13.20.250   System improvement design.
   A.   Purpose and general requirements.
      1.   This section provides requirements for the design of a system improvement. These requirements are intended to protect public health and welfare as well as the environment. They also ensure adequate County access for operation, maintenance, and repair of the PSCS.
      2.   The Department has absolute discretion to determine whether all or part of a developer proposed sewerage system will become part of the PSCS.
      3.   The Department may require an applicant to provide a system improvement for capacity and flow-through service for future connecting developments. The Department may also require an applicant to augment the downstream PSCS in order to provide capacity for the applicant's development and future connecting developments.
      4.   A system improvement required for service to the area under development will be provided at the sole expense of the applicant.
      5.   As a condition of approval, off-site easements recorded by separate instrument must be identified on the final sealed SIP by the docket and page or sequence number.
      6.   An approved SIP is valid for the term of the ADEQ construction authorization, or two (2) years from date of approval, whichever is later.
   B.   Final plats, easements, and rights of way.
      1.   Prior to recording the system improvement easements, the County will review and accept final subdivision plats or final easements descriptions by separate instrument. Documents will delineate easements or rights of way for the proposed PSCS.
      2.   Easements and rights of way will conform to those shown in the SIP.
   C.   Wastewater service agreements.
      1.   The Department may require an applicant to enter into a WSA. The WSA will fully document any additional construction requirements, compensation commitments, or other unique considerations.
      2.   An applicant's failure to fully comply with the terms and conditions of the WSA will render void any County Type III Response or commitment to provide wastewater service to future connections within the area under development.
      3.   Reimbursement - wastewater utility fee credit. The County may enter into a WSA with an applicant for credit to cover the incremental cost of a system improvement incurred for a department-required augmentation (over-sizing or deepening) beyond the size/depth required to serve the area under development or for a department-required extension of the system improvement for purposes of providing service for future development.
         a.   The incremental construction cost for over-sizing is the difference in eligible construction costs and engineering fees between the base pipe size designed to serve the area under development and the system improvement size actually constructed at the direction of the Department. The Department will determine the required over-sized system improvement. Eligible construction costs and engineering fees for oversizing-related incremental construction costs do not include reimbursement for those items listed in § 109-5.03, Non-Allowable Charges, of the Pima Association of Governments issued "Standard Specifications and Detail for Public Improvements" as it may, from time to time, be amended.
         b.   The incremental construction cost for deepening of the sewer is the difference in eligible construction costs and engineering fees between the design depth required to serve the area under development and the system improvement depth actually constructed at the direction of the Department. The Department will determine the required system improvement depth.
         c.   For flow-through extensions, the credit value will be determined based on eligible construction costs and engineering fees for the required length of extension. The Department will determine the required extension system improvement to provide flow-through.
         d.   The value of credit will be calculated using the Department's schedule of values.
         e.   In the event applicant can demonstrate, in a form and manner acceptable to the Department, that the schedule of values undervalues the actual, reasonable aggregate cost of the constructed over-sized system improvement by twenty-five (25) percent or more, the Department will allow the use of actual construction costs to calculate a credit value.
         f.   Credits will only be applied as an offset to the wastewater utility fee. Under no circumstances will the County issue cash refunds for credits.
         g.   The credits will be valid for ten (10) years from the execution of the WSA by the BOS.
         h.   A credit is assignable.
         i.   The value of credits applied to offset the wastewater utility fee for connections within an area under development cannot exceed the total wastewater utility fee, less applicable discounts, to be collected from that area under development.
      4.   Discount for qualifying system improvement. The County may enter into a WSA with an applicant to provide a mechanism for discounting the wastewater utility fee for the construction of a qualifying system improvement.
         a.   For residential areas under development, one dwelling within the area under development will qualify for wastewater utility fee discount status for each twenty-five (25) feet of qualifying system improvement constructed. See § 13.20.600 for discounts.
         b.   For commercial/industrial/multi-family areas under development, one unit will qualify for a discount for each twenty-five (25) feet of qualifying system improvement constructed. See § 13.20.600 for discounts.
         c.   The qualifying system improvement must have a minimum length of twenty-five (25) feet and is measured from the point of connection to the PSCS to the closest edge of the area under development for any dwelling units or commercial/industrial/multi-family projects to be awarded the discount.
         d.   Discounts are assigned to an area under development.
         e.   Discounts cannot be transferred outside of the area under development and do not expire.
         f.   The value of the awarded discount cannot exceed the total wastewater utility fee to be collected from the unit or area under development as set forth in § 13.20.400.
         g.   Discounts may be used in conjunction with credits.
      5.   Special facility.
         a.   A special facility must meet all engineering design standards, department specifications for unique components, and operational requirements of the Department.
         b.   A wastewater service agreement may be required to address unique circumstances of the special facility transfer or operation.
(Ord. 2019-20 § 1 (part), 2019)