Bolthole Index

Fremont County, Wyoming

Building permits, zoning and septic rules in the Town of Hudson, Wyoming

The Town of Hudson, Wyoming does not require a building permit, but residents must notify the town of their plans and stop by to discuss them1. Mobile and modular homes outside a mobile-home park need a town permit and a certificate of occupancy2. We could not confirm whether Hudson has its own zoning. Septic permits are required and the Fremont County Planning Department handles small systems countywide3.

At a glance

Building permit
Not required in Hudson, but you must notify the town and discuss your plans1
Mobile or modular home
Town permit before setup, plus a certificate of occupancy after inspection (outside a mobile-home park)42
RV living
Up to 30 days for visitors; longer needs a town permit, limited to six months and renewable by Town Council56
Zoning
Town zoning not confirmed (ask Hudson Town Hall); Fremont County has no county-wide zoning7
Septic
Permit required; Fremont County Planning handles small residential systems89
Wells
State Engineer permit required before drilling10

Who to call

Building permits

Town of Hudson (Town Hall)

Notice of building plans, mobile-home and RV permits, and the Town Clerk/Treasurer's certificates of occupancy inside Hudson

(307) 332-3605

333 South Main Street

Septic permits

Fremont County Planning Department (Small Wastewater)

Small wastewater (septic) permits and inspections for Fremont County

(307) 332-1077

450 North 2nd Street, Room 360, Lander, Wyoming 82520

Contact details are copied from each office’s official page and were checked against it on October 15, 2026.

Off-grid gear

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

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Do you need a building permit in Hudson, Wyoming?

No. The Town of Hudson states: "While you do not need a building permit in Hudson, you do need to notify the town of your plans. Please stop by to discuss."11 The town's rule for building plans inside Hudson town limits is that residents notify the town and talk it over1.

That is different from having no rules. A mobile or modular home placed outside a mobile-home park needs a permit from the Town Clerk/Treasurer, and the applicant pays a fee that Town Council sets from time to time12. We could not find a Hudson section adopting a residential building code, so ask Town Hall whether any code standard applies to a site-built home11.

Who handles building permits and inspections in Hudson?

Hudson Town Hall is the first call for anything built inside town limits11. The Town Clerk/Treasurer issues permits for mobile and modular homes, and applicants supply the written information the Clerk/Treasurer asks for about applicable codes or standards13.

For a mobile or modular home outside a mobile-home park, the public works official inspects utility connections, tie-down provisions and skirting before a certificate of occupancy can be issued14. Fremont County does not issue certificates of occupancy15, so the town's certificate is the one that matters inside Hudson. Fremont County has no county-specific building codes of its own16.

Does Hudson have zoning, and what does it mean for RVs and mobile homes?

We could not confirm that Hudson has a zoning ordinance, a zoning map or zoning districts; the town's land-use code we reviewed covers mobile homes and trailers but no district schedule. Ask Town Hall before you assume lot size, setback or height limits either way11.

On mobile homes, Hudson's code says they are allowed anywhere within the corporate town limits, provided other applicable building lot standards are met4.

Fremont County has no county-wide zoning, but its floodplain zoning regulations cover FEMA flood hazard zones around Lander, Riverton, Dubois and Hudson7. The county's separate floodplain page says its regulations exclude areas within city limits17, so confirm with the Planning Department which rule applies to a given lot18.

Can you live in an RV on your land in Hudson?

Yes, for a limited time. Temporary or visitor occupancy of an RV camper inside Hudson is allowed for up to 30 days5. Living in the RV beyond that requires the real-property owner to apply to the town for a permit5.

Occupancy of an RV camper for living quarters is prohibited without a town permit, and a permit is limited to a six-month term; Town Council can approve renewals through subsequent applications6. If you plan to camp on a lot while you build, apply early and plan for renewal. We could not find a Hudson rule on tiny homes, so ask Town Hall how a tiny home would be treated11.

How do septic permits work inside Hudson?

A permit to construct is required to install any component of a small wastewater system under Wyoming's water quality rules8. Fremont County says it requires a permit for all small wastewater (septic) systems that generate less than 2,000 gallons per day3, and that residential systems below that size are permitted through the Fremont County Small Wastewater Regulations9.

The county's septic inspection happens before backfilling, by a representative of the Planning Department19. Wyoming DEQ handles residential wastewater above 2,000 gallons per day and high-strength commercial systems20. We could not find a Hudson-specific septic rule or confirm whether a given lot is served by town sewer, so call the Planning Department and Town Hall before you buy18.

Building a home in Hudson: the steps, in order

  1. Visit or call Hudson Town Hall, notify the town of your plans and ask about zoning and any building standards1.
  2. If the home is a mobile or modular unit outside a mobile-home park, get the Town Clerk/Treasurer's permit before setup and pay the fee412.
  3. Apply for a State Engineer permit before drilling a well10.
  4. Apply to the Fremont County Planning Department for a small wastewater permit, and schedule the inspection before backfilling319.
  5. For a mobile or modular home, pass the public works inspection and get a certificate of occupancy before anyone moves in2.

