Simplified Water Allocation Models (SWAM)

Public Release

The South Carolina Department of Natural Resources (SCDNR) is pleased to announce the public release of the Simplified Water Allocation Models (SWAM) for the Edisto, Saluda and Salkehatchie river basins. These models are being made available via this FTP Site. A folder is listed for each basin and each folder includes the following files:

  1. Excel file, with extension .xlsm containing the SWAM Baseline Model.
  2. South Carolina Surface Water Quantity Model Report for the basin.
  3. Supplemental Technical Memorandums, if any, regarding any updates or changes to the model since the initial model report was released.
  4. An SCDNR Model Review Technical Memorandum, if available, describing any important limitations or other considerations for using the SWAM model in a given basin.

Users should carefully review the modeling report and any technical memorandums included in each basin folder prior to using the model. Users are also strongly encouraged to review the SWAM User’s Manual (v5.0) that is available on the FTP site under the User’s Manual folder.


The SCDNR, in collaboration with the South Carolina Department of Health and Environmental Control (SCDHEC), awarded a contract to CDM Smith, Inc. in August 2014 for the purpose of developing surface water quantity models using the SWAM modeling tool. The SWAM models are intended to support the development of regional water plans for each of the eight major river basins in the State. Information on the State’s water planning efforts can be found on the SCDNR website and at

System Requirements

Minimum system requirements for using the SWAM models include Microsoft Excel 2013 and a computer with 8 GB of RAM.

Model Updates

The SCDNR has made tremendous efforts to ensure the accuracy of data included in the model but cannot guarantee that data inputs are error free. Models will be updated as necessary and a log describing any changes or updates to the model will be included in each basin’s subfolder. To ensure access to the most recent model, users are encouraged to access the model directly from this public site.


Each individual user should download his or her model(s) of interest directly through this public access site. The distribution of the models to other potential users is strongly discouraged.

Notice and Disclaimer

The South Carolina Department of Natural Resources is providing free public access to the SWAM models and associated data. The SWAM models were developed for the purpose of providing general water availability information and are intended to support the development of regional water plans in each of the eight major river basins in the State. The model is not designed or intended to function as a site specific engineering or hydraulic model. The models are based on the available data at the time of development. Although the models and data have been subjected to rigorous review and are substantially complete, the SCDNR reserves the right to revise the models and data pursuant to further analysis and review. Updated models may subsequently be released and made available to the public.

Though the models are being made available for personal use to interested stakeholders, the SCDNR is not obligated to review or comment on individual applications of the model. The agency is also not responsible for the misuse or misapplication of the model, and any person or entity that relies on the SWAM model does so at his or her own risk.

The SCDNR, including any board member, officer, or employee, does not warrant the function of the SWAM models and shall not be liable for any losses caused by such reliance on the operation of the SWAM models, including, but not limited to, incidental and consequential damages. The access to and distribution of the SWAM models is provided 'as is' without warranty of any kind, either expressed or implied, including, but not limited to, the implied warranties of merchantability, fitness for a particular purpose or non-infringement. The SCDNR maintains all immunities and defenses provided in the South Carolina Tort Claims Act and otherwise provided by law.

Download Models

You can access the FTP site by filling out the form below. You will be asked for basic information about how you plan to use the models. After completing this survey, you will be given the URL to the FTP Site.

Once on the FTP site, click on the name of the folder corresponding to the basin of interest. Select the file(s) of interest and then click, hold and drag the file to the desired folder on the local computer.

Download Water Models

Contact Information

For any issues regarding the download and use of the models or to report potential data input errors, please contact Scott Harder ( with the SCDNR or Rob Devlin ( with SCDHEC.