Bulkley Valley Research Centre - Science in the Public Interest

Cumulative effects assessment for the Morice Watershed

February 19, 2014

Dave Daust, Consultant

Cumulative effects assessments (CEA) are used to estimate the impacts of development. Historically, they have been tied to specific major projects such as mines or pipelines. Over the last three years, I have been part of a team developing and testing bioregional CEA methodology. Our approach is broader and lighter than traditional CEAs: it does not focus on a specific project, but rather examines the impacts of alternative development pathways (e.g., no development, just forestry, forestry and pipelines) in the context of climate change and natural variability. As a case study, we examined impacts to selected values—salmon, grizzly bears, moose and biodiversity—in the Morice Watershed.

Our methodological goals were to be explicit, accessible and easily updated. We summarized publically-defined management objectives for each value and defined risk to be directly relevant to these objectives. We used spatio-temporal simulation, to calculate indicators of risk. The approach used meta-modelling to link together pre-existing models, many of which have been well tested and/or published. Models include road development, logging, natural disturbance, water balance, water flow and landslide run-out. Risk and uncertainty are explicitly linked to indicators via “risk curves” and then risk is estimated.

Preliminary results suggest the obvious: salmon, grizzly bears and biodiversity face increasing risk, under all scenarios. Moose may benefit. Results are hot off the press…I expect to have more detail by the time of the talk.

Nanika Falls