Levee certifications

Section 3014 of the Water Resources Reform and Development Act of 2014 (42 U.S.C. 4131) is amended by adding at the end the following: (c) Rulemaking (1) In general Not later than 180 days after the date of enactment of this subsection, the Secretary, in coordination with the Administrator and the Committee on Levee Safety established under section 9003 of the Water Resources Development Act of 2007 (33 U.S.C. 3302), shall initiate a rulemaking to establish the methodology or process by which the Secretary shall conduct a risk assessment in evaluating a levee under subsection (b). (2) Requirements In issuing the rule under this subsection, the Secretary shall— (A) evaluate— (i) multiple methodologies for conducting risk assessments, including deterministic and probabilistic methods; and (ii) the significant differences between each method with respect to— (I) cost of using each method; (II) reproducibility of results; (III) level of confidence in results produced by each method; (IV) how each method accounts for flood risk assessment and management implications, including risk to human life and property; (V) economic impacts; and (VI) other relevant factors; and (B) provide for a public notice and comment period of not less than 90 days. (3) Definitions In this subsection: (A) Deterministic method The term deterministic method means, with respect to levee evaluations under this section, a physical-criteria-based evaluation that determines compliance with the 1-percent-annual chance flood event standard set forth in section 65.10 of title 44, Code of Federal Regulations, as in effect on the date of enactment of this subsection, by measuring levee performance against specific, fixed physical margins, including freeboard, embankment protection, closure devices, and structural stability, to establish a binary determination of structural adequacy. (B) Probabilistic method The term probabilistic method means, with respect to levee evaluations under this section, a statistical-inference-based evaluation used as an alternative or supplement to a deterministic methodology to determine the likelihood of levee failure or overtopping during a 1-percent-annual chance flood event, through the use of— (i) system response curves or fragility curves, which define the conditional probability of failure as a function of water stage or load; (ii) Monte Carlo simulations or similar stochastic modeling used to propagate uncertainty in hydrologic, hydraulic, or geotechnical parameters; and (iii) catastrophe models or proprietary risk-rating algorithms used to determine flood insurance premiums or levee safety action classifications..