Isolation Works - Inspection Report

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MANAGEMENT ENGINEERING SERVICES CONTRACT FARA 2 Implementing Non Revenue Water Reduction in DZ 27 Isolation Works - Inspection Report Submission Date: March 21, 2016 Contract Number:

1 MANAGEMENT ENGINEERING SERVICES CONTRACT FARA 2 Implementing Non Revenue Water Reduction in DZ 27 Isolation Works - Inspection Report Submission Date: March 21, 2016 Contract Number: AID-278-C Contract Period: March 16, 2015 to March 15, 2018 COR Name: Eng. Louis Qaqish Submitted by: Raid Zraikat, Chief of Party Engicon Amman, Ahmad Bin Hanbal Street Bld. 127 Tel: rzraikat@engicon.com This report was produced for review by the United States Agency for International Development (USAID). It was prepared by Engicon under Contract AID-278-C

2 CONTENTS Contents EXECUTIVE SUMMARY Introduction Report Annexes INTRODUCTION Project Area Project Objective ISOLATION WORKS Hydraulic Analysis and Re-districting General Isolation Process Isolation Process as Carried out in DZ DZ 27 A DZ 27 A DZ 27 A DZ 27 B DZ 27 D DZ 27 E DZ 27 E ANNEXES Isolation Pictures Wet/Dry Test Form: Example for DZ 27 E Shifted Borders Wet/Dry Test Results Summary

3 1. EXECUTIVE SUMMARY 1.1 INTRODUCTION This report summarizes the isolation process for the Tareq Water Distribution Zone (DZ 27), which is part of the Amman Non-Revenue Water project funded by USAID. The report covers all stages of the isolation process from the design/preparatory work to the successful wet/dry tests that verified that DZ27 and all its districts are now hydraulically isolated. Preparatory work included data collection, detailed distribution zone analysis, main feeders investigation and hydraulic modelling. The needed isolation tasks were implemented by Miyahuna, with oversight by the MESC team, to come up with an improved hydraulic solution, with isolation as the immediate goal but also with better control of the network and reduced pressure gradients within districts where this was found to be excessive under the existing configuration. 1.2 REPORT This report describes the project area and the project objective in Chapter 1. Chapter 2 is a detailed description of the isolation process starting from the hydraulic analysis and ending with the successful wet/dry tests. 1.3 ANNEXES Annexes contained in Chapter 3 include isolation pictures, an example wet/dry test form, a diagram showing the shifted borders that resulted from the wet/dry tests, and a summary table showing the isolation verification by the MESC team. 3

4 2. INTRODUCTION 2.1 PROJECT AREA DZ 27 was originally divided into four districts as shown in Figure 1 below: 1. District 27A 2. District 27B 3. District 27D 4. District 27E Figure 1: DZ27 original pressure districts borders 4

5 2.2 PROJECT OBJECTIVE The importance of the isolation of distribution zones (DZs) and their constituent districts (in this case DZ 27A, 27B, etc) cannot be overstated. NRW reduction in DZ 27 (and any other DZ) starts with the isolation of each district within that DZ, and then isolating the DZ as a whole at its external boundaries (if needed) to ensure that no unmetered water can flow between districts, or to/from adjacent DZs, or to/from redundant pipes (ie old pipes since superseded by newer ones in the same location). Since water inflows and outflows for a district are measured through district meters (inflow) and customers meters (outflow), isolating each DZ and its districts is essential for accurate NRW calculations and to control were water is directed under Amman s intermittent supply distribution. By their nature, isolation activities may also reveal leaks, which are also to be corrected at this stage. Therefore, isolation may actually reduce NRW, although the extent cannot be measured. 5

6 3. ISOLATION WORKS 3.1 HYDRAULIC ANALYSIS AND RE-DISTRICTING The first step was to update the GIS database for DZ 27 through data collection, site visits and meetings with relevant personnel from Miyahuna s Operation and Maintenance Department. Then, after analyzing the existing network and tracking the main feeders and tertiary pipelines for each district within DZ 27, it was concluded that the four original districts were not isolated, which was caused by many cross connections between them. In addition there were other difficulties in DZ 27, including the large number of customers in some districts and large differences in elevation within districts that in some cases exceeded 170 m (meaning that pressure varied greatly from one part of a district to another, causing excessive pressure in some locations and thus increased leakage). The MESC team then performed hydraulic analysis for DZ 27 to examine the actual performance of the network, then the district borders were revised and network upgraded to achieve the best hydraulic performance with minimum expected costs. Taking into consideration the hydraulic analysis, the location of customers, the difference in elevation in this location and other geographical features, DZ 27 s districts were then divided as follows: 6

