TITLE
Estimation of hydraulic diffusivity and associated hydraulic parameters using pumping test and lithological data in Wasinmi residential community, south-west Nigeria
AUTHOR(S)
Ishola, S.A.
ABSTRACT
Pumping tests were conducted on existing 50 wells (twenty five each) with constant rate pumping test for boreholes and recovery method test for hand-dug wells within district to evaluate aquifer hydraulic parameters and estimate hydraulic Diffusivity within Wasinmi district, South-West Nigeria adopting standard methods of Cooper and Jacob straight line solution to time-drawdown data collected from observation wells. The depth range of 4.3m to 2.4m with a mean depth of 8.3m; mean static water level (SWL) of 1.59m and mean drawdown (DD) of 0.85m while the boreholes tapped fresh water from weathered sandstone aquifer with a depth range of 35m to 75m with a mean depth of 51m, SWL of 17.8m and DD of 8.17m. Borehole discharge varied from 1.0×10-2 l/s to 11.0×10-2 l/s with a mean of 4.0×10-2 l/s with exhibited transmissibility that varied from 1.0×10-2 m2/s to 9.20×10-2 m2/s with an mean of 4.5×10-1 m2/s (40,500 m2/day) while discharge from hand-dug wells ranged from 1.0×10-4 to 6.0×10-2 l/s with a mean of 2.3×10-2 l/s with exhibited transmissibility that varied from 1.0×10-1 (8.64 m2/day) to 5.10×10-1 m2/s(44,064 m2/day) with a mean of 1.42×10-1 m2/s (12,269 m2/day). The hydraulic conductivity varied from 87.96m2/day to 4397.76 m2/day in the boreholes and 594.432 m2/day to 7762.18 m2/day in the hand-dug wells. The mean recovery period of 2254 and 9446 seconds were reported for Wasinmi boreholes and hand-dug wells respectively. Output from the two water sources revealed that the auriferous zones were classified as very high in potentials in the designation of transmissivity magnitudes of 38,880 and 12,269 m2/day for the boreholes and hand-dug wells respectively; based on standard aquifer potentiality classification. This correlates well with the lithological description of the study area displaying fractured shale/clay-shale/clayey sand and weathered sandstone as groundwater bearing unit releasing water into the well with good correlation coefficient between transmissibility and specific capacity (R^2= -0.74 and R^2= 0.715) respectively reported for Wasinmi boreholes and hand-dug well Hydraulic diffusivity varied from 11.816 m2/s to 13,022.87 m2/s in Wasinmi Boreholes and 4.06 m2/s to 6467.26 m2/s in Wasinmi hand-dug wells with the regions of higher hydraulic diffusivity values were comparatively favourable for groundwater development.
DOI
https://doi.org/10.62252/NSS.2025.1035
PAGES: 586-622
How to cite this article:
Ishola, S.A. 2025. Estimation of hydraulic diffusivity and associated hydraulic parameters using pumping test and lithological data in Wasinmi residential community, south-west Nigeria. Naturalis Scientias, 2 (2): 586-622. DOI: https://doi.org/10.62252/NSS.2025.1035. www.naturalisscientias.com.