Bolthole Index

Karnes County, Texas

Building permits, zoning and land rules in Karnes County, Texas

56Index Score / 100
#111 of 254 in Texas

Unincorporated Karnes County, Texas does not list a general residential building permit, but we could not confirm whether the Commissioners Court has adopted separate residential construction or inspection rules12. The county Permitting Department does administer OSSF septic permits, beginning with a Determination Development Permit Application, and road-and-bridge permits345. Platted subdivisions can also trigger lot-size, floodplain and driveway requirements67.

At a glance

Building permit
No general residential permit is listed for unincorporated Karnes County; confirm any project-specific requirement with the Permitting Department1
Zoning
None; Karnes County has no zoning ordinance and no general authority to adopt one8910
Septic (OSSF) permits
Karnes County Permitting Department, an OSSF Authorized Agent under TCEQ; a Determination Development Permit Application comes first34
RV / tiny home / manufactured home living
No county zoning rule sets occupancy limits in unincorporated areas; septic, subdivision and private restrictions can still matter911
Minimum lot size
No countywide minimum outside subdivisions; inside a platted subdivision, 0.5 to 2 acres depending on water/septic service96
Driveway access
A Driveway Permit from the county is required before connecting to a publicly dedicated road in a subdivision; county roads generally go through Road & Bridge permits7
Well permits
Reviewed by the Evergreen Underground Water Conservation District; wells under 25,000 gallons/day must register but don't need a production permit12
Owner-builder
No county-specific permit or inspection exemption was confirmed; state law only provides a conditional exception from an inspection-notice penalty13

Who to call

Septic permits

Karnes County Permitting Department - Special Projects/Septic Permits

OSSF (septic) permit applications, including the required Determination Development Permit Application, for Karnes County

830-780-3511

[email protected]

210 W Calvert Ave. Suite 155, Karnes City, TX 78118

Online permits →

Roads & driveways

Karnes County Permitting Department - Road & Bridge Permits

Road & Bridge permits for work affecting county roads and rights-of-way in Karnes County

830-780-3511

[email protected]

210 W Calvert Ave. Suite 155, Karnes City, TX 78118

Online permits →

Contact details are copied from each office’s official page and were checked against it on September 28, 2026.

Do you need a building permit in Karnes County, Texas?

Karnes County's Permitting Department lists development-determination, OSSF septic, floodplain and road-and-bridge work, but it does not list a general residential building permit for unincorporated land1. Texas gives counties only conditional residential and fire-code authority, and residential standards require a county resolution or order before they apply2. We could not confirm whether Karnes County adopted such a resolution or order, so ask the Permitting Department whether a project-specific building review or inspection applies before construction1. A platted subdivision can separately trigger county rules for minimum lot size, mapped flood hazards and driveway access even when no general home-building permit is listed6147. An owner-builder should not treat state law as a blanket exemption: the verified provision only excuses a qualifying owner-builder from an inspection-notice penalty, and only where the underlying state subchapter applies13.

Who handles permits in Karnes County, and how do you reach them?

Karnes County's Permitting Department is the practical first call because its official page has separate Special Projects/Septic Permits and Road & Bridge Permits sections155. Reach the department at 830-780-3511 or visit 210 W Calvert Ave. Suite 155, Karnes City, TX 7811815. Office hours are 8:00 am to 5:00 pm Monday through Friday, with a closure from 12:00 to 1:0015. Development and road applications are linked through the county permit portal155. For septic work, submit a Determination Development Permit Application before the OSSF application4. Because the county page does not identify a general residential building office, use the same department to confirm whether your particular location, subdivision or project triggers another county approval1.

Does Karnes County have zoning?

Karnes County has no confirmed county zoning ordinance for unincorporated land, and Texas law grants county zoning authority only in limited geographic or subject-specific situations810. As a result, unincorporated Karnes County has no county zoning rule setting minimum dwelling size, setbacks, lot coverage or building height9. The same zoning answer applies to accessory dwellings, RV occupancy, tiny-home occupancy, manufactured-home occupancy and temporary camping, but septic rules, subdivision plats, deed restrictions and municipal rules can still control a particular property911. In county-governed subdivisions, standard spacing requires 1 acre for public water with conventional septic or a private well with public sewer, and 2 acres for a private well with conventional septic; dense spacing can allow smaller lots6. Qualifying agricultural, ranch, wildlife-management or timber-production divisions may be exempt from platting if every stated condition is met16.

How do septic permits work in Karnes County?

Every OSSF (on-site sewage facility, commonly called a septic system) built, altered, extended or repaired in Karnes County needs a permit, and the county's Permitting Department requires a Determination Development Permit Application before it will accept the OSSF application itself411. Statewide, Texas offers a narrow 10-acre exemption from OSSF permitting, but only if every condition is met: a licensed site evaluator or engineer signs off, the tract is at least 10 acres, the dwelling is the only one on the tract, every part of the system stays at least 100 feet from the property line, and effluent stays on the property11. Emergency repairs don't need a permit in advance, but must be reported in writing within 72 hours after the repair begins11. Soils here make planning worthwhile either way: only 15.2% of Karnes County's land is free of severe limitations for a conventional drain field, so expect many properties to need a site evaluation and possibly an alternative system17. For water, know that Karnes County sits entirely within the Evergreen Underground Water Conservation District: any new well needs District review before drilling, and while a well producing less than 25,000 gallons a day (about 17.5 gallons per minute) is exempt from a production permit, it still must be registered with the District12.

