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:
revetment, or alluvial channel meander changes. C. Upstream (or downstream) and within the bank and due to climatic/ meteorological causes such as ice-jams. Evaluate the geographic layout of existing channel meanders, cross-sections (widths and depths), profiles (slopes), estimated discharge properties (velocity and energy), and material compositions for beds and banks and, suspended loads. 2. Regional Topographic and Geologic Evidence of Channel Migration or Diversion: In addition to the a review of historical geologic/geomorphic information, the review should also determine if there is regional topographic as well as geologic evidence suggesting the potential for future channel migration or diversion. For example, there is the possibility that diversion effects could change existing water course paths through debris blockage, tectonic uplift, or subsidence. Potential migration or diversions effects that can result from gradual progressive causes, or from quick catastrophic changes should be considered. If considered necessary, identify the most likely types of channel migration or diversion conditions and the potential impact on plant siting and design of each type. For each type of condition, preliminary independent conservative estimates of the “worst case” should be made qualitatively. There are geospatial databases that contain information including topographic maps and geologic maps that can be used to qualitatively determine candidate locations where geologic or human-induced events increase the likelihood of channel migration or diversion. The USACE (Cherry and others, 1994) and the NCHRP (National Research Council, 2004) have proposed recommended methods for predicting channel migration. The USGS8 and several state Departments of Natural Resources have compiled geospatial databases depicting landslide hazards. The Federal Emergency Management Agency (FEMA, 1999) has conducted riverine erosion hazard area mapping studies. 3. Impact of Ice Effects on