Comparative Transportation-Model Optimisation of Water Distribution under Post-Subsidy Freight Costs: A Delta State Case Study

References

[1] Abdullahi, I., et al. (2020). Minimizing cost of transportation by Vogel's Approximation Method: A case study of Maisango Cement Nigeria Plc. Malaysian Journal of Computing and Applied Mathematics.

[2] AllAfrica (2026). Nigeria loses N3.2trn annually to transport inefficiencies – expert. AllAfrica, 23 June 2026.

[3] Akpan, S., Ugbe, T., Usen, J., & Ajah, O. (2015). A modified Vogel approximant method for solving balanced transportation problems. American Journal of Applied Mathematics.

[4] Businessday NG (2023). Juxtaposing transport costs in Lagos with fuel subsidy removal. Businessday, 2 August 2023.

[5] Businessday NG (2024). How high fuel costs hindered transport sector growth in 2023. Businessday, 9 January 2024.

[6] Ezekiel, I. D., & Edeki, S. O. (2018). Modified Vogel Approximation Method for balanced transportation models towards optimal option settings. International Journal of Civil Engineering and Technology, 9(12).

[7] Hillier, F. S., & Lieberman, G. J. (2015). Introduction to Operations Research (10th ed.). New York: McGraw-Hill.

[8] Iheonu, N. O., & Inyama, S. C. (2016). On the optimization of transportation problem. British Journal of Mathematics & Computer Science, 13(4), 1–11. Crossref

[9] Korukoglu, S., & Balli, S. (2011). An improved Vogel's Approximation Method for the transportation problem. Association for the Advancement of Modelling and Simulation Techniques in Enterprises.

[10] Nairametrics (2025). Nigeria's 1.6 million container trade far less than its ports potential – logistics expert. Nairametrics, 23 August 2025.

[11] Premium Times (2023). Food prices, transport fares increase across Nigeria as fuel subsidy removal bites harder. Premium Times, 5 June 2023.

[12] Reeb, J., & Leavengood, S. (1998). Transportation Problem: A Special Case for Linear Programming Problems. Performance Excellence in the Wood Products Industry, EM 8779. Corvallis: Oregon State University Extension Service.

[13] Taha, H. A. (2017). Operations Research: An Introduction (10th ed.). Harlow: Pearson Education.

[14] Veritas University Abuja, Department of Banking and Finance (2022). Comparison of methods of solving transportation problems. American Journal of Theoretical and Applied Statistics.

[15] World Bank (2024). From Survey to Big Data: Measuring Logistics Performance. Washington, DC: World Bank Logistics Performance Index Documentation.

@article{1722997,
      author = {Ekpu Nduka Victor},
      title = {Comparative Transportation-Model Optimisation of Water Distribution under Post-Subsidy Freight Costs: A Delta State Case Study},
      journal = {Iconic Research And Engineering Journals},
      year = {2026},
      volume = {10},
      number = {3},
      pages = {1235-1244},
      issn = {2456-8880},
      url = {https://www.irejournals.com/formatedpaper/1722997.pdf},
      abstract = {Nigeria's May 2023 fuel-subsidy removal raised haulage costs sharply, strengthening the case for formal route-allocation over informal, experience-based distribution. This paper applies and compares four classical transportation-model procedures (North-West Corner (NWCM), Least-Cost (LCM), Vogel's Approximation (VAM), and the Modified Distribution (MODI) optimality test) to a simulated case study of a pure-water sachet factory operating three depots and four demand zones in Agbor, Delta State. Unlike comparable Nigerian case studies, the unit-cost matrix here is not judgementally assigned but derived from route distances, an assumed fuel-consumption rate, a representative diesel price, and a fixed handling charge, making the cost structure reproducible. On a balanced 3×4, 1,900-carton-per-week network, NWCM costs ₦100,650/week; LCM and VAM independently reach the same allocation, ₦86,750; MODI, applied through two stepping-stone iterations, finds a further-improving route and converges on the true optimum, ₦85,850, confirmed by a linear-programming solver. That LCM and VAM agree yet both fall short of optimal shows MODI is a necessary, not merely confirmatory, step. The MODI-verified allocation cuts weekly cost by 14.7% versus NWCM, consistent with the 10-40% range reported elsewhere. A 25%-diesel-price sensitivity check leaves the optimal routing unchanged, though not its cost. The paper situates this firm-level result against inconsistent published estimates of Nigeria's logistics-cost share of GDP, arguing firm-level optimisation is necessary but not sufficient for any macro-level target.},
      keywords = {transportation problem; linear programming; Vogel's Approximation Method; MODI method; supply chain optimisation; fuel subsidy; Nigeria.},
      month = {September},
      doi = {https://doi.org/10.64388/IREV10I3-1722997}
  }