Subsurface improvements shall include water distribution lines and sanitary sewer lines.
(A) Standards.
(1) Subsurface improvements shall be made to serve current and projected land use. All installations shall conform to the minimum standards therefor as established by those state and/or federal agencies having jurisdiction over the proposed installations. All installations shall also comply, to the maximum extent feasible, to such quasi-official, nationally recognized, standards as those of the American Insurance Association (formerly National Board of Fire Underwriters).
(2) Service lines to each known or assumed building location shall be installed in conjunction with the construction of the mains.
(B) Assessment formula for subsurface improvements. The assessments to be levied against properties within an area benefitted by subsurface improvements shall be distributed to those properties on the basis of trunk assessments, lateral assessments, and connection charges.
(1) Trunk sewers include lift stations, force mains and portions of the gravity collection system (oversized or overly deep) which are designed as major collectors serving larger areas. The trunk sewer assessment rate is $800 per acre. Trunk water systems include towers, hydrants, valves and oversizing necessary for adequate pressure and fire protection. The trunk water rate is $500 per acre. Trunk rates will be applied to the area benefitted, and are not normally deferred except as noted in § 94.23. Trunk rates may be revised based on current ENR indexes, assuming a July, 1975, ENR index of 2248.
(2) Lateral benefit is obtained from the branch sewer and water lines which make the utility available to the property. (If the property is adjacent to the trunk line, then both trunk and lateral benefit will be obtained from the pipe.) This rate varies from project to project depending on project geometry and costs, and is calculated by dividing the assessable lateral cost (that portion of the project cost not applicable to the trunk system as defined above) by the total number of assessment units. The assessment unit may be either adjusted frontage or a unit charge, such as "lot," "REC," or "unit."
(3) Lateral assessments will be assessed to all developed parcels adjacent to the trunk or lateral, except that where area-related unit charges are used, only that portion of the parcel within 200 feet of the trunk or lateral will receive lateral assessments. In developed or platted areas deferments will normally not be given.
(4) In undeveloped unplatted areas, lateral assessments for parcels adjacent to trunk or lateral utilities may be deferred until development by establishing a special connection charge within a defined district, such charge to be paid at the time of development or connection. Further, development of the lateral system within the trunk area will be assessed as separate projects unless installed by the developer, in which case no added lateral assessment will be made. Only one trunk assessment will be made.
(5) If the improvement is accomplished under the subdivision regulations of the city, applicable "trunk charges" shall be assessable against properties within the subdivision. All utility costs shall be the developer's, with the following exceptions:
(a) On water main or sanitary sewer construction within a subdivision, if the size of mains installed is larger than the size of mains required to provide complete water service (including fire-fighting potential as recommended by nationally recognized standards) or sewer service to the subdivision, the costs for oversizing such mains shall be regarded as "city cost."
(b) On water main or sanitary sewer construction where no point of connection to existing mains is available within, or at the outside boundary of the subdivision, the city may levy normal assessments to all intervening properties benefitted by the required extensions and use the assessments collected to defray the project costs relating to the intervening properties. Where such extension beyond
the subdivision boundary is installed and oversized to provide future service to the areas other than the subdivision, the costs for such extension shall be equitably distributed between the areas to be served.
('69 Code, § 2.21, Subd. 3 B.)