Urban Water Use Objective = Sum of Standards

Water providers cannot exceed the total of the following components:

1. Indoor Residential Water Budget

• Standard (GPCD – gallons per capita daily):

• 55 GPCD until Jan 1, 2025
• 47 GPCD from Jan 1, 2025 – Jan 1, 2030
• 42 GPCD beginning Jan 1, 2030

• Multiplied by: Service area population × 365 days

2. Outdoor Residential Water Budget

Formula: Landscape Efficiency Factor × Net ETo × Landscape Area × 0.62

• Landscape Efficiency Factor (varies by year):

• 0.80 until June 30, 2028
• 0.63 from July 1, 2028 – June 30, 2035
• 0.55 beginning July 1, 2035 (0.45 for new construction starting 2024)

• Net ETo: Estimated evapotranspiration (water used by plants minus rainfall)

• Landscape Area: Irrigated square footage

• Conversion Factor: 0.62 (converts water depth to gallons)

3. CII Landscapes with Dedicated Irrigation Meters (DIM)

• Uses the same formula as Outdoor Residential Standard

• Efficiency Factors:

• 0.80 until June 30, 2028
• 0.63 until June 30, 2035
• 0.45 beginning July 1, 2035 (and for new construction in 2024)

4. Water Loss Budget

• Based on regulatory requirements in SB 555 (2015).

• Accounts for real system water losses.

5. Adjustments (If Applicable)

• Variances

• Temporary provisions

• Bonus incentives

Notes

• Agriculture and indoor CII are not part of the Urban Water Use Objective, though indoor CII is managed separately by performance measures.

✅ Final Urban Water Use Objective = Indoor Residential Budget + Outdoor Residential Budget + CII-DIM Outdoor Budget + Water Loss Budget + (Adjustments, if any)

For more information about the Water Use Objective Exploration Tool, visit the State Water Resources Control Board website: https://www.waterboards.ca.gov/conservation/water-use-explorer/