To check the depth of your well you can take a long string or small rope and tie a weight to the string or rope and then lower the weight and string or rope into the well slowly until it hits the bottom of the well.
Then when the weight hits the bottom of the well take up the slack and make the string or rope at ground level of the well and that will be the depth of the well.
You can then measure the string or rope to see how deep the well is.
The cost to drill a well deeper ranges from $3,000.00 to $6,000.00 depending on how much deeper you need to go with your well.
The average cost per foot of well drilling ranges from $35.00 per foot to as much as $85.00 per foot depending on the soil conditions and if there's any rocks or other obstacles around in the area.
Drilling through rock is gonna cost more per foot and take longer than drilling through sand and dirt or clay.
Another way to increase water production of your water well is through hydrofracturing which is cheaper and ranges in cost from $1,500.00 to $3,000.00 depending on the depth of your water well.
Sometimes you might also have to have a new well drilled in a new location but sometimes you can simply drill the well down deeper to get more water.
Some water wells are only 50 foot to 150 foot and some water wells go as deep as 1,000 foot to as deep as 3,000 feet depending on location.