{"id":15646,"date":"2022-11-07T10:18:13","date_gmt":"2022-11-07T09:18:13","guid":{"rendered":"https:\/\/climagruen.com\/posts\/retention-roofs-act-as-urban-sponges\/"},"modified":"2023-05-02T09:35:19","modified_gmt":"2023-05-02T07:35:19","slug":"retention-roofs-act-as-urban-sponges","status":"publish","type":"post","link":"https:\/\/climagruen.com\/en\/posts\/retention-roofs-act-as-urban-sponges\/","title":{"rendered":"Retention roofs act as urban sponges"},"content":{"rendered":"\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"15646\" class=\"elementor elementor-15646 elementor-8226\" data-elementor-post-type=\"post\">\n\t\t\t\t\t\t<section class=\"elementor-section elementor-top-section elementor-element elementor-element-f2cc967 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"f2cc967\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t<div class=\"elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-640f206\" data-id=\"640f206\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-widget-wrap elementor-element-populated\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-8cddbdb elementor-widget elementor-widget-text-editor\" data-id=\"8cddbdb\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\tIn view of rapid urbanisation and climate change, towns and cities worldwide need to manage water-related risks and make changes in the interests of sustainability and resilience. In this case, urban resilience means, in particular, adapting to the climate.\r\n\r\nIn terms of extreme weather events, it will be vital to modify the infrastructure to solve water-based problems, such as shortages or flooding, which chiefly arise due to urbanisation across the world. To do so, there must be fundamental changes in the way urban environments manage water. An international approach to solving this problem is the sponge city philosophy.\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-998e383 elementor-widget elementor-widget-menu-anchor\" data-id=\"998e383\" data-element_type=\"widget\" data-widget_type=\"menu-anchor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"elementor-menu-anchor\" id=\"schwammstadt\"><\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a011b3d elementor-widget elementor-widget-spacer\" data-id=\"a011b3d\" data-element_type=\"widget\" data-widget_type=\"spacer.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"elementor-spacer\">\n\t\t\t<div class=\"elementor-spacer-inner\"><\/div>\n\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-3576eb5 elementor-widget elementor-widget-heading\" data-id=\"3576eb5\" data-element_type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">The sponge city philosophy<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-dd93997 elementor-widget elementor-widget-text-editor\" data-id=\"dd93997\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p>The sponge city philosophy is an urban planning approach whose core aim is to restore the natural water cycle in urban areas. Its goal is to enhance the infiltration, evapotranspiration, collection and reuse of rainwater in towns and cities.<\/p>\n<p>The sponge city\u2019s underlying concept is to view rainwater as a valuable resource and to leave it in its natural cycle for the most part. The idea is for the city to absorb and store rainwater like a sponge and provide access to it locally where required. Which entails the following benefits:<\/p>\n<ul>\n<li>Local evaporation and infiltration of the rainwater puts less pressure on the sewers.<\/li>\n<li>Flood damage is decreased through delayed and reduced runoff.<\/li>\n<li>The natural water cycle is encouraged.<\/li>\n<li>Evaporation of the rainwater benefits the urban climate and binds dust.<\/li>\n<li>During dry periods, any rainwater stored can be used for local irrigation of urban green spaces instead of drinking water.<\/li>\n<li>Groundwater recharge is encouraged.<\/li>\n<li>Rainwater is purified via the soil through infiltration.