Technical Tools

HEC-1 HC Card Cumulative Drainage Area Calculation Tool
View more information and download the tool.

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

FLO-2D Web Access Tool
Open the map

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: June 17, 2013 (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 latest version (Version 5.6.0 - August 2018), as well as prior versions and upgrade versions of the DDMSW, are available via this website for free download.

The DDMS is a Windows tool that was initially developed as a pre-processing tool for HEC-1 modeling. Additional functionalities have been added; which include Storm Drainage Hydraulics and River Mechanics.

Flood Control District Library

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

Commonly Downloaded Manuals

Best Management Practices

Best management practices (BMPs) help control urban storm runoff by reducing runoff and improving water quality from storm events. BMPs include structural controls such as infiltration devices, ponds, filters and constructed wetlands, and non-structural controls such as maintenance practices, street sweeping, public education and outreach programs.

View individual drawings of our Best Management Practices (BMP) as PDF files or alternatively, you can download the entire set of BMP Drawings as DGN files.