Category Archives: green building

Low Impact Development in the City of Los Angeles

Kudos to the city, which recently passed an ordinance supporting the use of Low Impact Development in the City of Los Angeles. Low Impact Development, or LID “calls for development and redevelopment projects to mitigate runoff in a manner that captures rainwater at its source, while utilizing natural resources including rain barrels, permeable pavement, rainwater storage tanks, infiltration swales or curb bumpouts to contain water. Reports have shown that LID is the most effective and cost-efficient means of managing stormwater and abating water pollution. LID practices are designed to address runoff and pollution at the source. Other low impact development benefits include water conservation, groundwater recharge and greening communities.”

Although mainly known for reducing runoff and pollution, LID is also likely to reduce the need for landscape irrigation, thereby reducing pressure on potable water supplies. It also has the potential to recharge groundwater basins, which are over-drafted in many of California’s urban areas.

LID is just one part of an integrated approach to water management, which looks at ALL available sources of water and matches them to the needs of any given project, seeking an appropriate match between water quantity and quality needed and what is available sustainably. Green building and development should incorporate LID concepts at the earliest stages of site analysis and design, when it is most cost-effective to apply this idea.


The Pyramid of New Water Sources

Here’s an interesting new tool to use when it comes to thinking about or teaching about water supply and conservation.  It’s called The Pyramid of New Water Sources and comes from  Jerry Yudelson , a noted green building authority and author.  I just found this in a blog post from World Water Day at Jetson Green.

A tool for prioritizing water supply sources by cost & complexity.

The Pyramid of New Water Sources

The Pyramid shows a progression of “new water” sources, ranging from the simple and free/cheap alternatives at the bottom to more complex and expensive at the top (with desalination and new water sources at the top).  Everything below the top level is about efficiency and reuse.  It’s a great reminder that when it comes to finding new supplies of water, using what we’ve already got more efficiently is almost always the most practical and cost-effective approach.