Calite model is an interactive screening model planned and managed by the state water project (SWP) and the Central Valley Project (CVP) in California. It simulates the hydrology of the Central Valley, reservoir operation and delivery allocation decisions to SWP and CVP, delta salinity response to changes in river flow and outlet, and resident ecosystem index. The power of filtering models like callite is the ability to quickly simulate system operations and merge changes relatively easily. The current version of calite simulates the operation of the system on a monthly basis. On the latest modeling computer, it takes about 6 minutes (compared with 30 minutes of calsim), recording a full 82 years of records (water year 1922-2003). Scenarios can be run using a variety of different user specified parameters related to hydrometeorology, requirements, facilities and infrastructure, regulations, and system operations. Through the integrated post-processing tools of the model, we can observe, compare and analyze the results.

MODFLOW is a three-dimensional finite difference groundwater model. It uses modular structure, which makes it easy to modify to adapt to specific application code. Modflow-2000 simulates stable and unsteady flow in irregular flow systems. Aquifers can be closed or unclosed, or a combination of the two, flowing under external pressure, such as flowing to wells, surface recharge, evaporation, flowing to drainage channels, and flowing through riverbed. In addition to simulating groundwater flow, some related functions are extended, such as sediment transport.

GSFLOW The model is developed by the U.S. Geological Survey to simulate the interaction between surface water and groundwater. The model considers the relationship between meteorological conditions, surface runoff, groundwater runoff and the interaction between surface water and groundwater. It is coupled with the rainfall runoff simulation system PRMs and the three-dimensional finite difference model modflow-2005. The model is suitable for the simulation of non spatial and temporal scales In order to evaluate the impacts of land use change, climate change and groundwater exploitation on surface hydrological process and underground hydrological process.

HEC-HMS model is a watershed flood simulation system developed by the hydrological engineering center of the US Army Corps of engineers. It is a semi Distributed Rainfall Runoff Model with physical concept. According to the formation process of rainfall runoff, it is divided into four calculation parts: net rainfall process, direct runoff process, base flow and river confluence, which are mainly used to simulate runoff process in tree basin.