ADU Pass
Borrego Springs
ADU Pass helps homeowners in Borrego Springs, San Diego County, California navigate the permit paperwork for building an accessory dwelling unit. This area covers 1 ZIP code.
Map
ADU details
ADU legality: allowed
Allowed by-right ministerial under state law as administered by County PDS. The Borrego Springs Community Plan lighting / dark-sky standards add review of exterior lighting design but do not bar ADU development.
Cost scenarios
| Scenario | Sq ft | Permit | Build | Total |
|---|---|---|---|---|
| minimum | 150 | $1,730 | $51,000 | $52,730 |
| 600 | 600 | $2,008 | $204,000 | $206,008 |
| midpoint | 675 | $2,080 | $229,500 | $231,580 |
| maximum | 1,200 | $3,768 | $408,000 | $411,768 |
Fee breakdown (as of 2026-04)
Permitting process
- (~2d)
- (~5d)
- (~1d)
- (~35d)
- (~14d)
- (~21d)
- (~3d)
Viability (permitted uses)
- Long-term rental: yes Long-term rental is by-right; California owner-occupancy preemption in effect since 2024 makes ADUs eligible for full landlord-tenant treatment.
- Short-term rental: with-restrictions San Diego County's STRO ordinance (Title 2, Div. 1, Ch. 8) does not apply to unincorporated areas as of 2026; Borrego Springs STR activity is strong (resort/snowbird market, March wildflower season) but new properties should confirm with PDS. Property-tax classification and TOT remit to County Treasurer.
- Office rental: with-restrictions External office tenant rental of an ADU requires a Minor Use Permit / home-occupation review; not a by-right ADU use under the County ordinance.
- Home office: yes Owner home-occupation use permitted with the standard County home-occupation rules (no employees on-site, no signage, limited customer traffic).
- Studio / workshop: yes Personal artist/studio use of an ADU is a permitted accessory residential use; Borrego is a noted plein-air desert painting community.
- Agriculture: with-restrictions ADU on an A70 / A72 agricultural-zoned parcel is permitted but the ADU itself is a residential accessory use, not an agricultural structure. Greenhouse / packing-shed accessory structures are a separate permit.
- Relative support: yes Multigenerational / relative-occupancy ADU is permitted. Owners should file a Rev. & Tax. Code 74.3 Claim for New Construction Exclusion at permit issuance to preserve the parent/child intergenerational-housing exclusion.
Incentives
- Unincorporated green-design fee discount (7.5% off PDS permit-related fees)
- ADU separate-sale condo conversion program (post-March 2026)
Pre-approved plans Pre-approved plans
Contacts
Staff: PDS Zoning Permit Counter (ADU pre-application zoning consult) PDSZoningPermitCounter@sdcounty.ca.gov, Borrego Springs Community Planning Group (Advisory body to PDS for Borrego Springs CDP land-use referrals), San Diego County Fire — Borrego Springs station (annexed from BSFPD 2023) (Fire-marshal review for ADU defensible space, access, water supply), Borrego Water District (Water service and connection review (in-service-area parcels))
Contractor directory (1)
Scope: city, 25 mi radius.
General Contractor (1)
- Anson Constructions
website
Utilities
- Water: Borrego Water District (in service area) or on-site well (out of service area) · 14d connect · $5,800
BWD service area covers the developed Borrego Valley village core; outlying parcels rely on private wells. The Borrego Subbasin is in the critically-overdrafted SGMA category with a 2040 sustainability target; new well permits and BWD connections face a Watermaster-managed pumping allocation framework adopted under the 2019 Groundwater Management Plan / Settlement Agreement. - Sewer: Borrego Water District (in service area) or on-site septic via San Diego County DEHQ permitting (out of service area) · 21d connect · $7,200
Most outlying parcels rely on engineered septic systems. BWD operates the village wastewater treatment plant for the core service area. - Electric: San Diego Gas & Electric (SDG&E) — Borrego Springs Microgrid (utility-scale, first in US, single transmission line + battery + solar) · 21d connect · $1,800
Borrego Springs is served by SDG&E via a single radial transmission line into the Borrego Substation, supplemented by the Borrego Springs Microgrid (2.8 MW battery + Borrego II solar) for islanded operation during transmission outages or PSPS. The microgrid is the first utility-scale microgrid in the US and a federal grant is upgrading it toward 100% clean energy.
