Green Infrastructure & Community Design: “Webinar on Sustainable Rainwater Management”



Note to Reader:

The career focus of Colorado-based civil engineer Paul Crabtree is on the integration of intelligent urban infrastructure with New Urbanism and Smart Growth Planning. Among his many accomplishments, Paul Crabtree is the leader of the Rainwater in Context Initiative in the United States.

In February 2013, Paul Crabtree delivered a live webinar on the practical aspects of implementing “Green Infrastructure & Community Design: Rainwater Management”. He explored how rainwater management based on good urban design principles can help to harmonize urban man and nature.

The webinar was hosted by Forester University. is available for viewing and is eligible for Continuing Education Credits.  Click on the following link for further information on how to access the webinar:


Paul Crabtree on ‘Harmonization of Man and Nature’

“Is your rainwater management design effective?,” asks Paul Crabtree. “Effective rainwater management requires a focus on the harmonization of man and nature AND the skill sets of a spectrum of professionals and citizens. Too often, the reverse is true. The result – ineffective rainwater management plans, increased maintenance costs, and ultimately,redesign.”

“A key goal of the Rainwater-in-Context Initiative is to help get the United States on the correct path for sustainable rainwater management practices. Rainwater-in-Context unites New Urbanism, rainwater and watershed management, Smart Growth, water reuse, low impact, light imprint, and other sustainable practices toward a holistic approach to rainwater. Combining green infrastructure with good urban planning can result in extraordinary solutions,” explains Paul Crabtree.


Seven Key Messages

In the webinar, Paul Crabtree illustrates rainwater management design that is closely connected with and based on good urban design principles, harmonizing man and nature and resulting in an effective and successful long-term rainwater management program. He elaborates on seven key messages to make the case for ‘doing business differently’ in the United States. According to Paul Crabtree:

  1. The existing US regulatory climate favors sprawl.
  2. Rainwater practices need to confront and handle the decades old legacy of pave, pipe and dump development patterns.
  3. The emphasis on the site scale only has obscured the use and implementation of neighborhood, community, regional and watershed scales.
  4. The gradient scale of contexts from natural to urban are often ignored.
  5. Smart Growth development priorities do not receive sufficient emphasis.
  6. The ecological footprint of the human species has not been adequately factored into the solution.
  7. The Best Management Practice (BMP) Manuals need a revamp

Paul Crabtree’s vision is that these seven theme areas will provide communities with an informed frame-of-reference for moving from awareness to action.


Key Message #1 – The existing US regulatory climate favors sprawl:

“The implementation of rainwater controls into the regulatory structure has, in many cases, acted to usurp the local land use codes. At a time when communities are trying to figure out how to favor infill, redevelopment, and compact development, the unintended consequences of the rainwater regulations favor low density sprawl,” states Paul Crabtree.


Key Message #2 – Rainwater practices need to confront and handle the decades old legacy of pave, pipe and dump development patterns:

“America’s pre-occupation with Sprawl has left a landscape of large swaths of developed, often underused or vacant land.  Going forward, water resource protection must shift away from its mindset of how to continuously handle new growth to reckoning with the extensively disturbed, connected, impervious landscape now before us.” 


Key Message #3 – The emphasis on the site scale only has obscured the use and implementation of neighborhood, community, regional and watershed scales:

“The legacy of site-by-site assessment and assignment of BMPs leaves behind a system that favors new low-density development even as abandoned old development spills runoff and pollutants into drainage systems.”

“This situation needs to be considered from all scales. For example, a new rainwater regulation should not be considered complete without having a Regional Watershed Analysis completed and key larger scale leverage points incorporated into the permit.”


Key Message #4 – The gradient scale of contexts from natural to urban are often ignored:

“Different urban contexts require different solutions, just as differing watershed conditions do.  Both should be differentiated in effective watershed management plans.  The Principles of Green Infrastructure elucidate this concept.”

To Learn More: Click on


Key Message #5 – Smart Growth development priorities do not receive sufficient emphasis:

“Smart Growth principles prioritize growth beginning with redevelopment and infill of existing fabric. Sprawl repair has been too often ignored.”


Key Message #6 – The ecological footprint of the human species has not been adequately factored into the solution:

“All rainwater regulations have been based on impacts per acre with no consideration of impacts per capita. An analysis and regulation of rainwater impacts on a per capita basis would favor more compact development, which has well-proven benefits to the watershed as a whole.”

“The ‘water-balance’ diagrams that show worse and worse hydrology as density increases need to be counter-pointed with watershed diagrams depicting the benefits of compact development patterns.”

