The U.S. Army Corps of Engineers (USACE) is pleased to announce the release of the Antecedent Precipitation Tool (APT), version 3.0. The APT v3.0 expands upon previous functionality by incorporating streamflow data alongside precipitation analysis, providing a more comprehensive description of hydrologic and climatic conditions across the United States and its territories. Driven by research conducted by the U.S. Army Engineer Research and Development Center (ERDC), APT v3.0 incorporates streamflow observations from the USGS and modeled streamflow conditions from the National Water Model, with outputs available in KMZ and PDF formats to support streamlined visualization and reporting.
Along with the release of the new version of this tool, USACE is also announcing the availability an updated user guide for APT v3. Developed by ERDC, this guide serves as both a practical reference for users and the technical documentation for the tool, detailing inputs, outputs, analytical methods, common issues, and troubleshooting tips.
The public can access the tool and accompanying user guide at the following links:
Download APT v3: https://github.com/erdc/Antecedent-Precipitation-Tool/releases/latest
User Guide & Technical Note: http://dx.doi.org/10.21079/11681/49835
The APT may be used to accelerate USACE decision-making time by automating and augmenting the requirement of the Regional Supplements to the Corps of Engineers Wetland Delineation Manual (Regional Supplements) when evaluating precipitation and other climatic variables associated with 1) difficult wetland situations (see Chapter 5 of the Regional Supplements) or 2) the assessment of certain wetland hydrology indicators (e.g., saturation or inundation visible on aerial imagery or dry-season water table). The APT also has utility in evaluating precipitation normalcy for site visits, when reviewing wetland determination data forms, or when collecting, observing, or evaluating streamflow duration information or data.
The APT continues to be one of the most frequently used tools by USACE, its federal and state partners, Tribes, and the public in USACE Clean Water Act decision-making. We encourage you to explore the new features and welcome your feedback. Please submit any questions, comments, or suggestions to the following inbox: APT-Report-Issue@usace.army.mil.