Document: NRC Regulatory Guide
Document ID: c7b1689b-ff17-4083-9fb1-f91b6965ea1a
Document Type: regulatory_guide
Title: Design Basis Floods for Nuclear Power Plants + HISTORY - HISTORY 02/2022 – DG-1290 , Proposed Revision 3 09/2014 – Periodic Review of Revision 2 – Revise 07/1980 – Errata to Revision 2 07/2024 – DG-1290 Revision 1 (Rev. 2)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML0037/ML003740388.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.59
CFR Part: 
CFR Title: 

Content:
struction permit ap plications until this guide. is revised as a result of sug gestions from the public or additional'staff review. 1.59-8 APPENDIX A PROBABLE MAXIMUM AND SEISMICALLY INDUCED FLOODS ON STREAMS AND COASTAL AREAS The material preiiously contained in Appendix A has been replaced by American National Standards Institute (ANSI) Standard.N170-1976, "Standards for Determining Design Basis Flooding at Power Reactor Sites," with the following exception: Sections 5.5.4.2.3 and 5.5.5 of ANSI N170-1976 contain references to methods for evaluating the cro- sion failure of earthfill or roekfrdl dams and determin ing the resulting outflow hydrographs. The staff has found that some of these methods may not be conser vative because they predict slower rates of erosion than have historically occurred. Modifications to the models may be made to increase their conservatism. Such modifications will be reviewed by the NRC staff on a case-by-case basis. 1.59-9 APPENDIX B ALTERNATIVE METHODS OF ESTIMATING PROBABLE MAXIMUM FLOODS TABLE OF CONTENTS B.I INTRODUCTION ..................... B.2 SCOPE ........................... B.3 PROBABLE MAXIMUM FLOOD PEAK DISCHARGE B.3.1 Use of PMF Discharge Determinations ........ B.3.2 Enveloping Isolines of PMF Peak Discharge..... B.3.2.1 Preparation of Maps ................ B.3.2.2 Use of Maps ............. B.3.3 Probable Maximum Water Level ............ B.3.4 Wind-Wave Effects ................... B.4 LIMITATIONS ....................... REFERENCES ........................... FIGURES .............................. TABLE ............................. FIGURES Page .†.†††.†.†††.†.†††.†††††††††††††††1.59-12 1.59-12 1.59-12 1.59-12 1.59-12 1.59-12 1.59-13 1.59-13 1.59-13 1.59-13 1.59-14 1.59-15 1.59-23 1.59-15 1.59-16 1.59-17 1.59-18 1.59-19 1.59-20 1.59-21 1.59-22 Figure B. I-Water Resources Regions ..................... B.2-Probable Maximum Flood (Enveloping Isolines)-100 Sq. Mi.