The initial model development will be that of a flow through model. It is recommended that the initial model setup be a flow through model to test the connectivity of the stream network and the overall behavior of the initial model setup.
A flow through model consists of the following model characteristics:
1.) No rules of operation are entered into the model
2.) A constant inflow is applied at the upstream ends of the main stem and all tributaries
3.) The reservoirs are set to the top of the conservation pool and are releasing inflow in the lookback period.
4.) The routing is set to null routing.
Once the results of the flow through model verify the connectivity and behavior of the model, additional inflow points with correct inflows, updated rules of operation, updated lookback values, and updated routing information can be incorporated.
Step 1: Create a New Directory
For this example, I created a new folder on my local drive titled, "building a ResSim model".
Stream alignments can be imported from a GIS shapefile, but for this example, the alignment will be drawn in. The stream is drawn first and then the reservoirs and computations points are added. Streams and reservoirs are drawn from upstream to downstream.
In this schematic, there is a main stream with a single reservoir. There are tributaries coming in to the main stream both upstream and downstream of the reservoir. I added the computation points named point 1 and point 2.
Step 4: Create and Save Configuration
Go to Watershed > Configuration Editor. The name given to the configuration is "sample build". The time step is 1 hour.
With the Watershed Setup completed, the Reservoir Network is then developed. In the Reservoir Network, the physical and operational data is input.
Step 5: Create the Reservoir and Dam Physical Data
Select the Reservoir Network module. Create a new network.
I first look at the flow into the reservoir (Junction CP1). This inflow should be 1,000 cfs since I have 500 cfs coming in at Junction 6 and Junction 7.
The junction, "Point 1", should have a flow a 1,000 cfs since that is being passed from the dam and there are no local inflows between the dam and "Point 1".
The junction, "Point 2", will have a local inflow of 500 cfs from the downstream tributary giving a total flow of 1,500 cfs when combined with the outflow from the dam.
At this point, we should feel comfortable that the model connectivity seems correct and that the behavior is what we would expect. New inflow locations, new operations sets with rules, and new routing parameters can be added.
To show a simple example, the flow through operation set will be duplicated and re-named max release. In this operation set, a maximum release rule of 750 cfs will be added.
The alternative named flow thru will be saved as "max rel". The operations set under the operations tab will be changed to max release.
Since the dates of our simulation are staying the same, we can add the max rel alternative to Jan-Feb 2015 sim and uncheck flow thru.
One final point is that this model was developed in English units. By selecting View > Unit System in the simulation module, the results can be viewed in SI.