Bolthole Index

St. Mary Parish, Louisiana

Building permits, zoning and land rules in St. Mary Parish, Louisiana

63Index Score / 100
#43 of 64 in Louisiana

St. Mary Parish, Louisiana requires building permits for regulated construction, and its Planning & Zoning Department directs applicants to MGO Connect.12 The parish also has zoning for unincorporated land, while individual sewerage systems need a state health permit before installation, alteration or operation.34

At a glance

Building permit
Required for regulated construction; applications are online12
Zoning
Yes on unincorporated parish land3
Septic permit
Required from the Louisiana state health officer54
RV living
Private-land occupancy rule not confirmed; ask Planning & Zoning3
Tiny home
District standards may control size, placement and use67
Owner-builder
Licensing exemption available for a qualifying personal residence8
Private well
Licensed driller and state registration required; domestic wells follow post-installation notice rules9

Who to call

Planning & zoning

St. Mary Parish Planning & Zoning Department

Parish permit applications and Planning & Zoning questions

(337) 828-4100 ext. 5280

[email protected]

Fifth Floor Courthouse, Franklin, LA 70538

Online permits →

Septic permits

St. Mary Parish Health Unit

Local Environmental Health contact for St. Mary Parish

985.380.2441

1200 David Drive, Morgan City, LA 70380

Contact details are copied from each office’s official page and were checked against it on September 29, 2026.

Do you need a building permit in St. Mary Parish, Louisiana?

Yes. St. Mary Parish reports building permits as required and directs planning and zoning permit applications through MGO Connect.12 Louisiana has adopted a State Uniform Construction Code, and residential-code enforcement covers new construction, reconstruction, additions to homes already built to the code and extensive alterations.10 For an existing dwelling, an alteration is extensive when all work areas exceed 50% of the dwelling-unit area.11 The parish page does not publish local fees, review times, inspection stages or approval criteria, so ask Planning & Zoning for the current project checklist before ordering plans.2

Who issues permits in St. Mary Parish, and how do you reach them?

Start with the St. Mary Parish Planning & Zoning Department for a parcel outside an incorporated municipality. The department is on the Fifth Floor of the Courthouse in Franklin, lists (337) 828-4100 ext. 5280 and [email protected], and directs applicants to MGO Connect.12 State law makes parish enforcement the local path for the statewide construction code in unincorporated areas, while a municipality may administer its own local process.13 The parish page confirms the planning and zoning application route but does not state its fee schedule, review time, required inspection sequence or certificate-of-occupancy procedure.2 Ask the department to identify the zoning district, permit type, submittal documents, fees and inspection contacts for the exact parcel before work begins.12

Does St. Mary Parish have zoning?

Yes. St. Mary Parish's Unified Development Code governs zoning, subdivision and development on unincorporated land.3 Louisiana law allows a parish to create zoning districts and regulate structure size, lot occupancy, open space, density, location and land use, but those standards can differ by district.14 Consequently, a parcel's setbacks, height, lot coverage and minimum dwelling size cannot be answered from a parishwide number; the applicable district controls.715166 We could not confirm the current district map or whether municipal rules replace parish zoning inside a particular town. Ask Planning & Zoning to verify jurisdiction and district from the parcel number before relying on a listing description.12

How do septic permits work in St. Mary Parish?

Louisiana, rather than the parish government, regulates individual sewerage systems: no one may install, alter or operate one without first obtaining a permit from the state health officer.54 State review includes the plans and considers whether connection to community sewer is feasible, along with soil, drainage, lot dimensions and health risks.4 Final approval requires compliance verification through an on-site state inspection, an installer certification or both, and the installer certification is due within 15 days after completion.17 The St. Mary Parish Health Unit in Morgan City lists Environmental Health service and can route local questions.18 USDA soil data rates 0% of parish soils as free of severe limitations for a conventional drain field; that rating makes an early site evaluation essential but does not by itself prove that a parcel cannot support an approved system.19

Can you live in an RV or tiny home on your land in St. Mary Parish?

We could not confirm a St. Mary Parish rule that allows or forbids long-term RV occupancy, temporary private-land camping or tiny-home occupancy. The parish has zoning on unincorporated land, and Louisiana's framework leaves dwelling size, setbacks and similar standards to local zoning districts.367 A tiny home therefore still needs a district and code review, while an RV question needs a direct parcel-specific answer from Planning & Zoning.12 State-park stay limits do not answer whether someone may occupy an RV on private land, because those limits apply only to facilities operated or reserved through the Louisiana Office of State Parks.20 Before buying, give Planning & Zoning the parcel number and describe whether the unit is temporary, connected to utilities or intended as a full-time dwelling.12