Property values & taxes
Construction timeline
Realistic total: best 7mo · typical 11mo · worst 16mo
Lead times shorter than coastal San Diego (smaller GC pool but lower demand backlog); summer construction window is constrained by 100°F+ temperatures driving early-morning-only outdoor work May-September. Material delivery from coastal supply yards adds 1-2 days per delivery cycle.
Modular pathway inspectors are occasional with modular
Financing
State ADU loans:
Insurance impact
HOA prevalence & preemption
Borrego Springs HOA prevalence is materially lower than coastal San Diego County. Most parcels are large desert lots without HOA; the principal HOA-governed clusters are Rams Hill Country Club, Borrego Springs Resort, De Anza Country Club, and a few smaller condo/townhome developments around the village core. California AB 670 / AB 3182 preempt most HOA ADU prohibitions on single-family residential lots; HOAs retain reasonable design / aesthetic / dark-sky-compliance standards.
Regulatory overlays (4)
- wui-fire-zone
Borrego Valley sits within or immediately adjacent to State Responsibility Area; CAL FIRE FHSZ map shows Borrego Springs predominantly Moderate to High (not Very High) due to sparse desert vegetation, but the eastern ridges / canyons / Anza-Borrego SP boundary parcels carry High designation. Defensible space (PRC 4291) and CBC Chapter 7A WUI construction apply on flagged parcels. - flood-zone
FEMA SFHA along desert washes (San Felipe Creek, Borrego Sink, Coyote Creek) traverses the valley floor. Parcels along washes have Zone A or AO designation requiring elevation certificates and flood-resistant construction; many Borrego properties sit in the wash floodplain. - other
Borrego Springs Community Plan dark-sky lighting overlay (Zone E1 under County Light Pollution Code Title 5 Div 9): all new exterior lighting on residential ADUs must be full-cutoff IDA-compliant, 3000K maximum color temperature, and on motion or astronomical timer where used after midnight. This is the defining ADU-specific design overlay in Borrego Springs. - other
SGMA groundwater overlay: Borrego Subbasin is critically overdrafted; 2019 Groundwater Management Plan and adjudicated Watermaster framework allocate pumping. New ADU water demand (BWD service or new well) must conform to the basin pumping budget; this is the practical capacity ceiling on greenfield ADU development in Borrego.
Technical envelope (climate & building code)
Climate & energy code
Building code
Amendments:
- Amendment
- Amendment
- Amendment
Contractor market (aggregate)
Legal history (timeline)
Current ordinance: San Diego County Code Title 6 (Zoning Ordinance) — Accessory Dwelling Unit provisions, as amended by Ord. 10693 (2020), Ord. 10749 (2023), and the March 2026 separate-sale program, adopted 2020-08-26, last amended 2026-03-04
- 2009-08-03 — Borrego Springs Community Plan adopted as part of the San Diego County General Plan Update (city-ordinance)
The Borrego Springs Community Plan establishes the land-use, circulation, conservation, and dark-sky lighting framework for the unincorporated CDP within the County General Plan.
Effect: Defines the residential, agricultural, resort/visitor-serving and open-space designations that govern ADU siting in Borrego Springs. Includes specific dark-sky lighting standards (full-cutoff fixtures, color-temperature limits) that apply to all new exterior lighting on residential ADUs. - 2009-08-03 — San Diego County Light Pollution Code (Title 5, Div. 9 — Light Pollution) reaffirmed in CPU (county-ordinance)
County code regulating outdoor lighting in eastern unincorporated areas including Borrego Springs to protect Palomar/Anza-Borrego dark-sky observation.
Effect: Detached ADU exterior lighting in Borrego Springs (Zone B / E1 dark-sky tier) must use full-cutoff luminaires and warm color temperatures. This is the single most distinct local design constraint affecting Borrego Springs ADUs versus elsewhere in unincorporated San Diego County. - 2009-09-01 — Borrego Springs designated International Dark Sky Community by IDA (other)
Borrego Springs became the first International Dark Sky Community in California (and second in the world) following a 2007-2009 lighting survey, retrofit, and community planning effort facilitated by the Anza-Borrego Desert Natural History Association (ABDNHA).
