Surface Water Quality

This Web site describes water quality conditions in Alberta's lakes, rivers, reservoirs and wetlands. An overview of historic and current data is provided, as well as instructions for those wishing to obtain more detailed information. We hope that you find this site useful and interesting, and we welcome your suggestions for improvement
at AENV-Web.SWQ@gov.ab.ca.

The science of water quality is practiced by a variety of professionals including biologists, chemists, and engineers, and is supported by many technologists. Government agencies and university researchers have conducted much of the scientific investigation in the past, but watershed groups, industries and municipalities are now active partners in many studies. We encourage you to learn about water quality issues in Alberta and become active in protecting our valuable water resources.

What is Surface Water Quality?

There is no single or simple measure of water quality. Surface waters naturally contain a wide variety of substances, and human activities inevitably add to this mixture. Scientists have therefore developed specialized approaches to measuring quality. A single water sample may be tested for a few substances, or for a few hundred, depending on the issues at hand. Samples may be collected by traditional methods, i.e., by filling a container of water in the field then returning it to the laboratory for analysis. Or, data may be collected automatically by installing electronic devices directly into watercourses. These specialized sensors can transmit information via satellite telemetry to office computers within a few minutes of collection. Scientists also study aquatic organisms and the bottom sediments of lakes and rivers to indicate the overall quality of freshwater systems.

Water quality measurements fall into three broad categories:

• physical characteristics such as temperature, colour, suspended solids and turbidity;
• chemical characteristics such as nutrients, minerals, metals, oxygen, and organic compounds;
• biological characteristics such as the types and quantities of aquatic plants, animals, algae, bacteria and protozoan parasites.

Surface water quality data collected by Alberta Environment are stored in an extensive database. Municipal and industrial data collected by Alberta Environment are also included in this system.

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How is Surface Water Quality Evaluated?

Water quality measurements are compared against scientifically derived criteria, known as guidelines. If the measurement is within the guideline value, it is deemed to be acceptable.

Different guidelines are developed to protect the various uses of water. In Alberta, surface water quality guidelines have been established to protect:

• aquatic life
• agricultural uses (stock watering and irrigation)
• recreational and aesthetic purposes

So, the final evaluation of water quality depends on its ultimate use, although the requirements for protecting aquatic life are usually the most stringent.

A single variable or substance may have different numerical guidelines for different uses. For example, the acceptable amount of fecal coliform bacteria in water used for irrigating vegetable crops is different from the guideline that is applied to waters used for swimming and boating. Fecal coliform bacterial levels are not usually a direct concern for the protection of aquatic life; therefore, there is no guideline established for this particular use.

Note that drinking water isn't one of the uses mentioned. That's because surface water is assumed to be unsafe to drink unless it is treated. Even the cleanest-looking mountain stream could contain naturally occurring parasites. Once surface water is treated, it can be evaluated against the Canadian Drinking Water Guidelines. Of course, the cleaner the water is to begin with, the easier it will be to treat.

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What Influences Water Quality?

The climate and landscapes of Alberta have a significant influence on natural water quality conditions. Factors such as vegetation, geology and hydrology cause surface water quality to vary extensively. Swift-moving mountain streams have different chemical, physical and biological characteristics than slower-moving prairie streams. Similarly, the freshwater lakes of the Canadian Shield region in northern Alberta are different than the saline lakes found in the central and southern parts of the province.

Human activities affect the quality of our water. The greatest impacts are usually those associated with the disposal of treated wastewater (from municipalities and industries) into waterways. These discharges, referred to as point sources, arise from a single defined location or facility. Significant and ongoing improvements to waste treatment technology have reduced the impact that this type of pollution has had in recent years.

Water quality is also affected indirectly by our activities on the land. Rain and snowmelt can move materials from the land surface into adjacent watercourses. Therefore, activities such as logging, agriculture, and even urban development within a drainage basin can have a definite impact on water quality. In an urban environment, this non-point source pollution finds its way to the river through city storm drain networks. Chemicals like pesticides or fertilizers that you have applied in your yard could potentially be washed into the river via this pathway.

Certain pollutants originating from urban, industrial or agricultural activities can be transported long distances by atmospheric processes and deposited directly onto surface waters or within their drainage basins. Acid rain is one of the best-known examples of this type of impact.

The quantity of water available also affects quality. The less water there is, the lower the capacity to dilute and assimilate wastes. Climate change and increased consumptive demands may affect water quality in the future by reducing river flows.

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How is Water Quality Protected?

Alberta Environment's mandate to protect water quality is determined by the Alberta Environmental Protection and Enhancement Act (EPEA) and by the Water Act. Under EPEA, the department regulates industrial and municipal discharges to surface waters, and approvals are required. These approvals take into consideration the protection of water quality. Other activities are managed by adherence to Codes of Practice.

Non-point source pollution control remains a challenge, in the sense that no single agency or level of government has sole responsibility for the integration of land use activities into water quality protection strategies. Co-operation between agencies, industries, municipalities and all other stakeholders is required to ensure that this important aspect of water pollution is understood and integrated into the protection of our waterways.

Alberta's new Water Act specifies that Water Management Plans can be developed for rivers and lakes and that protection of the aquatic environment is to be specifically addressed in these plans. The Act encourages planning both at the drainage basin scale and in smaller zones.

In the cases where rivers flow from one province to the next, trans-boundary agreements are in place to ensure that adequate quality and quantity are maintained. Examples of trans-boundary agreements include the Prairie Provinces Water Board (PPWB) Master Agreement on Apportionment (for east-flowing waters) and the Mackenzie River Basin Transboundary Waters Master Agreement (MRBB) (for north-flowing waters).

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Trends and Issues

• Pharmaceuticals in Treated Municipal Wastewaters (Fact Sheet), (Report)
• Pesticides in Surface Water (Fact Sheet), (Report)
• Water Quality Trends: North Saskatchewan River (Report)

Where were we? Where are we going?

Scientists use water quality data collected during intensive monitoring and research programs to assess the effectiveness of water quality protection strategies.

• Surface water quality assessments have been conducted on lakes and rivers in Alberta since the 1940s. Initially, the work focussed on basic inventories to describe the state of fisheries and water resources in Alberta.
• During the 1950s and 1960s, problems caused by excessive nutrients (phosphorus and nitrogen) and oxygen-demanding substances entering the aquatic environment, primarily from municipal and industrial sources, were of great concern. More systematic data collection programs were implemented in the late 1960s; many of these are still in place today, providing a useful long-term record of the state of our waterways.

• Following the creation of Alberta Environment and the development of provincial legislation for regulating point-source discharges in the 1970s, field studies expanded to include non-point source issues associated with logging, agriculture, mining, urban runoff and atmospheric deposition.
• In the 1980s and 1990s, concerns about the general health of aquatic ecosystems, as reflected by the presence of minute quantities of toxic substances in various ecosystem components (animals, plants, sediments, water) began to emerge. The tendency for some contaminants (e.g., pesticides and other organic compounds) to bio-accumulate and pose direct concerns for human health was recognised and continues to be a concern.
• In addition, concerns are turning to the presence of pharmaceutical products (including hormones and antibiotics), pathogens (viruses, bacteria, protozoans) and new agricultural chemicals in aquatic ecosystems. Potential sources include large urban areas and intensive agricultural operations.
• The determination of minimum in-stream flow requirements to protect water quality, particularly in southern Alberta, is now a major focus of work.
• Lake management is also a growing area of interest in Alberta, and many watershed studies have been conducted to assess nutrient impacts.

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