As the climate changes and the number and frequency of rainfall events increases, so does the need for intelligent rainwater management solutions. This White Paper presents insight into lessons learned from Danish stakeholders within rainwater management and Sustainable Urban Drainage Systems (SUDS).

From Climate Adaption to Green Urban Development

Many factors such as population growth, increased pollution of available drinking water, floodings and more frequent periods of droughts encourage an optimised use of our rainwater. In addition, there is an increased focus on reducing the urban heat island effect by cooling the cities locally and on reducing pollution of surface water, securing sufficient drinking water supply and building cities that are attractive for people to live in.

According to the projections from the UN’s Intergovernmental Panel on Climate Change, many countries will experience a change in precipitation over the coming years with more frequent rain of high intensity and longer periods of dry weather. When combining these projections with the fact that many cities are covered with extensive areas of impermeable surfaces, the need for infiltrating or delaying rainwater at the source becomes even more urgent to reduce the risk of flooding.

Using Rainwater as a Resourse

In this white paper, we present the various possibilities of using rainwater as a resource as opposed to considering it as something that simply needs to be hidden in sewers. The aim of using rainwater as a resource is partly to reduce the risk of flooding by optimising the rainwater management and partly to contribute to creating more green and liveable cities.

The key is to have the right tools and models to ensure the right prioritisation of efforts and sufficient designing of the various rainwater management solutions as well as involving the right stakeholders at the right time throughout the process. Several benefits can be achieved by using rainwater to help cities keep a sustainable water balance through various treatment technologies. These ensure proper treatment of rainwater to allow for infiltration to the groundwater aquifers or discharge into the local water environments such as lakes or streams. Finally, in areas suffering from water scarcity, local rainwater harvesting and recycling can be a valuable source of non-potable water which can be used for watering plants, flushing toilets or washing clothes instead of using the precious drinking water.

Partners featured in this publication



Ramboll is a leading multidisciplinary independent consultancy company Our 1,500 experts in energy provide our customers with cost-effective energy and climate solutions that meet today’s standards. We are among the leading consultants in the world within important energy, climate mitigation and climate adaption services: •Sustainable development of liveable cities •Least cost energy planning and strategies •District heating and cooling •Combined heat and power •Heat pumps •Waste to energy •Large scale solar water heating •Thermal storage tanks and storage pits •Wind farm infrastructure on and off shore •Power grids •Integrated smart energy system •Climate strategies •Waste management •Biogas •Exploration of oil and gas •Natural gas transmission and distribution •Natural gas storage Our multidisciplinary approach also includes other renewable sources, hydro power, geothermal energy, energy efficiency in building and industry and low energy buildings. Furthermore, Ramboll’s experts address global water and climate challenges by working across the water cycle from water resources and supply, processing and treatment, to sewerage and discharge. Working with municipalities, utilities, and industrial clients we draw on multidisciplinary expertise to create innovative, sustainable and liveable solutions for our customers and society. Our more than 700 water consultants – mainly engineers, hydraulic specialists, water consultants and landscape architects, but also economists, legal advisors and management consultants – work with water projects on a global scale with more than 50 years of proven experience. Discover more in this video about Ramboll's global water practice. To learn more about Urban Energy Solutions, see Rambolls blog