What stays with Fremont County, and what to check before you buy in Hudson

Septic permits and inspections come from the Fremont County Planning Department in Lander18, and well permits come from the Wyoming State Engineer10. For land outside town limits, see the Fremont County page.

County-level numbers give context: Fremont County's effective property tax rate is about 0.6%21, and USDA rates about 29% of its soils as not limited for a conventional septic drain field, so many lots need a site evaluation or an engineered system22.

Watch-outs

  • We could not confirm whether Hudson has zoning, setbacks or lot-size rules, so call Hudson Town Hall before you buy11.
  • An RV is limited to 30 days of visitor occupancy, and a town permit for living in it lasts six months at a time56.
  • Fremont County lists Hudson among the FEMA flood hazard areas covered by its floodplain zoning, so check a lot's flood status with the Planning Department7.

Sources

  1. FAQ and Concerns – Town of Hudson (Town of Hudson), quoted and re-checked
  2. Hudson Code § 151.48, Occupancy (Town of Hudson), quoted and re-checked
  3. Building Codes and Construction Recommendations, quoted and re-checked
  4. Hudson Code § 151.46, Placement of Mobile Homes, Modular Homes (Town of Hudson), quoted and re-checked
  5. Hudson Code § 151.48, Occupancy (Town of Hudson), quoted and re-checked
  6. Hudson Code § 151.48, Occupancy (Town of Hudson), quoted and re-checked
  7. Building Codes and Construction Recommendations, quoted and re-checked
  8. Wyoming Water Quality Rules, Chapter 25: Septic Tanks, Soil Absorption Systems, and Other Small Wastewater Systems (Town of Hudson), quoted and re-checked
  9. fremontcountywy.gov, quoted and re-checked
  10. Wyoming State Engineer's Office, Ground Water Frequently Asked Questions (Town of Hudson), quoted and re-checked
  11. Town of Hudson (Town Hall) (hudsonwy.org)
  12. Hudson Code § 151.47, Mobile Home, Modular Home Permits (Town of Hudson), quoted and re-checked
  13. Hudson Code § 151.47, Mobile Home, Modular Home Permits (Town of Hudson), quoted and re-checked
  14. Hudson Code § 151.48, Occupancy (Town of Hudson), quoted and re-checked
  15. Building Codes and Construction Recommendations, quoted and re-checked
  16. Building Codes and Construction Recommendations, quoted and re-checked
  17. Fremont County Floodplain Development Permit Application Information and Submittal Requirements, quoted and re-checked
  18. Fremont County Planning Department (Small Wastewater) (fremontcountywy.gov)
  19. Small Wastewater (Septic System) Application, quoted and re-checked
  20. fremontcountywy.gov, quoted and re-checked
  21. Effective property tax rate: Bolthole Index county data
  22. Share of soils USDA rates "not limited" for a conventional septic drain field (SSURGO). A strict rating: the median county is about 6% and a tenth of counties are 0%, so a low figure means most lots need a site evaluation or an engineered system, not that septic is impossible. Cite it only with that caveat: Bolthole Index county data

Written October 15, 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.

Answers from the rulebook for Town of Hudson

Town of Hudson’s own rules

  • Building permitNot required

    Building plans inside Hudson town limits.

    • The resident must notify the town of the plans and stop by to discuss them.
    “While you do not need a building permit in Hudson, you do need to notify the town of your plans. Please stop by to discuss.”
  • InspectionsLimited

    Mobile homes and modular homes located outside a mobile-home park inside Hudson town limits.

    • Inspection is required before issuance of the certificate of occupancy.
    • Inspection concerns utility connections, tie-down provisions, skirting, and other pertinent town requirements.
    “A certificate of occupancy shall be issued only after the mobile home or modular home has been inspected by the public works official for compliance with town requirements for utility connections, tie down provisions, skirting, and any other provisions pertinent thereto.”
  • Certificate of occupancyRequired

    Occupancy of a mobile home or modular home outside a mobile-home park inside Hudson town limits.

    • The Town Clerk/Treasurer must issue the certificate.
    • The unit must first be inspected by the public works official for town utility-connection, tie-down, skirting, and other pertinent requirements.
    “Occupancy of a mobile home or modular home outside of a mobile home park shall not be permitted until the Town Clerk/Treasurer has issued a certificate of occupancy.”
  • Living in an RVLimited

    RV-camper occupancy for living quarters inside Hudson town limits.

    • A real-property owner must obtain a town permit.
    • The permit term is limited to six months.
    • A permit may be renewed by subsequent applications approved by Town Council.

    RV-camper permit term: 6 months (May be renewable by subsequent applications approved by Town Council.)

