Community status, address checks, school districts and local rules, each with its source.
Alpine is an unincorporated community in San Diego County, not a city, so County government handles its permits, roads and services. It had 14,696 residents at the 2020 Census and uses ZIP Code 91901. Before you make an offer, check the exact address for fire hazard zone, flood zone, special taxes and assigned schools. More than half of Alpine is mapped Very High on CAL FIRE's State Responsibility Area map, so that check matters here.
General information only, not legal advice. See the note near the end of this page.
Want a real estate agent to look at a specific Alpine home with you? Karina Somenzari, REALTOR®, works with buyers and sellers in Alpine and across San Diego County's cities and communities, in English or Portuguese; contracts and escrow documents are in English.
| Topic | What the official record shows |
|---|---|
| Status | An unincorporated community. The Census Bureau maps it as "Alpine CDP," a census designated place. The Census Bureau describes these as closely settled, unincorporated communities that are locally recognized and identified by name. |
| Government | San Diego County says that in the unincorporated area, County government provides things a city would typically do, such as law enforcement and fire protection, roads, parks, libraries and building permits. |
| Community plan | Alpine has its own County community plan, the Alpine Community Plan, part of the County General Plan. About 97% of the community sits inside that plan area. A small part lies in the neighboring Crest-Dehesa plan area. |
| Population | 14,696 at the 2020 Census. |
| Land area | 26.786 square miles of land (Census Bureau, 2025 Gazetteer). |
| ZIP code | 91901. That ZIP Code covers Alpine and some surrounding land. |
| Law enforcement | The San Diego County Sheriff's Office serves the unincorporated area. |
| Coast | Alpine is inland. It is not in the County's Coastal Zone. |
Each check depends on the exact address. Most appear in the seller's disclosures, and you can look many of them up before you write an offer. Karina's free property report covers fire, flood and fault zones for a San Diego County address.
CAL FIRE maps Fire Hazard Severity Zones as Moderate, High or Very High. Alpine's mapped zones come from the State Responsibility Area (SRA) map. Its current version was adopted on January 31, 2024 and took effect on April 1, 2024. CAL FIRE notes that these maps measure hazard, not risk.
We sampled 150 points inside the Census boundary for Alpine against that map. About 56% fell in Very High and about 11% in High. About a third fell in no zone on the SRA map or on the 2025 local-area map, and the map does not say why. Zones can differ from one property to the next, so look up the address instead of relying on the community as a whole.
When a home in a High or Very High zone is sold, two things come with the sale:
Insurance and defensible-space work can follow from the zone, so ask about both early, ideally before your contingencies end.
Parts of Alpine are in mapped flood zones. In our sample, 1 of 150 points fell in a Special Flood Hazard Area (Zone A). A sample can't tell you about a specific lot, so look up the address at the FEMA Flood Map Service Center. If a home is in a Special Flood Hazard Area and your mortgage comes from a federally regulated, supervised or insured lender, flood insurance is required. Lenders may ask for it in other zones, so get a quote during your inspection period.
A Mello-Roos district (formally a Community Facilities District, or CFD) adds a yearly special tax to the property tax bills of owners inside its boundary. The County Auditor's FY 2025-2026 list of active Mello-Roos districts has no entry named for Alpine, Alpine Union School District or Grossmont Union High School District. It does list districts that apply only to specific areas, so never read that as "no Mello-Roos in Alpine." Check the current tax bill through the San Diego County Treasurer-Tax Collector and the seller's Mello-Roos disclosure notice. California law asks the seller to make a good-faith effort to get that notice from the agency.
Whether a home belongs to an HOA depends on the property, and this page has no Alpine HOA list. If one applies, the seller must give you the governing documents, budget and assessment information, so ask for them early and read them before your contingencies end.
Alpine Union School District runs the elementary and middle schools. Its site lists Boulder Oaks Elementary School, Shadow Hills Elementary School, Joan MacQueen Middle School, Creekside Early Learning Center and Mountain View Learning Academy. Grossmont Union High School District (GUHSD) serves high school.
