15-1-8: METHODOLOGY FOR THE CALCULATION OF IMPACT FEES:
   A.   General Provisions:
      1.   Accounting Principles: The calculation of the impact fee shall be in accordance with generally accepted accounting principles. A development impact fee shall not be deemed invalid because payment of the fee may result in an incidental benefit to owners or developers within the service area other than the fee payer.
      2.   Levels Of Service: The impact fee shall be calculated on the basis of levels of service for public facilities in the adopted capital improvement plan that are applicable to existing development as well as new growth and development. The construction, improvement, expansion or enlargement of new or existing public facilities for which the impact fee is imposed must be attributable to the capacity demands generated by the new development.
   B.   Methodology; Proportionate Methodology: The impact fee shall not exceed a proportionate share of the cost of the system improvements determined in accordance with Idaho Code § 67-8207, as it may be amended. Impact fees shall be based on actual system improvements costs or reasonable estimates of such costs. The amount of the impact fee shall be calculated using the methodology contained in the adopted capital improvements plan.
   C.   Proportionate Share Determination:
      1.   The impact fee shall be based on a reasonable and fair formula or method under which the impact fee imposed does not exceed a proportionate share of the costs incurred or to be incurred by the county in the provision of system improvements to serve the new development. The proportionate share is the costs attributable to the new development after the county considers the following:
         a.   Any appropriate credit, offset or contribution of money, dedication of land or construction of system improvements;
         b.   Payments reasonably anticipated to be made by or as a result of a new Development in the form of user fees and debt service payments;
         c.   That portion of general tax or other revenues allocated by the county to system improvements; and
         d.   All other available sources of funding such system improvements.
      2.   In determining the proportionate share of the cost of system improvements to be paid by the developer, the following factors shall be considered by the county and accounted for in the calculation of the impact fee:
         a.   The costs of existing system improvements within the service area;
         b.   The means by which existing system improvements have been financed;
         c.   The extent to which the new development will contribute to system improvements costs through taxation, assessments, or developer or landowner contributions, or has previously contributed to system improvements costs through developer or landowner contributions;
         d.   The extent to which the new development is required to contribute to the cost of existing system improvements in the future;
         e.   The extent to which the new development should be credited for providing system improvements, without charge to other properties within the service area;
         f.   Extraordinary costs, if any, incurred in serving the new development;
         g.   The time and price differential inherent in a fair comparison of fees paid at different times; and
         h.   The availability of other sources of funding system improvements including, but not limited to, user charges, general tax levies, intergovernmental transfers and special taxation. (Ord. 2021-10, -23-2021)