Can you live in an RV or tiny home on your land in Karnes County?

Unincorporated Karnes County has no county zoning rule that limits RV, tiny-home or manufactured-home occupancy, and county zoning sets no minimum dwelling size9. That answers only the county-zoning question: an RV or tiny home still needs a lawful sewage solution, and constructing, altering, extending or repairing an OSSF generally requires a permit11. Platted-subdivision requirements and private deed restrictions may also affect placement or use, while property inside a city can be subject to municipal rules18. We could not confirm a Karnes County certificate-of-occupancy rule or a county residential inspection program, so ask the Permitting Department about occupancy approval before relying on the absence of zoning1. For a factory-built modular home, Texas's industrialized-housing program applies statewide codes to regulated modules and components19.

What are the steps to build a home in Karnes County?

  1. Confirm whether the parcel is inside a city, a municipal extraterritorial jurisdiction or a platted subdivision, because the approval path changes by location18.
  2. Ask the Karnes County Permitting Department whether the project triggers any residential construction, floodplain or development approval; no general home-building permit is listed, but adoption of a separate residential rule was not confirmed12.
  3. Order the septic site evaluation early because only 15.2% of county soils avoid severe limits for a conventional drain field17.
  4. File the Determination Development Permit Application, then the OSSF application, unless the complete state septic exemption applies411.
  5. Have a new well reviewed by the Evergreen Underground Water Conservation District before drilling12.
  6. Obtain a subdivision Driveway Permit for access to a publicly dedicated road, or contact Road & Bridge Permits for county-road work75. A state-highway driveway instead requires the TxDOT process20.

What should you check before buying land in Karnes County?

Water and soils deserve real attention here: annual precipitation averages just 31 inches, with severe drought in 23.5% of years, and only 15.2% of soils are free of septic limitations, so budget for both a well application through the Evergreen Underground Water Conservation District and a careful septic site evaluation21221712. Terrain is not the constraint: 99.3% of the county sits at 15% slope or less, though only 13% is wooded, so shade and windbreaks are limited2324. Check FEMA flood maps before you buy, since floodplain rules apply to subdivision development and likely to construction generally near mapped hazard areas14. If the tract you're buying was recently split off a larger parcel in a subdivision, confirm it went through the county's plat process or qualified for an exception, since that affects lot size, road access and driveway permitting167. Typical property tax runs about 1% effectively, with a median bill near $1,344 a year, against a typical home value around $220,444252627.

Watch-outs

  • We could not confirm whether Karnes County requires a certificate of occupancy, has adopted residential construction standards or performs general home inspections, so ask the Permitting Department before work begins12.
  • Subdivision rules add real requirements that don't apply to a raw unplatted tract: minimum lot size, floodplain plat details, and a Driveway Permit before connecting to a subdivision's public road, so check whether your land is platted before assuming the county's hands-off approach applies in full67.

Sources

  1. Karnes County Special Projects & Permits (2026 county census)
  2. Local Government Code Chapter 233, County Regulation of Housing and Other Structures (Texas statewide rule), quoted and re-checked
  3. Karnes County Texas — Permitting Department (2026 county census)
  4. Karnes County Texas — Permitting Department, quoted and re-checked
  5. Karnes County Permitting Department - Road & Bridge Permits (co.karnes.tx.us)
  6. Karnes County Subdivision and Development Rules and Regulations, quoted and re-checked
  7. Karnes County Subdivision and Development Rules and Regulations, quoted and re-checked
  8. Karnes County Special Projects & Permits (2026 county census)
  9. Texas law on county zoning and building authority
  10. Local Government Code Chapter 231, County Zoning Authority (Texas statewide rule), quoted and re-checked
  11. Karnes County Texas — Permitting Department, quoted and re-checked
  12. What We Do — Evergreen Underground Water Conservation District, quoted and re-checked
  13. Local Government Code Chapter 233. County Regulation of Housing and Other Structures, quoted and re-checked
  14. Karnes County Subdivision and Development Rules and Regulations, quoted and re-checked
  15. Karnes County Permitting Department - Special Projects/Septic Permits (co.karnes.tx.us)
  16. Karnes County Subdivision and Development Rules and Regulations, quoted and re-checked
  17. Share of soils without severe limits for a conventional septic drain field (USDA SSURGO): Bolthole Index county data
  18. Karnes County Subdivision and Development Rules and Regulations, quoted and re-checked
  19. Industrialized Housing and Buildings – Adoption of New Code Editions (Texas statewide rule), quoted and re-checked
  20. Section 4: Driveway Permits, Design, and Materials (Texas statewide rule), quoted and re-checked
  21. Annual precipitation: Bolthole Index county data
  22. Share of years in severe drought: Bolthole Index county data
  23. Share of land at 15% slope or less: Bolthole Index county data
  24. Wooded share of land: Bolthole Index county data
  25. Effective property tax rate: Bolthole Index county data
  26. Median property tax bill: Bolthole Index county data
  27. Typical home value (Zillow): Bolthole Index county data

Written September 28, 2026 from the rules quoted below, each taken from an official source and re-checked by an independent reviewer. This is research, not legal advice: rules change, so confirm with the office before you buy or build.

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County locator

Karnes County in Texas

56
County map
Karnes County highlighted among the Texas counties · colored by Index score

How Karnes County scores

Seclusion55100% ev.
Self-Sufficiency3198% ev.
Admin Boringness8290% ev.
Durability38100% ev.
Property Autonomy71100% ev.
Carry Cost80100% ev.

