Sqwa:la (Hope Slough) watershed: Water quality report for the 2024 dry season

Executive summary

Water is essential for life, and steps are needed to understand, protect and restore its health in fish habitat throughout British Columbia. The Raincoast Healthy Waters program was launched in 2023 to establish community-oriented water pollution monitoring in select BC watersheds. Two Healthy Waters sampling events take place every year in each watershed, the first in the dry season (summer), and the second being in the wet season (winter). This report highlights results from the first dry (summer) season sampling carried out with the support and participation of Pelólxw Tribe. 

Briefly, the Healthy Waters – Pelólxw Tribe team determined basic water properties (temperature, conductivity, pH, dissolved oxygen and turbidity) in situ at sampling sites on August 1, 2024. Water samples were collected from four water categories, including source water (3 samples), stream and river water (3 samples), road runoff (3 samples), and Fraser River water (3 samples). The samples were pooled into composites by category and then analysed for coliform, nutrients (6), physical parameters, metals (37), pesticides (62), polycyclic aromatic hydrocarbons (PAHs; 76), pharmaceuticals and personal care products (PPCPs; 141), polychlorinated biphenyls (PCBs; 209), alkylphenol ethoxylates (APEs; 4), bisphenols (BPs; 6), per- and poly-fluoroalkyl substances (PFAS; 40), and sucralose. Analysis of 6PPD-Quinone is pending. 

We detected 104 contaminants out of 587 measured in the stream and river sample collected within the Sqwa:la watershed, excluding nutrients, fecal coliform and physical parameters. Overall, the Sqwa:la (Hope Slough) watershed had relatively good water quality in the dry season, but additional sampling and analysis will provide insight into contamination impacts from forest fires, domestic wastewater, industrial chemicals and runoff (roads, agriculture) on the health of this valued watershed.

Sqwa:la (Hope Slough) watershed

Key findings

• This assessment of water quality in the Sqwa:la watershed reflects the second of several site visits; our understanding of water quality in these watersheds will grow with additional sampling over the coming two years (2025-26).
• We collected and analysed water in the Sqwa:la watershed during the dry season (August 1, 2024).
• The road runoff sample was the sample was the most contaminated water category in the dry season; it had the highest concentration of E. coli, metals, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), pharmaceuticals and personal care products (PPCPs), per- and polyfluoroalkyl substances (PFAS), sucralose, nitrate, and pesticides. 
• Stream and river water was the least contaminated water category in the dry season.
• Concentrations of E. coli and pesticides were notably higher in the dry season compared to the previous wet season sampling. 
• Concentrations of sucralose, and PPCPs were notably higher in the previous wet season sampling, compared to the current dry season. 
• Overall, the Sqwa:la watershed had fair water quality in the dry season.
  • There were seven exceedances of Canadian Environmental Quality Guidelines.
  • There were two exceedances of the Recreational Use Guidelines set by Health Canada (>235 CFU/100ml) in the stream and river, and road runoff samples.

Background

Raincoast’s Healthy Waters Program delivers high-resolution, community-oriented water quality analysis to watersheds across southern British Columbia. The goal of Healthy Waters is to empower communities with the understanding of the status of water quality in their watersheds, to allow for local advocacy regarding both point and nonpoint source pollution. 

The Pelólxw people hold profound relationships with the sloughs, islands and river that connects them. The inherent jurisdiction and title of the Pelólxw Tribe people, to the Hope Slough can be traced back to the time of the eternal ancestors who established the ancient connection between the peoples and their territories. 

Pelólxw Tribe are currently undertaking a major restoration project at Sqwa:la (Hope Slough), which includes increased water quality monitoring in line with Raincoast’s Healthy Waters program. 

The wider restoration project, titled Shxwlístexw te Sqwá:la Shxwelí (Care for the Life Spirit of the Hope Slough) encompasses five pillars to support the health of Sqwá:la and the surrounding communities. The five pillars are as follows: 

1. Improved flow through Sqwa:la
2. Riparian area restoration
3. Fish habitat restoration
4. Water quality monitoring
5. Community and youth engagement

A watershed based approach to sampling

We collect samples from five different categories of water in each of our partner watersheds: from source water, upstream of human impacts, down to the marine environment. Collectively, the lessons learned from our partnering watersheds will contribute to a greater understanding of threats to water quality across British Columbia, and ultimately what policy changes can be implemented to preserve the quality of water for the future of salmon, whales, and people.

Source water serves as an upstream reference sample, allowing us to determine which contaminants are being introduced as water traces its path down through the watershed. 

Stream and river samples allow us to investigate the quality of fish habitat directly, by collecting samples from streams, creeks, and rivers used by salmon and other fish species (either currently or historically). 

Road runoff serves as an impacted sample category of current concern, as many contaminants, including  PAHs, metals, surfactants and chemicals such as 6-PPD quinone can be washed off roadways and into fish habitat during rain events. 

We include tap water samples in our analysis as a way to bring our homes into the conversation – we borrow water from the environment in the form of municipal or well water, and generally return it to aquatic habitats in a more-degraded state in the form of storm and sewage effluent (treated or untreated).

Marine water samples provide insight into those contaminants that may degrade fish and whale habitat in the ocean, and enable an understanding of the contribution of land-based pollutants from the adjacent watershed to the marine environment.

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