Building a home in St. Mary Parish: the steps, in order

  1. Ask St. Mary Parish Planning & Zoning to confirm jurisdiction, the parcel's zoning district and the applicable dimensional standards.312
  1. Confirm sewer availability; if an individual system is needed, start state health review before fixing the house location.214
  1. Submit the planning and zoning permit application through MGO Connect and ask for the current fee, plan and inspection checklist.212
  1. If building your own personal residence, claim the owner-builder licensing exemption by affidavit; it generally covers no more than one personal residence per year and does not waive permits or safety codes.8 A farmer building for agricultural purposes on owned or leased land may also have a contractor-licensing exemption, but it does not waive building, zoning, floodplain or septic requirements.22
  1. Obtain a signed, numbered LaDOTD access permit before constructing a connection to a state highway.23
  1. Complete required building inspections and obtain final septic verification before occupancy.2417

What should you check before buying land in St. Mary Parish?

Check septic feasibility first: 0% of mapped parish soils rate as free of severe limitations for a conventional drain field, so an inexpensive parcel may need a costlier approved system.19 Check flood status and elevation next; development in a regulatory floodway needs a no-rise certification before permitting under the statewide floodway standard, while the reviewed material does not identify the parish's local floodplain administrator.25 Verify legal road access and determine whether a driveway meets a parish road or a state highway, because state-highway connections require LaDOTD approval.23 If planning a well, Louisiana requires a licensed driller and state registration, with domestic wells following the applicable post-installation notification rule.9 Finally, price insurance for the parcel: the typical annual premium is about $3,051, while the effective property-tax rate is about 0.4% and the median annual bill is about $515.262728

Watch-outs

  • The parish page gives only a partial permit process and does not publish current fees, review times or inspection stages; request the project checklist from Planning & Zoning before budgeting.2
  • A state septic permit is required before installing, altering or operating an individual sewerage system, and parish soils commonly pose severe conventional-drain-field limitations.419
  • Private-land RV and tiny-home occupancy rules remain unconfirmed; ask Planning & Zoning for a written parcel-specific answer.12

Sources

  1. St. Mary Parish Planning & Zoning Department (2026 county census)
  2. Planning & Zoning Department - St. Mary Parish Government, quoted and re-checked
  3. St. Mary Parish Unified Development Code (2026 county census)
  4. Louisiana Administrative Code Title 51, Part XIII, Public Health—Sanitary Code (Louisiana statewide rule), quoted and re-checked
  5. Louisiana Administrative Code Title 51, Part XIII, Public Health—Sanitary Code (Louisiana statewide rule), quoted and re-checked
  6. RS 33:4721 — Regulation of size and use of buildings (Louisiana statewide rule), quoted and re-checked
  7. RS 33:4721 — Regulation of size and use of buildings (Louisiana statewide rule), quoted and re-checked
  8. Louisiana Revised Statutes § 37:2157 — Exemptions, quoted and re-checked
  9. Louisiana Administrative Code, Title 43, Part VI, §701 (Louisiana statewide rule), quoted and re-checked
  10. RS 40:1730.28 - Louisiana State Legislature, quoted and re-checked
  11. Louisiana Revised Statutes 40:1730.23 — Enforcement of building codes by municipalities and parishes (Louisiana statewide rule), quoted and re-checked
  12. St. Mary Parish Planning & Zoning Department (stmaryparishla.gov)
  13. RS 40:1730.23. Enforcement of building codes by municipalities and parishes (Louisiana statewide rule), quoted and re-checked
  14. RS 33:4780.40 — Regulation authorized (Louisiana statewide rule), quoted and re-checked
  15. RS 33:4721 — Regulation of size and use of buildings (Louisiana statewide rule), quoted and re-checked
  16. RS 33:4721 — Regulation of size and use of buildings (Louisiana statewide rule), quoted and re-checked
  17. Louisiana Administrative Code Title 51, Part XIII, Public Health—Sanitary Code (Louisiana statewide rule), quoted and re-checked
  18. St. Mary Parish Health Unit (ldh.la.gov)
  19. Share of soils without severe limits for a conventional septic drain field (USDA SSURGO): Bolthole Index county data
  20. Louisiana Office of State Parks Policy and Procedure Memorandum #6 — Reservation Changes and Refunds (Louisiana statewide rule), quoted and re-checked
  21. Louisiana Administrative Code Title 51, Part XIII, Public Health—Sanitary Code (Louisiana statewide rule), quoted and re-checked
  22. Louisiana Revised Statutes 37:2157, quoted and re-checked
  23. LaDOTD Access Connections Policy (Louisiana statewide rule), quoted and re-checked
  24. Louisiana Revised Statutes 40:1730.23 — Enforcement of building codes by municipalities and parishes (Louisiana statewide rule), quoted and re-checked
  25. State of Louisiana No Rise Certification Guidance (Louisiana statewide rule), quoted and re-checked
  26. Typical home insurance premium: Bolthole Index county data
  27. Effective property tax rate: Bolthole Index county data
  28. Median property tax bill: Bolthole Index county data

Written September 29, 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

St. Mary Parish in Louisiana

63
County map
St. Mary Parish highlighted among the Louisiana counties · colored by Index score

How St. Mary Parish scores

Seclusion67100% ev.
Self-Sufficiency46100% ev.
Admin Boringness48100% ev.
Durability54100% ev.
Property Autonomy44100% ev.
Carry Cost89100% ev.

