Non-Revenue Water in Malaysia: Influence of Water Distribution Pipe Types
Abstract
:1. Introduction
NRW in Malaysia
2. Literature Review
2.1. Non-Revenue Water (NRW)
2.2. Types of Water Pipes
2.2.1. Ductile Iron Pipes
2.2.2. Mild Steel Pipes
2.2.3. Polyethylene Pipes
3. Research Methodologies
4. Results
5. Discussion
6. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
Appendix A
Variables | Variables Definition |
---|---|
Dependent | |
NRWi,t | Non-Revenue Water Loss in million liters per day; |
Experimental | |
LMSi,t | Length of Mild Steel pipes in kilometer; |
LDIi,t | Length of Ductile Iron pipes in kilometer; |
LPEi, t | Length of Polyethylene pipes in kilometer; |
LOPi, t | Length of Other pipes in kilometer (inclusive of galvanized iron (GI) and acrylonitrile butadiene (ABS); |
Control | |
DVCi,t | Domestic Volume of Water Consumption in million liters per day; |
NDVCi,t | Non-Domestic Volume of Water Consumption in million liters per day; |
WSISi,t | Number of Water Services Interruption Scheduled. |
WSIUSi,t | Number of Water Services Interruption Unscheduled. |
WSCi,t | Number of Water Services Complaints of Pipe Burst, Breakages and Leak |
POPSERi,t | Population served by state. |
Year | Year dummy. |
Appendix B
Appendix C
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States | 2013 | 2014 | 2015 | 2016 | 2017 | Total (MLD) | |
---|---|---|---|---|---|---|---|
Johor * | NRW(MLD) | 417 | 426 | 436 | 450 | 433 | 2162 |
NRW (%) | 26.4 | 25.9 | 25.6 | 25.9 | 24.7 | ||
Kelantan * | NRW(MLD) | 228 | 220 | 222 | 232 | 234 | 1136 |
NRW (%) | 53.1 | 49.4 | 49.0 | 49.4 | 49.3 | ||
Malacca * | NRW(MLD) | 107 | 102 | 93 | 95 | 101 | 498 |
NRW (%) | 22.1 | 21.4 | 19.3 | 19.0 | 19.6 | ||
Negeri Sembilan | NRW(MLD) | 267 | 267 | 264 | 253 | 245 | 1296 |
NRW (%) | 36.3 | 35.9 | 34.8 | 32.7 | 32.6 | ||
Penang * | NRW(MLD) | 180 | 182 | 202 | 227 | 231 | 1022 |
NRW (%) | 18.2 | 18.3 | 19.9 | 21.5 | 21.9 | ||
Pahang | NRW(MLD) | 561 | 588 | 596 | 532 | 528 | 2,805 |
NRW (%) | 52.7 | 53.1 | 52.8 | 47.9 | 47.5 | ||
Perak * | NRW(MLD) | 365 | 379 | 382 | 402 | 406 | 1934 |
NRW (%) | 30.4 | 30.6 | 30.3 | 30.5 | 30.9 | ||
Perlis * | NRW(MLD) | 132 | 121 | 124 | 148 | 152 | 677 |
NRW (%) | 62.4 | 55.8 | 56.3 | 60.7 | 63.1 | ||
Sabah * | NRW(MLD) | 602 | 618 | 677 | 634 | 679 | 3210 |
NRW (%) | 53.2 | 51.7 | 55.1 | 52.0 | 53.8 | ||
Sarawak * | NRW(MLD) | 359 | 381 | 423 | 479 | 529 | 2171 |
NRW (%) | 31.3 | 32.0 | 33.3 | 36.0 | 37.8 | ||