7 District 27 A: divided into 27 A1, 27 A2 and 27 A3. 7

9 District 27E: divided into 27 E1 and 27 E2. 27E2 27E1 27E1 9

District 27B: district 27B s border was modified and a part of it was combined with a neighboring distribution zone. 27B As for district 27 D only required minor shifting of the borders.

11 District 27B: district 27B s border was modified and a part of it was combined with a neighboring distribution zone. 27B As for district 27 D only required minor shifting of the borders. As a result of the redistricting, the number of DZ 27 districts increased from 4 to 7. The characteristics of each of these 7 districts, and DZ 27 as a whole, are listed in the next table. 11

12 GIS Name No. of Customers Area in KM² Total Length of Network (Excluding Service Connections) Length of Network GIP in KM Length of Network HDPE in KM Total Length of Service Connection in KM 72A A A B D E E SUM GENERAL ISOLATION FIELD ACTIVITIES The isolation process occurred in two phases as follows: Phase 1: Characterization of the district, which involves studying the district s GIS records along with physical inspection of the water supply system. Phase 2: Walking all district boundaries and installing any needed boundary meters and/or valves, and installing new pipes or end caps, followed by as many wet/dry tests as needed until each district is confirmed isolated (a wet/dry test shows whether water is passing across a boundary or not). A successful wet/dry test for each district is the measure of successful isolation. 3.3 ISOLATION PROCESS AS CARRIED OUT IN DZ 27 The following is a summary of the isolation process in DZ 27, which was conducted by Miyahuna and checked by the MESC team: The work started on the 27th of October, 2015 and finished on.; This task was accomplished by expert technicians from Miyahuna s Operation and Maintenance Department; 12

13 Taking advantage of the intermittent supply, the work was carried out as follows: a. Disconnection works for 3 days weekly when the water was off; b. Wet/dry tests during the 3 days of supply and the dry days for the adjacent districts. The physical isolation methods used were a combination of: a. Complete pipe disconnection, by cutting the applicable pipe and plugging each end with an end cap; b. Installation of isolation valves; c. Closure of existing isolation valves; d. Shifting the district borders in the GIS as needed, so that the GIS agrees with the actual situation; e. Installation of new pipelines. The initial number of disconnection points as per the isolation drawings based on existing GIS database was 24 points; The wet/dry tests resulted in the addition of 23 disconnection points. The fact that 47 boundary breaches had to be corrected shows how much work was involved in isolating DZ 27 and its districts. The following sections summarise the isolation process in each district DZ 27 A1 This district has the largest area and includes the highest number of customers amongst all districts in DZ 27. It also borders another 11 districts as shown in the figure below. Therefore, isolation of this district was considered a tough job. 13

18C 27A3 27A3 26D 27B 28Z1 27A2 University 27D 28B Unive 27E2 28A 21C 27E2 28H 21B 27E1 27E1 28C 23B 29A 28D The initial number of disconnection points based on the GIS database was 7, while the

14 18C 27A3 27A3 26D 27B 28Z1 27A2 University 27D 28B Unive 27E2 28A 21C 27E2 28H 21B 27E1 27E1 28C 23B 29A 28D The initial number of disconnection points based on the GIS database was 7, while the wet/dry tests resulted in another 12 points. The following is the summary of these isolation points: Five points were found already disconnected; Two points: line was not found in site, mostly a GIS error; Three points: disconnection with end caps; Two points: disconnection with end cap from one side and reconnection with another pipe on the other side, in order to move this part from one district to another; 14

Four points: installation of an isolation valve; Two points: closure of an existing valve; One point: shifted border in the GIS. 3.

