Bolthole Index

Multnomah County, Oregon

Building permits, zoning and septic rules in Multnomah County, Oregon

38Index Score / 100
#34 of 36 in Oregon

A home in unincorporated Multnomah County, Oregon requires a building permit; cities issue building permits, with Portland Permitting & Development serving some unincorporated areas12. County Land Use Planning administers zoning in most unincorporated areas, while neighboring cities administer zoning in some pockets under agreements3. Portland Permitting & Development handles septic permits throughout Multnomah County, including inside cities4.

At a glance

Building permit
Required; issued by Portland Permitting & Development for some unincorporated areas, not by the county itself12
Zoning
Yes, administered by county Land Use Planning for most unincorporated areas; some pockets use city zoning under agreement5
Septic permits
Required countywide, administered by Portland Permitting & Development under an intergovernmental agreement6
Owner-builder
A narrow structural-code exemption is available, but the building permit still applies7
Minimum lot size (rural zones)
80 acres in Exclusive Farm Use, 20 acres in Multiple Use Agriculture, 5 acres in Rural Residential8910
RV living
Conditional on private land with owner consent, adequate water and sewage, and compliance with local standards11
Private wells
Landowners need a state permit, bond and fee to construct their own well; many domestic uses are exempt from a water-right permit1213
New-home occupancy
Portland-served projects need a certificate of occupancy before a new home, duplex or ADU is occupied14

Who to call

Building permits

Portland Permitting & Development

Building permits for some areas of unincorporated Multnomah County, under an intergovernmental agreement with the county

503-823-7300

Planning & zoning

Multnomah County Land Use Planning

Zoning and land-use review for most of unincorporated Multnomah County

503-988-3043

land.use.planning@multco.us

Septic permits

Portland Permitting & Development - Septic Permits

Septic (onsite wastewater) permits and inspections for all of Multnomah County under an intergovernmental agreement

503-823-6892

septic@portlandoregon.gov

Roads & driveways

Multnomah County Transportation Division

Driveway (road right-of-way access) permits for unincorporated Multnomah County roads

503-823-4000

Contact details are copied from each office’s official page and were checked against it on October 14, 2026.

Off-grid gear

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Do you need a building permit in unincorporated Multnomah County, Oregon?

Oregon requires a building permit to construct, enlarge, alter, repair or move a residential building or structure, including in unincorporated Multnomah County1. The Oregon Residential Specialty Code applies statewide to applicable work on one- and two-family dwellings and townhouses15. Multnomah County does not issue building permits; Portland Permitting & Development issues them for some unincorporated areas, while county Land Use Planning reviews building plans for zoning only, and septic permits stay with Portland's septic program countywide216. Other unincorporated pockets may be administered by neighboring cities, so ask Land Use Planning which jurisdiction serves the parcel before applying317. Certain detached, nonhabitable, one-story accessory structures under 200 square feet and under 15 feet in average roof height are exempt from a building permit, but electrical, mechanical or plumbing permits may still be required1. In Portland-administered areas, a new single-family home, duplex or accessory dwelling unit needs a Certificate of Occupancy or Temporary Certificate of Occupancy before anyone moves in14.

Who issues building permits and zoning approvals in Multnomah County, and how do you reach them?

Start with Multnomah County Land Use Planning at 503-988-3043 or land.use.planning@multco.us to confirm the parcel's jurisdiction and zoning17. When an owner applies for a building permit in an unincorporated area, the city refers the building plan to the county for zoning review; any required land-use permits must be approved before that plan is submitted16. The county requires digital, scaled plans through its customer portal, including the application, site plan, floor plan, elevations and service-provider review forms, and the assigned planner sends a status update in 30 days16. If Portland serves the parcel, contact Portland Permitting & Development at 503-823-7300 for the building permit18. The county fee schedule effective July 1, 2026 lists $527 for a zoning plan check and $1,620 for a floodplain development permit; notice charges, deposits or other fees may also apply19. Inside Troutdale, the city handles building permits; Portland's septic program still handles septic permits countywide204.

Does Multnomah County have zoning?

Multnomah County administers zoning for most unincorporated land, while some unincorporated pockets use city zoning under agreements21. County rural and Columbia River Gorge National Scenic Area zoning layers help identify the applicable rules; ask Land Use Planning to confirm the parcel’s designation2217. New-parcel minimums include 80 acres in Exclusive Farm Use, 20 acres in Multiple Use Agriculture and 5 acres in Rural Residential, subject to code exceptions8910. Meeting a minimum acreage does not replace land-division approval: rural subdivisions are Category 1 Land Divisions23.

Dimensional rules vary by district. In MUA-20, structures are limited to 35 feet in height, though barns, silos and similar structures may be taller if set at least 30 feet from every property line24; yards are 30 feet in front, 10 feet at the side, 30 feet at the street side and 30 feet at the rear25. In the Multiple Use Forest zone, a dwelling built after August 14, 1980 must have at least 600 square feet of floor area and sit on a foundation with a building permit26. In MR-4, lot coverage is capped at 40 percent27. Farm use and accessory buildings generally need no Significant Environmental Concern (SEC) permit, but agricultural buildings need SEC-wr and/or SEC-sw approval in the West of Sandy River Planning Area and SEC-s approval within Metro’s 2009 jurisdictional boundary; that exemption does not replace a building permit281.

How do septic permits work in Multnomah County?

Portland Permitting & Development administers septic permits and inspections throughout Multnomah County under agreements with the county and Oregon DEQ4. Where municipal sewer is unavailable, development must use onsite wastewater treatment, and the site needs enough usable space, required setbacks, adequate sewage-flow capacity, and suitable soil and water-table conditions29. Drainfield repairs, drainfield alterations and all new construction also need an approved Site Evaluation Report30. A licensed installer may build the system, or the property owner or owner's regular employee may do so after the septic installation permit is issued30. Complete applications are reviewed within 20 working days, and an application may be canceled if the applicant does not respond to a checksheet within 90 days30. Before final approval, every septic-tank permit needs an approved plumbing inspection of the sanitary line, plus approved electrical inspections when a pump is used31. Only about 1.5% of mapped county soils are rated “not limited” for a conventional drain field, so a site evaluation is essential; the soil rating does not mean septic is impossible32. Contact the septic program at 503-823-6892 or septic@portlandoregon.gov33.

