Scope and Purpose
The Chesapeake Bay Program integrated models include simulations of the airshed, watershed, estuary, living resources, and climate change. These integrated models assess effects of current and proposed watershed management on changes in nutrient and sediment loads delivered to the Bay, and the effect those changing loads have on water quality and living resources. The CBP Models assist CBP decision-makers in estimating the collective actions needed to achieve State and Federal water quality standards necessary to restore the Bay.
The Modeling Workgroup has a responsibility to the Chesapeake Bay Program Partnership to provide state-of-the-art decision-support modeling tools that are built through community and participatory principles. The responsible planning and management of resources to provide the best available decision-support modeling tools requires the Modeling Workgroup members and participants to adhere to the core values of:
- Integration - Integration of most recent science and knowledge in air, watershed, and coastal waters to support ecosystem modeling for restoration decision making.
- Innovation - Embracing creativity and encouraging improvement in the development and support of transparent and robust modeling tools.
- Independence – Making modeling decisions on the basis of best available evidence and using the most appropriate methods to produce, run, and interpret models, independent of policy considerations.
- Inclusiveness - Commitment to an open and transparent process and the engagement of relevant partners, that results in strengthening the Partnership’s decision making tools.
Overall CBP Model Framework
The CBP model framework is designed to address questions of how Chesapeake Bay water quality will respond to changes in watershed and airshed management actions. In the first step of model scenario development, scenario management actions are interpreted by several models, including the Land Use Change Model, the Airshed Model, and Scenario Builder to produce input to the Watershed Model, as shown in the figure below. The CBP Land Use Change Model, predicts changes in land use, sewerage, and septic systems given changes in land use policy. The Airshed Model, a national application of Community Multiscale Air Quality Model (CMAQ), predicts changes in deposition of inorganic nitrogen due to changes in emissions. The Scenario Builder software combines the output of these models with other data sources, such as the US Census of Agriculture, to generate inputs to the Watershed Model. The Phase 5.3 Watershed Model predicts the loads of nitrogen, phosphorus, and sediment that result from the given inputs.The estuarine Water Quality and Sediment Transport Model (WQSTM) (also known as the Chesapeake Bay Model) predicts changes in Bay water quality due to the changes in input loads provided by the Watershed Model. As a final step, a water quality standard analysis system examines model estimates of DO, chlorophyll, and water clarity to assess in time and space the attainment of the Bay living resource-based water quality standards.
Additional information can be found at:
Projects and Resources
Phase 6 WSM Documentation
The Final Chesapeake Bay Program Partnership Phase 6 CAST and Watershed Model documentation is posted as it becomes available. The documentation is for the time-averaged Watershed Model. CAST is the same as the Model. Creating and running scenarios in CAST is simply using an on-line interface to the Model. The documentation for the Model is the documentation for CAST. Due to the length of the documentation, it is divided into sections. Click on the links below to read through the different portions of the documentation. For more information, please vist CAST model documentation.
- Average Loads
Appendix 2A:Agricultural Loading Rates
- Terrestrial Inputs-coming soon
Appendix 4A: Sensitivity analysis of the HSPF AgChem Model
Appendix 4B: Sensitivity analysis for all land uses
- Land Use-coming soon
- Best Management Practices
Appendix 6A: BMP Expert Panel Protocol
Appendix 6B Order of Load Source Change Credit
- Land to Water
- Direct Loads - coming soon
- Stream to River
Appendix 9A: lternate Stream to River Methods
Appendix 9B: Excluded Reservoir Catchments
- River to Bay and Temporal Simulation
Appendix 10A: Temporal Simulation - coming soon
Appendix 10B: Temporal Simulation - coming soon
Appendix 10C: Temporal Simulation - coming soon
- Physical Setting
Appendix 11A: List of Segments
- Applications - coming soon
- Reviews - coming soon
- References - coming soon
The Chesapeake Bay TMDL 2017 Midpoint Assessment
Phase 6 WQSTM Peer Review
This project page is the repository for documents and files related to the peer review of the Phase 6 Water Quality and Sediment Transport Model (WQSTM). Please email Kyle Hinson (firstname.lastname@example.org) with any questions you may have.
All documentation for the Phase 6 WQSTM can be found in the Draft 2017 documentation and its appendices. Information on key scenarios can also be found in the Phase 6 Key Scenarios pdf file.
Further attachments contain all the presentations that were presented for the STAC peer review.
Phase 6 WQSTM Peer Review
This section contains resources and publications including prior reviews that may be employed in reviewing the Phase 6 Water Quality and Sediment Transport Model (WQSTM).
New web page summarizes the priorities and identifies lead researchers for each effort. The descriptions are brief with links to more detailed workplans.
Chesapeake Bay Bathymetric Volumes
CMAQ Peer Reviews
CMAQ Review Process: During the past three years, CMAS, in collaboration with EPA scientists, has organized two CMAQ review panel meetings etc. The first CMAQ review meeting was held during December 2003. The second meeting was held during May 2005. The review process usually starts by inviting a number of key scientists to participate in the process. The scientists are selected based on their expertise in accordance with the focus of the review session. After reviewing numerous reports and articles and completing their meeting in Research Triangle Park, North Carolina, the review panel prepares a comprehensive report on their findings and recommendations. EPA then responds to the comments of the reviewers. Final review reports are posted below.
First Review (December, 2003)
Congestion Mitigation and Air Quality (CMAQ) Model - Third Review (February, 2007)
Chesapeake Bay Models