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A Novel Groundwater Recharge Using Stormwater Drainage
Published in Saeid Eslamian, Faezeh Eslamian, Flood Handbook, 2022
Manisha Desai, Jayantilal Patel, Saeid Eslamian
The infiltrometer (single infiltrometer and double infiltrometer) is used to determine the infiltration rate. Horton's equation can be used to compute the infiltration rate. Horton's equation is another viable option when measuring ground infiltration rates or volumes. It is an empirical formula that says that infiltration starts at a constant rate, fo and is decreasing exponentially with time, t. After some time when the soil saturation level reaches a certain value, the rate of infiltration will level off to the rate fc. ft=fc+fo−fce−kt
Hydrologie Cycle and Rainfall-Runoff Processes
Published in Monzur A. Imteaz, Urban Water Resources, 2019
The infiltration rate is measured using a simple device named infiltrometer. It is basically two eccentric annular rings/pipes of different diameter penetrated within the soil, as shown in Figure 2.15. Water is poured within the pipe columns and water starts receding within the pipes as infiltration continues. Reductions in water level within the inner pipe are measured at different times until the rate of recession becomes constant. Water filled in the outer pipe helps to eliminate the effect of horizontal flow within the soil. Figure 2.16 shows a typical infiltration rate curve with time for different types of soils, which shows a typical higher infiltration rate at the beginning and becomes constant at one stage. Mathematically, this figure can be represented using Horton’s equation: ft=fc+(f0−fc)*e−kt
Infiltration Hydrologie Design
Published in K. Ferguson Bruce, Stormwater Infiltration, 2017
A double-ring or concentric-ring infiltrometer is widely used. It attempts to measure only vertical infiltration by eliminating the effects of lateral spreading. As shown in Figure 4.1, an outer concentric ring or box surrounds the infiltrometer and is kept filled simultaneously with the infiltrometer. The area between the inner and outer rings serves as a buffer, confining infiltration from the inner basin to vertical movement. Infiltration rate is measured only in the inner basin, giving an estimate of true vertical rate. Various heights, widths, numbers of rings and measuring methods have been used, all having their benefits and deficiencies.
Rate of infiltration for different soil textures using rainfall simulator and Green–Ampt model
Published in ISH Journal of Hydraulic Engineering, 2021
Infiltration is the process by which water on the ground surface enters the soil. IR is a measure of the rate at which soil is able to absorb rainfall or irrigation. It is measured in inches per hour or millimeters per hour. The rate decreases as the soil become saturated. If the precipitation rate exceeds the IR, surface runoff will usually occur unless there is some physical barrier. It is related to the saturated hydraulic conductivity of the near-surface soil. The rate of infiltration can be measured using an infiltrometer. The methods of measuring the rate of infiltration presented in this paper are