Evidence strength: 98%. This reports direct-source completeness and fallback use; it is separate from the score and is not a confidence interval. How it works →

$220kTypical home
1%Property tax
$2,951Land / acre
31"Annual rain
23.5% of yrsSevere drought
46 / yr (+30.3)Mid-century 100°F days
27.1 daysMid-century dry spell
2.22" (+5.4%)Mid-century 1-day rain
1.4×Wildfire change factor
100%Forward climate coverage
$2,052Home insurance / yr
0.6% / yrInsurance growth
0%Nonrenewal rate
county median (2+ published ZIPs)Insurance basis
15,040People within 30 min
5,014,934People within 2 hr
12,460Radius comparison (15 mi)
20.1People / sq mi
0%Federal land
99.3%Land at 15% slope or less
15.2%Septic soil without severe limits
72,208 acWorkable land screen
13%Wooded land
9 tonsBiomass / forest ac
70.5°FAvg temp

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Answers from the rulebook for Karnes County

What the ordinances and state agencies actually say — one answer per question, each quoted from the official source and independently re-checked.

Karnes County rules

  • Zoning districts · by state lawNo county rule

    Unincorporated Karnes County: no county rule sets this, because Texas law gives zoning power only to certain counties, and Karnes County has no zoning ordinance. The county legal census found no county zoning ordinance, citing co.karnes.tx.us.

    • Septic, floodplain, subdivision and health rules still apply; cities and towns set their own rules inside their limits.
    • Chapter 231 does not grant a general statewide county zoning power; authority is provided through geographically or subject-matter limited subchapters.
    • For Padre Island, the authority applies in Cameron or Willacy County outside a municipality and within two miles of a publicly owned park or recreational development, or within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.
    “This subchapter applies to the areas of Padre Island located in Cameron or Willacy County and located: (1) outside a municipality but within two miles of a publicly owned park or recreational development; or (2) within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.”
  • Minimum dwelling size · by state lawNo county rule

    Unincorporated Karnes County: no county rule sets this, because Texas law gives zoning power only to certain counties, and Karnes County has no zoning ordinance. The county legal census found no county zoning ordinance, citing co.karnes.tx.us.

    • Septic, floodplain, subdivision and health rules still apply; cities and towns set their own rules inside their limits.
    • Chapter 231 does not grant a general statewide county zoning power; authority is provided through geographically or subject-matter limited subchapters.
    • For Padre Island, the authority applies in Cameron or Willacy County outside a municipality and within two miles of a publicly owned park or recreational development, or within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.
    “This subchapter applies to the areas of Padre Island located in Cameron or Willacy County and located: (1) outside a municipality but within two miles of a publicly owned park or recreational development; or (2) within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.”
  • Minimum lot sizeSpecified

    Lots in subdivisions outside the boundaries of incorporated towns or cities in Karnes County.

    • Standard lot spacing: public water and public sewer has no minimum lot size; public water with conventional septic requires 1.0 acre; an individual private well with public sewer requires 1.0 acre; an individual private well with conventional septic requires 2.0 acres.
    • Dense lot spacing: public water with conventional septic requires 1/2 acre; an individual private well with public sewer requires 1/2 acre; an individual private well with conventional septic requires 1.0 acre.

    public water and public sewer, standard lot spacing: no minimum lot size · public water and conventional septic, standard lot spacing: >= 1 acre minimum · individual private well and public sewer, standard lot spacing: >= 1 acre minimum · individual private well and conventional septic, standard lot spacing: >= 2 acre minimum · public water and conventional septic, dense lot spacing: >= 0.5 acre minimum · individual private well and public sewer, dense lot spacing: >= 0.5 acre minimum · individual private well and conventional septic, dense lot spacing: >= 1 acre minimum

    “Lots served with public water and conventional septic – 1.0 acre minimum lot size.”
  • Setbacks · by state lawNo county rule

    Unincorporated Karnes County: no county rule sets this, because Texas law gives zoning power only to certain counties, and Karnes County has no zoning ordinance. The county legal census found no county zoning ordinance, citing co.karnes.tx.us.

    • Septic, floodplain, subdivision and health rules still apply; cities and towns set their own rules inside their limits.
    • Chapter 231 does not grant a general statewide county zoning power; authority is provided through geographically or subject-matter limited subchapters.
    • For Padre Island, the authority applies in Cameron or Willacy County outside a municipality and within two miles of a publicly owned park or recreational development, or within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.
    “This subchapter applies to the areas of Padre Island located in Cameron or Willacy County and located: (1) outside a municipality but within two miles of a publicly owned park or recreational development; or (2) within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.”
  • Lot coverage · by state lawNo county rule

    Unincorporated Karnes County: no county rule sets this, because Texas law gives zoning power only to certain counties, and Karnes County has no zoning ordinance. The county legal census found no county zoning ordinance, citing co.karnes.tx.us.

    • Septic, floodplain, subdivision and health rules still apply; cities and towns set their own rules inside their limits.
    • Chapter 231 does not grant a general statewide county zoning power; authority is provided through geographically or subject-matter limited subchapters.
    • For Padre Island, the authority applies in Cameron or Willacy County outside a municipality and within two miles of a publicly owned park or recreational development, or within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.
    “This subchapter applies to the areas of Padre Island located in Cameron or Willacy County and located: (1) outside a municipality but within two miles of a publicly owned park or recreational development; or (2) within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.”
  • Building height · by state lawNo county rule

    Unincorporated Karnes County: no county rule sets this, because Texas law gives zoning power only to certain counties, and Karnes County has no zoning ordinance. The county legal census found no county zoning ordinance, citing co.karnes.tx.us.

