FLOOD03020 - Laserfiche WebLink

Home Browse Search

Local government officials have two sets of approach€!s to choose from when they decide to deal with flooding problems, preventive (non-structurall and corrective (structural). Preventive Approaches 1) Floodplain Management Regulations u zoning ordinances, subdivisIon regulations, planned unit development, building codes, 1041 permit sys- tem,etc. 2) Development Policies ~~ open space, publiC serviC13S and facilities. taxa- tion, urban redevelopment, flood control and storm drainage facility fee structure, etc, 3) Flood Insurance 4) Emergency Preparedness 5) Education/Awareness Corrective Approaches 1) Flood Control -- darns, reservOirS, detention and retention ponds, watershed treatment, levees and floodwalls and channel improvements. 2) Floodproofin(j -., Changes to new or existing structures to reduce or eliminate flood damages by protecting aga.inst structural failure, keep- ing water out, or reclucing the effect of water entry Local, State, and Federal floodplain managers have encountered problems when using only the corrective approach. Frequently, tl1e risk of property ciamage and loss oi life I.as actually been increased afler structural improvements have been built because encroachment in the floodplain is a.ilowed to continue. These improvements can also prOVide people with a /;llse sense of security and thereby encourage such encroachment. Recent experience has demonstrated that a combination of corrective and preventive approaches can be more time and cost effective. In terms of cost. t1e preventive approaches are usually less expensive, In some communities, rowever, the large amount of existing development in the floodplain pre- cludes using only the pn~ventive approach. CHAPTER 4 FLOODPLAIN MANj~GEMEI\I'" ALTERNATIVES -~- "A~6 ~~ - Preventive Measures (1I\Ion- Structural Approaches) L.and Use Regulations 2:oning Z.oning is the most common flood- plain management regulatory tool used by local governments in Colorado. Floodplain zoning rellula- tlons consist of maps and written tox!. The maps (approximate & detailed) delineate floodplain areas of the community, are based on engineering information, and allow precise regulation of the floodplain. The text decribes Hstablished mini- mum standards for the use of the lands delineated on the maps. One or more zoning districts and subdistricts are created by the mgulations basHd on adopted flood- plain maps and studies. Land uses in those districts are either prohibited, permitted subject to conditions or rHstrictions, or permitted without conditions. Variances aro provided under appropriate mitigating cir- cumstances. Any proposed develop- ment or substantial improvement of existing property within the districts 25 must meet the requirements of the regulations. Provisions are made for amending the maps (rezoning) based on sound technical data. The zoning regulations are generally based on the "overlay" concept where an area is subject both to the restrictions of the underlying zoning district and to the restrictions of the flOOdplain zoning district which overlays it. In some cases communi- ties have designated one or more separate zoning districts for flood- plain areas which have their own res- trictions and are unrelated to any other zonin(j districts, The decision whether to follow the overlay con- cept or to create separate zoning districts can be made by the loca' govEirnment. Communities that are downstream of dams can consider some sort of zoning desiqnation for all or part of the "dam failure flood zone." Such a desi!)nation could control develop- ment downstmam of a dam to reduce the threat of dam failure flood damage.