Selangor | NRW(MLD) | 1575 | 1545 | 1497 | 1547 | 1526 | 7672 |
NRW (%) | 34.5 | 33.6 | 32.0 | 32.2 | 31.5 | ||
Terengganu | NRW(MLD) | 210 | 188 | 192 | 189 | 186 | 965 |
NRW (%) | 33.8 | 31.0 | 31.0 | 30.0 | 30.4 | ||
Kedah * | NRW(MLD) | 675 | 596 | 614 | 637 | 651 | 3173 |
NRW (%) | 50.9 | 46.1 | 46.7 | 46.7 | 47.5 | ||
Labuan * | NRW(MLD) | 16 | 20 | 22 | 22 | 23 | 103 |
NRW (%) | 25.9 | 29.5 | 30.9 | 30.5 | 32.0 |
States | 2013 | 2014 | 2015 | 2016 | 2017 | Total |
---|---|---|---|---|---|---|
Johor | 57,627 | 61,525 | 62,697 | 63,551 | 58,306 | 303,706 |
Kelantan | 11,179 | 16,257 | 16,062 | 25,870 | 41,191 | 110,559 |
Malacca | 33,948 | 24,712 | 22,897 | 30,923 | 33,514 | 145,994 |
Negeri Sembilan | 27,945 | 29,180 | 28,740 | 32,026 | 30,215 | 148,106 |
Penang | 47,959 | 43,517 | 42,947 | 47,977 | 39,809 | 222,209 |
Pahang | 4081 | 2471 | 5018 | 6917 | 7039 | 25,526 |
Perak | 32,987 | 39,322 | 24,332 | 13,362 | 13,131 | 123,134 |
Perlis | 7295 | 7456 | 6381 | 5523 | 1413 | 28,068 |
Sabah | 15,276 | 18,050 | 18,231 | 17,996 | 14,096 | 83,649 |
Sarawak | 15,239 | 16,769 | 21,629 | 16,325 | 14,786 | 84,748 |
Selangor | 125,114 | 136,163 | 123,673 | 123,930 | 164,199 | 673,079 |
Terengganu | 21,252 | 20,282 | 23,496 | 22,336 | 21,048 | 108,414 |
Kedah | 44,825 | 40,357 | 40,295 | 37,212 | 38,312 | 201,001 |
Labuan | 1151 | 893 | 354 | 564 | 1643 | 4605 |
Variable | Mean | Std. Dev | Quartile 1 | Median | Quartile 3 |
---|---|---|---|---|---|
NRWi,t | 412.03 | 368.92 | 186.5 | 313.00 | 553.8 |
LMSi,t | 2959.50 | 3701.53 | 901.5 | 1587.00 | 3139.8 |
LDIi,t | 826.03 | 931.39 | 96.5 | 541.00 | 1123.8 |
LPEi,t | 1839.84 | 1693.08 | 687.5 | 944.00 | 2234.5 |
LOPi,t | 4775.06 | 3718.73 | 2166 | 4508 | 5164 |
DVCi,t | 45.65 | 437.28 | 203.0 | 319.00 | 510.8 |
NDVCi,t | 290.54 | 308.81 | 176.0 | 217.00 | 329.8 |
WSISi,t | 339.43 | 470.38 | 18.75 | 185.50 | 452.00 |
WSIUSi,t | 9201.73 | 18,503.05 | 404 | 3948.50 | 6566 |
WSCi,t | 32,325.69 | 33,210.19 | 13,546 | 23,196.50 | 40,174 |
POPSERi,t | 2099.15 | 1569.18 | 1091.4 | 1720.55 | 2692.1 |
Variables | NRW | LDI | LMS | LPE | LOP | DVC | NDVC | WSIS | WSIUS | POPSER | WCS |
---|---|---|---|---|---|---|---|---|---|---|---|
NRW | 1 | ||||||||||
(0.000) | |||||||||||
LDI | 0.471 | 1 | |||||||||
(0.000) | (0.000) | ||||||||||
LMS | 0.872 | 0.316 | 1 | ||||||||
(0.000) | 0.008 | (0.000) | |||||||||
LPE | 0.214 | 0.483 | −0.122 | 1 | |||||||
0.074 | (0.000) | 0.315 | (0.000) | ||||||||
LOP | 0.579 | 0.374 | 0.533 | −0.007 | 1 | ||||||