Evidence strength: 100%. This reports direct-source completeness and fallback use; it is separate from the score and is not a confidence interval. How it works →

$116kTypical home
0.4%Property tax
$3,498Land / acre
60.7"Annual rain
8.9% of yrsSevere drought
1.2 / yr (+1.1)Mid-century 100°F days
16.2 daysMid-century dry spell
3.43" (+6.6%)Mid-century 1-day rain
1.23×Wildfire change factor
100%Forward climate coverage
$3,051Home insurance / yr
-0.3% / yrInsurance growth
6.62%Nonrenewal rate
county median (2+ published ZIPs)Insurance basis
1,205,858People within 2 hr
36,463Radius comparison (15 mi)
84.7People / sq mi
3.5%Federal land
100%Land at 15% slope or less
0%Septic soil without severe limits
0 acWorkable land screen
53.5%Wooded land
48 tonsBiomass / forest ac
69.2°FAvg temp

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Answers from the rulebook for St. Mary Parish

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

St. Mary Parish rules

  • Permit processPublished (with conditions)

    Permit application process administered through the St. Mary Parish Planning & Zoning Department.

    • The page directs applicants to complete permit applications through the MGO Connect portal.
    • The opened page does not state review times, fees, inspection stages, or approval criteria.
    “Complete Permit Applications at: http://www.mgoconnect.org”
    One more reviewed finding on this topic
    • Partial — Planning and zoning permit applications handled by St. Mary Parish.
      “St. Mary Parish Unified Development Code: http://online.encodeplus.com/regs/stmary-la/ Complete Permit Applications at: http://www.mgoconnect.org”
  • County-wide zoningPresent

    The parish adopted a Unified Development Code (2014) that applies to all unincorporated lands and governs zoning, subdivision and development.

    St. Mary Parish Unified Development Code ↗Scouted from the county site, not yet independently re-checked

Louisiana rules that apply here

  • Building permitRequired

    Construction subject to Louisiana’s State Uniform Construction Code, including mandatory residential-code-covered new construction, reconstruction, additions to homes previously built to the International Residential Code, and extensive alterations.

    • Municipalities and parishes administer permit issuance and may use certified third-party providers.
    • The cited residential-code enforcement mandate applies to new construction, reconstruction, additions to homes previously built to the International Residential Code, and extensive alterations.
    • Local permitting procedures and code enforcement remain administered by the applicable municipality or parish.

    extensive alteration threshold: > 50 percent of dwelling-unit area (The statute defines an extensive alteration as an alteration when the total area of all work areas exceeds fifty percent of the dwelling unit.)

    “Enforcement procedures by building code enforcement officers [...] shall include examination or review of plans, drawings, or specifications; [...] and the issuance, denial, or revocation of permits.”
    One more reviewed finding on this topic
    • Limited — Construction subject to Louisiana State Uniform Construction Code enforcement by Louisiana parishes and municipalities.
      “Enforcement procedures by building code enforcement officers or third-party providers acting in the capacity of a building code enforcement officer shall include examination or review of plans, drawings, or specifications; the conducting of inspections; and the issuance, denial, or revocation of permits.”
  • Owner-builder exemptionConditional

    Owners of property supervising or assuming charge of construction, alteration, repair, improvement, movement, demolition, erection, or maintenance of their personal residence in Louisiana under the contractor-licensing exemption in La. R.S. 37:2157(A)(13).

    • The residence must be the homeowner's personal residence and the homeowner may not build more than one residence per year.
    • The one-year period commences on the date the certificate of occupancy is issued.
    • An owner may build more than one single-family dwelling during a one-year period only when an additional residence results from a change in the owner's legal marital status or employment status requiring relocation to another employment location more than fifty miles from the owner's personal residence.
    • An affidavit of exemption on a form provided by the Louisiana State Licensing Board for Contractors must be provided to obtain the building permit.
    • The owner-builder affidavit states that the house must be maintained as the owner's primary residence after issuance of the certificate of occupancy or completion of construction.
    • The exemption does not exempt licensable subcontractors from applicable licensure requirements.
    • Local and state health and life-safety code requirements continue to apply.
    • The official sources do not state a fee for the exemption or affidavit.