    • Septic, floodplain, subdivision and health rules still apply; cities and towns set their own rules inside their limits.
    • Chapter 231 does not grant a general statewide county zoning power; authority is provided through geographically or subject-matter limited subchapters.
    • For Padre Island, the authority applies in Cameron or Willacy County outside a municipality and within two miles of a publicly owned park or recreational development, or within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.
    “This subchapter applies to the areas of Padre Island located in Cameron or Willacy County and located: (1) outside a municipality but within two miles of a publicly owned park or recreational development; or (2) within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.”
  • Living in an RV · by state lawNo county rule

    Unincorporated Karnes County: no county rule sets this, because Texas law gives zoning power only to certain counties, and Karnes County has no zoning ordinance. The county legal census found no county zoning ordinance, citing co.karnes.tx.us.

    • Septic, floodplain, subdivision and health rules still apply; cities and towns set their own rules inside their limits.
    • Chapter 231 does not grant a general statewide county zoning power; authority is provided through geographically or subject-matter limited subchapters.
    • For Padre Island, the authority applies in Cameron or Willacy County outside a municipality and within two miles of a publicly owned park or recreational development, or within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.
    “This subchapter applies to the areas of Padre Island located in Cameron or Willacy County and located: (1) outside a municipality but within two miles of a publicly owned park or recreational development; or (2) within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.”
  • Camping on your land · by state lawNo county rule

    Unincorporated Karnes County: no county rule sets this, because Texas law gives zoning power only to certain counties, and Karnes County has no zoning ordinance. The county legal census found no county zoning ordinance, citing co.karnes.tx.us.

    • Septic, floodplain, subdivision and health rules still apply; cities and towns set their own rules inside their limits.
    • Chapter 231 does not grant a general statewide county zoning power; authority is provided through geographically or subject-matter limited subchapters.
    • For Padre Island, the authority applies in Cameron or Willacy County outside a municipality and within two miles of a publicly owned park or recreational development, or within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.
    “This subchapter applies to the areas of Padre Island located in Cameron or Willacy County and located: (1) outside a municipality but within two miles of a publicly owned park or recreational development; or (2) within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.”
  • Tiny homes · by state lawNo county rule

    Unincorporated Karnes County: no county rule sets this, because Texas law gives zoning power only to certain counties, and Karnes County has no zoning ordinance. The county legal census found no county zoning ordinance, citing co.karnes.tx.us.

    • Septic, floodplain, subdivision and health rules still apply; cities and towns set their own rules inside their limits.
    • Chapter 231 does not grant a general statewide county zoning power; authority is provided through geographically or subject-matter limited subchapters.
    • For Padre Island, the authority applies in Cameron or Willacy County outside a municipality and within two miles of a publicly owned park or recreational development, or within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.
    “This subchapter applies to the areas of Padre Island located in Cameron or Willacy County and located: (1) outside a municipality but within two miles of a publicly owned park or recreational development; or (2) within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.”
  • Manufactured homes · by state lawNo county rule

    Unincorporated Karnes County: no county rule sets this, because Texas law gives zoning power only to certain counties, and Karnes County has no zoning ordinance. The county legal census found no county zoning ordinance, citing co.karnes.tx.us.

    • Septic, floodplain, subdivision and health rules still apply; cities and towns set their own rules inside their limits.
    • Chapter 231 does not grant a general statewide county zoning power; authority is provided through geographically or subject-matter limited subchapters.
    • For Padre Island, the authority applies in Cameron or Willacy County outside a municipality and within two miles of a publicly owned park or recreational development, or within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.
    “This subchapter applies to the areas of Padre Island located in Cameron or Willacy County and located: (1) outside a municipality but within two miles of a publicly owned park or recreational development; or (2) within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.”
  • Accessory dwellings · by state lawNo county rule

    Unincorporated Karnes County: no county rule sets this, because Texas law gives zoning power only to certain counties, and Karnes County has no zoning ordinance. The county legal census found no county zoning ordinance, citing co.karnes.tx.us.

    • Septic, floodplain, subdivision and health rules still apply; cities and towns set their own rules inside their limits.
    • Chapter 231 does not grant a general statewide county zoning power; authority is provided through geographically or subject-matter limited subchapters.
    • For Padre Island, the authority applies in Cameron or Willacy County outside a municipality and within two miles of a publicly owned park or recreational development, or within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.
    “This subchapter applies to the areas of Padre Island located in Cameron or Willacy County and located: (1) outside a municipality but within two miles of a publicly owned park or recreational development; or (2) within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.”
  • Who permits septicCounty

    OSSF permitting administration in Karnes County, including the county's Special Projects/Septic Permits function.

    • A Determination Development Permit Application is required before an OSSF application.
    • Development applications are submitted through the county permit portal.
    • The county page directs applicants to contact Special Projects for further information.
    “Special Projects/Septic Permits A Determination Development Permit Application is required prior to an OSSF application. Development applications are submitted through the permit portal.”
  • Septic permitRequired

    Construction, installation, alteration, extension, or repair of an OSSF in Karnes County.

