Drawdown when Steady Flow of Unconfined Aquifer Calculator

✖The steady flow of an Unconfined Aquifer is the rate at which the fluid discharges into the well of an unconfined auifer.ⓘ Steady Flow of an Unconfined Aquifer [Q_u]			+10% -10%
✖Radius at the edge of Zone of Influence which is an area of engineering soils likely to be affected by loading due to engineering or building development.ⓘ Radius at the edge of Zone of Influence [R]			+10% -10%
✖Radius of the Pumping Well at the edge of zone of influence. A Pumping Well is a well in which pumping is required to increase the formation pressure to allow the free production flow.ⓘ Radius of the Pumping Well [R_w]			+10% -10%
✖Transmissivity of an unconfined aquifer describes the ability of the aquifer to transmit groundwater throughout its entire saturated thickness.ⓘ Transmissivity of an Unconfined Aquifer [T]			+10% -10%

✖Drawdown at the Pumping Well is a term applied to the maximum lowering of the groundwater table caused by pumping or artesian flow.ⓘ Drawdown when Steady Flow of Unconfined Aquifer [s_w]

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Formula

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Drawdown when Steady Flow of Unconfined Aquifer

Formula

`"s"_{"w"} = ("Q"_{"u"}*ln("R"/"R"_{"w"}))/(2*pi*"T")`

Example

`"21.00088m"=("65m³/s"*ln("25m"/"6m"))/(2*pi*"0.703m²/s")`

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Drawdown when Steady Flow of Unconfined Aquifer Solution

STEP 0: Pre-Calculation Summary

Formula Used

Drawdown at the Pumping Well = (Steady Flow of an Unconfined Aquifer*ln(Radius at the edge of Zone of Influence/Radius of the Pumping Well))/(2*pi*Transmissivity of an Unconfined Aquifer)
s_w = (Q_u*ln(R/R_w))/(2*pi*T)
This formula uses 1 Constants, 1 Functions, 5 Variables

Constants Used

pi - Archimedes' constant Value Taken As 3.14159265358979323846264338327950288

Functions Used

ln - The natural logarithm, also known as the logarithm to the base e, is the inverse function of the natural exponential function., ln(Number)

Variables Used

Drawdown at the Pumping Well - (Measured in Meter) - Drawdown at the Pumping Well is a term applied to the maximum lowering of the groundwater table caused by pumping or artesian flow.
Steady Flow of an Unconfined Aquifer - (Measured in Cubic Meter per Second) - The steady flow of an Unconfined Aquifer is the rate at which the fluid discharges into the well of an unconfined auifer.
Radius at the edge of Zone of Influence - (Measured in Meter) - Radius at the edge of Zone of Influence which is an area of engineering soils likely to be affected by loading due to engineering or building development.
Radius of the Pumping Well - (Measured in Meter) - Radius of the Pumping Well at the edge of zone of influence. A Pumping Well is a well in which pumping is required to increase the formation pressure to allow the free production flow.
Transmissivity of an Unconfined Aquifer - (Measured in Square Meter per Second) - Transmissivity of an unconfined aquifer describes the ability of the aquifer to transmit groundwater throughout its entire saturated thickness.

STEP 1: Convert Input(s) to Base Unit

Steady Flow of an Unconfined Aquifer: 65 Cubic Meter per Second --> 65 Cubic Meter per Second No Conversion Required
Radius at the edge of Zone of Influence: 25 Meter --> 25 Meter No Conversion Required
Radius of the Pumping Well: 6 Meter --> 6 Meter No Conversion Required
Transmissivity of an Unconfined Aquifer: 0.703 Square Meter per Second --> 0.703 Square Meter per Second No Conversion Required

STEP 2: Evaluate Formula

Substituting Input Values in Formula

s_w = (Q_u*ln(R/R_w))/(2*pi*T) --> (65*ln(25/6))/(2*pi*0.703)

Evaluating ... ...

s_w = 21.0008825802025

STEP 3: Convert Result to Output's Unit

21.0008825802025 Meter --> No Conversion Required

FINAL ANSWER

21.0008825802025 ≈ 21.00088 Meter <-- Drawdown at the Pumping Well

(Calculation completed in 00.004 seconds)

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Transmissivity when Discharge at Drawdown is considered

Go Transmissivity of an Unconfined Aquifer = (Steady Flow of an Unconfined Aquifer*ln(Radius at the edge of Zone of Influence/Radius of the Pumping Well))/(2*pi*Drawdown at the Pumping Well)

Drawdown when Steady Flow of Unconfined Aquifer

Go Drawdown at the Pumping Well = (Steady Flow of an Unconfined Aquifer*ln(Radius at the edge of Zone of Influence/Radius of the Pumping Well))/(2*pi*Transmissivity of an Unconfined Aquifer)

Discharge when drawdown at pumping well is considered

Go Steady Flow of an Unconfined Aquifer = 2*pi*Transmissivity of an Unconfined Aquifer*Drawdown at the Pumping Well/ln(Radius at the edge of Zone of Influence/Radius of the Pumping Well)

Drawdown at Pumping Well

Go Drawdown at the Pumping Well = (Saturated Thickness of the Aquifer-Depth of Water in the Pumping Well)

Drawdown when Steady Flow of Unconfined Aquifer Formula

What is Groundwater Recharge?