    maximum residences: 1 residence per one-year period (Additional single-family dwelling allowed when a change in legal marital status or employment status requires relocation more than 50 miles from the owner's personal residence.) · relocation distance: > 50 miles (Applies to the employment-relocation exception.) · one-year period start: date of issuance of certificate of occupancy

    “Owners of property who [...] assume charge of the construction [...] of their personal residences, if the homeowner does not build more than one residence per year.”
    2 more reviewed findings on this topic
    • Available (with conditions) — A property owner in St. Mary Parish who supervises, directs, or assumes charge of construction of the owner's personal residence, subject to Louisiana's statutory conditions and the local permitting process.
      “Owners of property who supervise [...] their personal residences, if the homeowner does not build more than one residence per year.”
    • Available (with conditions) — Owner-supervised construction and related residential-contractor licensure exemptions that may apply in St. Mary Parish.
      “Owners of property who supervise, superintend, oversee, direct, or in any manner assume charge of the construction, alteration, repair, improvement, movement, demolition, putting up, tearing down, or maintenance of their personal residences, if the homeowner does not build more than one residence per year.”
  • Building code adoptedAdopted

    The Louisiana State Uniform Construction Code, including the International Residential Code, applies statewide to regulated construction, including new residential construction, reconstruction, additions to homes previously built to the International Residential Code, and extensive alterations.

    • The International Residential Code enforcement described by the statute is mandatory only for new construction, reconstruction, additions to homes previously built to the International Residential Code, and extensive alterations.
    • Appendix J, Existing Buildings and Structures, may be adopted and enforced only at the option of a parish, municipality, or regional planning commission.
    • The statute excludes Part I-Administration and VIII-Electrical from the International Residential Code adoption described in the excerpt.
    • The council's initial code became effective January 1, 2007.
    • The statute page identifies an amendment effective July 1, 2026.

    extensive alteration threshold: > >50 percent of dwelling-unit area (The statute defines an extensive alteration as one where the total area of all work areas exceeds fifty percent of the dwelling unit.) · initial code effective date: 2007-01-01 · listed amendment effective date: 2026-07-01

    “The applicable standards referenced in that code are included for regulation of construction within this state.”
    4 more reviewed findings on this topic
    • Adopted (with conditions) — Louisiana construction subject to the State Uniform Construction Code, including St. Mary Parish.
      “Except as provided in Subsection C of this Section, the council shall evaluate, adopt, and amend only the latest editions of the following as the State Uniform Construction Code:”
    • Adopted (with conditions) — Construction regulated by the Louisiana State Uniform Construction Code statewide.
      “The commission shall evaluate, adopt, and amend only the latest editions of all of the following as the Uniform Construction Code:”
    • Partial — The Louisiana State Uniform Construction Code's statewide adoption of the International Building Code and its referenced standards for construction in Louisiana.
      “(1) International Building Code, not including Parts I-Administrative, and Chapter 27-Electrical. The applicable standards referenced in that code are included for regulation of construction within this state. The appendices of that code may be adopted as needed, but the specific appendix or appendices shall be referenced by name or letter designation at the time of adoption.”
    • Adopted — The Louisiana State Uniform Construction Code, including the International Residential Code, regulates construction statewide and applies to new residential construction, reconstruction, additions to homes previously built to the code, and extensive alterations.
      “The International Residential Code, not including Part I-Administration and VIII-Electrical. The applicable standards referenced in that code are included for regulation of construction within this state. The enforcement of such standards shall be mandatory only with respect to new construction, reconstruction, additions to homes previously built to the International Residential Code, and extensive alterations; however, a municipality, parish, or regional planning commission may enforce Appendix J of the code at its option.”
  • InspectionsRequired

    Commercial and residential structures subject to Louisiana State Uniform Construction Code enforcement.

    • Inspections are conducted by a building code enforcement officer or certified third-party provider.
    • Except for roofing inspections, the inspector or provider must be present on site.
    • A certified third-party provider may accept location-verified geotagged photographs or videos for required roofing and reroofing inspections.
    • The parish, municipality, regional planning commission, or third-party provider administering the inspection may prescribe lawful fees.
    “For purposes of code enforcement pursuant to this Section, a building code enforcement officer or a certified third-party provider shall conduct all inspections of any commercial or residential structure and for all inspections, other than roofing inspections, shall be present on site for such inspections.”
    One more reviewed finding on this topic
  • Certificate of occupancyLimited

    New residential construction in a parish or municipality enforcing the Louisiana State Uniform Construction Code, particularly where a residential mortgage lender is involved.

