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:
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 Channel Migration or Diversion: If ice blockage of some nearby river or estuary is possible and can impact the site, then this flood-causing mechanism is consequential to establishing the design basis flood (e.g., owing to a diverted channel as a result of an ice dam). Ice effects could also create flooding or low flow condition, resulting in adverse impacts on the operation of safety-related service water intake structure or the UHS. Should channel migration or diversion be found to be consequential at a site owing to ice effects, there should be an estimate of the most severe ice-induced channel migration or diversion effects; that estimate should be performed consistent SRP Section 2.4.7 “Ice Effects.” Flow available under the most severe channel migration or diversion conditions should be sufficient to meet safety-related water supply requirements. 8 Available online at http://www.ngdc.noaa.gov/seg/hazard/slideset/39/39_slides.shtml. 2.4.9-12 Draft Revision 4 – September 2018 4. Human-Induced Causes of Channel Diversion: In addition to the natural migration of river channels and other water courses, there also exists the potential that anthropogenic (human-induced) factors (e.g., land-use changes or the diking, channelizing, river bank armoring, and subsequent failure of such hydraulic structures) could initiate or exacerbate geomorphologic channel changes. The potential for anthropogenic-induced diversion of river channels and other water courses in the vicinity of the site should be qualitatively evaluated. The USACE and the NCHRP have proposed methods of predicting the consequences of channel migration potential near structures when the alignment of a natural river is artificially modified. 3. Flooding Effects Associated with Channel Migration or