Glendora, California Zoning Map

The Arrow Highway Specific Plan creates a distinct regulatory environment along the corridor with sub-districts spanning buffer residential, medium and high-density residential, commercial, industrial, and several mixed-use designations. High-density residential (AHSP-C-HR at 29.18 acres) and the commercial core mixed-use (AHSP-MU-CC at 13.67 acres) allow housing types and intensities not permitted in the surrounding estate zones. Developers pursuing this corridor should review the specific plan's design standards alongside the base building controls.

Glendora's estate zoning is unusually dominant - four Estate zones (E-4 through E-7) alone cover more than 2,920 acres, and the E-7 zone at 1,402 acres is the single largest residential district in the city. This pattern reflects the city's hillside and foothill geography and a longstanding planning philosophy favoring low-density single-family uses in the northern portions of the city. The practical effect for developers is that large-lot subdivision opportunities are limited, and intensification is largely confined to the Arrow Highway and Civic Center specific plan areas.

The Garden Apartment (GA) zone at 76.39 acres is the main location for traditional multifamily development, supplemented by the Arrow Highway Specific Plan's high-density residential sub-district (AHSP-C-HR, 29.18 acres) and the Planned Redevelopment (PR, 75.57 acres) zone. The Limited Garden Apartment (LGA) zone at 4.98 acres offers a smaller, more constrained multifamily opportunity. State density bonus law can also increase allowable units on qualifying sites citywide.

The Open Space Natural (OSN) district at 3,978.01 acres covers most of Glendora's hillside and canyon land, effectively restricting development to conservation or very limited uses. Estate zones (E-5, E-6, E-7) that border the open space area carry large minimum lot sizes consistent with hillside development standards, including the full suite of building controls covering FAR, coverage, setbacks, and height. Due diligence on hillside parcels must also address slope stability, wildfire hazard, and access road requirements under both local and state law.

SB-9 allows ministerial approval of lot splits and duplexes on single-family parcels statewide, which applies to Glendora's extensive estate zones. However, lots in high-fire hazard severity zones or with significant slope may face state-law exclusions that limit SB-9 eligibility. Given Glendora's foothill geography and the scale of its E-5 through E-7 zones, SB-9 feasibility must be evaluated parcel-by-parcel using hazard zone mapping and local objective standards.