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

Oregon allows camping-vehicle occupancy on private land with owner consent, adequate safe, approved water and sewage facilities, and compliance with applicable state and local installation standards11. Multnomah County zoning still controls the allowed use; ask Land Use Planning about the parcel before treating an RV as a residence2117. County-regulated campgrounds and RV parks allow temporary camping, not residential use; stays in MUA-20, RR, BRC, SRC and RC zones are limited to 90 days in any consecutive 12-month period unless state law provides otherwise, excluding the West of Sandy River and Urban Planning Areas3435. County-regulated ADUs cannot be RVs, park-model RVs, yurts or similar designs not intended for permanent occupancy, or structures unable to meet construction standards36. Those ADUs cannot be rented for fewer than 30 consecutive calendar days, and owners must record a covenant37. In Portland-administered Dunthorpe, Pleasant Valley, Southern Border, West County and West Hayden Island, only 1 occupied RV or tiny house on wheels is allowed on a residential lot with a house; none is allowed on undeveloped lots38. Manufactured homes are a separate question: Oregon allows occupying one on private land with the owner’s consent and adequate approved water and sewage39, while the county’s mobile home park rules in the LR-7 and LR-5 zones require a home built after June 15, 1976 with a state compliance insignia, set in a compliant mobile home space40. Outside those areas, we could not confirm a tiny-home primary-dwelling rule; ask Land Use Planning how the unit is classified17.

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

  1. Ask Multnomah County Land Use Planning to confirm jurisdiction, zoning and applicable overlays17322.
  2. Secure required land-use approval, then submit scaled digital plans for county zoning review through the customer portal16.
  3. Apply to the city issuing building permits for the address; call Portland Permitting & Development at 503-823-7300 when Portland serves the parcel218.
  4. Without sewer access, obtain a site evaluation and septic installation permit from Portland's countywide septic program30.
  5. An eligible owner-builder can claim a narrow ceiling-height, room-size and temperature exemption, but needs a building permit, must intend to occupy the home and must build the structural components personally or with unpaid friends and relatives7. The owner-builder statement and licensed-subcontractor requirements also apply41. In Portland, a homeowner doing electrical, plumbing or mechanical work personally can pull those trade permits, provided the building is not for sale, lease or rent; electrical permits add a six-month resale lookback and a penalty of up to $50042.
  6. Obtain a county driveway permit for new or altered access to a county road43.
  7. For Portland-issued building permits, schedule inspections before work is concealed; more than 180 days without an approved inspection causes expiration44.
  8. Before occupying a new home, duplex or ADU in a Portland-administered area, obtain a Certificate of Occupancy or Temporary Certificate of Occupancy14.

What should you check before buying land in Multnomah County?

Confirm jurisdiction and zoning first because the county, Portland and neighboring cities divide responsibility by parcel location317. Check septic feasibility early because only about 1.5% of mapped county soils are rated “not limited” for a conventional drain field32. If a private well is planned, a landowner who drills or alters it personally needs a state landowner permit, a $10,000 bond or letter of credit and a $550 fee before work begins12. Oregon generally requires a water-right permit to use groundwater, but domestic well use of no more than 15,000 gallons per day is among the listed exceptions13. Confirm access because a new or altered connection to a county road needs a driveway permit43. About 38.4% of Multnomah County is federal land, so verify private ownership and boundaries45. If buying land to split, confirm the land-division category with Land Use Planning rather than relying on acreage alone2317. The typical annual home-insurance premium is about $1,181, and the median property-tax bill is about $5,061 at an effective rate near 1%464748.

Watch-outs

  • Multnomah County does not issue building permits itself, and Portland's Permitting & Development bureau covers only some unincorporated areas; confirm which office actually serves your parcel before you assume county or Portland rules apply217.
  • Private-land camping-vehicle occupancy requires owner consent, adequate approved water and sewage, and compliance with local standards; county zoning may still limit the use115.
  • Only about 1.5% of Multnomah County's mapped soils are rated “not limited” for a conventional septic drain field; that does not rule out septic, but makes Portland's site evaluation essential before relying on a parcel for a home3230.
  • A farm-use exemption from an SEC permit has geographic exceptions for agricultural buildings and development; ask Land Use Planning about the overlay before planning a barn or other farm structure2817.

Sources

  1. About Oregon residential building permits, quoted and re-checked
  2. Submitting a Building Plan, quoted and re-checked
  3. County Urban Pocket Areas, quoted and re-checked
  4. Septic Permits: New Construction, Repairs, and Alterations, quoted and re-checked
  5. County Urban Pocket Areas (2026 county census)
  6. Portland Permitting & Development - Septic Permits (2026 county census)
  7. 2023 Oregon Residential Specialty Code, Chapter 1, quoted and re-checked
  8. multco.us, quoted and re-checked
  9. Chapter 39 – Multnomah County Zoning Code, quoted and re-checked
  10. Chapter 39 – Multnomah County Zoning Code, quoted and re-checked
  11. Oregon Revised Statutes, ORS 446.125 Occupancy on private land (Oregon statewide rule), quoted and re-checked
  12. Landowner Constructed Wells, quoted and re-checked
  13. Apply for a Water Use Permit, quoted and re-checked
  14. Residential Certificate of Occupancy and Temporary Certificate of Occupancy, quoted and re-checked
  15. Residential Structures Code Program, quoted and re-checked
  16. Submitting a Building Plan for Zoning Review, quoted and re-checked
  17. Multnomah County Land Use Planning (multco.us)
  18. Portland Permitting & Development (portland.gov)
  19. Land Use Planning Fees, quoted and re-checked
  20. Troutdale: How to Apply for a Permit (Multnomah County), quoted and re-checked
  21. County Urban Pocket Areas, quoted and re-checked
  22. LandUsePlanning/BaseZoning (MapServer), quoted and re-checked
  23. Chapter 39 – Multnomah County Zoning Code, quoted and re-checked
  24. Chapter 39 – Multnomah County Zoning Code, quoted and re-checked
  25. Chapter 39 – Multnomah County Zoning Code, quoted and re-checked
  26. Chapter 39 – Multnomah County Zoning Code, quoted and re-checked
  27. multco.us, quoted and re-checked
  28. Chapter 39 – Multnomah County Zoning Code, quoted and re-checked
  29. Housing and Onsite Wastewater Management, quoted and re-checked
  30. Septic Permits: New Construction, Repairs, and Alterations, quoted and re-checked
  31. Septic Permits: New Construction, Repairs, and Alterations, quoted and re-checked
  32. 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
  33. Portland Permitting & Development - Septic Permits (portland.gov)
  34. Chapter 39 – Multnomah County Zoning Code, quoted and re-checked
  35. Chapter 39 – Multnomah County Zoning Code, quoted and re-checked
  36. Chapter 39 – Multnomah County Zoning Code, quoted and re-checked
  37. Chapter 39 – Multnomah County Zoning Code, Multiple Use Agriculture, quoted and re-checked
  38. County Urban Pocket Areas, quoted and re-checked
  39. Oregon Revised Statutes, ORS 446.125 (Oregon statewide rule), quoted and re-checked
  40. Chapter 39 – Multnomah County Zoning Code — Mobile Home Park provisions, quoted and re-checked
  41. Information Notice to Owners About Construction Responsibilities (ORS 701.325(3)), quoted and re-checked
  42. Residential Inspections: The Start-to-Finish Guide, quoted and re-checked
  43. Permitting a Driveway, quoted and re-checked
  44. Residential Inspections: The Start-to-Finish Guide, quoted and re-checked
  45. Federal land share: Bolthole Index county data
  46. Typical home insurance premium: Bolthole Index county data
  47. Median property tax bill: Bolthole Index county data
  48. Effective property tax rate: Bolthole Index county data