    “Occupancy of an RV camper for living quarters is prohibited without the real property owner obtaining a permit from the town. Permits will be limited to a six month term of occupancy and the permit may be renewable by subsequent applications approved by Town Council.”
  • Camping on your landLimited

    Temporary or visitor occupancy of an RV camper inside Hudson town limits.

    • The allowed temporary/visitor term is up to 30 days.
    • For living occupancy beyond 30 days, the real-property owner must apply to the town for a continued-occupancy permit.

    temporary RV-camper occupancy: <= 30 days (Beyond 30 days requires an application to the town for continued RV-camper occupancy.)

    “Temporary/visitor occupancy of an RV camper will be allowed for a limited term of up to 30 days. If the living occupancy extends beyond a 30 day period, the real property owner must apply to the town for a permit to allow the continued occupancy of the RV camper.”
  • Manufactured homesAllowed (with conditions)

    Mobile-home occupancy inside Hudson town limits.

    • Other applicable building-lot standards must be met.
    • A mobile home outside a mobile-home park requires a Town Clerk/Treasurer permit before setup, location, replacement, or occupancy.
    • Outside a mobile-home park, occupancy also requires a certificate of occupancy after public-works inspection.
    “Mobile homes are allowed anywhere within the corporate town limits of the town, provided other applicable building lot standards are met.”
  • Permit feesVariable (with conditions)

    Town permits for mobile homes or modular homes outside mobile-home parks inside Hudson town limits.

    • The applicant must pay the fee set from time to time by Town Council.
    “Any applicant for a permit shall provide the Town Clerk/Treasurer with any written information that the Clerk/Treasurer may require with respect to any applicable codes or standards and shall pay a fee for the permit as shall be set from time to time by the Town Council.”
  • Permit processPartial

    Town permit process for mobile homes or modular homes outside mobile-home parks inside Hudson town limits.

    • Applicant supplies written information required by the Town Clerk/Treasurer concerning applicable codes or standards.
    • Applicant pays the Town Council-set permit fee.
    • The permit is issued by the Town Clerk/Treasurer as directed by Town Council.
    “Any applicant for a permit shall provide the Town Clerk/Treasurer with any written information that the Clerk/Treasurer may require with respect to any applicable codes or standards and shall pay a fee for the permit as shall be set from time to time by the Town Council. The permit shall be issued by the Town Clerk/Treasurer as directed by the Town Council.”

Rules another office applies inside Town of Hudson

Town of Hudson does not set these itself; the county, a health district or the state does, and they apply to every address inside its limits.

  • Septic permitRequired

    Installation of components of a small wastewater system inside Hudson town limits.

    • Permits may be general permits, permits by rule, or individual permits to construct under the cited state rules.
    • New construction or modification following the regulation's effective date must obtain authorization under a new permit.
    “The installation of all components of a small wastewater system require a permit to construct.”
  • Off-grid sanitationLimited

    Small onsite wastewater systems used for off-grid sanitation inside Hudson town limits.

    • Installation of all system components requires a permit to construct.
    • Permits may be general permits, permits by rule, or individual permits to construct.
    “The installation of all components of a small wastewater system require a permit to construct. Permits to construct are specified throughout this chapter as general permits, described in Chapter 3, Section 7; permit by rule, described in Chapter 3, Section 8; or as individual permits to construct, described in Chapter 3, Section 6.”
  • Well permitRequired

    A new well intended for beneficial use inside Hudson town limits.

    • An application for a permit to appropriate groundwater must be filed with the State Engineer before construction or related work.
    • Construction or work cannot proceed until the State Engineer grants the permit.
    “Any person who intends to acquire the right to beneficial use of any underground water in the state of Wyoming, shall, before commencing construction of any well or other means of obtaining underground water or performing any work in connection with construction or proposed appropriation of underground water or any manner utilizing the water for beneficial purposes, shall file with the State Engineer an application for a permit to make the appropriation (i.e., an Application for Permit to Appropriate Ground Water, or a U.W. 5 Form) and shall not proceed with any construction or work until a permit is granted by the State Engineer (W.S. 41-3-930).”

Still unanswered

We looked and could not find an official answer yet. Silence is not permission; ask Town of Hudson or Fremont County directly.

  • Owner-builder exemption — Owner-built dwellings inside Hudson town limits.
  • Building code adopted — Construction inside Hudson town limits.
  • Local zoning — Land inside Hudson town limits.
  • Zoning districts — Zoning districts inside Hudson town limits.
  • Minimum dwelling size — Dwellings inside Hudson town limits.
13 more unanswered
  • Minimum lot size
  • Setbacks
  • Lot coverage
  • Building height
  • Tiny homes
  • Accessory dwellings
  • Septic inspection
  • Mandatory utility hookup
  • Agricultural exemption
  • Subdividing land
  • Driveway access
  • Building in a floodplain
  • 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.

Unanswered questions are usually a sign that Town of Hudson publishes no rule on the point, not that none exists. Fremont County’s page lists the county offices to call.

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