The CWMS Data API (CDA) is a Representational State Transfer (REST) API that enables secure data exchange between computer systems over the internet. With the decommissioning of the National CWMS Database at the Central Processing Center (CPC) and the aging district T7 servers reaching end-of-life, a modern, accessible solution was needed to manage Water Management data. The new solution is a cloud-based database system, offering improved scalability, flexibility, and security.

CDA acts as the interface between HEC-RTS and this cloud environment, allowing users to securely send and retrieve time series data through a web connection. HEC-RTS now supports data extraction directly from CDA, streamlining access to water management data. General information about CDA can be found on GitHub. 

This guide explains how to configure CDA access and set up an Extract Group in HEC-RTS to pull data from the CWMS Data API.

Step 1: Configure the Login Information

Before using CDA in HEC-RTS, you must configure your connection and login credentials.

  1. Launch HEC-RTS.
  2. Select Login under the File menu.
  3. The CWMS Login Dialog will open. Click on the Login Setup button.
    CWMS Login Dialog
  4. From the Edit menu, select Add Data Source and then CWMS Data API. 
  5. Enter the following details:
    1. Display Name: Enter a custom name to identify this connection (e.g., CDA National) 
    2. Host URL: Use the appropriate CDA instance url.
      1. For the National Database, use http://cwms-data.usace.army.mil/cwms-data/

    3. Office: Select the appropriate office from the dropdown. 

  6. Click OK to save and close the dialog.

Authentication via CWMS AAA is not supported for the National Database or CWBI Test environments in CWMS 3.4. However, it is available for district-level CDA instances.

Step 2: Create a New Extract Group for CDA

Refer to this guide for step-by-step instructions on creating a new Extract Group.

  1. Within the New Extract Group dialog, enter a Name for the new group. 
  2. Set Type to Time Series.
  3. Set Source to CWMS Data API.  
  4. Choose the appropriate Data Store from the available options.
  5. Configure the Storage Options and Time Window Settings.
    1. Refer to the guide for more details, if needed.
  6. Check Run by Default if you want the group to run automatically during forecast creation.
  7. Click OK to create the Extract Group.

Final Steps: Add Data to the Extract Group

Return to this guide and follow the instructions under Steps 4 and 5 to add data to your Extract Group.