Written October 14, 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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Compared with neighboring counties

Like all 6 of its neighbors, Multnomah County has countywide zoning.

RuleMultnomah CountyWashington CountyColumbia CountyClackamas CountyYamhill CountyMarion CountyHood River County
Building permitRequiredNot requiredRequiredRequiredLimitedRequiredRequired
County zoningYesYesYesYesYesYesYes
Septic permitsCity of Portland Permitting & DevelopmentCounty Env. HealthCounty Land Development ServicesCounty Septic ProgramCounty Planning & DevelopmentCounty Building InspectionCounty Env. Health

County locator

Multnomah County in Oregon

38
County map
Multnomah County highlighted among the Oregon counties · colored by Index score

How Multnomah County scores

Seclusion15100% ev.
Self-Sufficiency44100% ev.
Admin Boringness42100% ev.
Durability60100% ev.
Property Autonomy72100% ev.
Carry Cost29100% 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 →

$511kTypical home
1%Property tax
$27,472Land / acre
63.4"Annual rain
9.4% of yrsSevere drought
1.9 / yr (+1.5)Mid-century 100°F days
26.4 daysMid-century dry spell
2.24" (+3.9%)Mid-century 1-day rain
1.33×Wildfire change factor
100%Forward climate coverage
$1,181Home insurance / yr
3.2% / yrInsurance growth
0.55%Nonrenewal rate
county median (2+ published ZIPs)Insurance basis
1,457,701People within 30 min
3,825,009People within 2 hr
1,435,326Radius comparison (15 mi)
1,831.6People / sq mi
38.4%Federal land
55%Land at 15% slope or less
1.5%Soils rated "not limited" for septic (strict USDA rating)
3,096 acWorkable land screen
162.7 tonsBiomass / forest ac
51.8°FAvg temp

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Cities and towns in Multnomah County

Inside a city or town, that city usually issues building permits and sets zoning; the county’s rules above cover unincorporated land. Septic, wells and floodplain rules usually stay with the county or state everywhere.

Not yet researched: Fairview · Gresham · Maywood Park · Portland

Answers from the rulebook for Multnomah County

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

Multnomah County rules

  • Building permitLimited

    Building permits in unincorporated Multnomah County; the issuing city depends on the area, and Portland issues permits for some unincorporated areas.

    • Multnomah County states that it does not issue building permits.
    • Building permits in Multnomah County are issued by cities, including for areas outside city boundaries.
    • Portland's page expressly limits its role to some areas of unincorporated Multnomah County.
    “The City of Portland also issues building permits for Some areas of unincorporated Multnomah County”
  • InspectionsRequired

    Permitted residential construction in unincorporated Multnomah County where the issuing jurisdiction requires the listed inspections; Portland's residential inspection rules apply to permits administered by Portland Permitting & Development.

    • All permitted work must be inspected before it is covered by drywall, concrete, backfill, or similar concealment.
    • New construction follows a full inspection sequence beginning with erosion control and foundation inspections and ending with final inspections.
    • All permits need the 999 Final Permit inspection; a permit is not approved and closed until that inspection is completed.
    • If a permit is without an approved inspection for more than 180 days, it will expire.

    permit inspection expiration without approved inspection: 180 days

    “All permitted work must be inspected before it is covered by drywall, concrete, backfill, etc.”
  • Certificate of occupancyLimited

    New single-family dwelling units, duplexes, and accessory dwelling units in areas of unincorporated Multnomah County administered under the Portland residential certificate-of-occupancy program.

    • Either a Certificate of Occupancy or Temporary Certificate of Occupancy is required before occupancy of all new residential construction of single-family dwelling units, duplexes, and accessory dwelling units.
    • Certificates of Occupancy and Temporary Certificates of Occupancy are not required for residential additions, alterations, or accessory structures such as garages.
    • A Certificate of Occupancy is issued after final inspections for all requirements related to the permitted project are inspected and approved.
    • A Temporary Certificate of Occupancy may be requested when not all permitted work is complete, but minimum fire and life-safety requirements, applicable temporary erosion control, required discipline approvals, and the issuance fee must be satisfied.

    temporary certificate duration: 30 days (Extensions may be granted for a maximum of 30 days each under the program guide.)

    “Either a C of O or TCO is required prior to occupancy of all new residential construction of single family dwelling units, duplexes, and accessory dwelling units.”
  • County-wide zoningPresent (with conditions)

    County zoning in Multnomah County, principally the unincorporated areas outside cities.

    • Multnomah County is responsible for zoning in most unincorporated areas.
    • Some unincorporated areas are administered by neighboring cities under intergovernmental agreements and have city zoning.
    • Incorporated municipalities administer their own zoning.
    “Multnomah County is responsible for zoning in most unincorporated areas of the County. Unincorporated areas are those areas located outside of a city.”
  • Local zoningVaries (with conditions)

    The county aggregate of local zoning across incorporated municipalities and unincorporated areas of Multnomah County.