    • The statute expressly addresses a certificate of occupancy issued by a local building official or third-party provider for new residential construction.
    • Upon receipt of that certificate, a lender providing a residential mortgage loan must file a copy in the parish conveyance records.
    • The homeowner must provide the lender a copy.
    • The lender may assess only a reasonable filing charge not exceeding the amount charged by the parish for filing the document.
    • If the construction-code provisions cease to be enforced in a parish, the statutory filing provisions become null and void there.
    • In areas where windblown-debris storm shutters are required, occupancy may be allowed upon an affidavit that the owner ordered the shutters; installation must occur within ninety days, followed by notification and final inspection.

    storm-shutter installation deadline: 90 days (Applies when occupancy is allowed under the storm-shutter affidavit provision.)

    “Upon receipt of the certificate of occupancy issued by a local building official or third-party provider for a new residential construction, a lender who provides a residential mortgage loan for the purchase of such new residential construction shall file a copy of the certificate of occupancy in the conveyance records of the parish where the new residential construction is located.”
    One more reviewed finding on this topic
  • Zoning districtsPartial

    Louisiana's statutory zoning framework: parish governing authorities may create zoning districts, while local authority over land-use and zoning requirements is reserved to parishes or municipalities.

    • The statute does not publish a statewide map or a complete list of actual district boundaries.
    • District regulations must be uniform for each class or kind of land and structure within a district, but may differ between districts.
    • Actual zoning districts and ordinances must be obtained from the applicable parish or municipality.
    “the governing authority of a parish may divide the parish into districts of such number, shape, and area as may be deemed best suited”
  • Minimum dwelling sizeDistrict specific (with conditions)

    Municipal zoning districts in Louisiana; the state authorizes municipalities to regulate the size of structures, which may include dwelling-size standards, but does not establish one statewide minimum dwelling size in this provision.

    • Any actual minimum dwelling-size requirement must be found in the applicable municipality's zoning ordinance or district regulations.
    • Local zoning ordinances remain subject to the judicial-review standards stated in the statute.
    “size of structures”
  • Minimum lot sizeSpecified

    Certain subdivisions outside incorporated areas consisting of single-family lots owned by one owner or co-owners, subject to the parish and population exclusions in R.S. 33:106.1(A).

    • Minimum lot area is 22,500 square feet.
    • Minimum frontage is 125 feet.
    • For nonrectangular lots with less than 125 feet frontage, average width must be 125 feet and frontage must be at least 60 feet.
    • Lots must support sewage-disposal systems and individual water systems meeting Louisiana Department of Health suitability requirements.
    • The statutory planning-commission exemption does not apply in the parishes listed in R.S. 33:106.1(A), municipalities within those parishes, or jurisdictions with a population greater than 300,000.
    • The exemption preserves planning-commission authority over utilities, drainage, sewerage disposal, and street-planning dimensions, composition, and alignment.

    minimum lot area: >= 22500 square feet · minimum frontage: >= 125 feet (Nonrectangular lots may have less than 125 feet frontage only if average width is 125 feet and frontage is at least 60 feet.)

    “minimum square footage of twenty-two thousand five hundred square feet, with a minimum width of one hundred twenty-five feet of frontage”
  • SetbacksDistrict specific (with conditions)

    Municipal zoning districts in Louisiana; municipalities may regulate the size of yards, courts, and other open spaces, which can include setbacks.

    • The applicable setback is determined by the local zoning ordinance and district.
    • No statewide numerical setback is established by the cited statute.
    “size of yards, courts, and other open spaces”
  • Lot coverageDistrict specific (with conditions)

    Municipal zoning districts in Louisiana; municipalities may regulate the percentage of a lot that may be occupied.

    • The applicable lot-coverage percentage is determined by the local zoning ordinance and district.
    • No statewide numerical lot-coverage limit is established by the cited statute.
    “percentage of lot that may be occupied”
  • Building heightDistrict specific (with conditions)

    Municipal zoning districts in Louisiana; municipalities may regulate building height and number of stories.

    • The applicable height limit is determined by the local zoning ordinance and district.
    • No statewide numerical building-height limit is established by the cited statute.
    “height, number of stories”
  • Who permits septicState

    Statewide regulation of individual sewerage systems in Louisiana.

    • The Louisiana sanitary code assigns permitting and approval decisions to the state health officer.
    • The rule is promulgated under R.S. 40:4(A)(6) and R.S. 40:5(9)(20).
    “A person shall not install, cause to be installed, alter subsequent to installation, or operate an individual sewerage system of any kind without first having obtained a permit from the state health officer.”
  • Septic permitRequired

    Installation, alteration, or operation of any individual sewerage system in Louisiana, including septic tank systems.

    • A permit from the state health officer is required before installation, alteration, or operation.
    • Plans and specifications must be approved as part of the permit.
    • A temporary installation permit may issue only after the state health officer determines connection to a community-type sewerage system is not feasible and the soil, drainage, lot size/dimensions, and related factors are unlikely to create a nuisance or public health hazard.
    • Permits for lots in formal subdivisions require an official recorded plat/property survey filed with and approved by the Office of Public Health for individual sewerage use.

    permit stages: two-stage process

    “A person shall not install, cause to be installed, alter subsequent to installation, or operate an individual sewerage system of any kind without first having obtained a permit from the state health officer.”
  • Septic inspectionLimited

    Final approval of individual sewerage system installations in Louisiana.

