Well drilling costs $25 to $65 per foot of depth or $3,750 to $15,300 on average. Digging a shallow well costs $1,800 and $3,000. Costs depend on the depth drilled, soil conditions, and the well's diameter.

A water well takes 1 to 3 days to drill, depending on the depth to water, drilling diameter, ground conditions, and weather. Getting equipment to the job site, drilling, setting up a pump system, running electricity, and testing the water takes 7 days for the entire process.

There are various methods well companies use to determine the best location and depth to drill for water:

• Records and maps – Many states have water well records and water availability maps showing the depths, quality, and flow of local wells.
• Federal surveys – The U.S. Geological Survey (USGS) publishes groundwater data and maps showing water table levels and aquifer levels in the region.
• Seismic testing – Seismic imaging technology can determine the location, depth, and yield (GPM) of local aquifers.

Residential water wells are typically drilled 100 to 300 feet deep, although the rule is to drill until you hit water. The proper depth to drill depends on the underground water levels in your area. Local well drillers and neighbors can give you a general idea of how deep to drill.

Winter is the best time to drill a well due to the cold, hardened ground. Wells can be drilled year around, but well companies avoid drilling in wet conditions when the ground is muddy and unstable.

Start by searching our list of well drillers, then compare reviews and costs. Next:

• Get at least three estimates to compare.
• Ask for recommendations from family, friends, and neighbors.
• Request references and ask to see a portfolio of their previous work.
• Browse their reviews on HomeGuide and Google.
• Check the National Ground Water Association (NGWA) to ensure the contractors are certified.
• Select companies that are licensed, insured, bonded, and have been in business for more than five years.
• Get a detailed estimate, contract, and warranty in writing before the work begins.
• Never pay in full before the project starts. Follow a payment plan for work completed.

When hiring a well service, ask them the following questions:

• How deep are wells in this area?
• How much will my new well cost to drill?
• What steps will you take to ensure there is water below the drill site?
• If you drill and do not find water, do you cover the expense of re-drilling?
• How long have you been in business?
• How many wells have you installed?
• Can you provide references and a portfolio showing your work?
• Are you licensed, bonded, and insured?
• Does the estimate include the well pump, casing, pressure tank, and everything else needed to operate?
• What additional costs should I expect?
• What permits do I need, and will you obtain them?
• How long will the installation take?
• How many people will be working on the project?
• Is a warranty included, and if so, what does it cover?