    • The county administers zoning in most unincorporated areas.
    • Some unincorporated areas have city zoning administered by neighboring cities under IGAs.
    • The City of Portland administers the Portland Zoning Code for specific areas of unincorporated Multnomah County.
    • Property-specific jurisdiction and zoning must be verified using the county jurisdiction map or with the responsible planning authority.
    “Some unincorporated areas are administered by neighboring cities and have city zoning. These areas are determined through Intergovernmental Agreements (IGAs) and are known as IGA areas.”
  • Zoning districtsPublished

    Published GIS zoning layers for Multnomah County land-use zoning, including the Rural Zoning and Columbia River Gorge National Scenic Area Zoning layers.

    • The GIS service is a publication of zoning data layers and does not by itself determine the zoning designation of a particular parcel.
    • The county zoning code and applicable Columbia River Gorge National Scenic Area regulations may apply to different areas.
    “Service Description: GIS data layers used for Land Use Zoning in Multnomah County, Oregon Map Name: BaseZoning Layers: * Rural Zoning - Multnomah County (0) * Col. River. Gorge Natl. Scenic Area Zoning (1)”
  • Minimum dwelling sizeDistrict specific (with conditions)

    Residential uses located in the Multnomah County Multiple Use Forest (MUF) base zone after August 14, 1980.

    • The dwelling must comply with the listed MUF residential development standards.
    • The dwelling must be attached to a foundation for which a building permit has been obtained.
    • The dwelling must be outside a big game habitat area unless the Oregon Department of Fish and Wildlife certifies acceptable impacts.

    minimum floor area: >= 600 square feet

    “A residential use located in the MUF base zone after August 14, 1980, shall comply with the following: [...] The dwelling shall have a minimum floor area of 600 square feet.”
  • Minimum lot sizeSpecified

    New parcels in the Exclusive Farm Use (EFU) base zone.

    • The rule has an exception for MCC 39.3070.
    • The EFU dimensional and development standards also apply.

    minimum lot size: >= 80 acres (Except as provided in MCC 39.3070)

    “Except as provided in MCC 39.3070, the minimum lot size for new parcels shall be 80 acres in the EFU base zone.”
    2 more reviewed findings on this topic
    • Specified — New parcels or lots in the Multiple Use Agriculture (MUA-20) base zone.
      “Except as provided in MCC 39.3080, 39.4330, 39.4335 and 39.5300 through 39.5350, the minimum lot size for new parcels or lots shall be 20 acres.”
    • Specified — New parcels or lots in the Rural Residential (RR) base zone.
      “Except as provided in MCC 39.3090, 39.4380, 39.4385 and 39.5300 through 39.5350, the minimum lot size for new parcels or lots shall be five acres.”
  • SetbacksSpecified

    Development in the MUA-20 base zone.

    • Accessory structures may encroach up to 40 percent into a required yard only when the yard is not contiguous to a road, the structure does not exceed five feet in height or a ten-square-foot footprint, and fire-code compliance is demonstrated.
    • A variance is required for an accessory structure encroaching more than 40 percent.
    • Minimum yards increase where the yard abuts a street with insufficient right-of-way width.
    • Agricultural structures may have a reduced rear yard to 10 feet under the stated dwelling-separation conditions.

    front yard: >= 30 feet · side yard: >= 10 feet · street-side yard: >= 30 feet · rear yard: >= 30 feet (Agricultural structures may qualify for a reduced rear yard of 10 feet under MCC 39.4325(F))

    “Minimum Yard Dimensions – Feet Front Side Street Side Rear 30 10 30 30”
  • Lot coverageSpecified

    Development in the MR-4 base zone.

    • The MR-4 dimensional requirements include exceptions under MCC 39.3140(B) and 39.4910(A)-(B).

    maximum lot coverage: <= 40 percent

    “The maximum lot coverage shall be 40 percent.”
  • Building heightSpecified

    Structures in the MUA-20 base zone.

    • Structures such as barns, silos, windmills, antennae, chimneys, or similar structures may exceed the height requirement if located at least 30 feet from any property line.

    maximum structure height: <= 35 feet (Certain structures may exceed the limit if at least 30 feet from any property line)

    “Maximum Structure Height – 35 feet [...] structures may exceed the height requirement if located at least 30 feet from any property line.”
  • Living in an RVTemporary only (with conditions)

    Recreational vehicle occupancy in a county-regulated campground, campsite, or recreational vehicle park in applicable unincorporated Multnomah County zoning districts.

    • The campground definition allows recreational vehicle occupancy for overnight temporary vacation, recreational, or emergency purposes, but not residential purposes.
    • In MUA-20, RR, BRC, SRC, and RC base zones, the stay by a person or vehicle in a camp, campground, campsite, or recreational vehicle park may not exceed 90 days in any consecutive 12-month period unless otherwise provided in state law.
    • The 90-day provision does not apply in the West of Sandy River Planning Area or Urban Planning Area.
    • Camp, campground, and recreational vehicle park uses may require approval under the applicable base zone and planning-area provisions.

    maximum stay: <= 90 days in any consecutive 12-month period (Unless otherwise provided in state law; not applicable in the West of Sandy River Planning Area or Urban Planning Area)

    “the length of stay by a person or vehicle in a camp, campground, campsite or recreational vehicle park shall not exceed a total of 90 days during any consecutive 12 month period”
  • Camping on your landLimited

    Temporary camping in county-regulated camps, campgrounds, campsites, and recreational vehicle parks in applicable unincorporated Multnomah County zoning districts.

    • Camping is defined for overnight temporary vacation, recreational, or emergency purposes.
    • A campsite may be occupied by a tent, travel trailer, or recreational vehicle, but not for residential purposes.
    • In MUA-20, RR, BRC, SRC, and RC base zones, stay is limited to 90 days in any consecutive 12-month period, subject to state-law exceptions.
    • The 90-day rule does not apply in the West of Sandy River Planning Area or Urban Planning Area.

    maximum stay: <= 90 days in any consecutive 12-month period (Unless otherwise provided in state law; excluded planning areas stated above)

    “Campground – An area improved with a campsite and/or used for an overnight temporary stay for vacation, recreational or emergency purposes”
  • Tiny homesProhibited

    A tiny-home design that is a recreational vehicle, park model recreational vehicle, yurt, or similar design not intended for permanent human occupancy when proposed for use as an accessory dwelling unit under Multnomah County zoning.