    • Final approval requires verification that the system was installed in compliance with the code.
    • Verification may be by an on-site inspection by a representative of the state health officer and/or a completed Certification by Installer from the licensed installer.
    • The installer must notify the appropriate local Parish Health Unit before installation.
    • The certification must be submitted within 15 days after completion.

    certification submission deadline: 15 days after completion

    “A final permit approving the installation, shall be issued only upon verification that the individual sewerage system has been installed in compliance with this code. The verification of such installation shall be determined by means of an on-site inspection conducted by a representative of the state health officer and/or in the form of a completed "Certification by Installer" form submitted to the state health officer by the licensed installer.”
  • Off-grid sanitationLimited

    Use of individual or alternative onsite sewage systems instead of a community-type sewerage system in Louisiana.

    • Individual sanitation is allowed only when community-type sewerage is unavailable or connection is not feasible.
    • The system requires state-health-officer permitting and approved plans.
    • A conventional septic tank system may be used where community sewer is unavailable; an individual mechanical plant may be used only where community sewer is unavailable and the state health officer determines a conventional system would not function properly.
    • Innovative systems are limited to no more than three experimental or developmental installations statewide and require specifically approved plans, specifications, testing procedures, and a prior permit.

    experimental/developmental installations: <= 3 statewide maximum

    “The total number of such installations shall not exceed three throughout the state and shall be approved under the following conditions.”
  • Well permitLimited

    New water wells statewide in Louisiana, including wells outside critical groundwater areas, except the types specifically subject to post-installation notification or other exemptions.

    • All new water wells must be installed by a licensed water-well drilling contractor and registered through the Department of Transportation and Development within 30 days after completion.
    • Unless specifically listed in the exemptions, the owner must submit a water well notification form to the commissioner at least 60 days before installation.
    • Before construction begins, the drilling contractor must confirm that the Office of Conservation has received and responded to the installation notification.
    • Domestic wells, replacement wells, drilling rig supply wells, drought relief wells, and other wells exempted for just cause are subject to post-installation notification rules rather than the ordinary 60-day prior notification.
    • The commissioner reviews prior notifications within 30 days and may impose restrictions, request further information, or take no action; an additional 30-day review period may apply if further information is requested.
    • For large-volume wells or wells in a critical area of groundwater concern, the commissioner may fix allowable production, spacing, and metering; for other wells outside a critical area, an order may only fix spacing.
    • After written confirmation that no restrictions or further information are required, or when the owner accepts imposed restrictions, the owner need not wait the full 60 days and may begin drilling consistently with the notification and restrictions.

    prior notification period: 60 days (Does not apply to well types listed in LAC 43:VI §701.C and D.) · registration deadline after completion: 30 days (The applicable state registration requirement applies to all new water wells.) · additional review period if information requested: 30 days (Additional period begins when the requested information is received.)

    “require a water well notification form be submitted to the commissioner by the owner of the well at least 60 days prior to installation.”
  • Mandatory utility hookupSewer (with conditions)

    Residential or other individual sewerage-system sites governed by Louisiana Title 51 Part XIII.

    • A temporary individual-system permit may not issue until connection to a community-type sewerage system is determined not feasible.
    • A septic tank system may be used only where a community-type sewerage system is not available and the applicable code requirements are met.
    “Where a community-type sewerage system is not available, a septic tank system may be used provided that the requirements of §§511.B, 701, 703.A, and 705 are complied with.”
  • Agricultural exemptionConditional

    Agricultural-purpose subdivision regulation by parish planning commissions in Louisiana.

    • The statutory exclusion applies to parish planning regulations governing subdivision of land in unincorporated territory for purposes other than agricultural.
    • Municipal planning commissions are separately authorized to regulate subdivision within their jurisdictions; this claim does not establish a municipal agricultural exemption.
    • Other statutory rules may still apply, including utility, drainage, sewerage-disposal, and street-planning requirements for qualifying subdivisions under R.S. 33:106.1.
    “Before exercising the powers referred to in R.S. 33:110, a parish planning commission shall adopt regulations governing the subdivision of land within unincorporated territory within its jurisdiction for purposes other than agricultural.”
    One more reviewed finding on this topic
    • Available (with conditions) — Louisiana residential-contractor licensure exemption for a farmer doing construction for agricultural purposes on leased or owned land.
      “(4) Any farmer doing construction for agricultural purposes on leased or owned land.”
  • Subdividing landRegulated (with conditions)

    Subdivision regulation under Louisiana's statutory framework, administered through parish and municipal planning commissions.

