What urban stormwater management techniques were used during the early 20th century?5 answersDuring the early 20th century, urban stormwater management techniques primarily involved the rapid transfer of water to sewage systems or ditches, leading to the transportation of pollutants and large volumes of water to rivers and streams. Stormwater management paradigms at that time focused on abating downstream flooding and were mainly engineered solutions. However, as urban stormwater management evolved over the decades, new approaches emerged to address issues like floods and water pollution in urban areas. These new techniques included the use of storm sewers, detention basins, canals, and decentralized retention and infiltration systems, which aimed to control peak flows, improve water quality, and reduce runoff volume through distributed management practices.
Which kinds of urban water management are there?4 answersVarious kinds of urban water management approaches exist to address the challenges posed by factors like climate change, population growth, and water scarcity. These include Integrated Urban Water Management (IUWM), which integrates non-conventional water sources like stormwater and recycled wastewater to enhance water security and sustainability. Additionally, frameworks such as sustainable development, ecological modernization, socio-technical framings, urban political ecology, and radical ecology offer diverse perspectives on urban water sustainability, focusing on aspects like meeting the needs of the urban poor, technological innovation, power dynamics in water management, and fundamental societal reorganization to address ecological crises. Urban water governance has also evolved from centralized statutory agencies to more fragmented systems involving public and private entities, reflecting changes in water law and governance structures to adapt to global challenges like climate change and urbanization.
How does urban sprawl affect stormwater runoff?4 answersUrban sprawl, characterized by the expansion of urban areas and the conversion of natural land resources into impervious surfaces, has a significant impact on stormwater runoff. The increase in impervious surfaces such as roads, buildings, and parking lots reduces the ability of the land to absorb and drain stormwater during rainfall events. As a result, urbanization leads to higher volumes and peak flow rates of stormwater runoff, as well as a degradation in runoff quality due to increased concentrations of pollutants. The rapid pace of urbanization has also overwhelmed existing underground drainage systems, which are unable to handle the current flow conditions. This has resulted in destructive stormwater impacts in urban areas, including economic losses, fatalities, and damaged properties. To mitigate these effects, various runoff reduction methods have been implemented, with average runoff reduction percentages ranging from 43% to 61% under different rain events. Incorporating sustainable stormwater management practices, such as promoting infiltration and storage of runoff, can help reduce the vulnerability to urban floods.
What are the sustainable urban stormwater drainage practices?5 answersSustainable urban stormwater drainage practices include Sustainable Urban Drainage Systems (SUDS), Low Impact Development (LID), Best Management Practices (BMP), Water Sensitive Urban Design (WSUD), and the Sponge City Programme (SCP). These practices aim to manage stormwater more efficiently in urban areas by mitigating flood risk, reducing pollution of water bodies, and restoring the natural water balance. SUDS focus on distributed stormwater management and control, promoting infiltration, evapotranspiration, rainwater harvesting, and reuse. LID is a green infrastructure approach that eases surface runoff through practices such as bioretention cells, bioswales, and permeable pavement. WSUD and SCP also emphasize sustainable stormwater management through integrated approaches considering climate change, land use patterns, reuse, treatment, ecology, and societal aspects. These practices can help minimize flooding, enhance groundwater recharge, and reduce the impact of urbanization on hydrologic systems.
What are the benefits of controlled flooding in urban areas?5 answersControlled flooding in urban areas has several benefits. Firstly, it helps in reducing the impact of excess runoff during short-duration rainfall events, thereby mitigating urban pluvial flooding. Secondly, it can effectively reduce runoff for small rainfalls, which helps in managing urban flooding. Additionally, controlled flooding can help in retaining, detaining, infiltrating, or reusing rainwater on-site, which is important for sustainable water management in cities. Moreover, it can provide a scientific basis and technical support for urban flood control and drainage planning, allowing city management committees to assess the potential risk of waterlogging and plan accordingly. Lastly, controlled flooding can help in preventing surface floodwater and automatically controlling urban floods in real-time, making cities more resilient to flooding.
How can urban rainwater management contribute to sustainable development?5 answersUrban rainwater management can contribute to sustainable development by addressing the challenges of water scarcity, pollution, and climate change in urban areas. Implementing green infrastructures such as bioretention systems with active control technology can enhance the treatment capacity of rainwater, mitigating runoff and capturing pollutants. Rainwater harvesting (RWH) systems can also play a significant role in meeting the growing water demand by reusing and recycling rainwater, thereby conserving water resources. Additionally, integrated storage solutions and the utilization of water wastage through runoff can help enhance groundwater levels and support resilient development in the face of climate change. Sustainable Urban Drainage Systems (SUDS), Low Impact Development (LID), and Water Sensitive Urban Design (WSUD) are important aspects of urban stormwater management that can contribute to sustainable and resilient urban water management. Furthermore, information modeling of buildings and cities can provide a basis for simulations and analyses that aid decision-making and prevent problems in the management of rainwater.