Skip to content

FAQ/ Give a water level time series at the downstream end of a river

Can rivers be given downstream water levels over time?

response

It's possible.

Specify a water level time series as the river property.

Figure: Downstream water level setting screen

Click in the river properties [Downstream water level] and enter the water level time series in the dialog that appears.
You can also [import] import data in CSV format by pressing the button in this dialog.
Here is an example of a CSV file that can be imported:

1
2
3
0,0.9058
3600,0.8892
7200,0.8975

The CSV format is as follows.

  • Column A: Time(s)
  • Row B: Water Level (m)

The data is handled as follows:

  • Before the first time in the data, the value of the first time is used.
  • After the last time in the data, the value of the last time is used.
  • Times within a range of data use the values in the data that are linearly interpolated.

If you set the downstream water level, the River Properties [Downstream water level] [(Configured)] displays .
If not specified, [(Not set)] is displayed. If not specified, the downstream end will be a paragraph flow.

The downstream flow rate is determined by the following procedure.
The software employs a staggered grid for the river model. depth[N] is the water depth in cell N and discharge[N+1/2] is the flow rate between cell N and its downstream neighbor N+1. For paragraphs, depth[N] assume paragraphs from to discharge[N+1/2] find . If the downstream water level is specified, depth[N] is given as a boundary condition and is discharge[N-1/2] calculated by the indeterminate flow calculation. In this case, discharge[N+1/2] is discharge[N-1/2] a copy of .


Last update: 2023-03-20