Rainfall Overlay tutorial

Getting Started

1. Open the Tygron Engine, logon with user name and password and open the project Inun Test NL
2. Download and unpack the content of this zip-file on your desktop: [1]

Editing terrain: importing surface water

First we add water to the terrain model of our project:

1. Go to Terrain in the ribbon and select Import GeoJSON file
2. Press Select File and import the file openwater.geojson from the tutorial
3. Select Water from the Import as Terrain Type: selection menu

Press Send. You have added the canals of our water system!

Adding a Rainfall Overlay

1. Go to Overlays, in the GeoData ribbon and select Add Rainfall. The rainfall indicator appears on the left-side-panel
2. Open the Rain Overlay Wizzard by clicking on the Configuration Wizard button in the right-side-panel

The Rainfall Overlay Wizard will appear:

Step 1: defining the weather

Press Next to proceed to the Weather panel, here the user can define rainfall and evaporation input. Change all numbers and the according to this picture: File:RFO Tutorial Weather.png

By this setting you have defined a rainfall event:

1. Of two peaks in 120 minutes
2. With a total rainfall amount of 100mm
3. With a dry period after rainfall of 120 minutes, so a total simulation time of 4 hours

Reference evapotranspiration will be assumed on 1.5mm/day

Step 2: setup of the water system

Press next to proceed to the introduction screen Setup Water System

Step 2.1: adding water level areas

Press next to the screen for importing water areas. A water level area is an area with a spatially uniform water level varying in time. Variation is caused by rainfall + evaporation on the surface water, inflow from sewer areas, inflow from the surface and groundwater inflow.

There are three options:

• Import Water Areas: allows you to import a set of water level areas from an external dataset
• Generate Water Areas: allows you to define 1 water level area for your project area
• Do Nothing: the surface water system effectively has infinite storage

Press Import Water Areas and press Select File. Browse to the file: waterlevelareas.geojson. Set the following:

1. Set name based on attribute, and select the NAME attribute from the geojson file.
2. Import the OUTLET attribute and assign it to the OUTLET key. Here a pump capacity (m3/s) is specified. In water areas with the pump capacity defined, water will be extracted with the pump capacity. Extracted water via the pump is assumed to be discharging outside the project domain.
3. Import the WATER_LEVEL attribute and assign it to the WATER_LEVEL key. Here the initial water level in the water area is defined in m + reference (being NAP in the Netherlands)

Press send: you have now successfully defined your water areas!

Step 2.2: initial groundwater level

In step 2.2, you can specify ground water levels. By default, ground water levels are assumed to be the same as the water level in the water level area (see previous section). Alternatively, the user can specify pre-defined initial groundwater levels (GHG,GLG and GVG for the Netherlands) or a GeoTiff with ground water levels in m + reference (NAP in The Netherlands).

We will not do that as part of the tutorial and press Next

Step 2.3: adding sewer areas

Sewer districts are represented by areas which have one storage value (mm), uniform in space. Sewer storage will vary in time by sewer inflow from connected buildings (buildings, roads, etc), pumped outflow to a WWTP and sewer overflow to surface water.

Upload your GeoJson file by selecting Import Sewers in the Sewers screen.

Press Select File, browse to the file: sewerdistricts.geojson. Set the following:

1. Set name based on attribute, and select the NAME attribute from the geojson file.
2. Import the SEWER_PUMP_CAPACITY attribute and assign it to the SEWER_PUMP_SPEED key. Here a pump capacity (m3/s) is specified. In water areas with the pump capacity defined, water will be extracted from the sewer district with the pump-rate. Extracted water via the pump is assumed to be discharging outside the project domain.
3. Import the SEWER_STORAGE attribute and assign it to the SEWER_STORAGE key. This is the sewer storage in meters

Press send: you have now successfully defined your sewer districts!

Step 2.4: adding hydraulic structures

Currently one can import the following hydraulic structure:

• Weirs, connecting different water areas. Flow between two water areas is computed with the weir formula, using the water level of the connected water areas(1).
• Culverts, connecting two water areas. Flow between two water areas is assumed to be equal to a fixed flow capacity(1).
• Pumps, connecting two water areas. Flow between two water areas is assumed to be equal to the pump capacity(2).

(1) In cases in the Netherlands: deze kunstwerken zijn typisch peilscheidende duikers en stuwen.

(2) In cases in the Netherlands: deze pompen zijn typisch voor onderbemalingen en zoetwatervoorziening in droge tijden.