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Planning Guidance: Dam and/or Levee Safety
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Guidance Memos This Memorandum covers the actions that must be taken within the planning phase of the USACE Civil Works project delivery process in order to embrace and operationalize risk informed decision making. The Memorandum includes delegations for Feasibility Milestone decision making, as well as delegation of Policy Review. Engineer Circulars (ECs) The purpose of this circular is to expand and tailor current federal guidelines for dam emergency action planning and other available resources for implementation within the USACE Dam and Levee Safety Programs. Because there are no federal guidelines for emergency action planning for levee systems, USACE has chosen to apply the same approaches for dam emergency action planning to levee systems. This document establishes the requirements for consistent application of certain key Emergency Action Plan (EAP) features for USACE operated/maintained dams or levee systems. This document also serves as an advisory document for use by other project owners/operators and provides policy for the use and dissemination of inundation map data. Engineer Pamphlets (EPs) Engineer Pamphlet provides preliminary guidance and direction for the earthquake-resistant design of new roller compacted concrete (RCC) dams, and for the evaluation of safety and serviceability of existing RCC dams subjected to earthquake loading. Engineer Pamphlet provides general guidance and information concerning dam safety preparations for USACE. Engineer Pamphlet evaluates procedures for major rehabilitation where risk-based benefit-cost analysis is used. This guidance provides a conceptual approach for analyzing rehabilitation. It requires risk-based benefit-cost analysis and criteria. This appendix outlines basic procedures that can be used to evaluate rehabilitation for navigation and hydropower project purposes. Engineer Regulations (ERs) This regulation establishes the roles and responsibilities of the Dam Safety Modification Mandatory Center of Expertise (DSMMCX) located within the Huntington District, U.S. Army Corps of Engineers (USACE). This regulation establishes the roles and responsibilities of the Risk Management Center (RMC) located within the Institute for Water Resources, USACE. This regulation provides guidance and procedures for the investigation and justifications of modifications for dam safety assurance. This regulation prescribes the guiding principles, policy, organization, responsibilities, and procedures for implementation of risk-informed dam safety program activities and a dam safety portfolio risk management process within the United States Army, Corps of Engineers (USACE). This regulation establishes the policy for the operation and maintenance (O&M) of USACE flood control and related structures at civil works water resource projects and of USACE-built flood protection projects operated and maintained by non-federal sponsors. This regulation sets guidance for USACE implementation of Order 11988, Floodplain Management, as it pertains to civil works projects in design and construction. Engineering and Construction Bulletins The U.S. Army Corps of Engineers (USACE) will use this directive and guidance for commands responsible for planning, design, construction, and operation and maintenance of civil works projects. The procedures are general in nature and can be applied to any phase of study, as directed by Engineer Regulation (ER) 1110-2-1150. The level of detail in the overtopping analysis will depend on the study phase. This document is applicable for all USACE riverine levee and floodwall systems. This Engineering and Construction Bulletin (ECB) provides an interim update to expired technical guidance Engineer Technical Letter (ETL) 1110-2-299 and provides a methodology for configuring the engineered capacity exceedance related to flood overtopping at a specific location or locations along the levee system. This guidance does not address overtopping of the entire system on those occasions when the overall system capacity is exceeded. This ECB has expired and was updated by ECB 2019-8. This Engineering and Construction Bulletin (ECB) outlines concepts, goals and provides interim guidance for the engineering and construction components associated with planning studies under the Director's Policy Memorandum CW 2018-05 issued in May 2018, Improving Efficiency and Effectiveness in USACE Civil Works Project Delivery (Planning Phase and Planning Activities). A maxim of execution is that expedience is not to be prioritized over sound engineering judgment. The concepts in this ECB can also be applied, as appropriate, to other risk-informed efforts. Engineer Pamphlets (EPs) This pamphlet explains the benefits of, and requirements for, stakeholder engagement, collaboration, and coordination in Civil Works planning studies. These activities are critical to study success because they may foster trust and credibility between USACE and the communities we serve; increase collective understanding of