<\/li>\n<\/ul>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-8acfda2 elementor-widget elementor-widget-image\" data-id=\"8acfda2\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<img fetchpriority=\"high\" decoding=\"async\" width=\"800\" height=\"533\" src=\"https:\/\/climagruen.com\/wp-content\/uploads\/2022\/11\/Verdunstung-Stadt-Wasser-1024x682.jpg\" class=\"attachment-large size-large wp-image-8260\" alt=\"\" srcset=\"https:\/\/climagruen.com\/wp-content\/uploads\/2022\/11\/Verdunstung-Stadt-Wasser-1024x682.jpg 1024w, https:\/\/climagruen.com\/wp-content\/uploads\/2022\/11\/Verdunstung-Stadt-Wasser-300x200.jpg 300w, https:\/\/climagruen.com\/wp-content\/uploads\/2022\/11\/Verdunstung-Stadt-Wasser-768x512.jpg 768w, https:\/\/climagruen.com\/wp-content\/uploads\/2022\/11\/Verdunstung-Stadt-Wasser-1536x1024.jpg 1536w, https:\/\/climagruen.com\/wp-content\/uploads\/2022\/11\/Verdunstung-Stadt-Wasser-2048x1365.jpg 2048w\" sizes=\"(max-width: 800px) 100vw, 800px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-11ee656 elementor-widget elementor-widget-heading\" data-id=\"11ee656\" data-element_type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h3 class=\"elementor-heading-title elementor-size-default\">Goals of the sponge city philosophy<\/h3>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-453fba5 elementor-widget elementor-widget-text-editor\" data-id=\"453fba5\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p>The sponge city\u2019s primary goal is to make cities more resilient to climate change by creating an urban water cycle, allowing rainwater to evaporate and infiltrate. In addition to this primary goal, there are five other key ones.<\/p>\n<ol>\n<li><strong>Local water retention<\/strong><br \/>\nOver the past few years, local, heavy rainfall has often caused severe flooding and serious damage. The purpose of the sponge city is to decrease and slow down peak flows. This puts less pressure on urban sewers and cuts the risk of flooding during heavy rainfall drastically.<\/li>\n<li><strong>Improvement in urban water quality<\/strong><br \/>\nDue to the rapid pace of urbanisation, drinking water security in lots of towns and cities is in jeopardy. Which is why reducing water pollution is one of the sponge city\u2019s most important goals. In a sponge city, the rainwater is filtered and cleaned via the soil or the substate on green roofs.<\/li>\n<li><strong>Re-establishing the natural water cycle<\/strong><br \/>\nIn order to re-establish a natural water cycle, local infiltration and evaporation must take place. The evaporation performance of intensive green roofs is much higher than that of extensive ones. Local storage of the rainwater is also one of the sponge city\u2019s most key objectives.<\/li>\n<li><strong>Reducing water consumption<\/strong><br \/>\nDue to the fast growth of urban populations, towns and cities have been confronted with numerous water crises over the past few years. The sponge city concept involves using rainwater in different ways and dispenses with the previous concept of rapidly draining water and retains it as a resource instead.<\/li>\n<li><strong>Improving the urban microclimate<\/strong><br \/>\nOverheating of urban areas is one of the best-known urban climate phenomena. Therefore, improving the urban climate\u00a0through evaporative cooling of various elements of the sponge city is a major goal.<\/li>\n<\/ol>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-2bec658 elementor-widget elementor-widget-image\" data-id=\"2bec658\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<img decoding=\"async\" width=\"800\" height=\"534\" src=\"https:\/\/climagruen.com\/wp-content\/uploads\/2022\/11\/Regen-in-Stadtgebiet-gruen-1024x683.jpg\" class=\"attachment-large size-large wp-image-8252\" alt=\"\" srcset=\"https:\/\/climagruen.com\/wp-content\/uploads\/2022\/11\/Regen-in-Stadtgebiet-gruen-1024x683.jpg 1024w, https:\/\/climagruen.com\/wp-content\/uploads\/2022\/11\/Regen-in-Stadtgebiet-gruen-300x200.jpg 300w, https:\/\/climagruen.com\/wp-content\/uploads\/2022\/11\/Regen-in-Stadtgebiet-gruen-768x512.jpg 768w, https:\/\/climagruen.com\/wp-content\/uploads\/2022\/11\/Regen-in-Stadtgebiet-gruen-1536x1024.jpg 1536w, https:\/\/climagruen.com\/wp-content\/uploads\/2022\/11\/Regen-in-Stadtgebiet-gruen-2048x1366.jpg 2048w\" sizes=\"(max-width: 800px) 100vw, 800px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-ed0206c elementor-widget elementor-widget-menu-anchor\" data-id=\"ed0206c\" data-element_type=\"widget\" data-widget_type=\"menu-anchor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"elementor-menu-anchor\" id=\"blaugruen\"><\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-32ae50a elementor-widget elementor-widget-spacer\" data-id=\"32ae50a\" data-element_type=\"widget\" data-widget_type=\"spacer.