Water Stewardship Information Sources

Citation Triton Environmental Consultants Ltd. 2007. Water Quality Assessment Following an Accidental Release of Sodium Hydroxide: Final Report. Prepated for Canadian National Railway Company.
Organization Cheakamus Ecosystem Restoration Technical Committee
URL http://www.certc.ca/_pdf/WaterQualityReport-FinalReportSept07.pdf
Abstract/Description or Keywords On August 5, 2005, the Cheakamus River was affected by an accidental release of sodium
hydroxide following a train derailment in the Cheakamus canyon approximately 15 km north of
Squamish, British Columbia. The derailment resulted in the release of approximately 45,000
litres of sodium hydroxide into the Cheakamus River.
Three water quality monitoring programs were implemented in order to determine if NaOH had
affected water quality and included: (1)sampling of drinking water in wells within 100 meters of
the river; (2) collection and analyses of water samples from the Cheakamus and Squamish rivers
and the Squamish River Estuary to assess water quality in the context of recreational activities
and protection of freshwater aquatic life; and, (3) surface water sampling during remediation of
the spill site. Results of the emergency sampling program indicated NaOH was carried through
the system but did not persist in the environment. The Cheakamus River was cleared for
recreational purposes within 24 hours and the drinking water closure was lifted within 48 hours
of the spill. Sampling during remediation activities indicated remedial activities did not affect
water quality in the Cheakamus River. Lastly, a longer-term river pH monitoring program
focusing on increased seasonal rainfall was implemented to evaluate if any NaOH residues
remained which might affect pH in the Cheakamus River. Results of the above monitoring
programs showed the effects of the spill were limited to a few hours after the event and that the
hyperalkaline pulse was transient with normal pH conditions returning once the spill had moved
through the system.
Information Type report
Regional Watershed Howe Sound & Sunshine Coast
Sub-watershed if known Cheakamus River
Aquifer #
Project status complete
Contact Name
Contact Email