Permeability Characteristics of Lower Niger Floodplain Sediments and their Implications for Drainage and Flood Mitigation

Rising flood-related damage to infrastructure across the Lower Niger floodplains has increased the need to understand the permeability of floodplain sediments, both to explain the persistence of flooding and to assess the feasibility of dewatering these areas. These floodplains occupy about 7% of the Niger Delta and are under growing pressure from intensive development. Reliable permeability estimates are essential for flood control, groundwater flow assessment, and contaminant transport analysis, all of which are critical to sustainable land and water management in the region. This study evaluated the permeability of stratified floodplain soils using field pump tests and laboratory constant-head tests, alongside particle size distribution analysis on randomly selected samples from eight boreholes. The particle size data were also used to estimate permeability through an established empirical equation. Permeability values obtained from the field pump test ranged from 1.52 × 10⁻³ to 1.67 × 10⁻³ m/s, while constant-head test values ranged from 4.0 × 10⁻⁴ to 7.1 × 10⁻³ m/s. Empirically derived permeability values averaged 4.7 × 10⁻³ m/s. Comparison of the three methods showed strong agreement, which is attributed to the high grain uniformity of the sediments. The findings indicate that, in uniform granular floodplain soils, field, laboratory, and empirical approaches can produce comparable and acceptable permeability estimates. The measured permeability values further suggest favourable drainage conditions; where hydraulic connection exists between the surface and underlying sandy layers, natural drainage and dewatering could help reduce prolonged flooding in the Lower Niger floodplains.

Floodplain, Flood, Niger Delta, Permeability, Drainage

1. Abam, T.K.S and Fubara, D. M.J (2022). Analysis of Hydrological Characteristics: A Case Review of the Niger Delta. Journal of Water Resource and Protection. [Google Scholar] [Crossref]

2. https://doi.org/10.4236/jwarp.2022.149032 [Google Scholar] [Crossref]

3. Eteh, D., Egobueze, F. E., Paaru, M., Otutu, A. O., & Osondu, I. (2024). The impact of dam management and rainfall patterns on flooding in the Niger Delta: using Sentinel-1 SAR data. Discover Water, 4. https://doi.org/10.1007/s43832-024-00185-8 [Google Scholar] [Crossref]

4. Liu, H., Du, J., & Yi, Y. (2022). Reconceptualising flood risk assessment by incorporating sediment supply. CATENA. https://doi.org/10.1016/j.catena.2022.106503 [Google Scholar] [Crossref]

5. Vázquez-Tarrío, D., Ruiz‐Villanueva, V., Garrote, J., Benito, G., Calle, M., Lúcia, A., & Díez-Herrero, A. (2023). Effects of sediment transport on flood hazards: Lessons learned and remaining challenges. Geomorphology. https://doi.org/10.1016/j.geomorph.2023.108976 [Google Scholar] [Crossref]

6. Tosin-Orimolade, A., Rahman, M., & Ipede, O. (2026). Land Use/Land Cover Change Detection and Assessment of Flood Susceptibility in the Niger Delta Region. Climate. [Google Scholar] [Crossref]

7. https://doi.org/10.3390/cli14050108 [Google Scholar] [Crossref]

8. Fenguia, S. N. D., & Nkouathio, D. (2023). Contribution of soil physical properties in the assessment of flood risks in tropical areas: case of the Mbo plain (Cameroon). Natural Hazards, 116, 3447-3463. https://doi.org/10.1007/s11069-023-05818-0 [Google Scholar] [Crossref]

9. Miller, R. B., Heeren, D., Fox, G., Halihan, T., Storm, D., & Mittelstet, A. (2014). The hydraulic conductivity structure of gravel-dominated vadose zones within alluvial floodplains. Journal of Hydrology, 513, 229-240. https://doi.org/10.1016/j.jhydrol.2014.03.046 [Google Scholar] [Crossref]

10. Nones, M. (2019). Dealing with sediment transport in flood risk management. Acta Geophysica, 67, 677-685. https://doi.org/10.1007/s11600-019-00273-7 [Google Scholar] [Crossref]

11. Mahmood, A., Han, J., Ijaz, M., Siyal, A., Ahmad, M., & Yousaf, M. (2022). Impact of Sediment Deposition on Flood Carrying Capacity of an Alluvial Channel: A Case Study of the Lower Indus Basin. Water. https://doi.org/10.3390/w14203321 [Google Scholar] [Crossref]