    • A parish planning commission must adopt subdivision regulations before exercising its statutory powers; parish regulations apply to subdivision of land in unincorporated territory for purposes other than agricultural.
    • A municipal planning commission must adopt regulations before exercising its statutory powers, and municipal regulations apply within the municipality.
    • A planning commission generally must approve or disapprove a plat within 60 days, unless the applicant waives the requirement and consents to an extension.
    • The statutory framework allows local regulations concerning street arrangement, lot dimensions, utilities, drainage-related utility and sewerage requirements, improvements, and bonds or surety.
    • R.S. 33:106.1 limits planning-commission jurisdiction over specified qualifying subdivisions, while preserving requirements for utilities, drainage including sewerage disposal, and street planning dimensions, composition, and alignment.

    plat decision period: 60 days (Applicant may waive the requirement and consent to an extension.) · hearing notice: >= 5 days (Notice by certified mail and publication requirements apply; certain public-hearing waivers may be authorized by official subdivision regulations.)

    “Before exercising the powers referred to in R.S. 33:110, a parish planning commission shall adopt regulations governing the subdivision of land within unincorporated territory within its jurisdiction for purposes other than agricultural. Before exercising the powers referred to in R.S. 33:110 a municipal planning commission shall adopt regulations governing the subdivision of land within its jurisdiction.”
  • Driveway accessRequired

    Access connections or driveways connecting property to a Louisiana state highway and involving work in LaDOTD right-of-way.

    • The requirement applies to state-highway access connections; access to non-state local roads may instead be governed by the local government.
    • The permit certificate must be signed and numbered before construction begins.
    • Additional design, drainage, traffic-study, inspection, bonding, and restoration conditions may apply.
    “Only upon possession of a signed and numbered Access Connection Permit Certificate may the applicant begin construction of an access connection.”
  • Building in a floodplainLimited

    Proposed development in a regulatory floodway in Louisiana communities using the State of Louisiana no-rise certification guidance.

    • A no-rise certification with supporting technical data may be submitted when modeling shows 0.00 feet rise.
    • If the project causes a rise, it must be modified, compensated for, or proceed through a floodway revision.
    • Floodway revision requests must come from the community and be obtained before permit issuance and development.
    • The community official must review and approve the supporting data and engineering certification before issuing a permit.

    permitted modeled rise for no-rise certification: 0 feet

    “Requests for floodway revisions must come from the community and be obtained prior to the issuance of a permit and proceeding with the development.”
  • Permit feesPublished (with conditions)

    State Fire Marshal plan-review or document fees for projects whose plans and specifications are submitted to the Louisiana Office of State Fire Marshal, Code Enforcement and Building Safety.

    • A $5 postage and handling fee applies in addition to the plan-review or document fee.
    • Fees vary by occupancy classification, project area, number of sprinkler heads or other devices, appeal type, and review type.
    • The statute provides a first-submission exemption from all other charges for state and local political subdivisions; subsequent submissions require the fees.
    • Performance-based reviews cost twice the applicable review fee plus an additional $100, with a stated $50 resubmission amount for smoke-control and timed-egress reviews.

    postage and handling fee: 5 USD (Does not apply to exemption requests and facsimile transmissions.) · assembly occupancy plan review fee for area 0-2500 square feet: 30 USD · educational occupancy plan review fee for area 0-5000 square feet: 30 USD · hotels, dormitories, apartments, lodgings, rooming houses, and residential or board care facilities plan review fee for area 0-2500 square feet: 30 USD · mercantile/business plan review fee for area 0-3000 square feet: 30 USD · industrial, storage, and special structures plan review fee for area 0-10000 square feet: 30 USD

    “In addition to a postage and handling fee of five dollars, the owner of the project who submits the plans and specifications shall pay to the office of state fire marshal, code enforcement and building safety a plan review or document fee based on the following schedule:”
  • Campground & park staysProhibited

    Overnight camping on Louisiana public property that is not a designated campground.

    • The prohibition applies to public property owned or controlled by the state or any local or political subdivision.
    • Designated campgrounds are excluded from the prohibition.
    • Violation may result in a fine of not more than $500, imprisonment for not more than six months, or both.
    • The statute states an effective date of June 9, 2026.

    maximum fine: <= 500 USD · maximum imprisonment: <= 6 months

    “Unauthorized camping on public property is the intentional use of any tent [...] to permit overnight use on public property that is not a designated campground.”
    One more reviewed finding on this topic
  • county zoning authorityLimited

    Louisiana parish governing authorities' zoning authority over parish land, including unincorporated areas, under the statewide parish zoning enabling subpart.