Effect: The Dark Sky designation reinforces the County Light Pollution Code as a community-wide design expectation. ADUs are expected to use IDA-compliant fixtures even where county code minimums permit broader options. - 2020-08-26 — San Diego County Ord. No. 10693 — ADU ordinance conforming to AB 68 / AB 881 / SB 13 (county-ordinance)
Adopted by the Board of Supervisors to conform the unincorporated County's ADU ordinance to the 2019 statewide ADU reform package.
Effect: Established ministerial 60-day permit review, eliminated impact fees on ADUs under 750 sqft, removed owner-occupancy through 2024, and codified state minimum sizes. Applies in Borrego Springs. - 2023-07-07 — Borrego Springs Fire Protection District dissolved; service annexed by San Diego County Fire (other)
LAFCO-approved consolidation transferring fire/EMS service from the Borrego Springs FPD to the San Diego County Fire Authority.
Effect: Fire-marshal review for Borrego Springs ADU permits is now handled through County Fire / CAL FIRE rather than a stand-alone local FPD. Defensible-space, water-supply (cistern / 2,500 gpm), and access-road review applies as in other east-county unincorporated areas. - 2023-12-06 — San Diego County Ord. No. 10749 — ADU ordinance update for AB 2221 / SB 897 (county-ordinance)
Conformance update incorporating the 2022 statewide ADU clarifications (permit timelines, design-review limits, utility connection rules).
Effect: Tightened review-clock administration; clarified what county PDS can require during plan check. Did NOT opt into AB 1033 condo separation in this round. - 2026-03-04 — San Diego County adopts AB 1033 separate-sale ADU condo-conversion program (county-ordinance)
Board of Supervisors unanimously adopted a program permitting ADU/primary condo separation in unincorporated communities. Effective April 4, 2026.
Effect: Borrego Springs ADUs may, on new permits, be condo-mapped for independent sale separate from the primary dwelling — a policy lever materially distinct from cities that have not opted in.
Known issues (2)
- policy-review — Borrego Subbasin SGMA pumping budget constrains new water connections / well permits; some greenfield parcels cannot get new water service even though zoning would permit an ADU.
- other — PDS field inspections from Kearny Mesa add scheduling friction (90-mi one-way drive to Borrego Springs); applicants should expect inspection clusters rather than same-day rescheduling.
San Diego County — county ADU rules and overlays
County ADU ordinance
San Diego County regulates ADUs on parcels in the unincorporated county under Title 6 of the County Code (Zoning Ordinance), Sections 6156.x. The county's ADU framework layers on top of California Government Code sections 65852.2 (ADU) and 65852.22 (JADU), which preempt many local standards statewide; the county ordinance fills in the locally-controlled parameters (setbacks, design standards, parking in non-transit unincorporated areas, fire-safe design in VHFHSZ) that state law leaves to local choice. The current ordinance reflects amendments adopted 2020 (Ord. No. 10693) and 2023 (Ord. No. 10749) to conform with AB 68 / AB 881 (2019), AB 976 (2019 owner-occupancy elimination through 2024), SB 13 (2019 fee reductions), AB 2221 / SB 897 (2022 design/permit clarifications), and AB 1033 (2023 condo-ADU optional program; San Diego County has not opted into AB 1033 condo separation as of 2026-04-20). The county permits up to one ADU plus one JADU per single-family parcel by right, and the state-mandated two ADUs per multifamily lot; parking is not required on ADUs within 1/2 mile of transit. The county's distinct contributions on top of state law are the fire-hardening / defensible-space design standards for ADUs sited in Very High Fire Hazard Severity Zones, the airport-noise compatibility review for ADUs within Airport Land Use Compatibility Plan (ALUCP) zones, and the Coastal Development Permit (CDP) requirement for ADUs in the county's certified Local Coastal Program (LCP) jurisdiction.