    • Karnes County requires a Determination Development Permit Application before an OSSF application.
    • Under the statewide TCEQ rule, a permit may be exempted under the 10-acre rule only if all listed requirements are met: site evaluation by a licensed Site Evaluator or Professional Engineer; single-family dwelling on a tract of at least 10 acres; no nuisance or groundwater pollution; all OSSF parts at least 100 feet from the property line; effluent disposed of on the property; and the dwelling is the only dwelling on the tract.
    • Emergency repairs listed by TCEQ do not require a permit but must be reported in writing to the permitting authority within 72 hours after repairs begin.
    • Grandfathered systems may be exempt only if they meet TCEQ's stated pre-authorization-date or pre-September-1-1989, nuisance, repair, and alteration conditions.

    10-acre exemption tract size: >= 10 acres (All TCEQ 10-acre-rule conditions must also be met.) · OSSF setback under 10-acre rule: >= 100 feet from property line (Applies to the exemption, not necessarily every permitted system.) · Emergency-repair reporting deadline: 72 hours after repairs begin (Emergency repairs must be reported in writing to the permitting authority.)

    “A permit is required to construct, install, alter, extend, or repair an OSSF. Always check with your local permitting authority. Local permitting programs can be more stringent than State minimums.”
  • Septic inspectionLimited

    Aerobic OSSF systems permitted through Karnes County, with specific maintenance-contract requirements stated in the county OSSF form.

    • The system must be covered by a maintenance contract for the first two years.
    • After the initial two-year service agreement, an owner of an aerobic treatment system for a single-family residence must obtain a maintenance contract within 30 days or maintain the system personally.
    • Commercial aerobic treatment systems must maintain a continuous maintenance contract.

    initial maintenance-contract period: 2 years · deadline to obtain post-contract maintenance contract for single-family aerobic system: 30 days (after the initial two-year service agreement if the owner does not maintain the system personally)

    “This OSSF shall be covered by a maintenance contract for the first two years. After the initial two-year service agreement, the owner of an aerobic treatment system for a single family residence shall either obtain a maintenance contract within 30 days or maintain the system personally. All commercial aerobic treatment systems shall maintain a continuous maintenance contract.”
    One more reviewed finding on this topic
    • Required — Installation of an on-site sewage facility under the Karnes County OSSF permitting program.
      “You or your installer must contact the approving office prior to completion to arrange the required facility inspection. The authorization to construct is valid for one year from the date of issue. If a final inspection has not been performed within one year of issue, a new application and fee will be required.”
  • Well permitLimited

    Water wells in Karnes County within the Evergreen Underground Water Conservation District, whose boundaries are coterminous with Karnes County.

    • All new wells must be reviewed by EUWCD before drilling begins.
    • A well may be exempt from a production permit but must be registered with the District when it produces less than 25,000 gallons per day, approximately 17.5 gallons per minute.
    • A production permit is required before drilling or operating a well capable of producing more than 25,000 gallons per day or used for public water supply, irrigation, commercial, or industrial purposes.
    • Permitted wells must meet spacing requirements, production limits, and reporting requirements.

    production threshold for production permit: > 25000 gallons per day (Smaller exempt wells do not require a production permit but must be registered.) · approximate production threshold: > 17.5 gallons per minute (EUWCD describes this as approximately equivalent to 25,000 gallons per day.)

    “Certain wells in the Evergreen Underground Water Conservation District (EUWCD) must be registered or permitted, depending on their size and use. If your well is capable of producing more than 25,000 gallons per day (or 17.5 gallons per minute), or if it is used for public water supply, irrigation, commercial, or industrial purposes, a production permit is required before drilling or operating.”
  • Agricultural exemptionAvailable (with conditions)

    Exemptions from Karnes County subdivision platting requirements for tracts outside municipal limits.

    • Agricultural, farm, ranch, wildlife-management, or timber-production exemption: the owner must not lay out streets, alleys, squares, parks, or other parts described by Local Government Code Section 232.001(a)(3), and the land must be used primarily for the specified agricultural or production purposes.
    • Other listed exemptions include family transfers of four or fewer parts, subdivisions with all lots more than 10 acres, veteran sales through the Veterans' Land Board program, certain political-subdivision floodplain transfers, specified two-part transfers, state-owned tracts, lender-related divisions, and adjoining-landowner sales.
    • The county rules were revised 05/30/2013; that revision date is not treated as an effective date.

    agricultural exemption lot division: two or more parts (All lots must be used primarily for agricultural, farm, ranch, wildlife-management, or timber-production purposes, and no part described by Local Government Code Section 232.001(a)(3) may be laid out.) · large-lot exemption: > >10 acres per lot (The owner must not lay out a part described by Local Government Code Section 232.001(a)(3).)

    “The owner does not lay out a part of the tract described by Local Government Code Section 232.001(a) (3) Texas Local Government Code and the land is to be used primarily for agricultural use, as defined by Section 1-d, Article VIII, Texas Constitution, or for farm, ranch, wildlife management, or timber production use within the meaning of Section 1 -d- 1, Article VIII, Texas Constitution; or”
  • Subdividing landRegulated (with conditions)

    Subdivision plats and related development in areas outside the boundaries of incorporated towns or cities in Karnes County; subdivisions within a municipality's extraterritorial jurisdiction are governed according to the applicable interlocal agreement.

