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“It helps to look back to understand how we got to here. In 2000, DFO released Urban Stormwater Guidelines and Best Management Practices for Protection of Fish and Fish Habitat. By 2007, however, we had concerns about how the document was being interpreted and applied. ‘Beyond the Guidebook 2007’ represented the initial course correction,” stated Corinio Salomi. The Partnership for Water Sustainability has since released two more in the Beyond the Guidebook Series – in 2010 and 2015.

Rainwater management is at the heart of a contemporary approach to land development in balance with the natural environment. In 2004, Kim Stephens provided this perspective: “BC stormwater criteria and tools are receiving increasing recognition across North America because of their unique emphasis on solving both flooding and environmental problems at the source. This rethinking of traditional approaches to urban hydrology is helping to achieve higher levels of stream protection by integrating land use planning with volume-based strategies.”

A UN report warns extreme weather events that historically happened about once in 100 years could hit coastal cities yearly by 2050. Cities need to prepare now. “This is a wake-up call that we still need to do more to mitigate as much [climate impact] as possible. We’re not going back to normal—whatever normal once was,” stated Mandy Ikert. She says reports like this one are important: They help rally support from larger nations and financial institutions for protecting all cities from the effects of climate change.

How water gets to a stream, and how long it takes, is not well understood among land and drainage practitioners. “A lack of explicit identification and justification of the assumptions and simplifications made in the analysis of stormwater impacts has resulted in stormwater systems that address hypothetical as opposed to actual site characteristics and development impacts,” stated Shelley Ashfield. “Learning from this experience, the Town now requires that assumptions be stated and explained. We are saying WHAT is your assumption, and WHY.”

The industrialization of Vancouver was rapid, and soon the creeks that connected land-to-ocean were buried. “Streams such as Still Creek and others like it were once considered a nuisance, They would often get in the way of road construction or buildings. They were also these dumping grounds for garbage, so there was really this incentive to bury them and that’s kind of just what happened,” stated Uytae Lee. “We’re sort of finally realizing that nature has a lot more value than we often give it credit for.”

“The way we have historically developed and drained land has disconnected hydrology from ecology. The consequences of this disconnect are more erosion and flooding, loss of baseflow and aquatic habitat, and an unfunded infrastructure liability for stream stabilization. Communities have for the most part failed to properly address root causes of ‘changes of hydrology’, as well as subsequent impacts of those changes on natural creekshed function,” states Peter Law.

As problems of flooding and overflow become more common, communities butt up against the reality of having to pay for repairs and improvements. “And so when rainfall changes, and when climate changes, the system doesn’t provide the same level of service that it used to. Where communities used to be able to rely on money coming down, or raining down, from the federal government, now the federal government is there to say, we’ll give you money…but you’re gonna pay us back. Paying more for infrastructure and utilities is the new reality,” Greg Kacvinsky said.

“Innovative strategies understand flood as a natural process to work with, rather than resist. Non-structural, soft and nature-based solutions to flood adaptation are replacing centralised and engineered technologies. These projects use climate change positively to provide multiple added benefits,” wrote Elisa Palazzo. “Looking at how cities are designed and performing in Australia, there is plenty to learn from the international experience. We have a lot to do to adjust this knowledge to the local context.”

“Years ago I was privileged to travel around the US with EPA putting on seminars,” stated Andy Reese in 2011. “Three off-the-cuff words have probably have had the biggest impact in influencing land design of any sort of regulatory program that ever was, and perhaps that ever will be. Those three words were maximum, extent and practicable. Back then, none of those words were capitalized. They were just a made-up term. But MEP is now taking on green infrastructure overtones, sustainability overtones, LID overtones, and on and on.”

Columbia Engineering researchers have demonstrated that stormwater runoff extremes have been dramatically increasing in response to climate change and other anthropogenic changes to the environment. The researchers also found that storm runoff has a stronger response than precipitation to human-induced changes (climate change, land-use land-cover changes, etc). “Our work helps explain the underlying physical mechanisms related to the intensification of precipitation and runoff extremes,” Pierre Gentine said. “