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DSM2

DSM2 models, data, and other resources. The links are in chronological order, with most recent releases at the top. * The Delta Simulation Model II (DSM2) is a is a river, estuary, and land modeling system. It is a one-dimensional mathematical model for dynamic simulation of one-dimensional hydrodynamics, water quality and particle tracking in a network of riverine or estuarine channels. DSM2 can calculate stages, flows, velocities, mass transport processes for conservative and non-conservative constituents including salts, water temperature, dissolved oxygen, and trihalomethane formation potential, and transport of individual particles. DSM2 thus provides a powerful simulation package for analysis of complex hydrodynamic, water quality, and ecological conditions in riverine and estuarine systems. * DSM2 is licensed under the GNU General Public License. This means it can be copied, distributed, and modified freely, but you may not restrict others in their ability to copy, distribute, and modify it. See GNU General Public License for more details. *For more information: https://water.ca.gov/Library/Modeling-and-Analysis/Bay-Delta-Region-models-and-tools/Delta-Simulation-Model-II * **The latest version of the DSM2 executables is v8.5.0. The latest version of the model input is DSM2 Input 2026-06-29 historical update. This version of the input was developed with DSM2 v8.5.0.** Department of Water Resources (DWR) makes no warranties or guarantees -- either expressed or implied -- as to the completeness, accuracy, or correctness of the data herein (subject data), including any associated metadata. DWR neither accepts nor assumes liability arising from or for any incorrect, incomplete, or misleading subject data or reproductions of the subject data. Users are prohibited from any commercial, no-free resale, or redistribution without explicit written permission from DWR. Users should acknowledge DWR as the source used in the creation of any reports, publications, new data sets, derived products, or services resulting from the use of the subject data. DWR expressly disclaims any responsibility to defend or indemnify users against claims of others based on users' copying reliance, distribution, or other use of any of the subject data.

Data files

Data title and descriptionAccess dataFile detailsLast updated

DSM2 v8.4.1

DSM2 models, data, and other resources. The links are in chronological order, with most recent releases at the top. * The Delta Simulation Model II (DSM2) is a is a river, estuary, and land modeling system. It is a one-dimensional mathematical model for dynamic simulation of one-dimensional hydrodynamics, water quality and particle tracking in a network of riverine or estuarine channels. DSM2 can calculate stages, flows, velocities, mass transport processes for conservative and non-conservative constituents including salts, water temperature, dissolved oxygen, and trihalomethane formation potential, and transport of individual particles. DSM2 thus provides a powerful simulation package for analysis of complex hydrodynamic, water quality, and ecological conditions in riverine and estuarine systems. * DSM2 is licensed under the GNU General Public License. This means it can be copied, distributed, and modified freely, but you may not restrict others in their ability to copy, distribute, and modify it. See GNU General Public License for more details. *For more information: https://water.ca.gov/Library/Modeling-and-Analysis/Bay-Delta-Region-models-and-tools/Delta-Simulation-Model-II * **The latest version of the DSM2 executables is v8.5.0. The latest version of the model input is DSM2 Input 2026-06-29 historical update. This version of the input was developed with DSM2 v8.5.0.** Department of Water Resources (DWR) makes no warranties or guarantees -- either expressed or implied -- as to the completeness, accuracy, or correctness of the data herein (subject data), including any associated metadata. DWR neither accepts nor assumes liability arising from or for any incorrect, incomplete, or misleading subject data or reproductions of the subject data. Users are prohibited from any commercial, no-free resale, or redistribution without explicit written permission from DWR. Users should acknowledge DWR as the source used in the creation of any reports, publications, new data sets, derived products, or services resulting from the use of the subject data. DWR expressly disclaims any responsibility to defend or indemnify users against claims of others based on users' copying reliance, distribution, or other use of any of the subject data.

