A new well in Grimes County, TX typically costs about $8,300 to $18,300 in 2026 for a complete system, because the median new household well filed with the state since 2016 is 295 feet deep. A shallower well near 215 feet runs about $6,000 to $13,300.
Grimes County, around Navasota, Anderson, Plantersville, Iola, Bedias, and Todd Mission, sits between the Brazos River and the Sam Houston National Forest, where many rural homes outside a water supply corporation’s lines rely on a private well. Below are the real local depths from state well records, the water-quality issues to plan for, the permit rules, and a free way to reach a licensed local driller.
How deep are wells in Grimes County?
Most new household wells in Grimes County are 215 to 370 feet deep, with a median of 295 feet. That comes from 1,179 new domestic wells drillers reported to the state from 2016 through October 2026 in the TWDB Submitted Driller’s Report database.
| Measure (new domestic wells, 2016 to 2026) | Grimes County |
|---|---|
| Wells in the sample | 1,179 |
| Typical depth range (middle half) | 215 to 370 ft |
| Median depth | 295 ft |
| Shallowest 10% / deepest 10% | under 165 ft / over 440 ft |
| Median static water level | 90 ft below ground |
| Median pump setting | 200 ft |
| Median tested yield | 35 gallons per minute |
Static water sits about 90 feet down in a typical Grimes County well, so the pump is usually set around 200 feet to ride out dry summers.
Which aquifer will my Grimes County well tap?
Your well will most likely draw from the Gulf Coast Aquifer across most of the county, with older sands to the north. The TWDB Grimes County water planning summary lists the Gulf Coast Aquifer for most water systems and the Carrizo-Wilcox and Sparta for some.
That mix is why Grimes County depths spread wider than in neighboring Waller County; ask your driller which formation wells near your land finish in.
How much does it cost to drill a well in Grimes County?
Plan on about $8,300 to $18,300 for a complete well at the 295-foot median depth. Angi’s 2026 guide puts Texas well drilling at $28 to $62 per foot (Angi), and HomeGuide puts a complete installation, including casing, pump, wiring, and permits, at $30 to $80 or more per foot (HomeGuide). These are estimates from national cost guides applied to local depths, not local quotes.
| Well depth | Estimated 2026 cost at $28 to $62/ft |
|---|---|
| Shallow (215 ft) | $6,000 to $13,300 |
| Median (295 ft) | $8,300 to $18,300 |
| Deep (370 ft) | $10,400 to $22,900 |
Budget separately for water treatment. HomeGuide lists well-water filtration systems at $800 to $4,000 and water softeners at $1,200 to $3,800. Budget for the Bluebonnet GCD’s $100 well log deposit, which is refundable. For how the line items break down, see what it costs to drill a well in Texas. If your pump ever needs replacing, here is Texas well pump replacement cost.
Worked example: a 295-foot well at $40 per foot is $11,800. Drilling only to 215 feet at the same rate would save about $3,200 up front, but only if the shallower zone gives enough good water. Ask the driller what nearby wells at that depth produced before you choose.
What water quality problems are common in Grimes County wells?
In the Sparta, TWDB says water near the outcrop is usually fresh, averaging about 300 mg/L dissolved solids, but excess iron is common (TWDB). Gulf Coast Aquifer water in this region is generally under 500 mg/L (TWDB).
In the Gulf Coast sands, arsenic is worth a test. A U.S. Geological Survey study of 91 Houston-area supply wells in the Evangeline and Chicot aquifers found arsenic from 0.58 to 23.5 micrograms per liter, with a median of 2.7, so most wells were well under the federal limit of 10 but some were over it (USGS SIR 2015-5071). A later USGS survey of the whole Texas Gulf Coast aquifer system found arsenic and manganese were the only trace elements above human-health benchmarks (USGS Fact Sheet 2020-3010).
For reference, the EPA’s secondary (non-health) guidelines are 0.3 mg/L for iron, 250 mg/L for sulfate and chloride, 500 mg/L for dissolved solids, and a pH of 6.5 to 8.5 (EPA). The Texas Well Owner Network guide recommends testing a new well and retesting yearly. If you plan a tankless water heater, read tankless water heaters on well water.
Do I need a permit to drill a well in Grimes County?
Grimes County is covered by the Bluebonnet Groundwater Conservation District, which takes in Austin, Grimes, Walker, and Waller counties. A well used for domestic use on a single tract does not need an operating permit, but it must be registered and the district must authorize drilling before work starts (Bluebonnet GCD rules). There is no registration or application fee for an exempt well, and an approved application is good for one year. The district does take a $100 well log deposit, refunded in full if the driller’s log and paperwork arrive within 60 days of completion, or $50 back between 60 and 120 days (fee schedule effective October 1, 2025). New wells must meet TDLR’s state spacing rules.
Statewide, anyone who drills a water well or installs a well pump must hold a license from the Texas Department of Licensing and Regulation (TDLR), the well must meet TDLR’s minimum distances from septic systems and other contamination sources, and the driller files a State Well Report for every new well. Those reports are the records behind the depth table above. Septic (OSSF) permits are separate; see aerobic vs conventional septic in Texas.
What should I ask a driller before I hire?
- Are you licensed by TDLR as a water well driller and pump installer? (Check the number at the TDLR license search.)
- What depth have your last few wells near my property reached?
- How do you price it: per foot, or a package with casing, pump, tank, and wiring included?
- Which formation will you finish in, and will you test for iron and arsenic after development?
- Will you file the Bluebonnet GCD registration and wait for drilling authorization?
- What happens if the first hole does not produce enough water?
If the well tests low, a storage tank can smooth it out; see storage tanks for low-yield wells. For outages, see sizing a generator for a well pump.
Get matched with a Grimes County well pro
Tell us about your project and we will pass it to a licensed local driller who works in Grimes County. Offsprig is paid by the contractor, never by you.
Related Texas well guides
Common questions
Most complete wells in Grimes County should land around $8,300 to $18,300 in 2026, based on the 295-foot median depth of new domestic wells in state records and Angi’s $28 to $62 per foot Texas range. Treatment and district fees are extra.
The median new household well reported to the state from 2016 to 2026 in Grimes County is 295 feet deep, and the middle half range from 215 to 370 feet. Median static water level is about 90 feet, per the TWDB Submitted Driller’s Report database.
You don’t need a permit for a household well in Grimes County, but the Bluebonnet GCD must register it and authorize drilling first. Registration is free, and the district holds a $100 well log deposit that is refunded when the driller files the paperwork within 60 days.
Most use the Gulf Coast Aquifer, while some northern wells and suppliers use older sands such as the Sparta or Carrizo-Wilcox, per the TWDB county summary. The Sparta is usually fresh but often high in iron. Your driller can tell you which one nearby wells reach.
Sources: depth, water level, yield, and pump data are Offsprig’s analysis of the TWDB Submitted Driller’s Report download (pulled October 2026; new wells with proposed use “Domestic,” completed 2016 or later). Water-quality figures come from the TWDB and district reports linked above; older studies reflect conditions when sampled. Costs are estimates from Angi and HomeGuide 2026 per-foot ranges, not quotes. Always confirm current rules with TDLR and your groundwater district.
Updated October 2026 · By Paul Michael