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"elementor-spacer\">\n\t\t\t<div class=\"elementor-spacer-inner\"><\/div>\n\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a92cc74 elementor-widget elementor-widget-heading\" data-id=\"a92cc74\" data-element_type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">Blue\/green infrastructure in the sponge city<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-c90d856 elementor-widget elementor-widget-text-editor\" data-id=\"c90d856\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p>A growing number of publications shows that solutions based on nature, in particular enhancing the blue\/green infrastructure, are sustainable methods of creating water-resilient towns and cities.<\/p>\n<p>Blue\/green infrastructure is gaining recognition as a complementary method of urban flood risk management, alongside the grey infrastructure (sewers) in many towns and cities. This is because it provides a whole host of benefits alongside its main one, which is to provide flood protection. The advantages include improving water and air quality, increasing local climate resilience, maintaining the natural water cycle, boosting urban dwellers\u2019 well-being and improving biodiversity in towns and cities.<\/p>\n<p>In the sponge city, the blue\/green infrastructure can help to collect, store, and reuse urban rainwater sustainably. Due to various sponge city elements, much of the water can slowly evaporate through natural processes and therefore counteract the rising heat in built-on areas. Unsealed and greened areas with a high level of evapotranspiration are ideal in this respect.<\/p>\n<p>Green roofs, trees, rainwater harvesting cisterns and the inclusion of permeable road surfaces are the most important and well-known urban blue\/green solutions in terms of sustainable rainwater management. Above all, it\u2019s retention roofs that help to store water and reduce the impact of stormwater runoff locally.<\/p>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-b557eac elementor-widget elementor-widget-image\" data-id=\"b557eac\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<img decoding=\"async\" width=\"800\" height=\"534\" src=\"https:\/\/climagruen.com\/wp-content\/uploads\/2022\/11\/Retention-Daecher-Stadt-1024x683.jpg\" class=\"attachment-large size-large wp-image-9314\" alt=\"\" srcset=\"https:\/\/climagruen.com\/wp-content\/uploads\/2022\/11\/Retention-Daecher-Stadt-1024x683.jpg 1024w, https:\/\/climagruen.com\/wp-content\/uploads\/2022\/11\/Retention-Daecher-Stadt-300x200.jpg 300w, https:\/\/climagruen.com\/wp-content\/uploads\/2022\/11\/Retention-Daecher-Stadt-768x512.jpg 768w, https:\/\/climagruen.com\/wp-content\/uploads\/2022\/11\/Retention-Daecher-Stadt-1536x1024.jpg 1536w, https:\/\/climagruen.com\/wp-content\/uploads\/2022\/11\/Retention-Daecher-Stadt-2048x1366.jpg 2048w\" sizes=\"(max-width: 800px) 100vw, 800px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-c0a97cd elementor-widget elementor-widget-menu-anchor\" data-id=\"c0a97cd\" data-element_type=\"widget\" data-widget_type=\"menu-anchor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"elementor-menu-anchor\" id=\"retentionsdach\"><\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-c41e744 elementor-widget elementor-widget-spacer\" data-id=\"c41e744\" data-element_type=\"widget\" data-widget_type=\"spacer.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"elementor-spacer\">\n\t\t\t<div class=\"elementor-spacer-inner\"><\/div>\n\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-a6f9c6c elementor-widget elementor-widget-heading\" data-id=\"a6f9c6c\" data-element_type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">The retention roof \u2013 the heart of the sponge city<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-47a2387 elementor-widget elementor-widget-text-editor\" data-id=\"47a2387\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p>Green roofs have been used to control rainwater for decades because they retain rainwater and delay peak flows, which cuts the risk of flooding. An even greater contribution is made in this case by retention roofs, which are designed to delay runoff considerably and have exceptional water storage capacity.<\/p>\n<p>Retention roofs cut peak flows because they retain and store rainwater and increase the evaporation performance of roofs. Consequently, the risk of city-centre flooding decreases and the urban water supply is more like a natural one.