Document: NUREG-0800
Document ID: 496b5bd8-c9a2-4cf6-a703-e41c51e155ec
Document Type: srp
Title: CHANNEL MIGRATION OR DIVERSION
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1819/ML18190A201.pdf
Revision Date: 2023-06
Chapter: 2
Section ID: 2.4.9
CFR Part: 
CFR Title: 

Content:
omestic Licensing of Production And Utilization Facilities”) requires that nuclear power plant SSCs important to safety be designed to withstand the effects of natural phenomena such as earthquakes, tornadoes, hurricanes, floods, tsunami, and seiches without loss of capability to perform their intended safety functions. The Commission’s reactor siting criteria at §100.20(c)(3) also call for the estimation of the “… maximum probable flood … using historical data ….” Floods (or flooding), as represented by the maximum probable flood (PMF), is thus one of the site characteristics1 to be evaluated in the context of GDC 2. The key parameters in estimating the PMF at a nuclear power plant are the calculation of a water surface elevation that would occur across the footprint of the power plant site in relation to SSCs important to safety, duration of the flooding event, and associated effects. The scope of this SRP section involves the review of an applicant’s estimate of the site characteristic flood at a power plant site due to channel migration or diversion. In examining the site characteristic flood, staff’s review approach should be hierarchical. The staff would first review the applicant’s determination, based on geographic considerations, of whether there is the potential for channel migration or diversion at the power plant site. If this flood-causing mechanism is considered to be physically possible, then the staff would review the applicant’s determination of whether channel or diversion could result in consequential flooding of the site. If consequential flooding is determined to be possible, then the staff would review the applicant’s flood inundation map2 depicting the extent and elevation of flooding across the powerblock due to the effects of channel migration or diversion. In addition to a flood inundation map, the staff would review applicant’s calculation of the duration of the flooding event as well as any associated effects.3