Solutions to Global Challenges

Sustainable Stormwater Management

Efficiently drain surface water while minimising pollution and its impact on water quality with smart, sustainable solutions to control and treat stormwater.

The issue

Urban landscapes continue to expand in the midst of a changing climate. Growing populations, development and densification combined with more frequent severe weather events is overwhelming traditional drainage systems. In cities with mostly hard surfaces, the pollution content in runoff from traffic, building materials and air pollution is threatening water quality in open waters.

Why it matters

To transform a city from a funnel into a sponge, the harvesting of stormwater within its water cycle should be considered for long-term, resilient water balance and reuse. Through vegetation, storage and infiltration, sustainable urban drainage systems (SuDS) or low impact development (LID) rely on natural processes to absorb, filter and break down pollutant substances to protect receiving waters and their biological environment from hazardous substances.

How we can help

The best way to minimise environmental degradation is to integrate the entire water cycle into your planning process. DHI supports the design and implementation of SuDS and LID for both new and existing developments. Through advanced hydraulic and catchment modelling, comprehensive risk assessments and flood mapping, your city can benefit from reduced runoff and improved water quality, efficiency and resilience to climate change.

Integrated solutions

Here are some ways DHI can help city planners, water utilities, municipalities and urban developers revitalise infrastructure and receiving waters for greener cities. 

Increase the efficiency of your Stormwater Management System

To address capacity concerns, DHI runs network simulations with existing or planned components such as pumps, weirs or valves in MIKE URBAN+ under real-time conditions. This insight helps improve the design and assessment of water quality and treatment options in soakaways, secure approval for new developments and has enabled clients to postpone or reduce drainage capacity investments. Bio-retention cells, rain gardens, green rooftops, rain barrels, vegetative swales and porous pavement can also be evaluated with MIKE ECO Lab and the MIKE URBAN+ stormwater quality module.

Future proof your drainage system with integrated catchment modelling

Urban drainage systems are in transition from functioning simply for transport to becoming an important element of urban flood protection measures. Therefore, urban drainage network planning must be future proof taking into account the entire urban water cycle, demographic processes and climate change. DHI supports city planners in identifying storm water storage areas by coupling 1D and 2D urban collection system models, river system and floodplains within MIKE URBAN+ to simulate catchments based on their actual spatial geometry and corresponding hydrological parameters.

Incorporate green solutions into your existing drainage network

Flood map results (such as water depths, flow paths and duration) form the basis for establishing a surface runoff strategy for existing developments. When considering potential green solutions, MIKE URBAN+ can be used to accurately represent any combination of LID controls to determine their effectiveness in managing stormwater and reducing combined sewer overflows. MIKE ECO Lab further supports this analysis in its ability to simulate the fate of bacteria and pollutants in your network and offering a glimpse at how they can be reduced with green infrastructure.

Improve water quality and better manage major sources of pollution

Green infrastructure improves water quality by removing contaminents and decreasing the amount of stormwater that reaches waterways. Through a collaborative design process, DHI can implement a sustainable stormwater management program to better manage pollutants. Terrain models and hydraulic assessments using MIKE URBAN+ and MIKE ECO Lab offer insight into the pollutant reducing effectiveness of green infrastructure and where to establish wetlands for nutrient retention. Furthermore, satellite-based water quality monitoring is used to assess the effectiveness of green infrastructure initiatives over time to understand both the current and historic state and condition of water quality and its variability.

Optimise the master planning process for new developments

When planning new developments, developers need to know which areas are safe to develop and which should be avoided – from a pluvial flood perspective. DHI can conduct a hydraulic and water quality assessment of areas being considered using terrain models and the stormwater quality module in MIKE URBAN+. These models can also determine affordable, yet effective solutions to reduce the impact of heavy rain and build-up of surface pollutants. Vegetative swales and retention ponds in SuDS, LID and water-sensitive urban design (WSUD) can be simulated to investigate their flood reducing effect. Plus, this information supports landscape architects in assessing how various natural elements may be placed.

Ensure your urban infrastructure can adapt to climate change

At DHI, we have access to the latest regional climate model results. By applying bias correction and statistical downscaling, these climate models can simulate an ensemble of future extreme rainfall events. When applied in conjunction with risk assessments and flood maps based on advanced MIKE URBAN+ and MIKE ECO Lab hydraulic and water quality models, we can evaluate the impact of climate change on your pluvial flood situation. Spatially distributed hydrological modelling can further evaluate the effects of future climatic and urban developments on stormwater runoff. Satellite-based urban mapping solutions provide ideal reference information on the amount, location and type of impervious surfaces as input for these models.

Client successes



How to manage urban stormwater quality in three steps

To guide the selection of efficient stormwater management options to reduce the impact of polluted stormwater runoff to water quality in receiving bodies, it’s necessary to characterise the catchment and untreated runoff quality both spatially and temporally. A spatial analysis and planning system can identify critical source areas for pollutant load reduction, prioritise mitigation based on contaminant influence on in-stream ecological health, and provide mitigation options through best practice stormwater management systems.

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Featured training


Sustainable stormwater modelling in cities using MIKE URBAN+

Making cities more sustainable involves managing a larger portion of the stormwater locally through the implementation of green solutions, surface storage and controlled surface flooding often combined with rehabilitation and an extension of existing infrastructure capacity. Register for this free 45-minute webinar to learn how MIKE URBAN+ can support these initiatives through  various stormwater modelling options.

20 Aug 2020 | 7:00-7:45 and 13:00-13:45 UTC | Register


Getting started with urban flood modelling

Take advantage of this free, modular online course for step-by-step introductions on the basic functions of MIKE URBAN+ 2D Overland Flow (MIKE URBAN+ 2D). Learn how to couple a 1D network to a 2D overland model and run your very first simulation in MIKE URBAN+ 2D!

Available anytime | Register


Getting started with urban drainage modelling

Receive easy to follow introductions on the basic functions of MIKE URBAN+ Collection Systems (MU+ CS). Upon completion of this free, online course you will be able to set up and run your first model in MIKE URBAN+ CS and be ready to take our more advanced MIKE URBAN+ CS courses.

Available anytime | Register

Tell us about your project

Book a complimentary 30-minute consultation with a stormwater expert to discuss the specific needs of your project.

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Request a consultation or more information

DHI is here to provide you with more information, answer any questions you may have, and discuss the best services and technological solutions to help tackle your stormwater management challenges.

DHI are the first people you should call when you have a tough challenge to solve in a water environment – be it a river, a reservoir, an ocean, a coastline, within a city or a factory. Our knowledge of water environments is second-to-none. It represents more than 50 years of dedicated research and real-life experience from more than 140 countries. We strive to make this knowledge globally accessible to clients and partners by channelling it through our local teams and unique software. Our world is water. So whether you need to save water, share it fairly, improve its quality, quantify its impact or manage its flow, we can help. Our knowledge, combined with our team’s expertise and the power of our technology, holds the key to unlocking the right solution.