A Resident's Guide to Castro Valley's Local Ordinances

Castro Valley, California may not be the biggest city in the state, but it has its own set of local rules that residents need to follow. With 30 tracked ordinances across 16 categories, there is more here than you might expect.

Accessory Structures

ADU Rules: Alameda County's ADU ordinance follows California state law (Gov. Code §65852.2) - one ADU and one JADU are ministerially permitted on any single-family lot in Castro Valley.

Also covered: Garage Conversions (moderate). See the full accessory structures guide for Castro Valley for details.

Animal Ordinances

Exotic Pets: Castro Valley follows California Fish & Game Code §2118 - keeping wild or exotic animals (large reptiles, primates, big cats, ferrets, hedgehogs in CA, etc.) is prohibited without a state permit, plus Alameda County's animal-fanciers permit covers other non-standard pets..

Also covered: Chickens & Livestock (moderate), Dog Leash Laws (moderate). See the full animal ordinances guide for Castro Valley for details.

Landscaping Rules

Water Restrictions: Castro Valley is served by East Bay Municipal Utility District (EBMUD). EBMUD's Water Conservation Regulation 14 permanently bans irrigation runoff, hosing down hardscape, and using non-recirculating water features.

Also covered: Tree Trimming (moderate). See the full landscaping rules guide for Castro Valley for details.

Swimming Pools & Spas

Safety Rules: Public and semi-public pools in Castro Valley (HOAs, apartments) must meet Alameda County Department of Environmental Health permitting under CCR Title 22 Group 8 - daily chemical testing, anti-entrapment drain covers (VGB Act), and posted safety rules..

Environmental Rules

Stormwater Management: Castro Valley is in the Alameda Countywide Clean Water Program (ACCWP) NPDES permit area. Only rain goes in the storm drain - no washing pollutants, sediment, soaps, or yard waste into gutters..

Also covered: Flood Zones (moderate). See the full environmental rules guide for Castro Valley for details.

Curfew Laws

Juvenile Curfew: Alameda County Code Chapter 6.48 imposes a youth curfew: minors under 18 may not be in any public place or on public premises in unincorporated areas (including Castro Valley) between 11 p.m. and 5 a.m.

Noise Ordinances

Quiet Hours: Castro Valley is unincorporated and operates under Alameda County Code Chapter 6.60 (Noise). §6.60.050 makes it a violation to operate any sound-producing device at any hour if the sound is 'plainly audible at a distance of 50 feet,' with stricter weekday/weekend hour windows for tools and vehicle work..

Also covered: Leaf Blower Rules (moderate), Barking Dogs (moderate), Construction Hours (moderate). See the full noise ordinances guide for Castro Valley for details.

Short-Term Rentals

Occupancy Limits: Castro Valley STRs have no dedicated occupancy cap, but the unit must comply with California Building Code occupancy standards and Alameda County zoning use limits for the underlying single-family or multi-family district..

Also covered: Permit Requirements (moderate). See the full short-term rentals guide for Castro Valley for details.

Parking Rules

Street Parking Limits: Castro Valley follows California Vehicle Code §22651 plus Alameda County parking rules. There is a 72-hour parking limit on any street; no overnight RV/oversize vehicle parking on most residential streets without a permit..

Also covered: Commercial Vehicle Restrictions (moderate), RV & Boat Parking (moderate). See the full parking rules guide for Castro Valley for details.

Fire Regulations

Smoke Detectors: California Health & Safety Code §§13113.7 and 13260 require working smoke alarms in every bedroom, outside each sleeping area, and on each floor of a Castro Valley dwelling, plus CO alarms in any home with fuel appliances or an attached garage..

Also covered: Brush Clearance (strict). See the full fire regulations guide for Castro Valley for details.

Fence Regulations

Height Limits: Alameda County Code §17.52.430 limits residential fences in Castro Valley to 4 feet in the required front yard, 6 feet in side and rear yards, and 2 feet within 30 feet of a street intersection (visibility triangle)..

Also covered: Neighbor Fence Rules (permissive). See the full fence regulations guide for Castro Valley for details.

Home Business

Signage Rules: Castro Valley home businesses may not have any exterior signage in residential districts beyond a small (typically 1 sq ft) name/address plate per Alameda County Code §17.52.520. No illuminated, projecting or off-premises signs are allowed..

Tree Protection

Protected Tree Species: Standard Castro Valley parcels have no general private-property tree protection ordinance. Only street trees in the County right-of-way (PWA Tree Ordinance) and the Fairview view-ordinance Ch.

Outdoor Lighting

Light Pollution & Sky Glow: Alameda County zoning requires outdoor lighting to be shielded and directed downward to minimize glare onto neighboring properties. Light trespass is treated as a Ch.

Food Trucks & Mobile Vendors

Food Truck Permits: Mobile food vendors in Castro Valley need a Mobile Food Facility Permit from Alameda County Department of Environmental Health plus a County Business License. Operations on private property need landowner consent and zoning compatibility..

Soliciting & Door-to-Door

Solicitor Permits: Alameda County does not require a peddler/solicitor permit specifically, but commercial door-to-door sellers must obtain a county business license under Ch. 3.04 and respect 'No Soliciting' signs..

What to Do With This Information

Think of this as a map of the regulatory landscape in Castro Valley. For any rule that directly affects a decision you are making, click through to the full ordinance page for penalty details and exceptions, and confirm with the city if the stakes are high.