    • The cited ADU standards apply to the relevant Multnomah County zoning base zone and not necessarily to areas administered by a neighboring city under an intergovernmental agreement.
    • The ADU must be sited entirely inside the urban growth boundary.
    • The ADU may not be accessory to a health hardship dwelling or any other type of temporary dwelling.
    • Transportation impacts must be mitigated under the Multnomah County Road Rules.
    • The ADU must use the same lawfully established driveway entrance as the single-family dwelling, although the driveway may be extended to the ADU.
    • No variance, adjustment, deviation, or other modification is allowed for the shared-driveway provision.
    • The ADU floor area may not exceed 800 square feet or 75% of the floor area of the single-family dwelling to which it is accessory, whichever is less.
    • An attached or interior ADU must include at least one separate exterior doorway to the outside.
    • The prohibited designs include recreational vehicles, park model recreational vehicles, yurts, other similar designs not intended for permanent human occupancy, and structures unable to meet all applicable construction or installation standards.
    • Short-term rental of the ADU is prohibited; short-term rental means fee-based occupancy for less than 30 consecutive calendar days, while month-to-month rental agreements for long-term purposes are not short-term rentals.
    • The land owner must sign and record a county covenant stating that the ADU cannot be used for short-term rental; the covenant applies until the property is annexed into a city and is no longer subject to county land-use regulations.

    maximum ADU floor area: <= 800 square feet (or 75% of the floor area of the associated single-family dwelling, whichever is less) · short-term rental period: < 30 consecutive calendar days (month-to-month long-term rental agreements are not short-term rentals)

    “The following designs are not permitted for use as an ADU: Recreational vehicle, park model recreational vehicle, yurt or any other similar design not intended for permanent human occupancy or any structure unable to meet all applicable construction or installation standards.”
  • Manufactured homesLimited

    Permanent occupancy of manufactured homes in county-regulated mobile home parks in applicable unincorporated Multnomah County residential base zones.

    • The manufactured home must be located in a compliant mobile home space.
    • In LR-7 and LR-5 base zones, it must have been constructed after June 15, 1976 and carry a state insignia showing compliance with applicable Oregon mobile-home construction or equipment standards.
    • The home must meet state construction standards evidenced by the required insignia.
    • Other park standards include potable water and electrical and sewage-disposal connections, space-coverage limits, and separation distances.

    construction date: > 1976-06-15 · minimum floor area: >= 800 square feet (For mobile homes in mobile home parks within LR-7 or LR-5 base zones; other zone-specific standards may differ)

    “Any mobile home in a mobile home park within an LR-7 or LR-5 base zone shall: (1) Be located in a mobile home space”
  • Septic permitRequired

    Septic permitting and inspections for all of Multnomah County, including incorporated and unincorporated areas, for properties using septic systems rather than public sewer.

    • The City of Portland administers the program under an intergovernmental agreement with Multnomah County and the Oregon Department of Environmental Quality.
    • The City of Portland oversees administration of Oregon DEQ On-Site Wastewater Treatment Systems Rules.
    • Septic systems are used where properties do not have physical or legal access to a public sewer.
    • New construction, repairs, and alterations require the applicable septic installation permit; repair and alteration of drainfields and all new construction require an approved Site Evaluation Report.
    • A certified septic installer working for a DEQ-Licensed Onsite System Installer Business, or alternatively the property owner or the property owner's regular employee, may construct or install the system only with an issued septic installation permit.
    • Complete applications are reviewed within 20 working days; applications may be cancelled after 90 days without response to a checksheet, and new fees apply.
    • For all septic tank permits, an approved plumbing inspection for the sanitary line is required before finalization; if a pump is required, an approved electrical inspection is also required before the septic final.

    plan review period: 20 working days · application checksheet response period: 90 days (Applications are cancelled if no response is received; new fees apply.)

    “Alternatively, the property owner or the property owner's regular employee may construct or install a septic system with an issued septic installation permit.”
  • Agricultural exemptionConditional

    Farm use, including buildings and structures accessory to farm use, under the Significant Environmental Concern overlay provisions of Chapter 39.

    • Farm use and accessory buildings generally do not require an SEC permit.
    • Within the West of Sandy River Planning Area, an SEC-wr and/or SEC-sw permit is required for agricultural buildings, structures, and development associated with farm practices and agricultural uses; agricultural fences are excepted.
    • Within Metro’s 2009 jurisdictional boundary, an SEC-s permit is required for agricultural buildings, structures, and development associated with farm practices and agricultural uses; agricultural fences are excepted.
    • The code defines farm use by reference to ORS 215.203(2)(a).
    “Farm use, as defined in ORS 215.203(2)(a), including buildings and structures accessory to a farm use do not require an SEC permit except in the following situations:”
  • Subdividing landRegulated (with conditions)

    Subdivisions and other land divisions in unincorporated Multnomah County subject to Chapter 39.

    • Every land division must comply with applicable MCC 39.9505 through 39.9585 standards.
    • A rural area subdivision is a Category 1 Land Division.
    • An urban area subdivision of more than 10 lots is a Category 1 Land Division.
    • Urban subdivisions of 10 lots or less and partitions are assigned categories based on street, impact, overlay, and other criteria.

    urban subdivision threshold for Category 1: > 10 lots (Urban subdivision of 10 lots or less may be Category 1 when specified street or impact criteria apply)

    “Every land division proposal shall comply with the applicable provisions of MCC 39.9505 through 39.9585.”
  • Driveway accessRequired

    Any new or altered access to a Multnomah County road, including driveway access in unincorporated areas.

    • Some older driveways that never received a permit may need to be brought into compliance.
    • The application requires a right-of-way permit application, site plan, proof of insurance, traffic-control plan, permit fee, and driveway deposit payment.
    • A traffic-control plan conforming to MUTCD standards is required if the work is expected to interrupt or affect traffic.
    • A deposit is required when paving or repaving a driveway and is refunded after construction passes inspection.
    • The county says permits usually take about three weeks.

    typical processing time: about three weeks

    “A driveway permit is required for any new or altered access to a county road. In addition, some older driveways may have never received a permit and may need to be brought into compliance.”
  • Short-term rentalsLimited

    Accessory dwelling units regulated under the cited Multnomah County Zoning Code provision in unincorporated county areas.

