at year n (person).
Ppresent=population at present year (person).
i = growth rate. Which is used as 3.12% for Qalqilia city.
n = design year (year).

26. The average consumption of water for Qalqilia is taken as 206 l/c
The average consumption of water for Qalqilia is taken as 206 l/c.d according to the municipality records

28. MODELING AND DESIGN Sewer CAD:
Engineers around the world use Sewer CAD to plan, design, analyze, and optimize their wastewater collection systems. An easy-to-use interface, automatic design features, and stunning presentation tools.
It gives the possibility of export to AutoCAD, Excel, GIS also to import from them.
The program provides organized and summarized tables which give comfortable to input data and take it from those tables.

29. Input data
1) AutoCAD road layout in the form of DXF file

30. 2) Manhole location layout
3) Related elevation of each manhole taken as AutoCAD contour map using TREX

31. 4)Count of capita per each manhole as EXCEL sheet using Model Builder.

33. 5) Unit sanitary load.
To determine the total load on manhole we do the following:
The per capita total load on manhole will become from the wastewater generated by using water and from infiltration. The calculation of this unit load was as follow:
a. By taking the average consumption of water from municipality it was be 206 l/c.d .the conversion factor from water to wastewater was taken 75%, and the maximum hourly factor was assumed to be 3.
b. The average daily per capita wastewater generation amount equals (206*0.75) in L/d.
c. By multiplying by 3 having maximum hourly wastewater generated load .
d .to take into consideration the amount of infiltration multiplying by 20%.

34. 2 .By assuming the saturation condition will be when having building of three floors with two departments per floor.
3. Counting the number of houses at saturation condition that can be connected to the adjacent manhole.
4. Determining the population that generates the sanitary load for each manhole by multiplying the size of family (taken as 6) by number of building by number of department for each floor.
5. The load on each manhole will equal the capita total load multiplied by the number of population that generates this load at this manhole.

35. example for one manhole
Unit load=206 *0.75*3+0.2*206*0.75=
494.4 L/d.
Take it=495 L/d.
At manhole #377 we have 3 buildings ,considering 3 floors and 2 departments and 6 persons for each one
(3*3*2*6)*=108 Capita Present

37. Output: Label Elevation (m) Flow in (L/s) Flow Out (L/s)
Total load(m/s)
unit count(capita)
MH-1
87.8
2.04
2.45
0.41
90.5
MH-2
87.75
1.63
MH-3
88.42
1.23
0.4
MH-4
89.02
0.82
MH-5
88.2
MH-6
88.06
MH-7
82.4
2.86
3.27
MH-8
81.92
MH-9
81.58
MH-10
81.77
MH-11
82.3
MH-12
82.71 .

38. Outputs: Label Start Node Stop Node Length (m) Slope (%) Diameter (in)
Velocity (m/s)
CO-1
MH-6
MH-5
31.8
1.477
3.9
0.45
CO-2
MH-4
27.4 1
0.48
CO-3
MH-3
33.1
0.54
CO-4
MH-2
30.5
0.58
CO-5
MH-1
0.62
CO-6
MH-116
26.4
0.65
CO-7
MH-117 33
0.67
CO-8
MH-118
27.7
1.581
0.83
CO-9
MH-119
37.4
0.71
CO-10
MH-120
40.3
3.278
1.15
CO-11
MH-121
37.8
7.807
1.62
CO-12
MH-13
MH-12 32
1.126
0.5
CO-13
MH-11
28.5
1.467
Label
Start Node
Stop Node
Length (m)
Slope (%)
Diameter (in)
Velocity (m/s)
CO-1
MH-6
MH-5
31.8
1.477
3.9
0.45
CO-2
MH-4
27.4 1
0.48
CO-3
MH-3
33.1
0.54
CO-4
MH-2
30.5
0.58
CO-5
MH-1
0.62
CO-6
MH-116
26.4
0.65
CO-7
MH-117 33
0.67
CO-8
MH-118
27.7
1.581
0.83
CO-9
MH-119
37.4
0.71
CO-10
MH-120
40.3
3.278
1.15
CO-11
MH-121
37.8
7.807
1.62
CO-12
MH-13
MH-12 32
1.126
0.5
CO-13
MH-11
28.5
1.467

39. EGL&HGL

40. Results: 143 Number of manholes 3.77 Maximum velocity(m/s) 0.45
Minimum velocity(m/s)
5.59
Maximum cover(m) 1
Minimum cover(m)
Minimum slope(%) 15
Maximum slope(%)
CONDIUTE TABLE
DIAMETER(in)
LENGTH(m) 4
2721.5 6
312 8
31.5 10
473 12
595.5 .

41. this figure shows the variety of cover along the conduits, by using scattered plots we represent this profile. This representation show the deviation of the cover from the minimum and the maximum constrains

42. Results of velocity in conduit show that all conduits velocities satisfy minimum velocity criteria except the manhole that we put it for maintenance (having no load on it). There's 4.35% of conduit having velocity exceed the maximum limitation We can make reduction in these values by enlarging the diameters of the conduits.

43. Conduits table provides the slopes of the sewers
Conduits table provides the slopes of the sewers.to make our conclusion of the slope constrains we represent the slope for each conduit to show the maximum and minimum values (see figure4.4).

44. Conclosion &Recomondation
Based on the evaluation of the existing situation of the wastewater network, the following recommendations are worth mentioning:
1. The Northern pumping station is causing problems in terms of high operation and maintenance costs and is considered burden on the sewage network. It pumps the sewage to the Western pumping station to be pumped again to the Old catchment system. It is recommended to allow the sewage to flow and form another outfall at its downstream end and then stop the northern pumping station.

45. 2. The stopping of the northern pumping and even western pumping station will require considering additional outfalls at the Israeli segregation wall. 3. The present pumping stations will be overloaded in 10 years or less, which shall be considered in the future planning alternatives.

46. 4. Another alternative to be considered for the downstream final disposal of the wastewater is to have wastewater treatment plants (WWTP).
5. The wastewater treatment plants and proposes locations are to be considered as to have small and low costs treatment plants at more than one site and/or have one WWTP at a location where all the collected wastewater can be drained.

47. 6. There is a need to solve the problems of the few houses located near the wall and yet not served by the wastewater collection system. 
For the network in the northern part of Qalqilia, it is recommended to do the following:
The municipality has to apply this project to enhance the wastewater management and solve the problem of overload in this active part of Qalqilia.
Construction of an interceptor along the Wadi extending parallel to the wall and having additional outlets through the wall will provide better management of the sewage collection system.

48. Thank you