Ordinance No. 2025-521 – An Ordinance to Amend the Municipal Code of Tiffin, Iowa, Chapter 160, Flood Plain Management

on-site systems) shall be provided with a level of flood protection equal to or greater than one foot above the base flood elevation. (3) New or replacement water supply systems shall be designed to minimize or eliminate infiltration of flood waters into the system. Water supply treatment facilities (other than on-site systems) shall be provided with a level of protection equal to or greater than one foot above the base flood elevation. (4) Utilities such as gas or electrical systems shall be located and constructed to minimize or eliminate flood damage to the system and the risk associated with such flood damaged or impaired systems. G. Storage of Equipment and Materials. Storage of equipment and materials that are flammable, explosive, or injurious to human, animal, or plant life is prohibited unless elevated a minimum of one foot above the base flood elevation. Other material and equipment must either be similarly elevated or: (1) Not subject to major flood damage and anchored to prevent movement due to flood waters; or (2) Readily removable from the area within the time available after flood warning. H. Flood Control Structures. Flood control structural works such as levees, flood walls, etc. shall provide, at a minimum, protection from the base flood with a minimum of three feet of design freeboard and shall provide for adequate interior drainage. In addition, the Department of Natural Resources shall approve structural flood control works. I. Watercourse Alterations. Watercourse alterations or relocations must be designed to maintain the flood carrying capacity within the altered or relocated portion. In addition, the Department of Natural Resources must approve such alterations or relocations. J. Subdivision. Subdivisions (including factory-built home parks and subdivisions) shall be consistent with the need to minimize flood damages and shall have adequate drainage provided to reduce exposure to flood damage. Development associated with subdivision proposals (including the installation of public utilities) shall meet the applicable performance standards of this chapter. Subdivision proposals intended for residential use shall provide all lots with a means of access which will be passable by wheeled vehicles during the base flood. Proposals for subdivisions greater than five acres or 50 lots (whichever is less) shall include base flood elevation data for those areas located within the Special Flood Hazard Area. K. Accessory Structures to Residential Uses. (1) Detached garages, sheds, and similar structures that are incidental to a residential use are not exempt from the base flood elevation requirements. L. Recreational Vehicles. Recreational vehicles are exempt from the requirements of Section 160.05(E) regarding anchoring and elevation of factory-built homes when the following criteria are satisfied. (1) The recreational vehicle shall be located on the site for less than 180 consecutive days; and (2) The recreational vehicle must be fully licensed and ready for highway use. A recreational vehicle is ready for highway use if it is on its wheels or jacking system and is attached to the site only by quick disconnect type utilities and security devices and has no permanently attached additions. Recreational vehicles that are located on the site for more than 180 consecutive days or are not ready for highway use must satisfy requirements of Section 160.05(E) regarding anchoring and elevation of factory-built homes. M. Pipeline Crossings. Pipeline river and stream crossings shall be buried in the streambed and banks, or otherwise sufficiently protected to prevent rupture due to channel degradation and meandering.