DownloadZIP
07/18/25

DSM2 2023.01 Historical Update

DSM2 models, data, and other resources. The links are in chronological order, with most recent releases at the top. * The Delta Simulation Model II (DSM2) is a is a river, estuary, and land modeling system. It is a one-dimensional mathematical model for dynamic simulation of one-dimensional hydrodynamics, water quality and particle tracking in a network of riverine or estuarine channels. DSM2 can calculate stages, flows, velocities, mass transport processes for conservative and non-conservative constituents including salts, water temperature, dissolved oxygen, and trihalomethane formation potential, and transport of individual particles. DSM2 thus provides a powerful simulation package for analysis of complex hydrodynamic, water quality, and ecological conditions in riverine and estuarine systems. * DSM2 is licensed under the GNU General Public License. This means it can be copied, distributed, and modified freely, but you may not restrict others in their ability to copy, distribute, and modify it. See GNU General Public License for more details. *For more information: https://water.ca.gov/Library/Modeling-and-Analysis/Bay-Delta-Region-models-and-tools/Delta-Simulation-Model-II * **The latest version of the DSM2 executables is v8.5.0. The latest version of the model input is DSM2 Input 2026-06-29 historical update. This version of the input was developed with DSM2 v8.5.0.** Department of Water Resources (DWR) makes no warranties or guarantees -- either expressed or implied -- as to the completeness, accuracy, or correctness of the data herein (subject data), including any associated metadata. DWR neither accepts nor assumes liability arising from or for any incorrect, incomplete, or misleading subject data or reproductions of the subject data. Users are prohibited from any commercial, no-free resale, or redistribution without explicit written permission from DWR. Users should acknowledge DWR as the source used in the creation of any reports, publications, new data sets, derived products, or services resulting from the use of the subject data. DWR expressly disclaims any responsibility to defend or indemnify users against claims of others based on users' copying reliance, distribution, or other use of any of the subject data.

DownloadZIP
07/18/25

DSM2 2023.01 Historical Update Output

DSM2 models, data, and other resources. The links are in chronological order, with most recent releases at the top. * The Delta Simulation Model II (DSM2) is a is a river, estuary, and land modeling system. It is a one-dimensional mathematical model for dynamic simulation of one-dimensional hydrodynamics, water quality and particle tracking in a network of riverine or estuarine channels. DSM2 can calculate stages, flows, velocities, mass transport processes for conservative and non-conservative constituents including salts, water temperature, dissolved oxygen, and trihalomethane formation potential, and transport of individual particles. DSM2 thus provides a powerful simulation package for analysis of complex hydrodynamic, water quality, and ecological conditions in riverine and estuarine systems. * DSM2 is licensed under the GNU General Public License. This means it can be copied, distributed, and modified freely, but you may not restrict others in their ability to copy, distribute, and modify it. See GNU General Public License for more details. *For more information: https://water.ca.gov/Library/Modeling-and-Analysis/Bay-Delta-Region-models-and-tools/Delta-Simulation-Model-II * **The latest version of the DSM2 executables is v8.5.0. The latest version of the model input is DSM2 Input 2026-06-29 historical update. This version of the input was developed with DSM2 v8.5.0.** Department of Water Resources (DWR) makes no warranties or guarantees -- either expressed or implied -- as to the completeness, accuracy, or correctness of the data herein (subject data), including any associated metadata. DWR neither accepts nor assumes liability arising from or for any incorrect, incomplete, or misleading subject data or reproductions of the subject data. Users are prohibited from any commercial, no-free resale, or redistribution without explicit written permission from DWR. Users should acknowledge DWR as the source used in the creation of any reports, publications, new data sets, derived products, or services resulting from the use of the subject data. DWR expressly disclaims any responsibility to defend or indemnify users against claims of others based on users' copying reliance, distribution, or other use of any of the subject data.

DownloadZIP
07/18/25

DSM2-Hg / Open Water Mercury Program inputs

DSM2 models, data, and other resources. The links are in chronological order, with most recent releases at the top. * The Delta Simulation Model II (DSM2) is a is a river, estuary, and land modeling system. It is a one-dimensional mathematical model for dynamic simulation of one-dimensional hydrodynamics, water quality and particle tracking in a network of riverine or estuarine channels. DSM2 can calculate stages, flows, velocities, mass transport processes for conservative and non-conservative constituents including salts, water temperature, dissolved oxygen, and trihalomethane formation potential, and transport of individual particles. DSM2 thus provides a powerful simulation package for analysis of complex hydrodynamic, water quality, and ecological conditions in riverine and estuarine systems. * DSM2 is licensed under the GNU General Public License. This means it can be copied, distributed, and modified freely, but you may not restrict others in their ability to copy, distribute, and modify it. See GNU General Public License for more details. *For more information: https://water.ca.gov/Library/Modeling-and-Analysis/Bay-Delta-Region-models-and-tools/Delta-Simulation-Model-II * **The latest version of the DSM2 executables is v8.5.0. The latest version of the model input is DSM2 Input 2026-06-29 historical update. This version of the input was developed with DSM2 v8.5.0.** Department of Water Resources (DWR) makes no warranties or guarantees -- either expressed or implied -- as to the completeness, accuracy, or correctness of the data herein (subject data), including any associated metadata. DWR neither accepts nor assumes liability arising from or for any incorrect, incomplete, or misleading subject data or reproductions of the subject data. Users are prohibited from any commercial, no-free resale, or redistribution without explicit written permission from DWR. Users should acknowledge DWR as the source used in the creation of any reports, publications, new data sets, derived products, or services resulting from the use of the subject data. DWR expressly disclaims any responsibility to defend or indemnify users against claims of others based on users' copying reliance, distribution, or other use of any of the subject data.

