{"id":29073,"date":"2024-04-16T08:47:57","date_gmt":"2024-04-16T07:47:57","guid":{"rendered":"https:\/\/www.vtei.cz\/2024\/04\/zasakovani-vody-pomuze-s-vedrem-suchem-i-povodnemi-2\/"},"modified":"2024-08-19T16:25:18","modified_gmt":"2024-08-19T15:25:18","slug":"water-infiltration-will-help-with-heat-drought-and-floods","status":"publish","type":"post","link":"https:\/\/www.vtei.cz\/en\/2024\/04\/water-infiltration-will-help-with-heat-drought-and-floods\/","title":{"rendered":"Water infiltration will help with heat, drought, and floods"},"content":{"rendered":"

New predictions of\u00a0climate change impacts in\u00a0the Czech Republic show that rainfall will increase slightly in\u00a0the future. However, in\u00a0combination with the expected increase in\u00a0temperature, evaporation will be\u00a0higher, which will lead to\u00a0long-term water shortage. Forecasts also say that rainfall will be\u00a0distributed differently during the year, which in\u00a0practice means that long periods of\u00a0drought will alternate with sudden torrential rainfall. But this is\u00a0nothing new. In\u00a0the Czech Republic today, there is\u00a0already a lack of\u00a0water; it\u00a0lies on\u00a0the main European watershed, and we\u00a0are therefore highly dependent on\u00a0rainwater. In\u00a0the past, unfortunately, we\u00a0have modified cities and the countryside in\u00a0such a way that rainwater was quickly diverted away \u2013 by\u00a0channelling watercourses, by\u00a0farming methods, and by\u00a0creating sewers. Adaptation measures to\u00a0climate change in\u00a0the field of\u00a0water management can significantly increase the sustainability of\u00a0water resources, reduce the risk of\u00a0floods, and ensure water even in\u00a0times of\u00a0drought.<\/span><\/p>\n

Water in\u00a0the city will improve the microclimate<\/h3>\n

Urban dwellers are the most affected by\u00a0weather extremes, such as\u00a0heat waves or\u00a0torrential rainfall causing local floods. The reason is\u00a0the lack of\u00a0greenery and water, the excess of\u00a0paved surfaces, and the rapid runoff of\u00a0water through the sewers, which during torrential rains causes overloading of\u00a0wastewater treatment plants and, hence, water pollution. In\u00a0order to\u00a0limit these phenomena, it\u00a0is\u00a0crucial that the rainwater is\u00a0retained at\u00a0the point of\u00a0impact. Infiltration and water retention measures can prevent sewers from overflowing during torrential rain in\u00a0urban areas, ensure sufficient water for urban greenery, and improve the microclimate.<\/p>\n

There are many ways to\u00a0deal with water retention in\u00a0the urban areas. In\u00a0Roudnice nad Labem (Fig.\u00a01<\/span><\/em>), for example, they have invested in\u00a0the reconstruction of\u00a0streets and not only added more parking spaces, but, thanks to\u00a0the\u00a0design of\u00a0the architectural studio, they also built a system of\u00a0blue-green infrastructure. Local streets are lined with rain gardens. These capture surface water and allow it\u00a0to\u00a0gradually seep into the subsoil. In\u00a0addition, they planted a number of\u00a0trees, which allowed the water to\u00a0soak in, and used permeable material on\u00a0paved areas.<\/p>\n\"\"<\/a>\n

Fig.\u00a01. Rain gardens line the pavements and roads in\u00a0Roudnice nad Labem
\n(Source: Nadace Partnerstv\u00ed \u2013 Adapterra Awards, photo: V. Herout)<\/h6>\n

It\u00a0is\u00a0not always possible to\u00a0hold all the water in\u00a0the ground at\u00a0once, so\u00a0a combination with retention reservoirs is\u00a0suitable. Thanks to\u00a0them, the rainwater runoff will be\u00a0slowed down, both into the sewage system, which will not get overloaded, and into the surrounding greenery. They have been put it\u00a0into practice, for example, in\u00a0the Suomi Hloub\u011bt\u00edn residential district in\u00a0Prague (Fig.\u00a02<\/span>). Retention reservoirs are located under apartment buildings. Surplus water from these cisterns then flows through outdoor distribution systems into the infiltration areas, open shallow ditches with an infiltration function, and only then does the rest of the water travel to the central infiltration pond and from there through the overflow to the newly meandering Rokytka stream.<\/span><\/p>\n\"\"<\/a>\n

Fig.\u00a02. Below Suomi Hloub\u011bt\u00edn, there are infiltration meadows where water from retention reservoirs flows to\u00a0(Source: Nadace Partnerstv\u00ed \u2013 Adapterra Awards, photo: V. Herout)<\/span><\/h6>\n

Semi-natural restoration of\u00a0watercourses and\u00a0anti-flood\u00a0measures<\/h3>\n

Slowing down water runoff is\u00a0a task not only for the urban environment, but also for watercourses and agricultural landscapes. In\u00a0the last century, the regulation of\u00a0watercourses into narrow straight channels was popular, which means that even low intensity rainfall or\u00a0snow melt can cause significant problems in\u00a0the form of\u00a0floods and inundations. Today, the trend is\u00a0exactly the opposite \u2013 to\u00a0restore watercourses in\u00a0a semi-natural way. Natural and semi-natural watercourses slow down the flow of\u00a0water, enabling regulated overflow, and thus reduce the risk of\u00a0floods.<\/p>\n

