(A) Recalculation of charges. If a property owner or person responsible for paying the storm water drainage charge questions the correctness of such a charge, that person may have the determination of the charge recomputed by written request to the Director of Public Works. This request shall be made within 30 days of the mailing of the billing in question.
(B) Adjustments or credits to the storm water drainage charges.
(1) Rate structure; purpose of adjustments.
(a) The municipal storm water drainage utility uses a rate structure based on the anticipated relative contribution of storm water drainage runoff volume and pollutant loading to the storm water drainage system. A parcel’s contribution is determined by that parcel’s size and its land use, under the principle that more intensively developed land uses typically have a larger percentage of impervious surface and contribute a much greater volume of water to the system for the standard rainfall event of 2.3 inches in 24 hours and larger pollutant loading.
(b) It is recognized that some parcels, due either to their unique topographic, vegetative, geologic and other characteristics have a hydrologic response substantially different from that of similarly sized parcels of the same land use. To provide for an equitable assessment of storm water drainage charges, based on reasonably expected contribution of flows, provisions need to be made to permit adjustments to the storm water drainage charge for those parcels with unique or unusual characteristics, or credits to the storm water drainage charge for those parcels with storm water runoff volume and/or quality treatment facilities.
(2) Grounds for adjustment.
(a) The basis of the city’s storm water drainage charges is the anticipated relative contribution of storm water runoff volume and pollutant loading to the storm water drainage system from a given parcel. Where unique or unusual conditions exist where the actual contributions of storm water runoff volume or pollutant loading from a given parcel are substantially different from those anticipated by the storm water drainage rate structure, the Director of Public Works, or designee thereof, may adjust or credit the storm water drainage charge for the parcel to an appropriate level in accordance with the guidelines specified herein.
(b) The subchapter establishing the storm water drainage utility provides for the Director of Public Works to make adjustments or credits to the charges when:
1. The property owner supplies data demonstrating a storm water runoff volume for the standard rainfall event substantially different from that being used for the parcel; or
2. The property owner supplies data demonstrating that storm water runoff from the parcel is being treated to provide the required removal efficiency for total suspended solids (TSS).
(3) Property owner to provide detailed information. It is the responsibility of the property owner or agent thereof to present to the Director of Public Works, or designee thereof, sufficient information concerning a parcel’s hydrologic characteristics to permit an accurate assessment of the conditions that exist.
(a) This information may include, but is not limited to:
1. Site plan showing locations of all buildings, paved areas and other development relative to lot lines;
2. The total lot area and area of impervious surfaces, in square feet;
3. Site topography or contours of sufficient detail to ascertain flow directions, rates and volumes;
4. Hydraulic calculations specifying outflow volumes and rates for various rainfall events; and
5. Calculation of total suspended solids removal efficient of any on-site storm water runoff treatment facility.
(b) Failure to provide this information within 30 days after delivery of a written request shall result in the assignment of the highest classification level for volume, quality and utility REF.
(4) Adjustments where parcel runoff is significantly different from land use standard. Where the unit runoff generated by a parcel differs from the assigned amount for that land use category by more than 20%, the Director of Public Works, or designee thereof, may adjust the parcel’s storm water drainage charge in accordance with the following procedure.
(a) Calculation of unit runoff for the parcel shall be determined by the methods outlined in the Natural Resources Conservation Service Technical Release No. 55, utilizing a one-year event of 24-hour duration as the standard rainfall event.
(b) If the calculated unit runoff is shown to differ from the assigned amount for that land use category by 20% or more, the volume portion of the fee for that parcel shall be adjusted by multiplying it by the ratio of the calculated unit runoff to the standard unit runoff.
(c) A parcel’s storm water drainage charge shall be subject to increases as well as decreases by this procedure.
(d) For parcels with ponds covered by public easements, the area used for the calculation of the charge shall be reduced by the size of the easement area.
(e) Because single-family and duplex fees are not based upon actual parcel acreage, no adjustments for unit runoff differences will be made for those land uses, except for totally vacant, unimproved, fully turfed parcels.
(f) Adjustments shall not be retroactive. They become effective from the date they are approved.
(5) Procedures for calculation of storm water credits. Procedures for calculation of storm water detention credits for volume charges and for calculation of water quality treatment credits for quality charges shall be based on standards prepared by the Director of Public Works and approved by the City Council.
(6) City’s right to inspect facilities and initiate fee adjustments and/or credits.
(a) The Director of Public Works, or designee thereof, reserves the right to inspect periodically all storm drainage control facilities to ascertain that they are operating properly. If such a system, due to improper maintenance or other reason, fails to detain or cleanse storm water runoff in an effective manner, the Director of Public Works, or designee thereof, may eliminate or reduce detention or water quality credits to an appropriate level. The facility shall not be eligible to apply for storm drainage charge adjustments and/or credits for a period of 12 months following any adjustment and/or credit. Adjustments and credits shall not be made retroactively. An appeal from the Director of Public Works’ determination may be made to the City Council.
(b) The issuance of any building permit or other action that changes or intensifies an existing land use shall be cause for an adjustment of storm water drainage charges to an appropriate level.
(2004 Code, § 53.129) (Ord. 01-289, passed 1-23-2001)