§ 154.120  STORMWATER MANAGEMENT.
   (A)   (1)   All developments and earth changes subject to review under the requirements of this chapter shall be designed, constructed, and maintained to prevent flooding and protect water quality. The particular facilities and measures required on-site shall reflect the natural features, wetlands, and watercourses on the site; the potential for on-site and off-site flooding, water pollution, and erosion; and the size of the site.
      (2)   Where it is determined that the public storm drainage system lacks sufficient capacity to control drainage to off-site properties and drainageways, the city may require on-site detention storage of stormwater in accordance with the standards of the city and County Drain Commission.
   (B)   Stormwater management shall comply with the following standards.
      (1)   The design of storm sewers, detention facilities, and other stormwater management facilities shall comply with the standards of the County Drain Commission or the city design standards, whichever is more restrictive.
      (2)   Stormwater management conveyance, storage, and infiltration measures and facilities shall be designed to prevent flood hazards and water pollution related to stormwater runoff and soil erosion from the proposed development.
      (3)   The use of swales and vegetated buffer strips is encouraged in cases where it is safe as a method of stormwater conveyance so as to decrease runoff velocity, allow for natural infiltration, allow suspended sediment particles to settle, and to remove pollutants.
      (4)   Alterations to natural drainage patterns shall not create flooding or water pollution for adjacent or downstream property owners.
      (5)   Discharge of runoff from any site, which may contain oil, grease, toxic chemicals, or other polluting materials is prohibited. If a property owner desires to propose measures to reduce and trap pollutants, the owner must meet the requirements of the State Department of Environmental Quality and the County Drain Commissioner, based upon professionally accepted principles, such a proposal shall be submitted and reviewed by the City Engineer, with consultation of appropriate experts.
      (6)   Drainage systems shall be designed to protect public health and safety and to be visually attractive, taking into consideration viable alternatives.
      (7)   Maintenance of detention basins shall be the responsibility of the property owner.
(Ord. 285, passed 12-8-2003)  Penalty, see § 154.999