N.H. Code Admin. R. Env-Wr 502.07

Current through Register No. 25, June 20, 2024

Section Env-Wr 502.07 - Breach Routing Methods

(a) The owner shall use one of the following routing methods for dam breach analysis:

(1) Methods and procedures used by the United States Department of Agriculture, Natural Resources Conservation Service in:

a. Technical Release T.R. 66 "Simplified Dam Breach Routing Procedures", 1985, available as noted in Appendix B;

b. Computer Program for Project Formulation Hydrology, T.R. 20, 1992, available as noted in Appendix B; and

c. WSP 2 Computer Program, T.R. 61, 1993, available as noted in Appendix B, which shall be used in conjunction with each other;

(2) Methods and procedures using the National Weather Service Dam-Break Flood Forecasting Model authored by Dr. Danny L. Fread, from the National Weather Service in Silver Springs, Maryland, dated 1987, available as noted in Appendix B; or

(3) Methods and procedures for dam breach simulation and routing developed by the U.S. Army Corps of Engineers' Hydrologic Engineering Center, and incorporated in HEC-RAS, version 4.1, 2010, available as noted in Appendix B.

(b) An owner wishing to use other techniques for breach routing shall submit a written request for approval of the technique to the department for each particular site prior to using the technique. The request shall contain a description of the technique, including how the technique addresses the parameters addressed by the techniques identified in (a), above.

(c) If the department determines that the technique can be correctly applied to the hydrologic and topographic conditions of the dam and downstream area, within the limitations and capabilities of the modeling technique, and that it will provide the detailed information required by these rules, the department shall approve the technique for use on that site and shall so notify the owner in writing.

(d) The department shall not require previously-approved dam breach analyses that were completed using methods other than those specified in (a), above, to be reassessed using those methods, provided, however, that if an expansion of the breach analysis is required pursuant to Env-Wr 502.04, the owner shall use a technique specified in (a) or approved pursuant to (b) and (c), above.

N.H. Code Admin. R. Env-Wr 502.07

#8414, eff 8-20-05; ss by #10510, eff 1-22-14