A number of\u00a0successful watercourse restorations have been carried out by\u00a0Morava River Basin Management; among them is\u00a0the project to\u00a0widen the\u00a0bed of\u00a0the gravelly Be\u010dva river (Fig.\u00a03<\/span>). The main goal of modifying the watercourse was to reduce the deepening of the riverbed, to widen it, to allow water to spill into the floodplain even at lower flows, and to facilitate the conditions for the movement of ice, which accumulated in the riverbed and caused winter floods. Thanks to restoration of part of the river, it was possible to increase the level of flood protection in three adjacent villages \u2013 \u010cernot\u00edn, Skali\u010dky, and \u00dast\u00ed. Simultaneously, the wide and branching nature of the river enables\u00a0the\u00a0transition of\u00a0surface water to\u00a0groundwater. In\u00a0this way, the landscape can store water for the dry season.<\/p>\n

Slowly draining water is\u00a0a sign of\u00a0a healthy landscape. In\u00a0particular, the landscape of\u00a0South Moravia \u2013 but also other areas in\u00a0the Czech Republic \u2013 suffer from drought due to\u00a0large areas of\u00a0intensive agriculture. The arid landscape cannot absorb water in\u00a0the event of\u00a0rainfall. Water runs off the surface, taking the most fertile topsoil with it, resulting in\u00a0less organic matter in\u00a0the soil and less fertile fields. The rapid runoff of\u00a0water over the surface again causes floods. An\u00a0effective solution to\u00a0these problems are semi-natural anti-flood measures.<\/p>\n\"\"<\/a>\n

Fig.\u00a03. Widening of\u00a0the Be\u010dva river allowed the creation of\u00a0gravel bars (Source: Morava River Basin Management)<\/h6>\n
\"\"<\/a><\/h6>\n
Fig.\u00a04. A polder protects N\u011bm\u010dany from floods \u2013 inlet to\u00a0the reservoir in\u00a0the foreground (Source: Nadace Partnerstv\u00ed \u2013 Adapterra Awards, photo: V. Herout)<\/h6>\n

Flood protection has been implemented, for example, in\u00a0N\u011bm\u010dany (Fig.\u00a04<\/span>). Thanks to\u00a0a series of\u00a0eleven consecutive semi-natural measures, the\u00a0village is\u00a0protected from flood, which it\u00a0had had to\u00a0deal with for a long time. On\u00a0the\u00a0slope above N\u011bm\u010dany, water is\u00a0gradually retained by\u00a0biocorridors, anti-erosion barriers, and ditches created along the road and across the opposite slope. The water that is\u00a0not retained flows via a runoff channel into a grassy river bed and further through a dry polder into a reservoir with a constant level. When the water level is\u00a0higher, the water is\u00a0diverted from the polder through a\u00a0side safety overflow and subsequently from the reservoir into the local watercourse, which ensures a regulated and safe water flow in\u00a0the village.<\/p>\n

Additional examples of\u00a0good practice can be\u00a0found in\u00a0the freely accessible database at\u00a0www.adapterraawards.cz.<\/p>\n

Nominations for successful solutions for the sixth year of\u00a0the Adapterra Awards competition are currently underway. You can join too.<\/p>\n

This informative article has not been peer-reviewed.<\/p>\n","protected":false},"excerpt":{"rendered":"

New predictions of climate change impacts in the Czech Republic show that rainfall will increase slightly in the future. However, in combination with the expected increase in temperature, evaporation will be higher, which will lead to long-term water shortage. Forecasts also say that rainfall will be distributed differently during the year, which in practice means that long periods of drought will alternate with sudden torrential rainfall. But this is nothing new. In the Czech Republic today, there is already a lack of water; it lies on the main European watershed, and we are therefore highly dependent on rainwater. In the past, unfortunately, we have modified cities and the countryside in such a way that rainwater was quickly diverted away \u2013 by channelling watercourses, by farming methods, and by creating sewers. Adaptation measures to climate change in the field of water management can significantly increase the sustainability of water resources, reduce the risk of floods, and ensure water even in times of drought.<\/p>\n","protected":false},"author":8,"featured_media":28783,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[86],"tags":[96,528,2463,3468,3470,3471,3469],"coauthors":[3455,3456],"class_list":["post-29073","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-hydraulics-hydrology-and-hydrogeology","tag-climate-change","tag-flood-protection","tag-infiltration","tag-microclimate","tag-polder","tag-revita","tag-water-in-the-city"],"acf":[],"_links":{"self":[{"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/posts\/29073","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/users\/8"}],"replies":[{"embeddable":true,"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/comments?post=29073"}],"version-history":[{"count":2,"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/posts\/29073\/revisions"}],"predecessor-version":[{"id":32008,"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/posts\/29073\/revisions\/32008"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/media\/28783"}],"wp:attachment":[{"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/media?parent=29073"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/categories?post=29073"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/tags?post=29073"},{"taxonomy":"author","embeddable":true,"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/coauthors?post=29073"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}