- San Diego County Code of Regulatory Ordinances Title 6 (Zoning) — Accessory Dwelling Unit provisions
- PDS ADU Technical Bulletin and applicant handouts
- Ordinance No. 10693 — 2020 ADU ordinance conforming to AB 68 / AB 881 / SB 13
- Ordinance No. 10749 (approximate) — 2023 ADU ordinance update for AB 2221 / SB 897 / AB 1033
State-floor overlay: California state law (Gov. Code 65852.2, 65852.22) preempts most local ADU regulation. The state sets ministerial-approval requirements, caps fees, mandates 60-day permit review, forbids local owner-occupancy requirements through 2024 (extended effectively through AB 976 / subsequent amendments), sets minimum allowed sizes (850 sqft one-bedroom, 1000 sqft two-bedroom), forbids parking requirements within 1/2 mile of transit or on replacement-covered-parking ADUs, and caps impact fees at zero for ADUs under 750 sqft. San Diego County's ordinance reiterates and applies these floors, adding only the locally-controlled fire, airport, and coastal overlays. Where a project is in a VHFHSZ or coastal-commission jurisdiction, state ADU preemption still applies to the ADU allowance itself but does not preempt the county's separate fire and coastal authority over site-design standards.
County regulatory overlays
San Diego County administers or co-administers several overlay regimes that materially affect ADU siting on unincorporated parcels: (1) the California Coastal Commission's jurisdiction along the coastal zone (a narrow band up to 5 miles inland in some places), implemented through the county's certified Local Coastal Program (LCP) covering unincorporated coastal segments; (2) Very High Fire Hazard Severity Zones (VHFHSZ) designated by CAL FIRE and reviewed by the State Board of Forestry, which cover very large portions of the unincorporated back-country and drive defensible-space, ignition-resistant-construction, and access requirements; (3) FEMA Special Flood Hazard Areas (SFHA) along the San Diego River, San Dieguito River, San Luis Rey River, Otay River, Sweetwater River, Tijuana River, and associated coastal zones; and (4) Airport Land Use Compatibility Plans (ALUCP) administered by the San Diego County Regional Airport Authority's Airport Land Use Commission around MCAS Miramar (federal military), NAS North Island / Naval Outlying Landing Field Imperial Beach (federal military), Gillespie Field (Santee, county-owned), McClellan-Palomar (Carlsbad, county-owned), Brown Field (Otay Mesa, City of San Diego), Montgomery-Gibbs Executive (Kearny Mesa, City of San Diego), Ramona Airport (county-owned), Fallbrook Community Airpark (county-owned), Oceanside Municipal, and Jacumba Airport. Seismic-retrofit overlays are not a county-administered regime in San Diego (unlike parts of Los Angeles / San Francisco); California seismic building-code compliance applies statewide through the California Building Code adopted by the county.
- California Coastal Commission / County Local Coastal Program (LCP) — The county's LCP covers the unincorporated coastal segments near Del Mar Mesa, Torrey Pines extensions, Crest / Harmony Grove (tributary areas), and the Camp Pendleton / Oceanside boundary. An ADU within the coastal zone requires a Coastal Development Permit (CDP) unless categorically excluded; most single detached ADUs qualify for an Administrative CDP (noticed but ministerial-like) while those in sensitive-biological or visually-sensitive settings may require a heard CDP. The Coastal Commission retains appeal jurisdiction over county CDPs within the defined appeals area. State law (Gov. Code 65852.2(j)) preserves the CDP requirement for ADUs in the coastal zone notwithstanding the otherwise-ministerial state ADU framework.
- CAL FIRE / State Board of Forestry Very High Fire Hazard Severity Zones (VHFHSZ) and County Fire Code — Very large portions of unincorporated San Diego County — most of the East County back-country including Julian, Warner Springs, Descanso, Pine Valley, Jacumba, Campo, Boulevard, Dulzura, Potrero, Palomar Mountain, Cuyamaca, and the San Diego / Cleveland National Forest interface — are designated VHFHSZ in either the State Responsibility Area (SRA) or the county's Local Responsibility Area (LRA). An ADU in a VHFHSZ must comply with California Building Code Chapter 7A (WUI-rated exterior materials: ignition-resistant siding, dual-pane windows, 1/8-inch-max vent screens, Class A roofing, non-combustible eaves / soffits / decks), minimum 100-foot defensible-space per Pub. Res. Code 4291, minimum driveway width and turnaround per fire-district standards, and minimum fire-flow water supply (2,500 gpm residential standard, reduced for sprinklered ADUs per Sec. R313). CAL FIRE or the local FPD (Alpine, Bonita-Sunnyside, Deer Springs, Julian-Cuyamaca, Lakeside, North County, Pine Valley, Rancho Santa Fe, Rural FPD of San Diego County, Valley Center, etc.) reviews the ADU permit. The 2025 wildfire season reinforced these requirements; no county-wide moratorium has been imposed, but permit backlogs lengthen post-fire when affected areas surge rebuild applications.