(0.000) | 0.001 | (0.000) | 0.954 | (0.000) | |||||||
DVC | 0.891 | 0.546 | 0.786 | 0.197 | 0.671 | 1 | |||||
(0.000) | (0.000) | (0.000) | 0.101 | (0.000) | (0.000) | ||||||
NDVC | 0.881 | 0.565 | 0.829 | 0.139 | 0.576 | 0.867 | 1 | ||||
(0.000) | (0.000) | (0.000) | 0.252 | (0.000) | (0.000) | (0.000) | |||||
WSIS | 0.805 | 0.495 | 0.777 | 0.126 | 0.579 | 0.794 | 0.795 | 1 | |||
(0.000) | (0.000) | (0.000) | 0.300 | (0.000) | (0.000) | (0.000) | (0.000) | ||||
WSIUS | 0.712 | 0.222 | 0.617 | 0.208 | 0.386 | 0.767 | 0.729 | 0.781 | 1 | ||
(0.000) | 0.065 | (0.000) | 0.084 | 0.065 | (0.000) | (0.000) | (0.000) | (0.000) | |||
POPSER | 0.900 | 0.613 | 0.867 | 0.222 | 0.668 | 0.897 | 0.874 | 0.840 | 0.640 | 1 | |
(0.000) | (0.000) | (0.000) | 0.081 | (0.000) | (0.000) | (0.000) | (0.000) | (0.000) | (0.000) | ||
WCS | 0.782 | 0.423 | 0.745 | −0.046 | 0.655 | 0.826 | 0.818 | 0.697 | 0.662 | 0.785 | 1 |
(0.000) | (0.000) | (0.000) | 0.701 | (0.000) | (0.000) | (0.000) | (0.000) | (0.000) | (0.000) | (0.000) |
NRW | Model (1) | Model (2) |
---|---|---|
LDI | 0.0207 | −0.0058 |
0.089 | (−0.126) | |
LMS | 0.0842 ** | 0.0849 ** |
6.019 | 3.347 | |
LPE | 0.071 ** | 0.0687 * |
4.395 | 4.699 | |
LOP | 0.013 | −0.0037 |
0.997 | (−0.594) | |
DVC | 0.7567 | |
1.627 | ||
NDVC | −0.5648 | |
(−0.668) | ||
WSIS | 0.1329 | |
1.228 | ||
WSIUS | −0.0032 | |
(−1.236) | ||
POPSER | −0.0857 | |
(−1.251) | ||
WSC | 0.0009 | |
0.304 | ||
Year fixed-effect | Included | Included |
R-Squared | 0.8821 | 0.9179 |
Adjusted R2 | 0.8666 | 0.8970 |
N observations | 70 | 70 |
F-Statistics | 57.05 | 43.90 |
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Jones, L.J.N.; Kong, D.; Tan, B.T.; Rassiah, P. Non-Revenue Water in Malaysia: Influence of Water Distribution Pipe Types. Sustainability 2021, 13, 2310. https://doi.org/10.3390/su13042310
Jones LJN, Kong D, Tan BT, Rassiah P. Non-Revenue Water in Malaysia: Influence of Water Distribution Pipe Types. Sustainability. 2021; 13(4):2310. https://doi.org/10.3390/su13042310
Chicago/Turabian StyleJones, Lim Jen Nee, Daniel Kong, Boon Thong Tan, and Puspavathy Rassiah. 2021. "Non-Revenue Water in Malaysia: Influence of Water Distribution Pipe Types" Sustainability 13, no. 4: 2310. https://doi.org/10.3390/su13042310
APA StyleJones, L. J. N., Kong, D., Tan, B. T., & Rassiah, P. (2021). Non-Revenue Water in Malaysia: Influence of Water Distribution Pipe Types. Sustainability, 13(4), 2310. https://doi.org/10.3390/su13042310