MIKE URBAN: Storm Water Tool Box

Urban stormwater flood modelling can be carried out using a 1D/1D or a 1D/2D approach. The 1D/1D (MIKE URBAN) approach has a simplified representation of the overland surface hydraulics compared to the 1D/2D (MIKE FLOOD - URBAN) approach.

In recent years coupled 1D-2D modelling applications have been used in urban stormwater analysis. The advantage of the 1D/2D is that it is faster to setup the model and it provides a more realistic modelling of the surface flow. Model run-times are however generally long (hours to days), which makes the design and testing of stormwater improvements difficult and time consuming.

The advantage of the 1D/1D approach is that the simulation time is considerable faster than the 1D/2D model and is therefore more suitable for detailed design option runs. However the work involved setting up the model is a more tedious process than setting up the 1D/2D model.

A new set of storm water modeling tools has been developed which specifically address some aspects of building a 1D/1D stormwater model. These bundled tools are called MIKE URBAN – Storm Water Toolbox. The tools have been developed by DHI with input from Aravinda Senaratna and Paul Ollett at Technical Services at Gold Coast City Council.

The MIKE URBAN Stormwater Toolbox focuses on building the stormwater model within a 1D framework and following 5 tools have currently been developed:

• Lateral Snapping
• Cross Section Extraction
• Auto Connection of Overland Network to Sewer Network
• Sequential Labelling of Nodes
• Catchment Slope and Length Calculation

1. The lateral snapping tool can be used to move selected nodes in MIKE URBAN and snap them laterally to the lowest DEM value along a lateral snap alignment


Illustration 1: User Tools – Lateral Snap Tool

2. The Cross Section Extraction tool uses cross section alignments drawn in a line feature type layer or ArcGIS shape file to extract cross sections from DEM for MIKE URBAN links directly into the cross section database as well as setting the reference between the link and the extracted cross section ID.


Illustration 2a: User Tools – Cross Section Generation from DEM


Illustration 2b: User Tools – Cross Section alignments for generating CRS from DEM (Yellow lines)


3. When overland flow paths have been digitised and snapped to correct alignment then the overland flow links has to be connected to each other (overland to overland) or connections has to be made between overland flow network and underground network (Overland to Stormwater). The Auto Connection of Overland Network to Sewer tool has been developed in a generic way so that it can be used for many different types of MIKE URBAN modelling projects and not only in storm water 1D/1D modelling projects. The tool can be used for connecting networks by weirs, orifices or storm water inlets (lintels).


Illustration 3: User Tools – Auto Connection of network

4. When an overland flow path or other network is digitised in a MIKE URBAN model then it is often required to provide IDs that are descriptive and logical. The IDs are often made up by street names, type of network, sub-catchment identifier etc, that meets a Councils naming convention. A Sequential Labelling tool has been developed to ease this task.


Illustration 4: User Tools – Sequential Labelling


5. A catchment Slope and Length tool has been developed to provide the slope and length for a catchment in a consistent, documented and reproducible way.


Illustration 5: User Tools – Catchment Slope and Length


Download the MIKE URBAN Storm Water Tools here.

More information:
Morten Kjølby (DHI Australia), mjk@dhigroup.com