District lines don't follow community boundaries. Census school-district maps put nearly all of Alpine in Alpine Union, with small edges in Dehesa Elementary and Cajon Valley Union Elementary. Check the exact address with each district.
| District | Where to look up an address |
|---|---|
| Alpine Union School District | No boundary tool found. Call the district office at 619-445-3236 (2001 Tavern Rd, Alpine, CA 91901) or see its online registration page. |
| Grossmont Union High School District | GUHSD School Locator |
| Cajon Valley Union (small part of Alpine) | Cajon Valley school site locator |
| Dehesa (small part of Alpine) | Dehesa School District |
This page doesn't rate or rank schools.
Alpine is in the unincorporated area, so County rules apply where a city would otherwise set them.
MTS Route 838, East County Square to Viejas, is the bus route with stops along Alpine Boulevard, Arnold Way and Willows Road. Its stop list includes Alpine Bl and Tavern Rd, Arnold Wy and Alpine Bl, and the eastern end at Willows Rd and Viejas Casino. The stop list also names Olde Hwy 80, Business 8 and Camino Canada, ending at East County Square. Check the MTS schedule for times, since they change.
Alpine has no trolley, COASTER or SPRINTER service. Test the drive at the hours you would actually travel before you commit to a home.
Cleveland National Forest's Descanso Ranger District has its office on Alpine Boulevard in Alpine, at 3348 Alpine Blvd. The district includes the Laguna Mountains. The Forest Service describes Mount Laguna as a large recreation area for horseback riding, mountain biking, running and hiking. Mount Laguna is not in Alpine, so check the Forest Service page for current access and conditions.
If you own in Alpine, many of the checks above are part of your disclosure package: the Natural Hazard Disclosure report, defensible-space documentation if your home is in a High or Very High zone, any HOA documents, and any Mello-Roos notice. They go along with the other forms California requires, so this isn't a complete list. The selling guide walks through disclosures, costs and timing, and you can ask for a free home value estimate.
Karina Somenzari, REALTOR®, is a real estate agent licensed in California (DRE# 02248263) with eXp Realty of California, Inc. She represents buyers and sellers in Alpine and across San Diego County. You can work with her in English or Portuguese; contracts and escrow documents are in English.
To start, tell her about your plans, call 619-369-4598 or, if you're selling, ask what your Alpine home is worth. If you'd rather talk in Portuguese, read about working with a Portuguese-speaking real estate agent.
No. Alpine is an unincorporated community in San Diego County. The Census Bureau maps it as a census designated place, which is a statistical area for a closely settled, unincorporated community. In the unincorporated area, County government provides city-type services such as law enforcement and fire protection, roads, parks, libraries and building permits. Alpine also has its own County community plan, the Alpine Community Plan.
Alpine Union School District serves elementary and middle school for nearly all of the community, and Grossmont Union High School District serves high school. Small edges of Alpine fall in neighboring elementary districts, such as Dehesa and Cajon Valley Union. Assignment depends on the exact address, so check it with each district before you rely on it.
Much of it is. On CAL FIRE's State Responsibility Area map, more than half of the community is mapped Very High and about one-ninth is mapped High. About a third was not in a zone on that map or on the 2025 local map. Zones vary by address, so check the home itself. The seller's Natural Hazard Disclosure report states the zone for the property.
The County Auditor's FY 2025-2026 list of active Mello-Roos districts shows no district named for Alpine or for its school districts. The list does include fire-related districts that apply to specific areas, so that is not a promise that a given home has none. Check the property tax bill and the seller's Mello-Roos disclosure notice.
Alpine is in the unincorporated area, so County of San Diego ADU rules apply, not a city's. Ask the County what applies to a specific lot, including fire access, septic and well questions. On March 4, 2026, the Board of Supervisors adopted a program that allows separate sale of ADUs in unincorporated communities through a condominium conversion process. Check the County's ADU page for current terms.
No. MTS Route 838, East County Square to Viejas, is the bus route with stops along Alpine Boulevard, Arnold Way and Willows Road. Check the current MTS schedule for times and stops.
Karina offers a free, no-pressure conversation in English or Portuguese, whether you're buying or selling in Alpine (contracts and escrow documents are in English). Bring an address, and she'll go over these checks with you.