15 Four points: installation of an isolation valve; Two points: closure of an existing valve; One point: shifted border in the GIS DZ 27 A2 This district shares its borders with another 5 districts as shown in the following figure. Despite this, isolation of this district was simple. 26D 27A2 28Z1 27D 28B The number of disconnection points based on the GIS database was 3, and after making the corrections as below the district passed the wet/dry test without any further disconnections. The following is the summary of these isolation points: One point: disconnection with end caps; Two points: installation of an isolation valve. 15

3.3.3 DZ 27 A3 This district has a relatively small area. The GIS database showed that this district didn t require any isolation, and it passed the wet/dry test without any corrections. 3.3.4 DZ 27 B This district has the lowest number of customers.

16 3.3.3 DZ 27 A3 This district has a relatively small area. The GIS database showed that this district didn t require any isolation, and it passed the wet/dry test without any corrections DZ 27 B This district has the lowest number of customers. The GIS database showed that this district didn t require any isolation, and it passed the wet/dry test without any corrections DZ 27 D This district shares its borders with another 4 districts as shown in the figure below. 28Z1 27A2 27D 28B 27E2 28A The initial number of disconnection points based on the GIS database was 3, while the wet/dry tests resulted in another 4 points. The following is the summary of these isolation points: One point was found already disconnected; One point: disconnection with end caps; 16

One point: disconnection with end cap from one side and reconnection with a newly installed pipe from another side; Three points: installation of an isolation valve; Two points: closure of an

17 One point: disconnection with end cap from one side and reconnection with a newly installed pipe from another side; Three points: installation of an isolation valve; Two points: closure of an existing valve; One point: connection of pipe with another pipeline in order to move this part from one district to another DZ 27 E1 This district shares its borders with another 6 districts as shown in the figure below. It was originally one district which was divided in two as a result of the hydraulic analysis. Therefore isolation of this district was considered a tough job. 27E2 28H 23B 27E1 29A 27E1 28C 28D The initial number of disconnection points based on the GIS database for this district was 4 points, while the wet/dry tests resulted in another 8 points. The following is the summary of these isolation points: Two points: line was not found; Three points: disconnection with end caps; Three points: installation of an isolation valve; One point: installation of a valve along with shifting borders in the GIS; Two points: shifting borders in the GIS; One point: already disconnected. 17

18 3.3.7 DZ 27 E2 As mentioned above, this district is the result of a division of the originally designed district 27 E into two districts. This district shares its borders with another 7 districts as shown in the figure below. 27D 28B 27E2 28A 27E2 28H 21B 27E1 27E1 28C 23B 29A The initial number of disconnection points based on the GIS database was 2, while the wet/dry tests resulted in another 4 points. The following is the summary of these isolation points: 28D Two points: disconnection with end caps; Three points: installation of an isolation valve; One point: excavation of completely buried valves and opening them. 18

19 The following figure shows the old DZ 27 districts borders in black, and the new districts colored and hatched. 27A3 27A3 27B 27A2 27D 27E2 27E2 27E1 27E1 19

20 4. ANNEXES 4.1 ISOLATION PICTURES Isolation by cutting and plugging with end caps Isolation by installing a valve Disconnection of one pipeline and reconnection with another pipe 20

21 Investigation using a pipe locator Pipe installation Rehabilitation of isolation valves Pipe investigation 21

22 4.2 WET/DRY TEST FORM: EXAMPLE FOR DZ 27 E1 Test Name: Wet / Dry Test No.: 7 Date: Friday, 25, Dec, 2015 Location: DZ 27E1 / DZ 27E2 Team: Name Mazen Saadeh Murad Atta Ibrahim Nimr Position Miyahuna / Distrib. Miyahuna / Distrib. Miyahuna / Distrib. Action: Closing supply valve 200 mm (Exist valve) for DZ 27E1 near Kuwaiti Building. DZ DZ Result Reaction DZ 27E1 DZ Passed from test 1DZ DZ 27E1 DZ 27E2 Passed Shift area DZ 27E1 DZ 28C Passed DZ 27E1 DZ 23B Passed DZ 27E1 DZ 27E1 DZ 29A DZ 28D Passed Passed DZ 27E2 Wet DZ DZ 28C DZ 27E1 Dry DZ 28D DZ 23B DZ 29A 22

23 4.3 SHIFTED BORDERS 23

24 4.4 WET/DRY TEST RESULTS SUMMARY 24 Ministry of Water and Irrigation/MWI.0 Kufranja-King Talal Pipeline Draft Design Report

25 26 Ministry of Water and Irrigation/MWI.0 Kufranja-King Talal Pipeline Draft Design Report

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