problems; reduce controversy and litigation risks; and improve the quality and execution of our decisions. Note: This EP replaces the existing Appendix B of the Planning Guidance Notebook. Institute for Water Resources Guidance Memos This memorandum addresses the requirement to perform mitigation when proposed USACE flood-risk reduction projects increase the Base (1-percent-annual-chance) Flood Elevation (BFE). National Flood Insurance Program (NFIP) regulations (44 C.F.R. 65.12) require revisions to flood insurance rate maps to reflect BFE and/or floodway changes caused by encroachments permitted by an NFIP participating community. Memorandums of Agreement and Understanding This Memorandum of Agreement between the Federal Emergency Management Agency (FEMA) and the Department of the Army underscores the policy of both agencies to facilitate the use of non-structural approaches to reducing flood damages where practicable, and that the construction of levees on Hazard Mitigation Grant Program (HMGP) lands is incompatible with open space uses and, therefore, will not be recommended for implementation. The restriction on levee construction generally does not apply to structures designed specifically for ecosystem preservation, restoration, or enhancement. Structures for these purposes are deemed consistent with the open space uses requirement of the HMGP. Institute for Water Resources Planning Bulletins The purpose of this planning bulletin is to provide further clarification on policy with respect to evaluation of nonstructural measures. This bulletin supplements Planning Bulletin 2016-01, Clarification of Existing Policy for USACE Participation in Nonstructural Flood Risk Management and Coastal Storm Risk, which is still in effect. This Planning Bulletin provides information on the use of life safety in the planning process. Risks to human life are a fundamental component of all facets of flood and coastal storm risk management and must receive explicit consideration throughout the planning process. The bulletin augments, but does not supersede, the procedures in Engineer Regulation 1105-2-100, Planning Guidance Notebook and Engineer Regulation 1105-2-101, Risk Assessment for Flood Risk Management Studies. This document applies to all flood and coastal storm risk management feasibility studies, including those conducted under the Continuing Authorities Program and studies conducted by non-federal interests under Section 203 of WRDA 1986, as amended. Note: the POC for the Dam and Levee Senior Oversight Groups is Brad Arcement, MVK. Guidance Memos This memorandum from the Assistant Secretary of the Army (Civil Works) (ASA(CW)) articulates Army policy: "It is the policy of the Army to encourage floodplain restoration, as it encourages community resilience and provides benefits to both the ecosystem and human wellbeing. The use of levee set-backs, along with other measures to increase and enhance floodplains, is encouraged in aquatic ecosystem restoration projects. It is also the policy of the Army not to increase flood risks or decrease life safety without sufficient justification. When formulating restoration projects that propose restoring floodplains, the Corps should use the existing level of flood risk as the formulation baseline. If any changes to the baseline are recommended, then the Corps should demonstrate the rationale for the increase or decrease in the level of flood risk management. If the level of flood risk associated with an ecosystem restoration project is decreased, then the risk reduction increment above the baseline must be cost effective and incrementally justified. If the level of flood risk is increased as a result of ecosystem restoration, then the Corps must mitigate any induced damages as part of the restoration project." In the memo, the ASA(CW) concurs with the recommendation that the implementation of setback levees are a necessary project feature of the recommended plan to mitigate for induced flooding, and without moving the levees, minimal to no restoration benefits are achievable that meet the planning objective. Institute for Water Resources The analytical review and summary critique of literature related to risk analysis was conducted for the purpose of highlighting those ideas, concepts and methods that have a bearing on conventional approaches to evaluating uncertainties of natural and technological hazards and the risks imposed by alternative solutions. The critique of the philosophical and analytical bases of risk analysis was further directed toward the specific problem of dam safety risk analysis. Dam safety is unique in that it represents an extreme situation characteristic of a low probability/high consequence event. Conventional rules of economic analysis are difficult to extrapolate and extend to such events. This analytical review was conducted as part of the Corps' Risk Analysis Research Program, managed by the Institute for Water Resources, of which the dam safety risk analysis research effort is but one part of the broader range of applications of risk analysis to Corps problems.
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