Do you know where you really are in the shifting paradigms of stormwater management?

Article by Andy Reese examines how our ideas about stormwater have changed over time

Andy Reese, in the July/August 2001 issue of Stormwater Magazine, took an irreverent look at how our ideas about stormwater have changed since the 1800s. In his article titled “Stormwater Paradigms”, Andy Reese insightfully looks back at why we pursued stormwater management in ways which unknowingly – at the time – foreclosed opportunities for more sustainable, livable communities. Reese describes a paradigm shift as follows:

It’s what we think is true and right about a certain subject. It’s the grid through which we put all information and input about a subject. In fact, it’s everything we think is true about something …..Whether our paradigm is, in fact,  true and effective is not the point. We believe it is. And we only reluctantly change our ways and agree with someone else’s paradigm. Stormwater management is full of cantankerous people with strongly-held opinions.”

These paradigms comprise a continuum. People and communities progress at different rates along the continuum – nearby communities in the same region may even be guided by different paradigms. It is much easier to know what the next paradigm is than to move into the next paradigm. The nine paradigms as defined by Reese are listed below.

Nine Paradigms Explained

Paradigm 3 generally reigned from after World War I until the 1970s or so. The modern urban stormwater infrastructure was born, consisting of an efficient drainage system with catch basins and pipes leading to the nearest stream. From a British Commonwealth perspective, Paradigm 3 can be described as an enlightened Edwardian view.

Some time after World War II it became apparent to engineers throughout North America that the fruit of an efficient stormwater system is downstream flooding and channel erosion. This resulted in a new idea to solve flooding forever: on-site detention (Paradigm 4).

The Modern Era

In the 1970s, the literature began to reflect a new concept: stormwater master planning. The idea was that we could construct a hydrology model (how much water, how often?) and a hydraulic model (how fast and high does the water from the hydrology model go?) of a watershed and then do “what if” analyses until we found the perfect solution to flooding problems – current problems and those only imagined.

In the late 1980s, a new breed of paradigms emerged. Each solved the immediate problem of the past paradigm and created a more insidious problem of its own. Knowledge and technology created a real or perceived need for higher, more demanding levels of stormwater management – and regulation.

It’s not that these past paradigms have disappeared. They are alive and well in various parts of the North American continent.

Being aware of the new paradigms makes it increasingly less acceptable to do business as usual. The challenge ahead is to define and then actually demonstrate that a healthy watershed approach produces the full range of effective results efficiently.


Before STORMWATER, The Journal for Surface Water Quality Professionals, there was no single publication written specifically for  the professional involved with surface water quality issues, protection, projects, and programs.

To Learn More:

To read the complete Andy Reese article, click on this link to download a copy of  Stormwater Paradigms.

Build a Vision, Create a Legacy

In 2002, the US-based Andy Reese collaborated with three British Columbians – Kim Stephens, Erik Karlsen and Robert Hicks – to co-author an article that was published in FreshOutook Magazine. Titled Stomwater Management: Build a Vision, Create a Legacy, this article provided the opportunity to introduce the Tenth Paradigm: Build a Vision, Create a Legacy.

In June 2008, at the first in  the Vancouver Island Learning Lunch Seminar Series, a pilot program for local government continuing education in British Columbia, Kim Stephens told the story behind the ‘Tenth Paradigm’ this way:

“After his article was published, I said to Andy, an obvious question is …so, what is the tenth paradigm? …. because people are used to lists of ten. You have only nine. From a British Columbia perspective, it actually was fortuitous that Andy limited himself to nine paradigms. Kim stephens (120p)At the time, we were in the final stages of writing Stormwater Planning: A Guidebook for British Columbia. Long story short, Andy provided us with timely inspiration to brand the Guidebook approach as representing the Tenth Paradigm. In retrospect, it was serendipity the way things came together, in particular because we were breaking new ground with the water balance methodology and all that it entailed.”

In their FreshOutlook article, the authors state that the ‘Tenth Paradigm’ reaches beyond rainwater/stormwater and associated professionals to engage broader society.   They explain that it involves a wholesale transformation of society’s relationships with water (like anti-smoking or anti-litter), so that the very fabric of society changes over a generation to appreciate and learn to live with urban nature in all its dimensions.

Move from Planning to Action

According to Stephens et al, we can begin to think about the Tenth Paradigm as one involving making decisions aimed at achieving healthier urban watersheds over time. They emphasize that a shared long-term vision is needed to focus the effort that will create a legacy.

The shared vision provides a context for all planning, data collection, sensitivity analyses, capital expenditures, and regulatory changes.  The authors explain that prioritizing goals and actions (ideally through consensus) provides a road map for moving towards a target condition by identifying:

  • The interconnected nature of goals, values and expectations.
  • The risks and the opportunities.
  • What needs to be done to manage the risks and achieve the opportunities.
  • Who should be responsible.
  • A general timeline for implementation.

This ‘road map’ approach addresses the goal of identifying options to change the way that land is developed and redeveloped, so that people, property and natural systems can be better protected; and over time, infrastructure can be managed more efficiently and watersheds can become healthier.

ToLearn More:

To read the FreshOutlook article in its entirety, click on Rainwater/Stormwater Management: Build a Vision, Create a Legacy is the “Tenth Paradigm”. The article provides a philosophical backdrop for Stormwater Planning: A Guidebook for British Columbia, published in 2002.