<\/p>\n<p>Shetty et al. (2022) investigated the impact of green roofs on urban rainwater runoff. Their findings showed that the retention rate of a standard green roof is already just under 100% at low precipitation. During heavy rainfall, a normal green roof can retain approx. 65.2 % of the water. This percentage rises to 75.6 % if the rainwater is stored too.<\/p>\n<p>In addition to providing flood protection, retention roofs also offer other benefits. For instance, they improve the urban microclimate, biodiversity, rainwater management and people\u2019s well-being. Another huge advantage is that it can be used as a planning tool for existing infrastructure.<\/p>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-bb362c2 elementor-widget elementor-widget-image\" data-id=\"bb362c2\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"800\" height=\"666\" src=\"https:\/\/climagruen.com\/wp-content\/uploads\/2022\/11\/Wasserkreislauf-Retentionsdach-1024x852.jpg\" class=\"attachment-large size-large wp-image-8229\" alt=\"\" srcset=\"https:\/\/climagruen.com\/wp-content\/uploads\/2022\/11\/Wasserkreislauf-Retentionsdach-1024x852.jpg 1024w, https:\/\/climagruen.com\/wp-content\/uploads\/2022\/11\/Wasserkreislauf-Retentionsdach-300x250.jpg 300w, https:\/\/climagruen.com\/wp-content\/uploads\/2022\/11\/Wasserkreislauf-Retentionsdach-768x639.jpg 768w, https:\/\/climagruen.com\/wp-content\/uploads\/2022\/11\/Wasserkreislauf-Retentionsdach-1536x1278.jpg 1536w, https:\/\/climagruen.com\/wp-content\/uploads\/2022\/11\/Wasserkreislauf-Retentionsdach.jpg 1654w\" sizes=\"(max-width: 800px) 100vw, 800px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-fe77e37 elementor-widget elementor-widget-text-editor\" data-id=\"fe77e37\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p>Fig. 1: Retention roof water cycle; our own graphic 2022<\/p>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-7301ae3 elementor-widget elementor-widget-spacer\" data-id=\"7301ae3\" data-element_type=\"widget\" data-widget_type=\"spacer.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"elementor-spacer\">\n\t\t\t<div class=\"elementor-spacer-inner\"><\/div>\n\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-d77ce68 elementor-widget elementor-widget-text-editor\" data-id=\"d77ce68\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><strong>Bibliography<\/strong><br \/>\nShetty, Nandan; Wang, Mark; Elliott, Robert; Culligan, Patricia (2022): Examining How a Smart Rainwater Harvesting System Connected to a Green Roof Can Improve Urban Stormwater Management. In: Water 14 (14), p. 2216. Retrieved here: <a href=\"https:\/\/www.mdpi.com\/2073-4441\/14\/14\/2216\" rel=\"noopener\">Link<\/a><\/p>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t<\/div>\n\t\t","protected":false},"excerpt":{"rendered":"<p>In view of rapid urbanisation and climate change, towns and cities worldwide need to manage water-related risks and make changes in the interests of sustainability and resilience. In this case, urban resilience means, in particular, adapting to the climate. In terms of extreme weather events, it will be vital to modify the infrastructure to solve [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":11628,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[10],"tags":[253,255,252,251],"class_list":["post-15646","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-posts","tag-cities","tag-retention-en","tag-sponge-city","tag-water-management"],"acf":[],"_links":{"self":[{"href":"https:\/\/climagruen.com\/en\/wp-json\/wp\/v2\/posts\/15646","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/climagruen.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/climagruen.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/climagruen.com\/en\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/climagruen.com\/en\/wp-json\/wp\/v2\/comments?post=15646"}],"version-history":[{"count":0,"href":"https:\/\/climagruen.com\/en\/wp-json\/wp\/v2\/posts\/15646\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/climagruen.com\/en\/wp-json\/wp\/v2\/media\/11628"}],"wp:attachment":[{"href":"https:\/\/climagruen.com\/en\/wp-json\/wp\/v2\/media?parent=15646"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/climagruen.com\/en\/wp-json\/wp\/v2\/categories?post=15646"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/climagruen.com\/en\/wp-json\/wp\/v2\/tags?post=15646"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}