- FEMA Special Flood Hazard Areas (SFHA) — National Flood Insurance Program — The county administers FEMA NFIP floodplain regulations for unincorporated parcels. Principal SFHA extents are along the San Luis Rey River (Bonsall, Pala, Pauma), San Dieguito River (Lakeside, Ramona uplands), San Diego River (Lakeside, Santee extensions), Sweetwater River (Spring Valley extensions), Otay River (Jamul, Dulzura, Otay Mesa extensions), and Tijuana River estuary (Tijuana / Imperial Beach extensions). ADUs in an SFHA require lowest-floor elevation to or above Base Flood Elevation plus 1 ft county freeboard, flood vents on enclosures below BFE, anchoring, and a post-construction Elevation Certificate. 2024-2025 saw several FEMA FIRM revision studies for Otay, San Luis Rey, and Sweetwater watersheds; owners should confirm current effective panel before design.
- Airport Land Use Compatibility Plans (ALUCP) — San Diego Regional Airport Authority ALUC — The San Diego County Regional Airport Authority serves as the ALUC for all airports in the county. ALUCP airport influence areas (AIAs) extend roughly 2-5 miles beyond each airport depending on runway configuration and establish safety zones (Zones 1-6) and noise contours (60/65/70 dB CNEL). Principal ALUCP overlays affecting unincorporated parcels are MCAS Miramar (extensive AIA covering Scripps Ranch fringes, Miramar Ranch North, Tierrasanta approaches, into unincorporated Rancho Santa Fe / Poway fringes), Gillespie Field (AIA extending into unincorporated Lakeside, El Cajon fringes, Bostonia), McClellan-Palomar (Carlsbad-adjacent unincorporated areas), Ramona Airport (large rural AIA), and Fallbrook Community Airpark (Bonsall / Fallbrook). An ADU in a safety zone may face density restrictions, CC&R / avigation-easement recording requirements, and noise-attenuation construction standards (STC-rated windows, forced-air HVAC with acoustic treatment). The ALUC reviews county-referred projects; in a safety-zone conflict the county may override only by a super-majority Board vote per PUC 21676.
- San Diego County Biological Mitigation Ordinance / Multiple Species Conservation Program (MSCP) — The county's MSCP covers south county unincorporated areas and establishes Pre-Approved Mitigation Areas and a Biological Mitigation Ordinance that triggers biological review for grading and construction in designated preserve-land overlays. An ADU outside the existing dwelling footprint that requires grading in a designated MSCP preserve or Biological Resource Core / Linkage area will trigger a biological review / mitigation obligation on top of the ministerial ADU permit. Inside a parcel's previously-disturbed building envelope the MSCP typically does not add requirements. The East County MSCP Subarea Plan remains pending final approval as of 2026-04-20.
County permitting (unincorporated parcels)
The County of San Diego Planning & Development Services (PDS) department is the single-point-of-contact for ADU permits on parcels in the unincorporated county. Unincorporated San Diego County covers approximately 3,570 square miles (about 79% of the county's 4,526 sqmi land area) and includes densely developed fringe areas (Ramona, Alpine, Lakeside, Spring Valley, Fallbrook, Valley Center), rural back-country (Julian, Warner Springs, Jacumba, Boulevard, Campo), and tribal lands (which are not county-permitted). The 18 incorporated cities (San Diego, Chula Vista, Oceanside, Escondido, Carlsbad, Vista, San Marcos, El Cajon, Santee, La Mesa, Encinitas, National City, Poway, Coronado, Imperial Beach, Lemon Grove, Del Mar, Solana Beach) permit their own ADUs independently. PDS combines planning / zoning review, building plan review, grading / drainage review, fire-district referral (most unincorporated areas are served by CAL FIRE / County Fire Authority or a local Fire Protection District rather than a city fire department), and environmental review (CEQA applicability is normally exempt for ministerial ADUs per Gov. Code 65852.2(f) and Pub. Res. Code 21080(b)(8)).
