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Base Level Engineering (BLE) Tools and Resources

Tools, templates and resources in the searchable list below assist communities for the local review and incorporation of Base Level Engineering datasets in their floodplain management activities. These tools connect up with BLE data available, free-of-charge, on the interactive on-line portal, known as the Estimated Base Flood Elevation (estBFE) Viewer

Resources below are intended for use by state, tribal and local elected officials, technical community departments/staff, engineering and development industry, community and natural hazard planning staff across the nation. 

There are various resources assist in the collection, review and utilization of the data to promote risk reduction and smart growth initiatives across the nation.

Search for Resources

Using the Estimated BFE Viewer

4 page, booklet style – overview of BLE concept, estBFE viewer and uses for data all in one (11x17 print).

Overview – What is Base Level Engineering?

BLE approach, concept and data uses included in this overview document.

Pages – State Quick Guide

Intended for consistent release of BLE across the nation. Provides materials for incorporation into existing State Quick Guides. Connects with estBFE Viewer.

Flash Card – BLE Data Downloads

Assists in determining which downloads contain the information you need. Connects with estBFE Viewer.

Flash Card – BLE Vector GeoDatabase

Provides insight to the various spatial datasets available in the Vector Geodatabase. Connects with estBFE Viewer.

Flash Card – BLE and LOMAs

Steps on how to create site specific report and use it for LOMA submittal. Connects with estBFE Viewer.

BLE as Best Available Information

BLE may be used in a number of situations. This document overviews when BLE may be applied for use based on the guidance for best available information use.

BFE Interpolate Tool

Excel file with programming to assist locals in determining BFE for structures outside floodplain. If you need further assistance accessing this document, please contact Diane Howe at diane.howe@fema.dhs.gov.

HOW2 Determine BFE with BLE Data (1D and 2D)

Step by step instructions to use BLE database and raster files to determine Base Flood Elevations for structures/projects outside of floodplain. Uses BFE Interpolate tool for 1D and includes assessment instructions for 2D results as well. Requires GIS software.

HOW2 – Estimated BFE Viewer

Placemat providing detail on how to use the estBFE Viewer. Use as computer aid in libraries or at interactive delivery settings.

HOW2 – Find the Right HEC-RAS Model

Step by Step instructions to assist finding the model needed. Connects with estBFE Viewer.

HOW2 – Find the Right Spatial Files

Step by Step instructions to assist finding the spatial files of interest. Connects with estBFE Viewer.

Informed Development with BLE

This module provides an overview of how BLE may be used by engineering/development industry and local communities to assure informed development decisions.

Local Permitting Checklist

Tool provides the basis for local floodplain development reviews, refers to FIRMs and Base Level Engineering information.

Fact Sheet – Water Surface Elevation Grids

Describes what information is included in a Water Surface Elevation Grid and how they can be used by various user groups.

Fact Sheet – Flood Depth Grids

Describes what information is included in a Flood Depth Grid and how they can be used by various user groups.

BLE, Social Media & Flood Risk Awareness

Communication resources and social media content to promote flood risk awareness and BLE data use.

HOW2 – BLE Use Matrix

Includes a Use Matrix to decipher when BLE data can be used as Best Available Data, and when it can’t. Connects with estBFE Viewer.

BLE and Letters of Map Revision

Provides details on how to review effective FIRMs and BLE data to determine Base Flood Elevations for both LOMA and LOMR-F submittals.

BLE and Letters of Map Amendments

Provides details on how to review effective FIRMs and BLE data to determine Base Flood Elevations for both LOMA and LOMR-F submittals.

LOMA (Out as Shown)

Connects with Map Service Center, National Flood Hazard Layer and estBFE Viewer.

Last updated September 1, 2020