Pre-Analysis Communication Best Practices

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Purpose

This page presents a framework for an engineer/modeler to communicate plans for hydrologic, hydraulic, seepage, and stability models to both a dam owner and regulatory agency. There are a variety of approaches and methodologies for these modeling efforts, and it is important to owners, consultants, and regulators that clear communication is integrated in the process. The purpose of this page is to guide communication among all interested parties prior to commencing a modeling effort. Such pre-modeling communication may include a project scoping meeting, a scope of work, and/or a modeling work plan submittal or meeting with a regulator.

The need for clear communication is apparent in these unfortunate but common dam modeling scenarios:

• A consultant, working on behalf of the dam owner, evaluates an existing structure for seepage and stability performance. The dam owner submits the findings of the modeling effort in a report to the regulator. The regulator reviews the modeling report and responds to the owner with many comments, some of which contest the initial assumptions made by the consultant. The owner, consultant, and regulator attempt to resolve the comments and revise the model and report several times at the expense of the owner’s budget and schedule.
• A consultant, working on behalf of the dam owner, develops a hydrologic model used to model a dam’s inflow design flood (IDF). The regulator recently published updated guidance documents for hydrologic modeling and IDF development. The consultant develops and submits the model based on the previous guidelines. The regulator reviews the modeling report and asks for a resubmittal using the new guidance documents before further comments are made. The consultant is then required to redevelop the model and resubmit, at the expense of the owner’s budget and schedule, prior to the detailed regulatory review.
• The modeling project and expected review timelines are not communicated to the regulator at the start of a modeling effort. Once the modeling report is submitted, the regulator, who is understaffed, is not able to review the report for over a year at the expense of the owner’s schedule and potentially public safety, should the model be used to inform future design efforts to address dam deficiencies.

The following sections outline best practices for pre-analysis communication and scope development to hopefully avoid situations such as these.

Levels of Pre-Analysis Communication

The complexity and degree of pre-analysis communication will vary from project to project and exists on a spectrum as illustrated above. For simple modeling efforts, email correspondence or a brief proposal may be an adequate level of pre-analysis communication. For more complex or impactful efforts, all of these methods of communication may be needed to adequately plan the modeling effort. The following factors may influence the level of pre analysis communication on the spectrum:

• Hazard classification or potential downstream consequences of the dam to be modeled

• Modeling purpose (i.e., screening level study, rehabilitation design, risk assessment, hazard reclassification, emergency planning)

• Public interest or involvement in the project

• Technical complexity of the analysis

• Unknowns and data gaps in the analysis and potential for dam safety risks during data acquisition (e.g., bore holes through an embankment dam)

• Level of previous experience with the dam, owner, and/or regulator

• Regulator familiarity with the dam, behavior of the type of dam, geology of the region, and potential loading

• Importance of model in directing critical design decisions

• Level of experience / validation of the analysis method in standard practice

• Availability of regulator guidelines and whether model will be able to follow guidelines

This spectrum should be considered when applying the following steps during the planning of future modeling efforts.

Steps of Pre-Analysis Communication

1. Develop Project Understanding and Objectives
2. Develop Scope of Work
3. Obtain Concurrence from Regulatory Agency
4. Proceed with Modeling and Keep Communication Channels Open

Resources for Developing a Model Work Plan

Whether it consists of an email or a comprehensive proposal, a model work plan should address an understanding of the model objectives, project constraints, and overall approach. Additional items that should be considered when developing this plan are summarized on this page: Developing a Model Work Plan. This includes considerations for specific model applications including seepage analysis, slope stability analysis, hydrologic analysis, hydraulic analysis, and consequence estimation.

Development of this page was sponsored by the Montana Department of Natural Resources & Conservation with funding from the FEMA Assistance to States Grant Program.

Revision ID: 8029
Revision Date: 08/27/2024