    • Short-term rental means fee-based occupancy for fewer than 30 consecutive calendar days.
    • Month-to-month rental agreements for long-term purposes are excluded from the definition.
    • The property owner must sign and record a covenant with the county stating that the ADU cannot be used for short-term rental.
    • The covenant applies until the property is annexed into a city and is no longer subject to county land-use regulations.
    • This source establishes an ADU-specific restriction, not a blanket countywide prohibition on every short-term rental.

    short-term rental maximum duration: < 30 consecutive calendar days (Month-to-month long-term rental agreements are excluded)

    “Short-term rental of the ADU is prohibited. For purposes of this subsection, short-term rental is defined as fee-based occupancy for a period less than 30 consecutive calendar days. Month-to-month rental agreements for long-term purposes are not short-term rental.”
  • Permit feesPublished (with conditions)

    Multnomah County Land Use Planning fees for applications in unincorporated county areas.

    • The fee schedule is effective July 1, 2026.
    • The published schedule includes a Floodplain Development Permit fee of $1,620 and a Zoning Plan Check fee of $527.
    • Applications are not identified as received until full payment is made; payment after 4:00 PM or outside regular business hours is received the next business day.
    • Some Type II, III, and IV applications require notice fees, deposits, or full-recovery deposits; the Planning Director may require a full recovery deposit estimate when projected costs exceed the listed minimum.

    Floodplain Development Permit fee: 1620 USD · Zoning Plan Check fee: 527 USD · effective date: 2026-07-01

    “Multnomah County Land Use fee schedule effective July 1, 2026. [...] Floodplain Development Permit | $1,620 [...] Zoning Plan Check (new development, or new development and demo permit, or other site plan review) | $527”
  • Permit processPublished (with conditions)

    Building-plan and zoning-review process for building permits in unincorporated parts of Multnomah County.

    • The city refers applicants to Multnomah County Land Use Planning for building-plan zoning review.
    • If the project requires land-use permits, those permits must be approved before building plans are submitted for zoning review.
    • Required documents include an application form, site plan, floor plan, building elevations, service-provider review forms, and other information identified in the zoning checklist or land-use permit.
    • Documents must be submitted digitally and plans must be drawn to scale.
    • Plans are submitted through the customer portal using the Zoning Plan Review application option.
    • The application is not considered received until full payment is made; payment after 4:00 PM or outside regular business hours is received the next business day.
    • The assigned planner sends a status update in 30 days.
    • The City of Portland administers the Portland Zoning Code for specific areas of unincorporated Multnomah County.
    “When you apply for a building permit in unincorporated parts of the county, the city will refer you to us to submit your building plan. We will review it for compliance with zoning rules.”

Oregon rules that apply here

  • Owner-builder exemptionAvailable (with conditions)

    Owner-built single-family residences and adjacent auxiliary structures in Oregon, including Multnomah County, when the statutory owner and construction conditions are met.

    • The owner must be the owner of title or contract purchaser of record and must not have used the exemption during the five years before applying.
    • The owner-built dwelling and outbuildings must be a single-family residence and adjacent auxiliary structures whose structural components are constructed entirely by the owner, or by the owner and unpaid friends and relatives, and the owner must intend to occupy the structures.
    • The exemption applies only to structural-code requirements for ceiling heights, room sizes, and maintenance of specific temperature levels.
    • The exemption applies to new construction, renovation, remodeling, or alteration of an owner-built dwelling or outbuilding.
    • A building permit issued for the owner-built dwelling or outbuilding must note whether it complies with the exempted requirements.
    • If it does not comply, the owner-builder must file a copy of the building permit with the county clerk for permanent deed recording and provide a sufficient property description.
    • This exemption does not eliminate the building-permit requirement.

    prior use lookback period: 5 years

    “Owner-built dwellings and outbuildings shall be exempt from any requirements of the structural code for ceiling heights, room sizes and the maintenance of specific temperature levels in those structures.”
    2 more reviewed findings on this topic
    • Available (with conditions) — Residential building, electrical, mechanical, and plumbing permits for an owner-builder in Multnomah County under Oregon law.
      “This statement is required for residential building, electrical, mechanical, and plumbing permits. This statement will be filed with the permit.”
    • Available (with conditions) — Owner-built single-family residences and adjacent auxiliary structures in Oregon where the structural components are constructed entirely by the owner intending to occupy the structures, or by the owner with unpaid assistance from friends and relatives.
      “Owner-built dwellings and outbuildings shall be exempt from any requirements of the structural code for ceiling heights, room sizes”
  • Building code adoptedAdopted (with conditions)

    The Oregon Residential Specialty Code applies statewide to construction, reconstruction, and repair of one- and two-family dwellings and townhouses, including applicable projects in Multnomah County.

    • Administrative provisions, Chapter 1, were effective and mandatory October 1, 2023.
    • Construction provisions, Chapters 2-44 and appendices, were effective October 1, 2023 with a six-month phase-in period and became mandatory April 1, 2024.
    • The cited ORSC page states the code is based on the 2021 International Residential Code.
    • This claim addresses the statewide residential code; other building types may be governed by other Oregon specialty codes.

    administrative provisions mandatory date: 2023-10-01 · construction provisions effective date: 2023-10-01 (six-month phase-in period) · construction provisions mandatory date: 2024-04-01

    “Construction provisions (Chapters 2 - 44 and appendices): Effective Oct. 1, 2023 with six-month phase-in period Mandatory April 1, 2024”
    3 more reviewed findings on this topic
    • Adopted (with conditions) — Oregon State Building Code specialty codes administered statewide by the Oregon Building Codes Division.
      “The Building Codes Division adopts, amends, and interprets specialty codes that make up the Oregon State Building Code.”
    • Adopted (with conditions) — Commercial construction, reconstruction, alteration, and repair governed by the Oregon Structural Specialty Code statewide.
      “Construction provisions: [...] Mandatory April 1, 2026”
    • Adopted (with conditions) — Construction, reconstruction, and repair of one- and two-family dwellings and townhouses governed by the Oregon Residential Specialty Code statewide.
      “2023 Oregon Residential Specialty Code (ORSC) [...] Based on 2021 International Residential Code (IRC)”
  • Accessory dwellingsLimited

    Accessory dwelling units in areas within an urban growth boundary zoned for detached single-unit dwellings in a city with population greater than 2,500 or a county with population greater than 15,000.

