Document: NUREG-0800
Document ID: b3542dd9-b995-4eba-aa6c-0f8f08f8c772
Document Type: srp
Title: FLOODS
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0523/ML052340525.pdf
Revision Date: 2023-06
Chapter: 2
Section ID: 2.4.2
CFR Part: 
CFR Title: 

Content:
f will review publications of the U.S. Geological Survey (USGS), National Oceanic and Atmospheric Administration (NOAA), Soil Conservation Service (SCS), Corps of Engineers, applicable State and river basin agencies, and others to ensure that historical maximum events and the flood response character- istics of the region and site have been identified. Similar material, in addition to applicant-supplied information, will be reviewed to identify independently the potential sources of site flooding. For SAR Section 2.4.2.2 (Flood Design Considerations): The potential flood levels from consideration of the worst single phenomenon and combinations of less severe phenomena are identified in accordance with SRP Sections 2.4.3 through 2.4.7 and the controlling flood level is selected. The controlling flood level is compared with the proposed protection levels to ensure that the safety-related facilities will not be adversely affected. If appropriate, additional provisions for flood protection will be imposed to ensure adequate protection of the safety-related facilities. For SAR Section 2.4.2.3 (Effect of Local Intense Precipitation): The staff's estimates of flooding potential are based on PMP estimates from 2.4. 2-4 Rev. 3 - April 1989 the appropriate hydrometeorological reports and similar NOAA publications. The staff's estimates are compared with the applicant's estimates to determine conformity to Acceptance Criteria in subsection II of this SRP section. Runoff models, such as the unit hydrograph if applicable, or other runoff discharge estimates presented in standard texts, are used to estimate discharge on the site drainage system. Where generalized runoff models are used, coefficients used for the site and region are compared to information available at documented locations to evaluate hydrologic conditions used in determining the probable maximum flood for the site drainage system. Potential ponding on the site is also determined. The above reviews are performed