Money expended upon any unit during any fiscal year shall not exceed by more than 20 percent the amount of the estimate for that unit for that fiscal year, unless the department determines that expenditures that exceed that amount are necessary for emergency repairs or flood fighting. If in any fiscal year more money will be expended upon a unit than is, or will be, available from assessments or collections thereon derived from the maintenance area, the estimated amount of the deficit shall be added to the estimate for that unit for the following fiscal years, and if less money will be expended than collected, the estimated amount of that excess shall be deducted from the estimate.
Ca. Water Code § 12878.44