“Density is bad at the site-only scale” – Paul Crabtree


“Density is good at the watershed scale” – Paul Crabtree


Key Message #7 – The Best Management Practice (BMP) Manuals need a revamp:

“Current BMP Manuals are riddled with diagrams that depict Low Impact Development (LID) applied to sprawl, as if those are exemplars.  The manuals need to help educate and provide examples of good, compact development patterns in walkable neighborhoods, and show practices at scales other than the site only.” 

“BMP Manuals need to be completely revamped to vet the sprawl ‘exemplars’, provide some basics of good urban design, show how to retrofit sprawl, and how to address the neighborhood, the corridor, the community, the watershed; and the varying contexts within them,” concludes Paul Crabtree. 


Exemplars of sprawl development like these need to be removed from BMP Manuals” – Paul Crabtree


More from Paul Crabtree

Click on the links below to read articles posted previously on the website and featuring Paul Crabtree.

Cross-Border Alignment: Connecting the Dots Between Land Use Planning, Development, Watershed Health AND Infrastructure Management — “We are working to better match rainwater and stormwater management to the development context through the integration of rainwater into all planning scales, from the region to the building,” stated Paul Crabtree.

REPORT FROM STORMCON 2011: “Changing the Rules: How Will New Stormwater Regulations Affect Municipal Programs in the United States” — “If you make it too hard to make it through the approvals then the person that may be willing to do the right project – that is. a redevelopment site will never make it to implement the right project,” stated Paul Crabtree.


The View from British Columbia

“Paul Crabtree and other American thought leaders, such as writer and speaker Andy Reese, strive to improve our development and engineering practice by providing thought provoking articles and insight into common practice. Both suggest the need to examine hydrology (and hence rainwater management) from a watershed view and to seek more accurate answers than those often derived by using standard approaches that provide consistent answers to regulatory questions,” observes Jim Dumont, Engineering Applications Authority for the Water Balance Model Partnership, and a Canadian member of the Rainwater-in-Context Initiative

“In British Columbia we are taking the watershed approach to address the concerns surrounding the need to protect our small headwater streams from urban impacts. We are going forward in our endeavors to provide the answers to how the streams might be impacted and then to describe how we can avoid those impacts. Only be examining the stream can we provide the necessary direction to the planners and designers of our urban environment.”


Sprawl Repair Has Been Too Often Ignored

In commenting on the range of scenarios introduced with Paul Crabtree’s Key Message #5, Jim Dumont states that “the thought that someone has a vision that would protect 87.5% (8,750 acres out of 10,000 acres) of a watershed while providing housing for a population of 10,000 people is wonderful.”

“This may be possible if or when there is a single land owner and a single development within that watershed. The situation we have experienced in British Columbia, especially in a 10,000 acre watershed, is one that encompasses 2,000 different property owners – each with a desire to maximize the development potential and cash flow from the sale of their property. This places municipalities in a very difficult position when attempting to preserve the environmental integrity of the watershed.”


Creation of a Consensus-Based ‘Watershed Vision’

“In such a situation where there are many different land owners, each vying for the biggest payback, the good news is that we are now seeing examples of communities moving towards creation of a consensus-based vision of the watershed and a desired future condition for restoration of watershed function – with a time scale for implementation of 50 or 100 years. The importance of a long-range view is that it will allow for modification of the ‘Watershed Vision’ as time passes, with a sound start for an exciting future.”

“Creating the Watershed Vision begins with documenting the critical, special, and unique areas that should be protected from change or should be enhanced to increase the environmental value and integrity of those protected parts of the watershed. The next step involves deciding what form and function should be allowed in the land use planning; from residential through institutional to commercial and industrial,” concludes Jim Dumont.


To Learn More:

In its November-December 2010 issue, Stormwater magazine launched the Green Infrastructure & Community Design Series. Articles in the series have been contributed by members of the Rainwater-in-Context Initiative. The series was initiated in large part by the efforts of Paul Crabtree.

The most recent article in the series was co-authored by Jim Dumont and Kim Stephens,  Canadian contributors to the Rainwater-in-Context Initiative. Published in November 2011, the article elaborates on how science-based understanding has informed the process for moving from awareness to action in British Columbia. To download a copy, click on “Rainwater Management in a Watershed Context – What’s the Goal?”.

“This latest article by Kim Stephens and Jim Dumont makes important comparisons between stormwater management in the US and Canada. Although both are moving toward greater use of green infrastructure, the differences in approach are significant. I believe it’s important to consider the context in which decisions about water quality are made, and practitioners in the US can learn a great deal from BC’s approach,” concluded Janice Kasperson, Editor of Stormwater Magazine.