Data used in this analysis:

The primary data used in this analysis was provided by Watershed Watch Salmon Society (2018). It consisted of some shapefiles and excel tables with information about over 155 sites of flood infrastructure located in tributaries from the Fraser River.

All of the sites had data provided for location, type of infrastructure, length of the upstream potential salmon-bearing habitat, and whether they were already Fish-Friendly or not.

They also provided data about water quality (dissolved oxygen and temperature) of some of the upstream waterways, but not all of them. Dissolved oxygen (DO) of less than 5mg/L and temperatures above 18C were noted to be extremely unsuitable for salmon, as per the Department of Fisheries and Oceans (source).

Base data was sourced from DataBC, (Government of British Columbia, 2018) including the base map, administrative boundaries, and waterway locations.

Error:

The water quality data was collected by Watershed Watch staff, summer students, and contracted professionals. In sorting through this data, it became clear that it had a great deal of potential for error. Often only one reading was taken for DO or temperature, and recorded by non-professionals. For more accurate water quality data, multiple samples should be taken over the course of several days, within the same season, and by those who are adequately trained to use the equipment.

Limitations and future research:

The water quality data was not available for all the infrastructure sites, and thus it is recommended that Watershed Watch continues to collect this information.

Data for the other possible criteria should also be collected for the infrastructure and waterways, such as information on riparian shading, if the current floodgate / pump station is due for upgrades or is clearly outdated, if local communities or First Nations groups are interested in the waterways, what type of land use the waterways run through and the impact this has on salmon habitat, if the sites are located near gravel bars or other significantly suitable salmon habitat, and much more.

The “fish-friendly” sites should also be analyzed, to determine if they are truly open long enough to create suitable fish habitat.