    • The Commissioners Court of Karnes County administers the rules and delegates initial review to the Karnes County Development Review Committee.
    • Owners who subdivide must comply with the regulations and submit an approval application.
    • No subdivision is permitted until fees are paid, required data, attachments, third-party approvals, and deficiencies are addressed; the final plat must receive Commissioners Court approval with appropriate bonds.
    • The final record plat must be recorded within fifteen working days after Commissioners Court approval or the approval is voided.
    • If the subdivision is within an incorporated municipality's extraterritorial jurisdiction, the plat is approved according to the interlocal agreement between that municipality and the County.
    • State, federal, and applicable regulations take precedence in the event of conflict.
    • Exemptions from Article II platting requirements include qualifying agricultural, farm, ranch, wildlife-management, or timber-production uses; qualifying family transfers involving four or fewer parts; divisions where all lots exceed 10 acres and no public-use area described by Local Government Code §232.001(a)(3) is laid out; qualifying Veterans' Land Board sales; qualifying political-subdivision floodplain sales to adjoining landowners; certain two-part transfers where one part is retained and the other is transferred for further subdivision; transfers to owners of undivided interests when a plat is filed before further development; qualifying state-owned land; qualifying lender-related two-part divisions with at least two acres per part, 40 feet of deeded road frontage, no third-party conveyance, and no public-use area; and qualifying two-part sales to an adjoining landowner with at least two acres remaining, 40 feet of deeded road frontage for each tract, and no public-use area.
    • A family exemption claimant must file Attachment 18 with the Karnes County Clerk contemporaneously with the deed or other conveyance instrument and provide a filed copy to the Karnes County 911 Special Projects Office.
    • A non-standard plat may be approved when full platting requirements would unfairly burden the property owner without promoting public welfare; a variance may be requested in writing before the standard plat application, except as to fees and financial guarantees.
    • Application fees are non-refundable and are set forth in Attachment 1; the Commissioners Court may amend those fees without amending the remainder of the regulations.
    • The document is marked Revised 05/30/2013; this revision notation is not treated as an effective date.

    final plat approval period: 60 days after receipt of completed plat application (Approval must be by Commissioners Court with appropriate bonds.) · recording deadline: 15 working days after Commissioners Court approval (Approval is voided if the record plat is not timely recorded.) · building setback from County right-of-way: 25 feet · side setback: 15 feet · rear setback: 15 feet · minimum embankment/back-slope easement: >= 20 feet · minimum road frontage: >= 40 feet (Lots may not be narrower than 40 feet between the road frontage and the bulk of the lot.) · minimum lot size with public water and public sewer: none · minimum lot size with public water and conventional septic: >= 1 acre · minimum lot size with individual private well and public sewer: >= 1 acre · minimum lot size with individual private well and conventional septic: >= 2 acres · dense lot spacing with public water and conventional septic: >= 0.5 acre · dense lot spacing with individual private well and public sewer: >= 0.5 acre · dense lot spacing with individual private well and conventional septic: >= 1 acre

    “Individuals recording plats that are outside of city limits and subject to County policy should review the current Karnes County Subdivision Regulations Revisions”
  • Driveway accessRequired

    Driveway access onto a publicly dedicated roadway from lots within a subdivision governed by the Karnes County subdivision rules.

    • The driveway must be constructed according to specifications stated within the permit.
    • In some cases, the developer may be required to design and construct driveways to conform to county standards.
    • The rules apply to subdivisions outside incorporated towns or cities; municipal extraterritorial-jurisdiction arrangements may apply instead.
    “no driveway constructed on any lot within this subdivision shall be permitted access onto a publicly dedicated roadway unless a Driveway Permit has been issued by the Karnes County Health and Public Safety Office. The driveway shall be constructed according to specifications stated within the permit.”
  • Building in a floodplainLimited

    Subdivision development involving mapped or identified 100-year floodplain, regulatory floodway, or FEMA Special Flood Hazard Area in areas governed by the Karnes County subdivision rules.

    • FEMA Special Flood Hazard Areas identified by the most current FEMA Flood Insurance Rate Maps must be shown on the plat.
    • Lots in the 100-year floodplain require additional contours identifying the floodplain and regulatory floodway, if any.
    • If base flood elevations have not been established, a detailed study is required under the Karnes County Flood Damage Prevention Order and the developer must submit the study results to FEMA for approval.
    • Required finished-floor elevations and drainage information must be shown or submitted where applicable.
    • These rules apply to subdivisions outside incorporated towns or cities.

    contour interval for elevation contours: <= 10 feet maximum (flood-prone areas or areas required by an engineer must be shown at 2-foot intervals) · stormwater analysis watershed threshold: > 10 acres

    “All Special Flood Hazard Areas (SFHA) identified by the most current Flood Insurance Rate Maps published by the Federal Emergency Management Agency (FEMA) shall be shown on the plat.”
  • Permit feesPublished (with conditions)

    Subdivision development fees for subdivisions outside the boundaries of incorporated towns or cities in Karnes County.

    • The listed fees are subject to change.
    • The regulations state that fees may be amended by the Commissioners’ Court without amending the remainder of the regulations.
    • These are subdivision fees, not a complete fee schedule for every county permit.

    application fee for plat without roads: per 100 USD per lot · application fee for plat with roads: 3000 + 100 per lot USD · minimum application fee for all new subdivisions: 500 USD · application fee to amend a plat: 200 USD · application fee to revise a plat: per 100 USD per lot created (plus all publication costs) · application fee to cancel a plat: per 100 USD per lot (plus all publication costs) · filing fee for final approved plat: 111 first page; 100 each additional page USD (paid to the Karnes County Clerk at filing) · application fee for non-standard plat or variance: 100 USD · Texas Veterans Exclusion Request: 100 USD · hard copy of subdivision regulations: 25 USD

    “Application fee for Plat without roads $100.00/lot Application fee for Plat with roads $3,000 + $100.00/lot Minimum application fee for all new subdivisions $500.00”
  • Permit processPartial

    Subdivision approval and OSSF permitting processes administered by Karnes County for applicable unincorporated areas.

