New Water Well Drilling Around the Lake of the Ozarks

A new well is usually the single largest piece of infrastructure on a rural lot, and most of it ends up underground where nobody can inspect it later. This page walks through how a well is planned and built so you know what you are paying for and what questions to ask.

Where the planning starts

What the water is for. A full-time household, a weekend cabin, a shop, livestock or irrigation each need different amounts of water. Tell us what you plan to use it for, now and later, because that decides how much the well needs to deliver.

Where the property is. Missouri divides the state into drilling areas based on geology, and each area has its own construction requirements, such as how much casing is needed. ^[1] Around the Lake of the Ozarks the bedrock is mostly dolomite and limestone, and water sits in fractures and openings that are not spread evenly. ^[2] Land within a quarter mile of the lake's deeper water falls in its own drilling area, with its own requirements. ^[3]

What nearby wells found. Records for nearby wells in the state's WIMS database are the best guide to a realistic depth range. ^[4] They set expectations; they do not guarantee your result. More on that under well depth and records.

Choosing the well location

The spot has to work for both the state's rules and the drilling rig:

• Setbacks. Missouri's construction rules set minimum distances between a private well and sources of contamination: for example 50 feet from a septic tank, and 100 feet from a lateral field, a residential lagoon or an unplugged abandoned well. ^[3] On a small lake lot those distances can decide where the well goes.
• Access. A drilling rig and support truck need a path onto the lot and room to set up. Trees, slopes, docks and soft ground all matter.
• Future use. Leave room to reach the wellhead for later pump work, and keep the well away from where a driveway, building addition or fill might go.

Drilling, casing and sealing

Anyone hired to drill a well in Missouri must hold a state well installation permit, and every well must be built to the state's construction standards. ^[5] The parts that matter most to you:

• Casing lines the upper part of the hole so it stays open and keeps loose soil and shallow water out.
• Grout fills the space between the casing and the rock. It seals the well so surface water cannot run down the outside of the casing into the aquifer.
• The wellhead finishes at least 12 inches above the ground surface with a proper cap, so rainwater and runoff cannot pool at the top of the well. ^[3]

Depth is decided in the hole, not in advance. The well continues until it reaches enough water to meet the need agreed at the start, which is why a quote explains which costs depend on the final depth.

Pump, pressure tank and connection

Once the well is finished and its output is known, the pump is sized to the depth and to what the well actually produces. A pressure tank and pressure switch then let the system deliver steady pressure without the pump starting every time a tap opens. Pump installation is regulated work in Missouri too: anyone hired to install a pump must hold a state permit. ^[5]

Testing before you drink the water

A new well is disinfected after construction, and its water should be tested before anyone drinks it. Testing a private well is the owner's responsibility. Missouri's health department recommends testing at least once a year, and any time the well is serviced or the water changes in look, smell or taste. ^[6] Sample kits for the state public health laboratory are available through local public health agencies. ^[7]

Questions worth asking any well contractor

• Can I see your Missouri permit number? You can check it in WIMS yourself.
• Which parts of the quote are fixed, and which depend on the final depth?
• How much casing does this drilling area require?
• Where will the well go, and what setbacks decided that spot?
• Who files the well record with the state when the well is finished?