Rainwater in cities – inspirations from the world
21/03/2022
Rainwater and responsible water management in cities is not only a way to deal with increasingly scarce water resources and an antidote to torrential downpours and flooding. It is also a way to increase the comfort of residents and a key to improving quality of life in cities. Today, we would like to present you with 3 inspiring examples from around the world that should be a signpost for local authorities everywhere.
Why use rainwater?
The world is urbanising at an unprecedented rate. By 2050, the UN estimates that nearly 70% of the world’s population will live in urban areas. While urbanisation has brought us significant benefits, it has also had a detrimental impact on the ecosystem.
This is why modern agglomerations are more and more boldly turning to unusual solutions in the field of rainwater harvesting and transforming concrete deserts into green oases. And all this so that the inhabitants can not only live and work, but also relax in comfortable conditions.
Forest town of Tengah in Singapore
The world leader in urban greening is undoubtedly Singapore. Designers here are increasingly turning to so-called nature-based solutions that effectively mitigate the negative effects of climate change.
A huge futuristic housing project, dubbed by urban planners “Forest Town”, is being built in Tengah, located in the country’s western region and covering an area of 700 hectares. The project’s designers are working on the concept of a smart, sustainable metropolis.
The first housing development to be built within Forest Town was the Plantation District, surrounded by the multi-level Forest Fringe oasis. The district uses, among other things, an urban water harvesting system that aggregates rainwater for irrigation. An automated waste elimination system is also in operation here, which uses high velocity generated by air suction to transport household waste.
In addition to the Plantation District, other unique residential neighbourhoods such as Park, Garden, Brickland and Forest Hill are being developed in parallel.
Willow School in New Jersey
This unique school is located on a 34-hectare plot of land near the centre of Gladstone. The proximity of countryside, beautiful meadows and butterfly gardens are only a part of this unusual project, which aims not only at traditional teaching, but also at shaping a responsible and pro-ecological attitude in the youngest children.
Rainwater is used here, among other things, for flushing toilets and maintaining the surrounding planting, and waste is treated in the most environmentally friendly way possible. Sixty thousand types of grass and perennials have been planted on the school grounds, partly to reduce water consumption, but also to reduce the need to mow and fertilise the area.
Rainwater is collected in a large underground storage tank and then purified and stored in a 2274-litre tank in the basement. After purification, the water is further treated with ozone, so that it looks like pure drinking water. Another tanker with a capacity of 189,500 litres was installed in the new arts building. The school’s water system is constantly monitored, so students can keep track of how much water is actually reused. This state-of-the-art facility is an active learning centre where sustainability is a key element in the children’s relationship with the world of nature.
Green roofs at O’Hare Airport
Chicago’s O’Hare Airport is one of the largest of its kind in the world, with nearly 80 million passengers a year. It is a huge area with impermeable surfaces, which not only increases the energy consumption for air conditioning of airport buildings, but also raises the temperature and increases the so-called urban heat island effect.
The Chicago Department of Aviation therefore decided to create a green roof system and planted vegetation on 12 airport facilities, including the light control centre, car parks, car rental spaces and even the air traffic control tower, a first of its kind in the world.
The design makes it possible to retain 70-90% of rainwater in summer and 25-40% in winter. Vegetation on the roofs also improves thermal insulation, thus reducing heating costs in winter and cooling costs in summer. In addition, vegetation on the roofs absorbs sound waves produced by the aeroplanes. Just a 2.5 cm layer of vegetation on the roof can reduce the noise level entering the building by around 40 decibels!
The project is part of a new vision for the entire city, in which green roofs will be used on a much larger scale. We would also like to encourage such an approach to Polish local governments, declaring at the same time our full readiness to support them in their pro-ecological activities 🙂