Water Restrictions: Ontario vs Rialto
How do water restrictions rules compare between Ontario, CA and Rialto, CA?
Ontario and Rialto have similar restriction levels.
Ontario, CA
San Bernardino County
Ontario's Water Shortage Contingency Plan limits outdoor watering to assigned days and cool hours. AB 1572 bans potable water on non-functional turf at commercial and HOA sites starting January 2027.
View full Ontario rules →Rialto, CA
San Bernardino County
Rialto Water Services enforces year-round CA prohibited-use rules and assigned watering days. Under State Water Board Emergency Regulations and city policy, outdoor irrigation is limited to designated days, no runoff, no hose-down of hardscape, and no watering within 48 hours of rain.
View full Rialto rules →Key Facts Comparison
| Fact | Ontario | Rialto |
|---|---|---|
| Authority | Ontario WSCP and CA Water Code | - |
| Overspray | Prohibited at all times | - |
| Drought watering | Assigned days, early or late | - |
| AB 1572 | Bans non-functional turf irrigation | - |
| AB 1572 start | January 1, 2027 (commercial) | - |
| Hose-Down Hardscape | - | Prohibited statewide |
| Runoff to Street | - | Prohibited |
| Water After Rain | - | No watering within 48 hrs |
| MWELO Threshold | - | New landscapes ≥500 sq ft |
Highlighted rows indicate differences between cities.
Ontario FAQ
What days can I water my Ontario lawn?
During drought stages the city assigns watering days, typically limiting homes to two or three days per week and only before 9 a.m. or after 6 p.m. to prevent evaporation.
Does AB 1572 force me to rip out my home lawn?
No. AB 1572 applies to non-functional turf at commercial, industrial, institutional, and HOA common areas. Single-family front and back lawns are exempt from the state ban.
Rialto FAQ
What days can I water my lawn in Rialto?
Rialto Water Services publishes assigned watering days that change with drought stage (commonly 3 days/week, before 8 AM or after 6 PM). Check rialtowater.com for the current schedule.
Can I wash my car at home?
Yes, but only with a hose equipped with a positive shut-off nozzle, and runoff cannot flow into the street. Washing on dirt/lawn or at a commercial recycled-water car wash is preferred.
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