This graphical interface to the Phase 7 Watershed Model inputs is provided by the Chesapeake Bay Program to facilitate review of the data by the Partnership. The Chesapeake Bay Program intends for this interface to facilitate transparency in the Watershed Model and offer a common, public platform for reviewing data. The visualizations provide the Chesapeake Bay Program partners with information on Phase 7 inputs to the draft Watershed Model. The input review process is intended to help partners, in coordination with their jurisdictional subject matter experts, identify potential concerns in advance of the formal review period, enabling more efficient issue resolution once loads are released. This process is separate from the formal review process and does not count toward the review timeline.

Several methodologies used to develop draft Phase 7 Model inputs were revised from Phase 6 through workgroup approval, so input datasets may not be directly comparable across Model phases. Data represent inputs for the model calibration. The Phase 6 version of the model, completed in October 2017, includes datasets from 1985-2013. The first Phase 7 calibration started in June 2026 and includes datasets from 1985-2024.

Comments on these visualizations will be reviewed until February 12, 2027. To streamline communication and avoid duplicate feedback, jurisdictions should designate a single point of contact for comments and questions. Workgroups are encouraged to coordinate internally with members on shared concerns before submitting feedback to avoid duplicate questions. For questions and comments related to Wastewater, contact pointsource@chesapeakebay.net, and for all other input datasets, contact non-pointsource@chesapeakebay.net.

Data are updated when the new versions are released, and as new data become available. Functionality upgrades are made on a rolling basis in response to comments and requests from users.

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