A Micro Study to Determine Porosity, Hydraulic Conductivity, Permeability and the Discharge Rate of Groundwater in Ondo State Riverbeds, Southwestern Nigeria

Abstract

Laboratory study of three riverbed soil samples denoted as A, B and C have been carried out by determining the soils Porosity, Hydraulic conductivity, Permeability and also investigating if there are points of convergence between the discharge rate and angle of tilt for the above mentioned samples. The experimental results for Porosity were approximately within 34%-37%, Hydraulic conductivity was within 3.02 × 10 −5-9.70 × 10 −5 (m/s) and Permeability was within 2.74 × 10 −12-8.80 × 10 −12 (m 2). Pressure generally increases as distance of flow increases for θ = 5˚-25˚ but there was decrease in pressure as distance of flow increases for all three samples when θ = 0˚. The points of convergence for the discharge rate ranged from 0.001 × 10 −10-4.54 × 10 −10 (m 3 /s), while the angle of tilt convergence points ranged from 0.1˚ to 3.6˚. There was increase in discharge rate as angle of tilt increases for all three samples.

Variability of Darcian Flux in the Hyporheic Zone at a Natural Channel Bend

“…In general, the hydraulic conductivity could increase with the increasing porosity, but a negative correlation between them also was found under certain distributions and packing arrangements of grain size [28,37,38]. Unlike for Kv, there were no significant differences in porosity, with an equal median value of 0.41 during both test periods (Table 2).…”

“…The volumetric approach was used to determine the porosity of sediments by calculating the sediment bulk and particle density [28]. Wet saturated sediments inside the pipes were oven dried and weighed using a sensitive scale weighing balance to determine the bulk density.…”

Assessment of Hydraulic Conductivity of Porous Media Using Empirical Relationships

“…The representative grain size of porous media from the gradation analysis is helpful in the assessment of K values [11]. Various properties influenced the K of porous sediments i.e., porosity, structure alignment as well as different properties of fluid such as temperature and viscosity [12].…”