DownloadZIP
07/18/25

DSM2 2022.01 Historical Update Output

DSM2 models, data, and other resources. The links are in chronological order, with most recent releases at the top. * The Delta Simulation Model II (DSM2) is a is a river, estuary, and land modeling system. It is a one-dimensional mathematical model for dynamic simulation of one-dimensional hydrodynamics, water quality and particle tracking in a network of riverine or estuarine channels. DSM2 can calculate stages, flows, velocities, mass transport processes for conservative and non-conservative constituents including salts, water temperature, dissolved oxygen, and trihalomethane formation potential, and transport of individual particles. DSM2 thus provides a powerful simulation package for analysis of complex hydrodynamic, water quality, and ecological conditions in riverine and estuarine systems. * DSM2 is licensed under the GNU General Public License. This means it can be copied, distributed, and modified freely, but you may not restrict others in their ability to copy, distribute, and modify it. See GNU General Public License for more details. *For more information: https://water.ca.gov/Library/Modeling-and-Analysis/Bay-Delta-Region-models-and-tools/Delta-Simulation-Model-II * **The latest version of the DSM2 executables is v8.5.0. The latest version of the model input is DSM2 Input 2026-06-29 historical update. This version of the input was developed with DSM2 v8.5.0.** Department of Water Resources (DWR) makes no warranties or guarantees -- either expressed or implied -- as to the completeness, accuracy, or correctness of the data herein (subject data), including any associated metadata. DWR neither accepts nor assumes liability arising from or for any incorrect, incomplete, or misleading subject data or reproductions of the subject data. Users are prohibited from any commercial, no-free resale, or redistribution without explicit written permission from DWR. Users should acknowledge DWR as the source used in the creation of any reports, publications, new data sets, derived products, or services resulting from the use of the subject data. DWR expressly disclaims any responsibility to defend or indemnify users against claims of others based on users' copying reliance, distribution, or other use of any of the subject data.

DownloadZIP
07/18/25

DSM2 Source Code (11/12/2013)

DownloadZIP
07/18/25

DSM2 Planning Study Training example studies

DSM2 models, data, and other resources. The links are in chronological order, with most recent releases at the top. * The Delta Simulation Model II (DSM2) is a is a river, estuary, and land modeling system. It is a one-dimensional mathematical model for dynamic simulation of one-dimensional hydrodynamics, water quality and particle tracking in a network of riverine or estuarine channels. DSM2 can calculate stages, flows, velocities, mass transport processes for conservative and non-conservative constituents including salts, water temperature, dissolved oxygen, and trihalomethane formation potential, and transport of individual particles. DSM2 thus provides a powerful simulation package for analysis of complex hydrodynamic, water quality, and ecological conditions in riverine and estuarine systems. * DSM2 is licensed under the GNU General Public License. This means it can be copied, distributed, and modified freely, but you may not restrict others in their ability to copy, distribute, and modify it. See GNU General Public License for more details. *For more information: https://water.ca.gov/Library/Modeling-and-Analysis/Bay-Delta-Region-models-and-tools/Delta-Simulation-Model-II * **The latest version of the DSM2 executables is v8.5.0. The latest version of the model input is DSM2 Input 2026-06-29 historical update. This version of the input was developed with DSM2 v8.5.0.** Department of Water Resources (DWR) makes no warranties or guarantees -- either expressed or implied -- as to the completeness, accuracy, or correctness of the data herein (subject data), including any associated metadata. DWR neither accepts nor assumes liability arising from or for any incorrect, incomplete, or misleading subject data or reproductions of the subject data. Users are prohibited from any commercial, no-free resale, or redistribution without explicit written permission from DWR. Users should acknowledge DWR as the source used in the creation of any reports, publications, new data sets, derived products, or services resulting from the use of the subject data. DWR expressly disclaims any responsibility to defend or indemnify users against claims of others based on users' copying reliance, distribution, or other use of any of the subject data.