12. Bonkoungou, B., Bossa, A., Kwast, J., Mul, M., & Sintondji, L. (2024). Inner Niger Delta Inundation Extent (2010-2022) Based on Landsat Imagery and the Google Earth Engine. Remote. Sens., 16, 1853. https://doi.org/10.3390/rs16111853 [Google Scholar] [Crossref]

13. Oborie, E., & Rowland, E. (2023). Flood influence using GIS and remote sensing based morphometric parameters: A case study in Niger delta region. Journal of Asian Scientific Research. https://doi.org/10.55493/5003.v13i1.4719 [Google Scholar] [Crossref]

14. Agwumafa O F, Weli VE, Eludoyin OS (2021). Flood Risk Assessment of Communities to Flood Hazards in Central Niger Delta, Nigeria. Earth & Environmental Science Research & Reviews. https://doi.org/10.33140/eesrr.04.01.10 [Google Scholar] [Crossref]

15. Kalantari, Z., Ferreira, C., Koutsouris, A., Ahlmer, A.-K., Cerdà, A., & Destouni, G. (2019). Assessing flood probability for transportation infrastructure based on catchment characteristics, sediment connectivity and remotely sensed soil moisture.. The Science of the total environment, 661, 393-406. https://doi.org/10.1016/j.scitotenv.2019.01.009 [Google Scholar] [Crossref]

16. Haque, M., Seidou, O., Mohammadian, A., & Djibo, A. G. (2020). Development of a time-varying MODIS/ 2D hydrodynamic model relationship between water levels and flooded areas in the Inner Niger Delta, Mali, West Africa. Journal of Hydrology: Regional Studies, 30, 100703. https://doi.org/10.1016/j.ejrh.2020.100703 [Google Scholar] [Crossref]

17. Chen, X., Mi, H., Hongman, H., Ruichong, L., Gao, M., Huo, A., & Cheng, D. (2014). Hydraulic conductivity variation within and between layers of a high floodplain profile. Journal of Hydrology, 515, 147-155. https://doi.org/10.1016/j.jhydrol.2014.04.052 [Google Scholar] [Crossref]

18. Ogunkoya, O., & Olayiwola, H. A. (2022). Dam operations, local rainfall, changing settlement growth pattern and flooding in the Niger Delta, Nigeria. River Research and Applications, 38, 1209 - 1223. https://doi.org/10.1002/rra.3994 [Google Scholar] [Crossref]

19. ASTM D422-63 Standard test method for particle-size analysis of soils. [Google Scholar] [Crossref]

20. Head J.M. (1987): “Manual of soil laboratory testing – Vol. 1-111” Pentech Edit – London. [Google Scholar] [Crossref]

21. Oosterbaan R.J. and Nijland H.J., (1994), Determination of the Saturated Hydraulic Conductivity. In: H.P. Ritzema (ed.) Drainage Principles and Applications, ILRI Publication 16, p.435-476. International Institute for Land Reclamation and Improvement, Wageningen, The Netherlands. [Google Scholar] [Crossref]

22. Reijers T. J. A (2011) Stratigraphy and sedimentology of the Niger Delta: Geologos, 17(3): 133-162. doi: 10.2478/v10118-011-0008-3 [Google Scholar] [Crossref]

23. Wösten, J.H.M., Pachepsky, Y.A., and Rawls, W.J. (2001). "Pedotransfer functions: bridging the gap between available basic soil data and missing soil hydraulic characteristics" 251: 123–150. [Google Scholar] [Crossref]

24. Udie J, Subhes C. Bhattacharyya, Leticia Ozawa-Meida (2018) Evaluation of Oil/Gas Infrastructure Exposure to Climate Change Burdens in the Niger Delta. [Google Scholar] [Crossref]

25. Olugunorisa TE (2009) Strategies for Mitigation of Flood Risk in the Niger Delta, Nigeria. Journal of Applied Sciences and Environmental Management. Vol. 13 No. 2 (2009) [Google Scholar] [Crossref]

26. Onugba, Michael Attah, Abraham Onugba, and Margaret Eke Bamigboye. 2022. “Resilient Infrastructure as a Tool for Flood Risk Management in Nigeria: A Review”. Journal of Geography, Environment and Earth Science International 26 (11):37-46. [Google Scholar] [Crossref]

27. https://doi.org/10.9734/jgeesi/2022/v26i11644. [Google Scholar] [Crossref]

• Assessing Environmental Support as a Predictor of Occupational Engagement among Women Entrepreneurs in Delta Districts