Groundwater Recharge or deep drainage or deep percolation is a hydrologic process, where water moves downward from surface water to groundwater. Recharge is the primary method through which water enters an aquifer . This process usually occurs in the vadose zone below plant roots and, is often expressed as a flux to the water table surface.

How to Calculate Drawdown when Steady Flow of Unconfined Aquifer?

Drawdown when Steady Flow of Unconfined Aquifer calculator uses Drawdown at the Pumping Well = (Steady Flow of an Unconfined Aquifer*ln(Radius at the edge of Zone of Influence/Radius of the Pumping Well))/(2*pi*Transmissivity of an Unconfined Aquifer) to calculate the Drawdown at the Pumping Well, The Drawdown when Steady Flow of Unconfined Aquifer is term applied to maximum lowering of groundwater table caused by pumping or artesian flow. Drawdown at the Pumping Well is denoted by s_w symbol.

How to calculate Drawdown when Steady Flow of Unconfined Aquifer using this online calculator? To use this online calculator for Drawdown when Steady Flow of Unconfined Aquifer, enter Steady Flow of an Unconfined Aquifer (Q_u), Radius at the edge of Zone of Influence (R), Radius of the Pumping Well (R_w) & Transmissivity of an Unconfined Aquifer (T) and hit the calculate button. Here is how the Drawdown when Steady Flow of Unconfined Aquifer calculation can be explained with given input values -> 21.00088 = (65*ln(25/6))/(2*pi*0.703).

FAQ

What is Drawdown when Steady Flow of Unconfined Aquifer?

The Drawdown when Steady Flow of Unconfined Aquifer is term applied to maximum lowering of groundwater table caused by pumping or artesian flow and is represented as s_w = (Q_u*ln(R/R_w))/(2*pi*T) or Drawdown at the Pumping Well = (Steady Flow of an Unconfined Aquifer*ln(Radius at the edge of Zone of Influence/Radius of the Pumping Well))/(2*pi*Transmissivity of an Unconfined Aquifer). The steady flow of an Unconfined Aquifer is the rate at which the fluid discharges into the well of an unconfined auifer, Radius at the edge of Zone of Influence which is an area of engineering soils likely to be affected by loading due to engineering or building development, Radius of the Pumping Well at the edge of zone of influence. A Pumping Well is a well in which pumping is required to increase the formation pressure to allow the free production flow & Transmissivity of an unconfined aquifer describes the ability of the aquifer to transmit groundwater throughout its entire saturated thickness.

How to calculate Drawdown when Steady Flow of Unconfined Aquifer?

The Drawdown when Steady Flow of Unconfined Aquifer is term applied to maximum lowering of groundwater table caused by pumping or artesian flow is calculated using Drawdown at the Pumping Well = (Steady Flow of an Unconfined Aquifer*ln(Radius at the edge of Zone of Influence/Radius of the Pumping Well))/(2*pi*Transmissivity of an Unconfined Aquifer). To calculate Drawdown when Steady Flow of Unconfined Aquifer, you need Steady Flow of an Unconfined Aquifer (Q_u), Radius at the edge of Zone of Influence (R), Radius of the Pumping Well (R_w) & Transmissivity of an Unconfined Aquifer (T). With our tool, you need to enter the respective value for Steady Flow of an Unconfined Aquifer, Radius at the edge of Zone of Influence, Radius of the Pumping Well & Transmissivity of an Unconfined Aquifer and hit the calculate button. You can also select the units (if any) for Input(s) and the Output as well.

How many ways are there to calculate Drawdown at the Pumping Well?

In this formula, Drawdown at the Pumping Well uses Steady Flow of an Unconfined Aquifer, Radius at the edge of Zone of Influence, Radius of the Pumping Well & Transmissivity of an Unconfined Aquifer. We can use 1 other way(s) to calculate the same, which is/are as follows -

Drawdown at the Pumping Well = (Saturated Thickness of the Aquifer-Depth of Water in the Pumping Well)

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