    • The subdivision rules apply to subdivisions outside incorporated towns or cities.
    • A subdivision in a municipality's extraterritorial jurisdiction is approved according to the applicable interlocal agreement.
    • For OSSF construction, authorization must be obtained before construction and inspection must be arranged before completion.
    “A Determination Development Permit Application is required prior to an OSSF application. Development applications are submitted through the permit portal.”
  • Building permitNot required

    In unincorporated Karnes County the permitting office issues only development-determination, OSSF (septic), floodplain and road/bridge permits; Texas counties lack general authority to require or enforce a residential building code.

    Karnes County Special Projects & Permits ↗Scouted from the county site, not yet independently re-checked

  • County-wide zoningAbsent

    Texas counties have no general zoning authority over unincorporated land and Karnes County's permitting page lists no zoning program.

    Karnes County Special Projects & Permits ↗Scouted from the county site, not yet independently re-checked

Texas rules that apply here

  • Owner-builder exemptionAvailable (with conditions)

    Penalty under Texas Local Government Code Section 233.157 for failure to provide required inspection notices under Chapter 233, Subchapter F

    • This is an exception to the penalty provision, not an exemption from the underlying building-code inspection requirements.
    • The new residential construction must be built by the individual or the individual must act as the individual's own contractor.
    • The individual must intend to use the residence as the individual's primary residence.
    • The underlying Subchapter F requirements apply only in a county that adopted the required resolution or order under Section 233.152.
    “An individual who fails to provide proper notice in accordance with Sections 233.154(b) and (c) is not subject to a penalty under this subsection if: (1) the new residential construction is built by the individual or the individual acts as the individual's own contractor; and (2) the individual intends to use the residence as the individual's primary residence.”
  • Building code adoptedPartial

    Industrialized housing and buildings, modules, and modular components governed by the Texas Industrialized Housing and Buildings program.

    • The mandatory state code adoption applies to industrialized housing and buildings, modules, and modular components, not all construction statewide.
    • The effective date is July 1, 2024.
    • The International Existing Building Code applies to alterations of portable industrialized buildings.
    • Manufacturers already certified for Texas must have design-package documents reviewed and approved to the new editions with an approval date on or after July 1, 2024, unless the manufacturer elected to transition before the effective date under Department rule 70.70(a)(5)(B).
    • Construction begun on or after July 1, 2024 must comply with the new code editions and approved design packages.
    • Construction begun before July 1, 2024, or before a manufacturer's effective transition date, must meet the stated completion, inspection, and labeling deadline to remain eligible for a Texas decal.

    effective date: 2024-07-01 · International Building Code: 2021 Edition (including appendices C, F, and K) · International Residential Code: 2021 Edition (including appendices AG, AH, AK, AP, AQ, and AT) · International Fuel Gas Code: 2021 Edition · International Mechanical Code: 2021 Edition · International Plumbing Code: 2021 Edition · International Energy Conservation Code: 2015 Edition · National Electrical Code: 2020 Edition · International Existing Building Code: 2021 Edition (for alterations of portable industrialized buildings)

    “July 1, 2024, all industrialized housing and buildings, modules, and modular components shall comply with the following codes, as amended in §70.101 of the IHB Rules:”
  • Off-grid sanitationLimited

    Domestic sewage treatment and disposal through an OSSF rather than centralized sewer service in Karnes County.

    • An OSSF generally requires a permit before construction, installation, alteration, extension, or repair.
    • The TCEQ 10-acre exemption and emergency-repair exception apply only when all stated conditions are met.
    • Any applicable Karnes County requirements may be more stringent than state minimums.
    • OSSFs can handle only domestic sewage; industrial or hazardous waste cannot enter an OSSF.
    “OSSFs can handle only domestic sewage. Industrial or hazardous waste cannot enter an OSSF; this waste will be treated in the soil and will ruin an OSSF by literally killing the bacteria that break down the biosolids.”
  • county zoning authorityLimited

    Texas counties adopting zoning regulations for specified unincorporated or otherwise specially defined areas.

    • Chapter 231 does not grant a general statewide county zoning power; authority is provided through geographically or subject-matter limited subchapters.
    • For Padre Island, the authority applies in Cameron or Willacy County outside a municipality and within two miles of a publicly owned park or recreational development, or within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.
    • Other Chapter 231 subchapters address special areas including the Amistad Recreation Area in Val Verde County, military zones, certain lakes, the El Paso Mission Trail Historical Area, Lake Somerville, and Falcon Lake in Zapata County.
    • The cited statute was enacted effective September 1, 1987; the Falcon Lake subchapter was added effective June 15, 2007, and amended effective September 1, 2009.

    Padre Island distance from publicly owned park or recreational development: <= 2 miles (Area must be outside a municipality and in Cameron or Willacy County.) · Padre Island distance from beach, wharf, or bathhouse: <= 2 miles (The beach, wharf, or bathhouse must be used by at least 500 persons annually.)

