FDM (Fischer Delta Model)
Criterion | Explanation |
General Description | The Fischer Delta Model (FDM) is a deterministic hydrodynamic and salt transport model developed for the Sacramento-San Joaquin Delta. This model simulates flow and salinity variations due to changes in channel geometry, hydrologic variability, and operation of control structures in an estuarial environment. |
Model Domain | There are several versions of the FDM, with each version developed to meet special needs of different projects. The model area covered is different in each version. |
Developer | Dr. Hugo B. Fischer, beginning in 1976 |
Hardware computing requirements | The model runs on Windows-based machines. |
Code language | FORTRAN |
Original application | The Fischer Delta Model was developed to simulate hydrodynamics and salinity distribution in the Sacramento-San Joaquin Delta. |
Public/proprietary and cost | The model is proprietary. Cost is not reported. |
Physically or empirically based | Physically based |
Mathematical methods used | The Fischer Delta Model consists of two linked models: a hydrodynamic model and a water quality model. The hydrodynamic model (DELFLO) utilizes the fixed grid method of characteristics to simulate the hydrodynamics of the Delta. The water quality model (DELSAL) uses the Lagrangian method, in which the motions of parcels of water are followed through the Delta. |
Input data requirements | Input data for the Delta is well-parameterized and readily available from public sources. Input includes data on Delta channel geometry, friction factors (Manning's n), river inflow data (flow rate and salinity), diversion rates, agricultural return flows applied at locations throughout the Delta, precipitation based on historical records, and tidal elevation at model boundaries. |
Outputs | DELFLO provides surface-water elevation and flow; DELSAL provides total dissolved solids, chloride or other conservative constituent concentrations. |
Pre-processing and post-processing tools | Unknown |
Representation of uncertainty | Uncertainty is not represented. |
Prevalence | Several versions of the model were developed to meet special needs of different projects. |
Ease of use for public entities | Because the model is proprietary and not available to the public, it can only be used by the model developers and their consultants. |
Ease of obtaining information and availability of technical support | The model is not supported for public use. |
Source code availability | The model is proprietary. |
Status of model development | The consulting firm Flow Science maintains the Fischer Delta Model (FDM). Flow Science is currently working on Version 10.0, which will revise the channel geometries of the original model to incorporate information from new field surveys. |
Challenges in integration | Because the model is proprietary and not available to the public, it can only be used by the model developers. |