Base Index Calculation
CII water allocations (base indices) are determined from actual historical water usage for each individual customer. The monthly water bill is calculated by comparing actual usage with the base index. Consumption at or below the base index is charged at 91 cents per 100 cubic feet (ccf) of water. Consumption that exceeds the base index is charged at incrementally higher rates to encourage efficient water use.

Base Index Changes
When a business grows, water needs may grow as well. Adding more employees, increasing manufacturing output, and serving more customers may push water consumption above the historical base allocation. If this happens, inefficient, excessive, or wasteful penalty charges will appear on the water bill. This indicates that the base index may need to be adjusted to meet new water needs. IRWD will re-evaluate a customer's base index upon request. Call the IRWD Conservation Office at (949) 453-5542.

Bill Adjustment Requests
Customers who have received a base index adjustment may also receive a bill adjustment to offset water bill penalties recevied as the result of an insufficient allocation. Also, in certain one-time "special water use" circumstances, such as the flushing and refilling of a pool or water tank, a bill adjustment may be requested to offset one-time penalties.

Leaks
Bill adjustments are also available for CII customers who have identified and corrected leaks leading to penalties. To receive a leak-related water bill adjustment, customers must provide plumbing receipts for the leak repair, and the following month's water bill must show that water use has returned to a non-penalty (ie., Base Rate) level.