Engineering Tools

HEC-1 HC Card Cumulative Drainage Area Calculation Tool


The software is designed to automatically calculate the drainage area at each hydrologic concentration point in an existing HEC-1 input file. View more information and download the tool.

FLO-2D Web Access Tool



Open the Viewer
This map is intended for use by experienced engineers as a design aid for preparing site drainage and grading plans, and for establishing building lowest floor elevations for new structures. Users are strongly encouraged to consult with District staff or the appropriate governing agency prior to applying this information for the first time to obtain a clear understanding of the basis for the information and for guidance in its application. The map, however, is not an official document that may be used for floodplain determination.

These maps are designed to assist in obtaining the results of two-dimensional hydrologic and hydraulic modeling prepared as a part of Area Drainage Master Studies/Plans or Floodplain Delineation Studies . The information available are estimates of the peak discharge in cubic feet per second from designated storm frequencies, the dominate direction of that discharge, and the resulting peak water surface elevation on the NAVD 1988 vertical datum. The results are the average for each grid element.

NSTPS Tool 1.0.0


Released on June 17, 2013 as a Beta version. NSTPS Tool 1.0.0 is a software package designed to automatically update the NSTPS parameter (HEC-1 RS card's first field) for flow routing in channels in an HEC-1 input file.

Drainage Design Management System


The District offers the latest version (Version 5.3.0 - April 12, 2016), as well as prior versions and upgrade versions of the DDMSW.

Manuals & Additional Resources


Search through a variety of additional resources and manuals made available online on our Flood Control District Library Catalog page or our manuals page.

Find our Best Management Practices (BMP files from Drainage Design Manual, Erosion Control).