Proceedings - Teaching and Learning Centre - Simon Fraser ...

Fraser River Action Plan 3rd Research Workshop
Transportation, Industry and Dangerous Goods
Consequences for Stream Ecosystem Health
P. Zandbergen 1 , K. Hall 2
1 Resource Management and Environmental Studies
University of British Columbia
2 Westwater Research Centre
University of British Columbia
Many diffuse sources contribute to the total discharge of pollutants into the Brunette River watershed. In
addition to general transport, these include industrial and commercial sites, residential areas, spills, leaks, dumps
and accidents. These discharges are measured in an integrated way by determining stormwater loadings; spatial
analysis with land use intensity can reveal some of the contributing sources. However, source identification can
be difficult and sporadic events can be missed. A closer examination of some of the sources is, therefore,
considered useful.
Accidents with the transportation of dangerous goods have been a public health and emergency concern.
Accident records have revealed approximately 50 incidents in the watershed over the period 1990-1994, but very
few resulted in an actual spill. Reported spills to watercourses from other sources have been much more
frequent; approximately 100 spills were reported for 1990-1994, with petroleum products accounting for the
majority of identified substances. Preliminary comparisons with stormwater loadings indicated that while spills
may in the short-term and locally have very significant impacts, in the long-term, other contributions are likely to
be more damaging to overall stream ecosystem health.
In order to asses the ecological consequences of urbanization in the watershed, we have to interpret what the
contaminant levels mean to living organisms. A variety of methods exist to relate exposure levels to stream
ecosystem health. These include comparing water and sediment quality to agency criteria, measuring
accumulation of contaminants in organisms, performing laboratory bioassays and determining changes in the
population and community structure of aquatic organisms.
Water quality in streams in the Brunette River watershed frequently exceeds established criteria for the
protection of aquatic life during periods of stormwater runoff, especially for trace metals such as copper and
zinc. A very large percentage of the surface sediments in the watershed contain trace metal levels that fall
between the TEL (Threshold Effect Level) and PEL (Probable Effect Level) criteria recently established by
Environment Canada. Sediment bioassays with chironomids have demonstrated lower survival and poorer
growth of these benthic invertebrates when compared to reference stations.
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