Draft 2025 Urban Water Management Plan

2025 Orange County Water Demand Projection Model

160

140

120

100

80

60

40

20

Observed

Modeled

0

Figure 3-4: Modeled vs Historical Water Use per Account for CII Use for an Agency

3.6 Irrigation Regression Development

This section reviews the development of the statistical regression model for the irrigation sector. Both potable and recycled irrigation water demands were included in the analysis.

3.6.1

Explanatory Variables and Fitted Coefficients

Explanatory variables for the final Irrigation regression equation, along with their coefficients, are reported in Table 3-6 .

Table 3-6: Irrigation Regression Variables and Coefficients

General Directional Influence

Explanatory Variable

Model Coefficient Range

Marginal Price (per 20 CCF)

-

-0.14

Normal monthly maximum temperature

+

0 to 2.58

Normal monthly maximum temperature (lagged 1 month)

+

0 to 2.34

Normal monthly precipitation

-

0 to -0.13

Normal monthly precipitation (lagged 1 month)

-

0 to -0.11

Normal monthly precipitation (lagged 2 month)

-

0 to -0.068

Agency Stage 1

-

-0.46

Agency Stage 2

-

-0.13

Agency Stage 3

-

-0.37

COVID

-0.18 to 0.26

3-13

Appendix G - 50

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