    • The local government must allow at least one accessory dwelling unit for each detached single-unit dwelling.
    • Local regulations may address siting and design but may not include owner-occupancy requirements for the primary or accessory structure or requirements to construct additional off-street parking.
    • Local governments may regulate vacation occupancies to require owner-occupancy or off-street parking.

    city population threshold: > 2500 persons · county population threshold: > 15000 persons · minimum ADUs per detached single-unit dwelling: >= 1 unit

    “A city with a population greater than 2,500 or a county with a population greater than 15,000 shall allow”
  • Who permits septicMixed

    Residential and small-business septic permitting statewide in Oregon.

    • DEQ directly permits residential and small-business septic systems in Curry, Jackson, and Josephine counties.
    • In Oregon's other 33 counties, DEQ contracts with local jurisdictions for residential and small-business septic permitting.
    “The Oregon Department of Environmental Quality permits residential and small business septic systems in Curry, Jackson, and Josephine counties out of the DEQ Medford Office. In Oregon's other 33 counties, DEQ has contracts with local jurisdictions for residential and small business septic permitting.”
  • Off-grid sanitationLimited

    Use of composting toilets and related graywater systems in Oregon.

    • A composting toilet does not eliminate all household water; plumbing fixtures still need connection to an approved septic system.
    • If used with a graywater reuse system, both the graywater reuse system and septic system require a DEQ permit.
    • The graywater reuse system must be offline during wet-weather months or when discharges could create a public nuisance.
    • Material removed from a composting toilet must be buried under 12 inches of soil.
    • Buildings within a sewer district still need a sewer connection.

    burial depth for removed composting-toilet material: 12 inches · maximum reduced drainfield capacity mentioned by DEQ: two-thirds (The source says the drainfield may be approved for a smaller capacity, as much as two-thirds the size.)

    “Composting toilets don't eliminate all water generated in a home and therefore you will need to be hooked up to an approved wastewater treatment system.”
    One more reviewed finding on this topic
    • Allowed (with conditions) — Development using onsite wastewater treatment or septic systems where municipal sewer is unavailable in Multnomah County.
      “In areas where a municipal sewer system is not available, development must use onsite wastewater treatment systems, or septic systems, for sanitary disposal.”
  • Well permitRequired

    A property owner constructing, altering, converting, or abandoning a water-supply well in Oregon without being a licensed and bonded Water Supply Well Constructor.

    • A licensed and bonded Water Supply Well Constructor is exempt from the landowner-permit requirement stated on the page.
    • The permit, permit fee, and bond or irrevocable letter of credit must be obtained before work begins.
    • The application requires owner and surety information, proposed well location, proposed use, type of work, and a Department-approved well design plan.
    • The bond or irrevocable letter of credit is $10,000 and the permit fee is $550.
    • Only the owner of record, an immediate family member of the owner of record, or a full-time employee whose main duties are other than well construction may operate a drilling machine under a landowner permit.
    • The permit expires six months after issuance; a water-well report is due within 30 days after permit expiration or well completion, whichever occurs first.
    • The Department may deny a permit if the proposed work presents a health threat, health hazard, contamination source, or groundwater waste source.

    bond or irrevocable letter of credit: 10000 USD · permit fee: 550 USD · permit expiration: 6 months · water-well report deadline: 30 days (after permit expiration or well completion, whichever occurs first)

    “The Water Resources Commission requires a permit [...] for each water supply well constructed, altered, converted, or abandoned by a landowner”
    2 more reviewed findings on this topic
    • Limited — Construction, alteration, conversion, or abandonment of a water supply well by a landowner in Multnomah County under Oregon statewide well-construction rules.
      “The landowner permit and bond shall be obtained prior to beginning work on a well.”
    • Limited — Use of groundwater from a well in Multnomah County under Oregon water-right permitting rules.
      “With some exceptions, a water right permit or license from the Oregon Water Resources Department (Department) is required to use water from any source”
  • Mandatory utility hookupSewer (with conditions)

    A building located within an Oregon sewer district, including a building using a composting toilet.

    • The source specifically addresses buildings within a sewer district.
    • A composting toilet does not eliminate the sewer-connection requirement.
    “What if my building is within a sewer district? Your building will still need a sewer connection.”
  • county zoning authorityGeneral

    Oregon counties adopting and revising comprehensive plans, zoning, subdivision, and other land-use ordinances applicable to county land, including unincorporated areas.

    • The statutory text states an exception for ORS 527.722.
    • Plans and related ordinances may be adopted and revised part by part or by geographic area.
    • Zoning, subdivision, and other ordinances or regulations must be designed to implement the adopted county comprehensive plan.
    • Before a county zoning ordinance has legal effect, the governing body or planning commission must conduct one or more public hearings and publish 10 days' advance public notice; additional notice requirements apply to certain zone changes under ORS 215.223.
    “Except as provided in ORS 527.722, the county governing body shall adopt and may from time to time revise a comprehensive plan and zoning, subdivision and other ordinances applicable to all of the land in the county. The plan and related ordinances may be adopted and revised part by part or by geographic area.”
  • county building authorityGeneral

    Oregon counties administering and enforcing building inspection programs, including issuance and enforcement of building permits for residential construction in areas outside incorporated cities.

    • A county building inspection program is subject to the state building code and the statutory building-inspection-program framework.
    • If a county does not notify the director, or notifies the director that it will not administer and enforce a building inspection program, the director must arrange administration and enforcement through a municipality, other person, state employees, or state agencies; permit and other fees arising therefrom are paid into the Consumer and Business Services Fund.
    • A building inspection program is administered for four-year periods under ORS 455.150; the governing body must provide required notices to the Director of the Department of Consumer and Business Services.
    • The program must specify cooperation with the State Fire Marshal or designee and how a uniform fire code will be considered in design and construction review.
    • The cited archive is the 2015 Oregon Revised Statutes edition; the current official ORS 455 page was identified but returned a 403 error during retrieval.
    “If a city does not notify the director, or notifies the director that it will not administer the building inspection program, the county or counties in which the city is located shall administer and enforce the county program within the city in the same manner as the program is administered and enforced outside the city, except as provided by subsection (6) of this section.”