DownloadZIP
07/18/25

Supporting files

Data title and descriptionAccess dataFile detailsLast updated

DSM2 Input 2026-06-29 historical update

Version "DSM2 Input 2026-06-29 historical update" is based on version "DSM2 Input 2026-04-16 historical update" (which incorporates the changes from the Monitoring Special Study version of DSM2), and includes the following changes: Some cross-sections in Middle River are notched by adding a narrow "V" shape to the bottom. This is done to help prevent drying up. In the previous version, notching was done to a bottom elevation of approximately -10 feet NAVD88. This release modifies the notching to a bottom elevation of approximately 0 ft NAVD88. The output location file output_stage_calib_mss.inp was modified to include output locations for stations CIS and MHR.

HTML
07/01/26

DSM2 Input 2026-04-16 historical update

Version "DSM2 Input 2026-04-16 historical update" is based on version "DSM2 Input 2025-09-18 historical update" (which incorporates the changes from the Monitoring Special Study version of DSM2), and includes the following changes: The CHANNEL input section in the file channel_std_delta_grid.inp has been modified to work with DSM2 v8.5.0, by including the "dx" field, which specifies a value of the parameter "delta x" separately for each channel. Previously, delta x values have been specified in a file called variable_dx.csv. This file has been removed. The location of the Middle River Barrier has been corrected by adding channel 901 to replace a portion of channel 134. The Middle River barrier has been placed on the upstream side of the node for consistency with the configurations of other barriers. Dispersion factors have been adjusted to improve EC results.

HTML
05/21/26

DSM2 Input 2025-09-18 historical update

HTML
09/20/25

DSM2 Input 2025-07-03 historical update

HTML
07/18/25

DSM2 v8.4.2


12/04/25

DSM2 Input 2025-05-28 historical update

HTML
07/18/25

South Delta Monitoring Special Studies (MSS)

HTML
07/18/25

DSM2 FC.2023.01


07/18/25

DSM2 2022.01 Historical Update

Historical update 2022.01 validated with DSM2 v8.2.2.

HTML
07/18/25

DSM2 v8.3.1

DSM2 v8.3.1 includes a debugging message level implementation to control the amount of debug messages on screen.

HTML
07/18/25

DSM2 v8.2.2

HTML
07/18/25

DSM2 v8.2.1

HTML
07/18/25

DSM2 v8.2.0

DSM2 V8.2.0 employs the daily DCD channel depletions instead of the monthly values produced by DICU as in the previous release.

HTML
07/18/25

DSM2 8.2.0 beta1

DSM2 V8.2.0b1 release applies the daily DCD v1.0 channel depletions.

HTML
07/18/25

2017 historical update


07/03/26

DSM2 Version 8.1.2

APPLICATION/X-MSDOS-PROGRAM
07/18/25

DSM2 Version 8.0.6

APPLICATION/X-MSDOS-PROGRAM
07/18/25

DSM2 Version 8.0.4

APPLICATION/X-MSDOS-PROGRAM
07/18/25

DSM2 version 6 (Archived Version)

DSM2 version 6. Only for archival purposes.

HTML
07/18/25

DSM2 PDF Grid Map, 2002 version

PDF
07/18/25

DSM2 Georeferenced Model Grids

ESRI shapefiles for DSM2 Model Grids. These are not finalized products. Locations in these shapefiles are approximate.

HTML
07/18/25

DSM2 Cross-Section Development Program (CSDP)

HTML
07/18/25

DSM2 Documents

HTML
07/18/25

2009 BDCP Calibration (aka Mini-Calibration)

PDF
07/18/25

Vista - DSM2

Visualization tool for DSM2 output. More information here https://github.com/CADWRDeltaModeling/dsm2-vista

HTML
07/18/25

ECO-PTM

HTML
07/18/25

ECO-PTM Example Studies

These studies are for the hands-on exercises in the DSM2 ECO-PTM Training. The input files included here are only for training purposes. They are not intended to be used for actual studies.

HTML
07/18/25

API endpoint

Dataset Name

Use the query web API to retrieve data with a set of basic parameters. Copy the API endpoint you need to start.

Usage documentation