A. Findings. The city council of the City of Columbus finds that:
1. Excessive quantities of soil may erode from areas undergoing development for certain non-agricultural uses including but not limited to the construction of dwelling units, commercial buildings, and industrial plants, the building of roads and streets, and the creation of recreational facilities;
2. Sediment from soil erosion tends to clog sewers and ditches and to pollute and silt rivers, streams, ponds, lakes, and reservoirs;
3. Sediment limits the use of water and waterways for most beneficial purposes and has resulted in the deterioration of the water resources of the city.
4. Sediment reduces the channel capacity of waterways, resulting in increased chances of flooding at risk to public health and safety.
5. Adopting the standards, criteria and procedures contained in this chapter and implementing the same will address many of the detrimental effects associated with land development;
6. Adopting these standards is necessary for the preservation of the soils and topography of city as well as the public health, safety and welfare; and
7. The city has the authority to adopt an stormwater management ordinance pursuant to I.C. 36-1-3 and so that city may comply with requirements of 327 IAC 15-13.
8. Land development projects and associated increases in impervious cover alter the hydrologic response of local watersheds and may increase stormwater runoff rates and volumes, flooding, stream channel erosion, and sediment transport and deposition. This stormwater runoff may contribute to increased quantities of water-borne pollutants. Stormwater runoff, soil erosion and non-point source pollution can be controlled and minimized through the regulation of stormwater runoff from development sites.
9. Therefore, the city council established this set of water quality and quantity policies applicable to all surface waters to provide a reasonable guidance for the regulation of stormwater runoff to protect local water resources from degradation. It is determined that the regulation of stormwater runoff discharges from land development projects and other construction activities in order to control and minimize increases in stormwater runoff rates and volumes, soil erosion, stream channel erosion, and non-point source pollution associated with stormwater runoff is in the public interest and will mitigate threats to public health and safety.
B. Purpose. The city council hereby declares that the purpose of this chapter is to replace and supercede Ordinance 21-06 with a new ordinance. This new ordinance then will re-establish minimum erosion and sediment control requirements; establish minimum stormwater management requirements and controls to protect and safeguard the general health, safety, and welfare of the public by guiding, regulating, and controlling the design, construction, use, and maintenance of any development or other land altering activity which disturbs or breaks the topsoil or otherwise results in the movement of earth within the defined boundaries of the city and as specified herein. This chapter seeks to meet that purpose through the following objectives:
1. Manage stormwater runoff from any development in order to reduce flooding, siltation, increases in stream temperature, and stream bank erosion and maintain the integrity of stream channels;
2. Minimize non-point source pollution caused by stormwater runoff from development, which would otherwise degrade local water quality;
3. Manage the total volume of surface water runoff, which flows from any specific site during and following development to not exceed the pre-development hydrologic regime to the maximum extent practicable.
4. Reduce stormwater runoff rates and volumes, soil erosion and non-point source pollution, wherever possible, through stormwater management controls and ensure that these management controls are properly maintained and pose a minimal threat to public safety.
5. Adopt a stormwater design manual as recommended by the city engineer and adopted through the board of public works for specific design considerations to perform above activities. Said manuals to be modified through the board of public works as needed and recommended by the city engineer.
(Ord. 08-29, 2008)