Landscape Irrigation Rates

The following at-a-glance rates are for customers who have a dedicated landscape irrigation meter. Complete water rate information is available in the IRWD Rates and Charges document. Since the water budget changes weekly, the most effective way to avoid overuse charges is to monitor the usage weekly (using the meter/water budget log sheet) and compare it to the weekly water budget.

Budget information can also be found at ET Hotline, updated on Monday mornings:

English:  (949) 453-5451
Spanish: (949) 453-5452

If you have any questions, or need to discuss your landscape irrigation account, please call (949) 453-5581 or email


 Water Budget Formula

ET x Kc x 1.25 x LA = landscape potable water budget in acre-inches.
ET x Kc x 1.33 x LA = landscape recycled water budget in acre-inches.

To convert CCF, multiply by 36.3. CCF stands for "hundred cubic feet." One CCF equals approximately 748 gallons.

The four factors used to determine a budget for a particular landscape area:

  1. ET (evapotranspiration) - from IRWD weather stations located in coastal, central or foothill zones.

  2. Kc (crop coefficient) - is the relative amount of water drought tolerant plans need at various times of the year. A crop co-efficient of 0.6 for drought tolerant landscapes is applied for potable irrigation, and a crop-coefficient averaging 0.65 for warm-season turf if applied to recycled water irrigation.

  3. 1.25 or 1.33 irrigation system effieciency - extra water to make up for inefficiencies in the irrigation system. An irrigation efficiency of 80% is applied to potable water and 75% to recycled water. In the formula this is calculated as = 1/0.80 = 1.25 applied to potable customers and 1/0.75 = 1.33 applied to recycled water. No irrigation system is 100 percent efficient, IRWD assumes a 80 percent efficiency level and budgets extra water through this formula to account for inefficiencies in your irrigation system.

  4. LA  = landscape acreage

 Irvine Rate Area Landscape Irrigation Water Rates


Rate (per ccf*)              

Use (Percent of Allocation)  

Low Volume

$1.47 potable
$1.19 recycled

0 - 40%
0 - 40%

Base Rate

$2.00 potable
$1.57 recycled

41% - 100%
41% - 100%


$4.86 potable
$3.15 recycled

101% - 160%
101% - 140%


$13.63 potable
$6.62 recycled