(a) To determine the amount of assessment for each assessment account, computations will be made by adding together a base charge as specified in the commission order adopted in accordance with §304.61 of this title (relating to Costs of Administration) and, as applicable, either or both of the following:
  (1) a user fee, which is the mathematical product of the total assessment account and the appropriate assessment rate as determined by §304.62 of this title (relating to Determination of Assessment Rates); provided, however, that if the water right authorizes more than one type of use, and if the maximum amount of water authorized to be used annually for all uses (the maximum total authorization) is less than the sum of the maximum amounts authorized to be used annually for each use (the sum of all authorizations), then, in calculating the fee for each account the number to be used for the authorized amount must be the product of the maximum total authorization and a fraction whose numerator is the amount of water authorized for that use, and whose denominator is the sum of all authorizations; and also provided that the water right holder or the executive director may apply to the commission for, and the commission may grant, an order providing, for assessment purposes only, that different portions of the total amount of water authorized be applied to the various authorized uses; and
  (2) a storage fee for on-channel storage, which is calculated by multiplying the total amount of water authorized for conservation storage under that assessment account by the storage assessment rate as determined by §304.62 of this title. For any water right authorizing storage and more than one type of use for the same owner, the storage fee for that owner's total storage authorization must be applied to the assessment account for any one of the uses associated with that owner.
(b) The assessment must be paid to the executive director in advance of expenditures. The executive director shall specify the dates by which payments will be due, and may provide for payments in installments. Penalties and interest for the late payment of fees will be assessed in accordance with Chapter 12 of this title (relating to Payment of Fees). If fees are paid in installments, penalties and interest for late payment will be computed on the amount of the installment due. The executive director shall transmit all collections to the state treasurer to be held in a special fund to provide for the cost of the watermaster operation.
(c) Water may not be diverted, taken, stored, transported, or used by any diverter or agent while any assessment payment is delinquent.
(d) Either the water right owner or agent shall pay the assessment, but only one person per assessment account shall be authorized to pay assessments.

Source Note: The provisions of this §304.63 adopted to be effective August 5, 1988, 13 TexReg 3639; amended to be effective February 14, 1997, 22 TexReg 1325; amended to be effective May 3, 2006, 31 TexReg 3578