How do you measure drawdown while you are pumping?
How do you measure drawdown while you are pumping?
If you have a traditional water level tape, you drop it down into the water, it completes the circuit, and the sounder goes off. The only way to really measure drawdown is to, every minute or two, drop the tape down and record the level. Now QED manufactures a tape that’s a combination of a water level tape and a drawdown meter. You drop your tape down well and record your water level measurement below grade, then you flip a switch on the unit and it reverses the circuit. Now the sounder makes a noise when it's out of the water as opposed to in the water. For example, if your water level is 20.5 feet below the top of the casing, write that down, then lower the unit about a foot and flip the switch. Now, simply lift up the tape and see whether or not it beeps. If you started with two feet of submergence and you lift the tape a foot and a half and it beeps, you know you have half a foot of drawdown. It's a quick way to get a measurement. Also, that same type of drawdown meter can be connected to a digital controller, which actually stops the controller or pauses it. Using devices such as transducers would be nice because you get a continuous readout but they tend to be kind of expensive for that approach.
If you have a traditional water level tape, you drop it down into the water, it completes the circuit, and the sounder goes off. The only way to really measure drawdown is to, every minute or two, drop the tape down and record the level. Now QED manufactures a tape that’s a combination of a water level tape and a drawdown meter. You drop your tape down well and record your water level measurement below grade, then you flip a switch on the unit and it reverses the circuit. Now the sounder makes a noise when it's out of the water as opposed to in the water. For example, if your water level is 20.5 feet below the top of the casing, write that down, then lower the unit about a foot and flip the switch. Now, simply lift up the tape and see whether or not it beeps. If you started with two feet of submergence and you lift the tape a foot and a half and it beeps, you know you have half a foot of drawdown. It's a quick way to get a measurement. Also, that same type of drawdown meter can be connected to a digital controller, which actually stops the controller or pauses it. Using devices such as transducers would be nice because you get a continuous readout but they tend to be kind of expensive for that approach.