California state — ADU law and programs
State ADU law
California has the most aggressive statewide ADU preemption regime in the US, built from ~15 bills passed 2019-2025 and enforced by the Department of Housing and Community Development (HCD). The 2026 HCD ADU Handbook addendum (in effect with the 2025 Title 24 code cycle) is the operative state-level reference. The regime does four things at once: (1) preempts local zoning that would ban or unreasonably restrict ADUs; (2) imposes by-right ministerial approval with short statutory deadlines; (3) caps fees and utility-connection charges; and (4) empowers HCD to void non-compliant local ordinances.
State HOA preemption
California has the strongest statewide HOA-preemption regime in the US for accessory dwelling units, built from two bills: AB 670 (2019) voided ADU-prohibiting covenants on single-family residential lots, and AB 3182 (2020) extended and codified the preemption into the Davis-Stirling Common Interest Development Act (Civil Code §§ 4740 / 4741). The combination prohibits common-interest communities from banning ADUs, restricting rentals below 25% of separate interests, or treating ADUs as separate HOA interests. Limits remain: HOAs retain authority over reasonable design standards and statutory height limits, and the 2026 Carlsbad case (CalMatters coverage) established that an HOA's documented design-standards regime can effectively delay or constrain ADU approval short of outright prohibition.
State financing programs
California's flagship state-level ADU financing program — the CalHFA ADU Grant Program — is paused and has not been refunded since the original $100 million allocation was fully deployed 2023-12-28. The program provided up to $40,000 per qualifying homeowner for pre-construction and non-recurring closing costs and financed approximately 2,500 ADUs in two rounds. As of 2026-04, no new funding round has been announced in the state budget. CalHFA continues to publish anti-scam warnings because bad actors actively solicit homeowners claiming access to grant funds that no longer exist. State-level financing activity has shifted to local pilot programs (San Francisco, San Jose, Los Angeles, San Diego) and private financing products (Fannie Mae ADU mortgage, HELOC, construction-to-permanent).
State housing programs
California's state-level ADU programs are concentrated at HCD (technical guidance, ordinance review, enforcement) and the paused CalHFA grant pipeline (covered under stateFinancing). The state does not operate a central pre-approved ADU plan library — instead, AB 1332 (2024) created a preemption framework for local pre-approved plans with a 30-day ministerial-approval deadline, and major cities (Los Angeles, San Diego, San Jose, Sacramento, Berkeley) have rolled out their own plan catalogs. The California YIMBY coalition and other housing-policy organizations play an influential role in bill drafting; they are not state agencies but effectively drive much of the ADU legislative agenda. The Title 24 code cycle (now 2025, in effect for 2026 permits) is the authoritative building-code baseline.
Federal (United States) — ADU-relevant rules and programs
Federal ADU law
The United States has no federal statute that directly regulates accessory dwelling unit entitlement or design. Land-use authority over ADUs resides with states and local governments under the traditional police power. Federal engagement is limited to financing (Fannie/Freddie/FHA/VA/USDA), flood insurance (FEMA/NFIP), and discretionary housing programs (HUD), which are recorded in sibling sections of this file.
Federal financing programs
Federal housing-finance agencies and GSEs set nationwide underwriting rules that govern whether an ADU can be financed, appraised, and counted toward mortgage qualifying income. The relevant actors are Fannie Mae, Freddie Mac, FHA (HUD), VA, and USDA Rural Development.
Federal tax credits
There is no ADU-specific federal tax credit. ADUs may incidentally qualify for existing federal energy-efficiency and clean-energy tax credits when the ADU construction includes qualifying measures.
Federal housing programs
HUD administers several discretionary programs that can fund ADU-related activity at the grantee's election, but none is an ADU-specific program.
ZIP Code
- 92004
Post Office
- 2599 Country Club Rd, 92004