Document: NUREG-0800
Document ID: 5657a07e-c0b2-48ce-aaad-64d91609c4b3
Document Type: srp
Title: ICE EFFECTS
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0701/ML070100648.pdf
Revision Date: 2023-06
Chapter: 2
Section ID: 2.4.7
CFR Part: 
CFR Title: 

Content:
m and ice jam formation history (e.g., from the USACE historical ice jam database) should be described to enable an independent determination of the need for including ice effects in the design basis. If the applicant’s estimates of ice effects are comparable to the staff’s preliminary bounding analysis, the staff should concur with the applicant’s estimates. If the preliminary bounding analysis indicates the applicant’s estimates of ice effects are not comparable to the staff’s estimates, the staff’s analysis should be repeated using more realistic techniques. 3. Ice Sheet Formation: Accumulated freezing degree-days data estimated from air temperatures available from CRREL may be analyzed to verify that only minimal ice sheet formation occurs on reservoirs even during severe winters. In such cases, further analysis may not be needed. If ice formation is not minimal, techniques for estimating ice sheet thickness on reservoirs such as those described in USACE publication EM 1110-2-1612, “Engineering and Design - Ice Engineering,” can be used in combination with CRREL accumulated freezing degree-days data and conservative assumptions of the ice initiation date. The volume of liquid water available under the most severe ice sheet formation should be sufficient to meet safety-related water supply requirements. 4. Ice-Induced Forces and Blockages: If floating ice is prevalent, based on regional icing history, potential impact forces on the safety-related intakes should be considered in the design basis. The dynamic loading caused by floating ice should be included in the structural design basis. If ice blockage of the river or estuary is possible, it should be demonstrated that the resulting water level in the vicinity of the site has been considered in establishing the flood (e.g., from collapse of an ice dam) and water supply design bases (e.g., low water downstream of ice jams). If this water level would adversely affect the intake structure, or other