You can know if your well pump is bad or the well is dry by opening up the well cap and measuring the static water level in the well and seeing how much if any water is in the well.
If your static water levels is too low and below the pump then it won't pump water even with a good well pump.
If your well has water above the pump or your well is not dry then it can be your pump or even your well pressure switch or breaker.
If the well has water then you should check the amp draw on the well pump and is it is drawing higher amps than normal than the well pump is bad or if the the well pump is not coming on at all it could be bad or you could have a bad well pressure switch.
Another cause of no water from a well pump is a broken drop pipe in the well or a leak in a fitting or the pipe in the well.
Pulling the well pump or if you have a jet pump, checking the pumps prime or remove the foot valve at the bottom of the well can help you determine if the well pump or foot valve in the jet pump pipe is bad.
If a well runs dry and the pump is running and not getting cooled by the water or pumping water then the well pump will burn out and lock up and require you to replace the well pump.
If a well runs dry with a jet pump the jet pump will also go bad and the impeller will also likely melt if it's plastic.
To make sure your well doesn't run dry you should conserve water during drought conditions and monitor your water wells level.
You can remove the water well cap if you have a drilled well and measure the static water level to see how much water you have.
If your area is under drought only use water when you need too such as for showering, bathing, laundry, dishes etc and avoid washing your car, watering lawns etc.
Deep wells are unlikely to go dry but they still can but it's more common for shallow wells to go dry than deeper wells.
In some cases drilling your well deeper can get you more water and even hydro fracking the well can help the low yield water well increase the flow.
A well can run dry in a drought especially if the well is a shallow well that is 25 feet to 50 feet or less than 100 feet deep.
Deeper wells such as 100 feet deep or 200 feet to 300 feet or more rarely run dry even in droughts although it can be possible.
The length of time it takes a dry well to recover can vary from well to well depending on how much rain and precipitation your area gets and how deep or shallow your well is.
Shallow wells typically recover and fill back up within a few weeks to a month or two once you get enough rain.
However if it does not rain or snow then the well will usually not recover until you get some rain or snow as it also takes some time for the water to seep into the ground.
Deep wells can also take longer to recover as it takes longer for rain and snow to seep down deep enough so it may take 6 months to a year for the deep well to recover if you get enough rain.
If you do have a very deep well then it's rare for them to go dry but shallow wells less than 100 feet or 25 feet deep wells are more prone to go dry than deeper wells.
A well can run dry from no rain especially if the well is a shallow well.
Most deep wells that are 100 feet deep or more rarely run dry even without rain as the water will usually still be in the ground and travel from other locations that have had rain or even when it still has no rain.
The water table may drop as well as the static water level in deep wells but they rarely go dry.
You can tell if a well is drying up by measuring the static water level in the well with a measuring tape and a weight.
The weight on the measuring tape will help you measure down to the well and find the depth of the water at the static level.
The static water level is the level of water from the top of the ground down to the top of the water.
You can also measure the depth of the water itself in the well casing to see if it's drying up.
If it has less than a 3 feet of water in the well then it may be going dry or could be a low producing well.
Other signs of a well drying up are color or taste or smell changes in the water. muddy, gritty or sandy water and water production slowing down.
With enough rain and precipitation a dry well can fill back up within a month or two or sometimes less.
If the well is deeper than it may fill back up sooner as the water moves through the soil and rocks underground from other areas away from the well.
If the well is shallower and you have mostly sandy and gravel based soil then the water may seep into the ground and fill the dry well back up within a month or less if you get lots of rain.
If the area is not getting enough rain then it may take months or years for the well to fill back up and you may need to drill the well deeper to access more water.
The length of time it takes a dry well to recover depends on the depth of the well and how much rain or snow your area gets and the soil type.
It can take rain or snow around 1 year to reach 10 feet deep in some locations and others the rain and snow may seep into the ground in as little as a few months to a year.
If you get lots of rain then the dry well will sometimes recover in a month or two or less.
Shallow wells will recover with rain and snow sooner than deeper wells.
A dry well will most often come back with some rain or snow.
When a well goes dry it does not always mean that it will never produce water again and sometimes the well going dry is from lack of rain, snow or other precipitation and due to drought conditions.
If you live in an area that gets little rain or precipitation and your well is 50 feet deep or less then it is more likely to go dry the more you pump water out of it.
Deeper wells can also go dry but are less likely to go dry from drought.
It's best to have a 100 foot or deeper well to have access to plenty of water and in locations that get plenty of rain the well will likely never go dry.
Shallow wells are more prone to go dry than deeper wells are.
In some cases a well may also go dry and only need hydro fracking to allow more water through.
And sometimes a well simply needs to be drilled deeper to access more water.
If your well goes dry then sometimes just waiting for it to recover can be good enough but if you have the money and need to drill deeper or hydro frack the well then that is another option.
If your well is deep enough to allow you to place the pump deeper than that is also another option.