    “This subchapter applies to the areas of Padre Island located in Cameron or Willacy County and located: (1) outside a municipality but within two miles of a publicly owned park or recreational development; or (2) within two miles of a beach, wharf, or bathhouse used by at least 500 persons annually.”
  • county building authorityLimited

    Texas counties adopting and enforcing fire-code building permits for specified buildings in unincorporated areas and applying residential building-code standards in certain counties.

    • Under Section 233.061, the county must have a population over 250,000 or be adjacent to a county with a population over 250,000.
    • Under Section 233.062, the fire code applies only to commercial establishments, public buildings, and multifamily residential dwellings consisting of four or more units constructed in an unincorporated area.
    • The fire code does not apply to an industrial facility having a fire brigade that conforms to Occupational Health and Safety Administration requirements.
    • A covered applicant must submit a plan and a commissioners-court-set application fee; the county must issue or deny the permit within 30 days, and failure to act within 30 days approves the construction for purposes of the subchapter.
    • The fire code must conform to the International Fire Code or Uniform Fire Code as those codes existed on May 1, 2005, or establish protective measures exceeding those standards; later editions may be adopted.
    • Residential standards under Section 233.152 apply only if the county adopts a resolution or order and the county is within 50 miles of an international border or has a population over 100.
    • Those residential standards apply only to new single-family-house or duplex construction beginning after September 1, 2009; manufactured or modular structures governed by Occupations Code Chapters 1201 or 1202 are excluded from the definition of new residential construction.
    • A municipality's building code controls in its extraterritorial jurisdiction, and Section 233.152 does not authorize county prior approval of new residential construction or county zoning regulations.
    • Fire-code inspection and permit fees may be charged under a fee schedule based on building type, limited to amounts necessary to administer and enforce the subchapter; inspection fees must be reasonable and reflect approximate inspection costs.

    county population threshold for fire-code authority: > 250000 persons (A county adjacent to a county over 250,000 also qualifies.) · multifamily residential dwelling threshold: >= 4 units (The fire code applies only to covered buildings constructed in an unincorporated area.) · residential-code border distance: <= 50 miles (Alternative qualification is county population over 100.) · application decision period: 30 days (If the commissioners court does not issue or deny the permit within 30 days after receiving the application and fee, construction is approved for purposes of the subchapter.) · residential standards effective construction date: > 2009-09-01 (Applies only to new residential construction that begins after September 1, 2009.)

    “The commissioners court of a county with a population of over 250,000 or a county adjacent to a county with a population of over 250,000 may adopt a fire code and rules necessary to administer and enforce the fire code. [...] The fire code applies only to the following buildings constructed in an unincorporated area of the county: (1) a commercial establishment; (2) a public building; and (3) a multifamily residential dwelling consisting of four or more units.”

Still unanswered

We looked and could not find an official answer yet. Silence is not permission — ask the county directly.

  • Inspections — Building inspections for residential construction in Karnes County, including unincorporated areas.
  • Certificate of occupancy — Certificates of occupancy or equivalent occupancy approvals in Karnes County
  • Local zoning — Aggregate local-zoning status within Karnes County, including possible municipal zoning and any county zoning applicable to unincorporated areas.
  • Mandatory utility hookup — Connection to centralized water or wastewater utilities for property in Karnes County.
  • Short-term rentals — Short-term rental use of residential property in unincorporated Karnes County.

Each answer was extracted from an official source and independently re-checked against that source by a second reviewer. That is an evidence check, not legal advice. Rules change; confirm with the authority before you buy or build.

Living off-grid in Karnes County, Texas

Is Karnes County a good place to live off-grid or homestead?

Karnes County scores 56/100 on the Bolthole Index, a solid county profile. Its strengths: low administrative friction for a quiet rural property and manageable long-term carry cost. Watch-outs: workable self-sufficiency basics (31″/yr rainfall) and elevated mid-century heat, water, rain, or wildfire exposure.

Do you need a building permit in Karnes County, Texas?

Karnes County does not require a county building permit for a home in unincorporated areas, and it has no county-wide zoning. Onsite septic is permitted by Karnes County (OSSF Authorized Agent under TCEQ). Owner-builders may act as their own contractor to build their home. These answers are quoted from official sources and independently re-checked. Rules change and cities within the county differ — always confirm with the county before you buy or build.

Can you live in an RV or tiny home on your land in Karnes County?

Living in an RV on your own land in Karnes County is allowed: Unincorporated Karnes County: no county rule sets this, because Texas law gives zoning power only to certain counties, and Karnes County has no zoning ordinance. The county legal census found no county zoning ordinance, citing co.karnes.tx.us. Septic, floodplain, subdivision and health rules still apply; cities and towns set their own rules inside their limits. Chapter 231 does not grant a general statewide county zoning power; authority is provided through geographically or subject-matter limited subchapters. A tiny home is allowed. Confirm with the county before relying on it.

How much does land cost in Karnes County, Texas?

Land in Karnes County runs about $2,951 per acre, based on the latest county data.

What is the water situation in Karnes County?

Karnes County gets about 31" of rain a year, with severe drought in roughly 23.5% of years.

How remote is Karnes County?

A representative private-land location has about 15,040 people within a 30-minute drive and 5,014,934 within two hours. The road-network catchments count population across county lines and clusters of smaller cities; straight-line radius values remain available as a comparison.

Off-grid gear

Going off-grid in Karnes County means bringing your own water and power. The kit we’d start with:

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How Karnes compares in Texas

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