Inside cities and towns in Multnomah County

Municipal rules found while researching the county. They apply inside that city or town, not to unincorporated land.

  • Owner-builder exemptionAvailable (with conditions)

    Homeowners performing residential trade work themselves in the City of Portland.

    • The homeowner may obtain required electrical, plumbing, and mechanical trade permits when doing the trade work personally.
    • The building must not be for sale, lease, or rent.
    • If a subcontractor performs the work, the subcontractor must obtain the subcontractor's own permits.
    • For electrical work, Portland Code 26.04.030 additionally requires code-compliant wiring, performance by the owner or an immediate family member as defined in OAR, and no intent to sell, exchange, lease, or rent the property.
    • If the property is offered for sale, exchange, lease, or rent within six months after final approval, Portland code creates a rebuttable presumption of intent and permits a penalty of up to $500.
    • If a condition is not met, the electrical permit may be revoked under Portland Code 26.04.090.

    sale, exchange, lease, or rent lookback period: 6 months after final approval (Creates a rebuttable presumption of intent under Portland Code 26.04.030.) · maximum penalty: <= 500 USD (Applies if the property is offered for sale, exchange, lease, or rent within six months after final approval and the City Administrator determines the owner intended that use when the permit was issued.)

    “If you own the property and plan to do the trade work yourself, you can get the required trade permits as a homeowner.”
  • Tiny homesLimited

    Occupied tiny houses on wheels in the Portland-administered unincorporated Multnomah County IGA areas, including Dunthorpe, Pleasant Valley, Southern Border, West County, and West Hayden Island.

    • The unit must be a constructed tiny house built on a trailer with wheels and must remain mobile with the wheels attached.
    • It must be inhabited and parked on a developed residential lot with a primary dwelling unit, house, attached house, or manufactured home.
    • Only one occupied recreational vehicle or tiny house on wheels is allowed on a residential lot with a house, attached house, or manufactured home; up to four occupied recreational vehicles are allowed in the parking lots of religious institutions.
    • Occupied recreational vehicles and tiny houses on wheels are not permitted on undeveloped lots.
    • Applicable recreational-vehicle parking requirements apply; the page generally requires a tiny house on wheels with a motor to be parked on a paved surface and not in front of the street-facing facade of the primary dwelling.
    • The unit does not count toward residential density, and in most cases house, attached-house, and manufactured-home development standards do not apply.
    • A tiny house on wheels may not be used as an accessory short-term rental.
    • The vehicle must be parked at least five feet from the primary dwelling.
    • Electrical connections are required through a dedicated outlet on a service pedestal or the primary dwelling; the circuit must be a minimum 20-amp GFCI-protected dedicated circuit, and an electrical permit is required if the circuit is not already installed.
    • If the vehicle has internal plumbing, it must be connected to potable water and sanitary sewer services; a plumbing permit is required for a sewer connection. If it lacks internal plumbing, occupants must have access to potable water, toilets, and showers in the primary house.

    maximum occupied tiny houses on wheels per residential lot with a house, attached house, or manufactured home: 1 unit (Up to four occupied recreational vehicles are allowed in the parking lots of religious institutions.) · minimum separation from primary dwelling: >= 5 feet · minimum dedicated electrical circuit: >= 20 amps (GFCI-protected and dedicated; electrical permit required if circuit is not already installed.)

    “Only one occupied recreational vehicle or tiny house on wheels is allowed on a residential lot with a house, attached house or manufactured home. Up to four occupied recreational vehicles are allowed in the parking lots of religious institutions. Occupied recreational vehicles, including tiny houses on wheels, are not permitted on undeveloped lots.”
  • Who permits septicLocal

    Septic permitting and inspections throughout Multnomah County, including incorporated cities and named communities listed by the City of Portland.

    • The City of Portland administers the program under an intergovernmental agreement with Multnomah County and Oregon DEQ.
    • The City of Portland oversees administration of DEQ’s On-Site Wastewater Treatment Systems Rules.
    “The City of Portland has an intergovernmental agreement with Multnomah County and the State of Oregon Department of Environmental Quality (DEQ) to conduct septic permitting and inspections for all of Multnomah County”
  • Septic inspectionRequired

    Septic permits administered by Portland Permitting & Development for Multnomah County.

    • The City of Portland conducts septic inspections for all of Multnomah County under its intergovernmental agreement.
    • For all septic tank permits, an approved plumbing inspection for the sanitary line is required before the septic permit is final.
    • If a pump is required, approved electrical inspections are required for underground trenching and the septic panel before septic final.
    • Inspection schedules differ east and west of the Willamette River.

    septic tank inspection code: 836 · drainfield inspection code: 814

    “For all septic tank permits, an approved Plumbing inspection for the sanitary line is required before the septic permit is final.”

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 Multnomah County, Oregon

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

Multnomah County scores 38/100 on the Bolthole Index, a marginal county profile. Its strengths: a stronger property-autonomy legal backdrop and mixed durability signals. Watch-outs: little seclusion — roughly 1,457,701 people within a 30-minute drive and higher long-term carry cost.

Do you need a building permit in Multnomah County, Oregon?

Multnomah County generally requires a residential building permit, and it enforces county zoning. Onsite septic is permitted by City of Portland Permitting & Development (administering Oregon DEQ Onsite Wastewater rules via IGA). 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 Multnomah County?

Living in an RV on your own land in Multnomah County is limited to specific cases: Statewide rule. One residential-use recreational vehicle on a lot or parcel in an Oregon rural area, when a county elects to allow the use under ORS 215.490. The property must not be within an urban reserve. An owner-occupied single-unit dwelling must be sited on the property as the owner's primary residence. A tiny home is prohibited. Confirm with the county before relying on it.

How much does land cost in Multnomah County, Oregon?

Land in Multnomah County runs about $27,472 per acre, based on the latest county data.

What is the water situation in Multnomah County?

Multnomah County gets about 63.4" of rain a year, with severe drought in roughly 9.4% of years.

How remote is Multnomah County?

A representative private-land location has about 1,457,701 people within a 30-minute drive and 3,825,009 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.

How Multnomah compares in Oregon

Compare side-by-side →See all 36 Oregon counties ranked →