Water Quality
Preserving the integrity of our marine environment
What is water quality and why is it important?
Water quality is defined in terms of the chemical, physical and biological properties of water. Water quality can be affected in many ways, often by natureâs own processes, but also by human activities occurring in and adjacent to it. Poor water quality can adversely affect human and ecosystem health.
PRPAâs Marine Environmental Water Quality (MEWQ) program provides an understanding of the state of the water in the Prince Rupert harbour and surrounding area. By knowing the condition of the water and the processes and activities that affect it today, PRPA can make effective management decisions to ensure the integrity of this critical resource now and into the future.
How is water quality measured?
PRPAâs MEWQ program involves many regional partners and stakeholders that contribute to program costs such as sample analysis and reporting. PRPAâs environmental team conducts water quality monitoring in two ways â by collecting monthly in situ (or âon siteâ) measurements as well as quarterly water samples that undergo laboratory analysis.
Quarterly water sampling involves collection and analysis of discrete samples collected at 24 sites throughout the Prince Rupert harbour and surrounding area using a Niskin sampler. These samples are analyzed for parameters including turbidity and total suspended solids, nutrients, metals, phytoplankton abundance (via chlorophyll a concentrations), bacteria, and hydrocarbons. Monthly in situ âdepth profilesâ are also taken of other common parameters such as dissolved oxygen, temperature, and salinity, using an AML-6 CTD (conductivity, temperature, depth) instrument, and alongside the quarterly sampling at the same 24 sites. The instrument is slowly lowered through the water column to each siteâs maximum depth as it records measurements of each parameter. Depth profile data collected since January 2024 is publicly available and can be viewed through Ocean Networks Canadaâs Community Fisherâs geospatial map.
How are water quality measurements interpreted?
For reporting purposes, water quality results are compared to standards developed by both the federal and provincial government, referenced below. PRPA also utilizes the CCME Water Quality Index to categorize annual results for each site as âexcellentâ, âgoodâ, âfairâ, âmarginalâ, or âpoorâ.
In addition, water quality is measured real-time at two underwater observatories â Digby Island and Atlin Terminal â established in 2017 and managed by Ocean Networks Canada. Data can be viewed on the Oceans 3.0 platform here.
How are water quality measurements interpreted?
For reporting purposes, water quality results are compared to standards developed by both the federal and provincial government. PRPA also utilizes the CCME Water Quality Index to categorize annual results for each site as âexcellentâ, âgoodâ, âfairâ, âmarginalâ, or âpoorâ. The map below shows the most recent Water Quality Index scores for each site in the program.