    • The general parish zoning authorization excludes Rapides, Jefferson, Sabine, and Webster Parishes.
    • A parish may divide the parish into zoning districts, and regulations may differ between districts but must be uniform for each class or kind of land and structure within each district.
    • Zoning regulations must comply with the required comprehensive plan.
    • No regulation becomes effective until after a public hearing.
    • Notice must be published once a week in three different weeks in the official parish journal, with at least fifteen days between first publication and hearing.
    • At least ten days before the hearing, the parish must make a good-faith attempt to notify owners of record by certified mail; when more than ten parcels are zoned or rezoned, official-journal advertisement is adequate notice.
    • To use the powers of the subpart, the parish governing authority must appoint a zoning commission, which must hold a public hearing and issue its final report before the governing authority holds its public hearings or acts.

    excluded parishes: Rapides, Jefferson, Sabine, and Webster · publication interval: 3 different weeks · minimum elapsed time before hearing: >= 15 days · owner notice deadline: >= 10 days before hearing (Good-faith certified-mail notice; official-journal advertisement is adequate when more than ten parcels are zoned or rezoned.)

    “For the purpose of promoting the health, safety, morals, or general welfare of the community, the governing authorities of parishes, other than the parishes of Rapides, Jefferson, Sabine, and Webster, or their duly created boards of adjustment are hereby authorized to regulate and restrict the height, number of stories, and size of structures; the percentage of lots that may be occupied; courts and other open spaces; the density of population; and the location and use of the buildings, structures, and land for trade, industry, residence, or other purposes.”
    One more reviewed finding on this topic
    • Limited — Louisiana parish governing authorities adopting zoning regulations affecting parish territory, including unincorporated areas.
      “the governing authorities of parishes, other than the parishes of Rapides, Jefferson, Sabine, and Webster, or their duly created boards of adjustment are hereby authorized”
  • county building authorityGeneral

    Louisiana parishes may enforce the statewide construction codes and administer building-code enforcement, including permits and inspections, in unincorporated areas.

    • Parishes must enforce only the construction codes provided in the Louisiana State Uniform Construction Code Part.
    • Enforcement includes plan review, inspections, and issuance, denial, or revocation of permits.
    • Each parish must appoint a council-certified building official or contract for those services so the unincorporated area is under the jurisdiction of a certified building official.
    • A parish may use a certified building inspector instead of a certified building official for no more than four years from the date the state uniform construction code becomes effective in the parish.
    • The statute preserves federal manufactured-housing requirements and Louisiana Manufactured Housing Commission jurisdiction for manufactured-home construction, installation, service, renovation, repair, and warranty work.
    • The statute page identifies an amendment effective July 1, 2026.

    temporary certified-inspector period: <= 4 years (Measured from the date the state uniform construction code becomes effective in the parish or municipality.)

    “all municipalities and parishes in this state shall enforce only the construction codes provided for in this Part.”
    One more reviewed finding on this topic
    • General — Louisiana parishes' authority and duty to enforce the state construction codes, including residential construction codes, through building-code enforcement officers or certified third-party providers.
      “Notwithstanding any other law to the contrary relating to the authority of local governments to enforce construction codes, all municipalities and parishes in this state shall enforce only the construction codes provided for in this Part. All municipalities and parishes shall use building code enforcement officers or certified third-party providers contracted by the municipality, parish, or regional planning commission to act in the capacity of a building code enforcement officer to enforce the provisions of this Part.”

Still unanswered

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

  • Local zoning — Local zoning within St. Mary Parish, including incorporated municipalities and unincorporated areas.
  • Living in an RV — Long-term RV occupancy on private land in St. Mary Parish.
  • Camping on your land — Temporary camping on private land in St. Mary Parish.
  • Tiny homes — Tiny-home occupancy in St. Mary Parish.
  • Manufactured homes — Manufactured-home occupancy in St. Mary Parish.
2 more unanswered
  • Accessory dwellings
  • Short-term rentals

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 St. Mary Parish, Louisiana

Is St. Mary Parish a good place to live off-grid or homestead?

St. Mary Parish scores 63/100 on the Bolthole Index, a solid county profile. Its strengths: manageable long-term carry cost and about 36,463 people within 15 miles.

Do you need a building permit in St. Mary Parish, Louisiana?

St. Mary Parish generally requires a residential building permit, and it enforces county zoning. Onsite septic is permitted by Louisiana Department of Health, Office of Public Health (St. Mary Parish Health Unit). 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.

How much does land cost in St. Mary Parish, Louisiana?

Land in St. Mary Parish runs about $3,498 per acre, based on the latest county data.

What is the water situation in St. Mary Parish?

St. Mary Parish gets about 60.7" of rain a year, with severe drought in roughly 8.9% of years.

How remote is St. Mary Parish?

A typical private-land location has about 36,463 people within 15 miles and 3,156,216 within 100 miles. These radius catchments are the published fallback where road routing is unavailable.

Off-grid gear

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

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How St. Mary compares in Louisiana

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