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The agenda for the half-day forum was structured in four parts. “The forum program was a mix of storytelling, showcasing, sharing and teaching so that we would achieve the learning outcomes,” reports Ted van der Guilik. “Our objective in the first two segments was to engage and energize our audience. For this reason, we conducted them as town-hall sharing in order to prime everyone for the teachable moment in segment #3.”

“We are experiencing wetter, warmer winters and longer, drier summers,” stated Kim Stephens. “BC dodged a bullet during the 2015 drought – that leads us to focus on how the decisions those in local government make on a daily basis impact on the water balance. This perspective frames the bigger picture and sets the stage for drilling down into the details of the Water Balance Methodology.”

The Winston Churchill quote provided a way to change the pace, capture audience attention and set the stage for the balance of the ‘look back to look ahead’ theme that characterized the storytelling in the opening segment of the forum. If there is a living memory of the way things were, then it should be possible to implement standards of practice that would replicate and restore a desired watershed condition.

“Getting to this point has involved the re-thinking of traditional approaches to urban hydrology and computer modelling,” wrote Tom Debo, a former colleague and friend of Ray Linsley. “Drainage engineers have traditionally thought in terms of flow rates, not volumes. In dealing with urban hydrology, we need to focus on how much rainfall volume has fallen, how we are going to capture it, and what we are going to do with it.”

“The Water Balance Methodology is based upon watershed and stream function and operation. Understanding how precipitation makes its way to the stream allow us to assess how a watershed and stream operates and to analytically demonstrate impacts of development and the effectiveness of any mitigation works,” states Jim Dumont.

“Water Balance adaptive action is necessary because we may be crossing an invisible threshold into a different hydro-meteorological regime in Western North America,” stated Kim Stephens. “Annual volumes of water entering and exiting our regions are not necessarily changing; instead, what is changing is how and when water arrives – it is feast AND famine. In other words, the ‘new normal’ in British Columbia is floods and droughts.

“We now realize that our current risk assessments with respect to climate disruption are built on confidence in relative hydrologic stability that no longer exists. This changes everything. We had no idea until recently of how much influence the hydrological cycle has on our day to day lives or on the broader conditions that define the distribution and diversity of life on this planet,” states Bob Sandford.

The methodology is a pragmatic outcome of a ‘design with nature’ guiding philosophy that had its genesis more than two decades ago. “Looking back over the past 20-plus years, if the Stewardship Series was the first wave, the work of UBC’s James Taylor Chair on Sustainable Urban Landscapes was the second, and the Water Balance Approach is the third,” stated Erik Karlsen. “Each of these ‘waves’ was initiated by different ‘groups’, but over time they merged from one to the other.”

The volume-based approach that is being implemented in British Columbia picks up the baton that Dr. Ray Linsley started more than a generation ago. As a professor at Stanford University, Linsley pioneered the development of continuous hydrologic simulation as the foundation for water balance management. He was a true giant of the profession through distinguished teaching, research, professional practice and service to government.

“The litmus test for an acceptable Watershed Target is that the resulting RAINwater management solutions make sense, are affordable and result in net environmental benefits at a watershed scale. For a performance target to be implemented and effective, it must have feedback loops,” states Ted van der Gulik.