evacuation and reoccupation, flood fighting, and 

 disaster relief; increased costs of normal operations 

 during the flood; and increased costs of police, fire, 

 or military patrol. Emergency costs should be deter- 

 mined by specific survey or research and should 

 not be estimated by applying arbitrary percentages 

 to the physical damage estimates. 



2.4.3 Planning setting. 



(a) General. The benefit of flood hazard reduction 

 plans IS determined by comparison of the with- and 

 without-project conditions. 



(b) Without-project condition. The without-project 

 condition is the land use and related conditions 

 likely to occur under existing improvements, laws, 

 and policies. There are three significant assump- 

 tions inherent in this definition; 



(1) Existing and authorized plans. Existing flood 

 hazard reduction plans are considered to be in 

 place, with careful consideration given to the actual 

 remaining economic life of existing structures. 

 Flood hazard plans authorized for implementation 

 but not yet constructed are evaluated according to 

 the relative likelihood of actual construction. If there 

 is a high likelihood of construction, the authorized 

 plan is considered to be in place. 



(2) Flood Disaster Protection Act. The adoption 

 and enforcement of land use regulations pursuant 

 to the Flood Disaster Protection Act of 1973 (Pub. 

 L. 93-234) is assumed. 



(i) Regulation certified or near certification. If the 

 local land use regulation has been or will be certi- 

 fied, partially waived, or adjusted by the Flood In- 

 surance Administration (FIA) as adequate under 24 

 CFR 1910.3 (c) and/or (d) and 24 CFR 1910.5, that 

 regulation defines the without-project condition. 



(ii) Regulation not yet certified. It is assumed that 

 the local jurisdiction will adopt in the near future 

 land use regulations certifiable to FIA under the 

 without-project condition as a datum and under the 

 with-project condition if a residual hazard will 

 remain. This applies to floodplains regulated under 

 24 CFR 1910.3 (a) and (b); to floodplains regulated 

 by local ordinances independent of FIA; and to 

 floodplains with no flood regulation in effect. For ri- 

 verine situations, the following two crucial features 

 are included: no future confinement or obstruction 

 of the regulatory floodway; and no future occupan- 

 cy of the flood fringe unless residences are elevat- 

 ed to or above the 100-year flood level and nonre- 

 sidences are floodproofed to that level. 



(iii) Application. It is assumed that floodproofing 

 costs will be incurred if an activity decides to locate 

 in the floodplain. 



(3) Executive Orders. Compliance with E.O. 

 11988, Floodplain Management and E.O. 11990, 

 Protection of Wetlands, is assumed. 



(4) Individual actions. In addition to the three as- 

 sumptions stated in paragraphs (b) (1), (2), and (3) 

 of this section, the analyst shall consider the likeli- 

 hood that individuals will undertake certain flood 

 hazard reduction measures, such as flood proofing, 

 when the cost of such noasures is reasonable 

 compared to the costs of potential flood damages. 



(c) With-project condition. The with-project condi- 

 tion is the most likely condition expected to exist in 

 the future if a specific project is undertaken. There 

 are as many with-project conditions as there are al- 

 ternative projects. 



(1) In projecting a with-project condition, the ana- 

 lyst must be sensitive to the relationship between 

 land use and the characteristics of the flood hazard 

 for the alternative project being analyzed. 



(2) The same assumptions underlie the with-pro- 

 ject and without-project conditions. 



(3) Consideration should be given to both struc- 

 tural and nonstructural alternatives and to alterna- 

 tives incorporating a mix of structural and nonstruc- 

 tural measures. Nonstructural measures include: 



(i) Reducing susceptibility to flood damage by 

 land use regulations, redevelopment and relocation 

 policies, disaster preparedness, flood proofing, 

 flood forecasting and warning systems, floodplain 

 information, floodplain acquisition and easements; 

 and 



(ii) On-site detention of flood waters by protection 

 of natural storage areas such as wetlands or in 

 manmade areas such as building roofs and parking 

 lots. 



(4) Since project alternatives can differ in their 

 timing as well as in their physical charactenstics. 

 the optimal timing of projects and of individual pro- 

 ject features should be considered in project formu- 

 lation. 



2.4.4 Evaluation procedure: General. 



Ten steps are involved in computing benefits 

 (see Figure 2.4.4). The steps are designed primarily 

 to determine land use and to relate use to the flood 

 hazard from a NED perspective. The level of effort 

 expended on each step depends on the nature of 

 the proposed improvement and on the sensitivity of 

 project formulation and justification to further refine- 

 ment. The first five steps result in a determination 

 of future land use; emphasis is on evaluating the 

 overall reasonableness of local land use plans with 

 respect to (a) OBERS and other larger area data, 

 and (b) recognition of the flood hazard. 



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