Low-Impact Development technology is a rapidly rising method to address stormwater management and flooding, especially in highly urbanized areas. LID is billed as a promising and sustainable solution to adapt and mitigate the consequences of climate change.
What is Low-Impact Development (LID)?
LID is an approach to land development or re-development proposed in 1998 to manage stormwater as close to its source as possible. It mimics the site’s pre-development hydrology or its original landscape (Clar, 2015).
LID is can also be used to reduce water and pollutant runoffs managing to where its closest to the source. LID can be integrated into the overall site design for a new development area, or it could be an individual small-scale stormwater management application like the use of a rain harvester to collect and filter stormwater (Clar, 2015).
LID Vs Green Infrastructure
LID is sometimes used interchangeably with green infrastructure. However, green infrastructure (GI) is a much broader concept, and its application is beyond that of stormwater management. GI refers to natural infrastructures such as the use of ecosystems, forests, and vegetation to reduce pollution, combat the urban heat island (UHI) effect, capture carbon, improving aesthetics in the urban or city area and preserving the natural environment (Terminology of Low Impact, 2012).
Green infrastructures refer to projects like green roofs, porous pavement, bioswales and berms, rain gardens, urban tree canopy, that uses soil and vegetation for their natural purposes (Terminology of Low Impact, 2012).
Benefits of LID and Green Infrastructures
As the name suggests, low impact development technology does not employ hard engineering solutions that use conventional construction materials like cement and steel to build stormwater infrastructure.
It is a sustainable solution because it meets the criteria of sustainability in 3 areas: environmental, social, and economical. Low impact development reduces energy usage, improves water quality, and promotes natural habitats which benefit the environment. Socially, it increases recreational activities and improves health through cleaner surroundings. Its economic benefits include lesser future costs of stormwater management, and increased property values and local tourism (Green Infrastructure, 2014).
A study that applied LID in a developed area in a new district in Korea shows positive results in reducing stormwater runoffs for both historical and future runoffs from extreme conditions (Lee, Hyun, & Choi, 2013).
The study finds that LID can reduce peak runoffs by up to 66% and runoff volume by up to 121% for historical or past run-offs from storms. For future extreme storms with return periods of up to 80 or 100 years, it can reduce peak runoff by up to 16% and 37% in runoff volume (Lee, Hyun, & Choi, 2013).
The study concludes that LID can be a promising solution to adapt to future flooding and can be integrated into future urban development and stormwater management planning as well.
A video below also demonstrates the benefits of integrating LID and green infrastructure to US urban development.
LID and green infrastructures are not new concepts, but with climate change, nature-based and sustainable solutions are gaining attention for sustainable climate adaptation and mitigation strategies.
To read the study on the integration of LID to a developed area in Korea, click on the link below: