Coalbed Methane and Salmon: Assessing the Risks
GW Solutions Inc. (GW Solutions) was commissioned by the Pembina Institute to prepare a preliminary assessment of potential impacts on salmon and salmon habitat of coalbed methane (CBM) development. The focus was specifically on a tenure held by Shell Canada Limited (Shell) in the Klappan region of northwest British Columbia (the Shell Tenure).
The Shell Tenure covers an area about one-eighth the size of Vancouver Island and includes the upper headwaters of three major salmon-bearing rivers — the Stikine, Skeena and Nass — as well as some of their tributaries.
Currently, there is no commercial production of CBM anywhere in British Columbia. In North America, the majority of existing CBM operations are found in areas with hydrological, geological, topographical and ecological conditions that are very different from those in the northwest part of the province.
Specifically, throughout the rest of the continent there are no known commercial CBM operations in remote, alpine and subalpine regions or in salmon-bearing watersheds. As a result, relevant empirical information about the relationships between CBM production and salmon health does not exist.
The present analysis was designed as a first effort to identify whether there may be issues of concern. The study delivers four unique findings:
First, field research confirms that salmon spawning areas exist in the upper Skeena and various tributaries within the Shell Tenure. Coho, sockeye and chinook salmon are present, as are steelhead.
Second, existing scientific knowledge combined with basic modelling suggests that there are several pathways by which CBM production could have impacts on salmon and salmon habitat in the Shell Tenure. These include
- reductions in water quality and damage to stream beds due to erosion and soil mobilization, triggered by cumulative development of surface infrastructure (such as roads, pipelines and compressor and well pads)
- changes in the wetted area, flow and temperature of streams due to complex changes in the interaction between groundwater and surface water, triggered by groundwater removal during CBM extraction.
Third, the types of information needed to describe with greater certainty likely impacts of CBM on salmon and salmon habitat, as well to quantify key indicators, are almost universally missing. These include information about the hydrology, hydrogeology, biology and ecology of the Shell Tenure, as well as detailed build-out plans for Shell’s CBM development proposal.
Fourth, in addition to uncertainties caused by data gaps, there are a series of uncertainties beyond the current mitigation requirements of proponents or regulators of the Klappan CBM project. These include potential environmental stresses resulting from climate change, and cumulative impacts resulting from multiple resource developments in any of the affected watersheds. Current provincial regulations do not systematically address the cumulative impacts of multiple CBM wells in a single tenure, let alone the impacts of multiple, adjacent energy developments in a watershed.
This report concludes that further, detailed investigations are essential to determine whether mitigation of impacts will be required and, if so, feasible to implement. Given the sensitivity of salmon to disturbance in their critical habitats, it is fully possible that impacts cannot be mitigated within acceptable limits. This can only be confirmed with additional research.