Changes

This article is about definitions. The regional context for LID is presented in [[Urbanization]] and [[Climate change]].  

This article is about definitions. The regional context for LID is presented in [[Urbanization]] and [[Climate change]].  

This guide has been developed as a tool to help developers, consultants, municipalities and landowners understand and implement more sustainable stormwater management planning and design practices in their watersheds. Many jurisdictions have defined the term low impact development. For this document, the following definition, adapted from the [https://www.epa.gov/nps/urban-runoff-low-impact-development United States Environmental Protection Agency] will be used:

This guide has been developed as a tool to help developers, consultants, municipalities and landowners understand and implement more sustainable stormwater management planning and design practices in their watersheds. Many jurisdictions have defined the term low impact development. The Sustainable Technologies Evaluation Program uses the following definition:  

 

systems and practices that use or mimic natural processes that result in the [[infiltration]], [[evapotranspiration]] or [[Rainwater harvesting|reuse]] of stormwater in order to protect water quality and associated aquatic habitat.}}

:::Low impact development (LID) is a stormwater management strategy that seeks to mitigate the impacts of increased runoff and stormwater pollution by managing runoff as close to its  source as possible. To accomplish this, it uses practices that help to preserve or to restore predevelopment hydrological and ecological functions. For preservation, it uses site design strategies to minimize runoff and to protect natural drainage patterns. For restoration, it uses distributed structural practices that filter, detain, infiltrate, evapotranspire and harvest stormwater. LID practices can effectively remove sediment, nutrients, pathogens and metals from runoff, and they reduce the volume and intensity of stormwater flows.

The field of stormwater management has undergone considerable evolution in the last 40 - 50 years, from underground drainage systems for rapid water disposal, to stormwater management ponds, to today’s myriad of near-to-nature practices and technologies<ref name ="Fletcher" />. This paradigm shift could be explained by a change of perception about water from a waste to a resource. With this evolution comes the evolution of terminology to describe the latest visions, practices and technologies.

The field of stormwater management has undergone considerable evolution in the last 40 - 50 years, from underground drainage systems for rapid water disposal, to stormwater management ponds, to today’s myriad of near-to-nature practices and technologies<ref name ="Fletcher" />. This paradigm shift could be explained by a change of perception about water from a waste to a resource. With this evolution comes the evolution of terminology to describe the latest visions, practices and technologies.

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==Green infrastructure==

==LID and Green infrastructure==

In many cases, the terms LID and GI are used interchangeably to describe an alternate management approach from the conventional ‘grey’ infrastructure approach. The inconsistent use of these two terms by different agencies and scholars across North America and other parts of the world contributes to the confusion already associated with these relatively new approaches to stormwater management.

In many cases, the terms LID and GI are used interchangeably to describe an alternate management approach from the conventional ‘grey’ infrastructure approach. The inconsistent use of these two terms by different agencies and scholars across North America and other parts of the world contributes to the confusion already associated with these relatively new approaches to stormwater management.

In this guide we make a distinction between LID and GI on the grounds of geographic and structural (engineered) scales of classification and implementation.  

In this guide we make a distinction between LID and GI on the grounds of geographic and structural (engineered) scales of classification and implementation.  

Traditionally, the term infrastructure connotes a requirement that is necessary to keep an urban center functional, while green space connotes a want, putting it at the bottom of priority lists.  

Traditionally, the term "infrastructure" connotes a requirement that is necessary to keep an urban center functional, while green space connotes a want, putting it at the bottom of priority lists.  

The term GI emerged to put more emphasis on green space as a need rather than a want and elevate it within budget priority lists. As such, in addition to traditional water-related infrastructure, GI encompasses non-traditional infrastructure, such as:

The term GI emerged to put more emphasis on green space as a need rather than a want and elevate it within budget priority lists. As such, in addition to traditional water-related infrastructure, GI encompasses non-traditional infrastructure, such as:

*heritage features,

*heritage features,