Blue-green algae are making a scene
Facts about algae in surface water
What are the risks associated with blue-green algae in Alberta?
Where did this concern about blue-green algae come from?
Blue-green algae (cyanobacteria) produce toxins that are harmful to humans, livestock, pets, and wildlife, causing illness and, in rare cases, death. Blooms often produce a distinct taste and odour, and are a nuisance and health hazard for many ranchers, boaters, swimmers, and other surface water users.
Given the disturbance algal blooms cause to water bodies, they are sometimes mistaken for an invasive species. Though blooms occur naturally they can have negative consequences on aquatic ecosystems, which are heightened as blooms get larger and become more frequent.
When the mass of algae eventually dies, it decomposes, using up valuable dissolved oxygen and disrupting other natural processes. When dissolved oxygen is too low, fish and aquatic organisms may struggle to survive.
Managing algal blooms is important for the entire aquatic ecosystem and for land based water users including livestock, wildlife, and humans. While problematic for water quality, algal blooms (including those due to blue-green algae) are a natural phenomenon in Alberta that is often accelerated by human induced factors.
What is the science behind blue-green algae (cyanobacteria) blooms?
Blue-green algae occur naturally in surface waters and there are more than 100 species in Alberta, ranging in size and shape.
When optimum surface water conditions are reached, the organism can reproduce rapidly forming a “bloom.” Conditions that promote growth include warm temperatures, sunshine, slow-moving water, and high levels of nutrients.
Not surprisingly, the most common time for algal blooms in Alberta is July to September when air temperatures are high, the sun is shining, and water levels are low.
While these conditions occur naturally during the summer, regardless of human interaction with the surface water, it is the unnatural loading of phosphorus into lakes that accelerates algal growth.
Algal blooms have been linked to human presence ever since phosphorus addition to surface waters was identified as a key contributor to excessive algal growth. Phosphorus is an essential element for plant growth, and while it is found naturally in decaying organic matter, rocks, and soils, it is also a common ingredient (and is present in much greater concentrations) in fertilizer and household cleaning products.
Runoff from urban and agricultural areas transports phosphorus from fields and soils to rivers and ponds, septic fields contribute effluent to shallow groundwater, and wastewater treatment plants in urban areas release treated wastewater into rivers.
Nitrogen is another key nutrient found in wastewater and fertilizers and, once in the aquatic environment, further boosts the growth of aquatic plants including blue-green algae.
What is being done about blue-green algae?
Blue-green algae are a natural part of the Bow River Basin ecosystem. Management goals are not focused on eradicating blooms completely, but rather limiting the excessive growth of unnatural blooms caused primarily by high phosphorus loading to water bodies from human activities.
In the Bow River Basin, about 21% of phosphorous in the Bow River comes from point sources such as wastewater treatment plants, while non-point sources like stormwater runoff, irrigation, and stream bank erosion account for about 78% during open water season. Point sources can be more straightforward to manage than non-point sources, because it is easier to locate the source of loading, but this would only address a small part of the problem. Runoff and non-point sources typically involve far more people across a much greater spatial and temporal scale, but collectively these sources contribute the most phosphorus loading. Conversations about how to reduce phosphorus loading to rivers, and consequently reduce algal blooms, must include each of the many stakeholders to find a collective solution.
To manage phosphorus loading to surface waters, Alberta Environment released an interim policy on effluent limits in 2008. Following this policy, Alberta Sustainable Resource Development brought together a diverse group of stakeholders to address phosphorus loadings in the Bow River, from point and non-point sources throughout the basin. Government and non-government representatives, both urban and rural, came together to develop the Bow River Phosphorus Management Plan released in 2014. The plan defines the issues and proposes strategies and actions for managing phosphorus in the Bow River. Through its implementation, this plan will create a model for other areas suffering from excessive phosphorus and troublesome algal blooms.
Additional measures taken by the Government of Canada include limits on phosphorus in laundry detergents, which have been in place for decades, as well as a 2011 ban on the use of phosphates (the problematic form of phosphorus) in dishwasher detergents. These measures help reduce phosphorus loading from municipal wastewater effluent point sources. Reduction of phosphorus in wastewater effluent, a point source in the river, is an ongoing area of research, and best practices continue to be updated and implemented whenever possible. However, non-point sources such as urban and agricultural runoff remain high in both phosphorus and nitrogen and continue to be major contributors to algal blooms across the country.
Short term chemical control of algae is prohibited and creates additional issues for natural lakes, so it is well accepted that longer term regional solutions to reduce nutrient loadings to surface water will be key for managing algal blooms.
To minimize the risk to human health from direct exposure, Alberta Health Services posts active blue-green algae advisories online in addition to signage around lakes known to experience or be experiencing elevated levels of algal blooms. This helps protect lakeside visitors from potential exposure to the algae and their associated health impacts.
What can I do about blue-green algae?
Limiting nutrients entering the water helps reduce the possibility of blue-green algae blooms. Reducing fertilizer use and using holding tanks instead of septic fields near lakes are some ways to minimize contributions to surface waters.
Choosing cleaning products with lower phosphorus levels and avoiding the use of fertilizers on your lawn will also reduce the nutrient runoff to streams and rivers.
Best management practices for agriculture and ranching operations are available through Alberta Agriculture, such as grassed waterways and buffer strips to manage nutrient loading to ponds and dugouts.
When blue-green algae advisories are in effect, it is best to avoid all contact with the bloom. Wading and swimming in areas of a water body with blue-green algae could cause skin and eye irritation. Alberta Health Services recommends not eating fish from the lake or feeding it to pets.
Drinking or cooking with water from the lake is not recommended, especially since boiling the water will not remove toxins produced by blue-green algae. If contact with a bloom occurs, showering with clean water as soon as possible can reduce effects of skin exposure.
Sources and additional information
Alberta Environment and Parks. (n.d.). Cyanobacterial Blooms and Toxicity. http://aep.alberta.ca/water/programs-and-services/surface-water-quality-program/documents/CyanobacterialBloomsToxicity.pdf
Alberta Environment & Sustainable Resource Development. (2014). Bow River Phosphorus Management Plan. Retrieved from http://esrd.alberta.ca/focus/cumulative-effects/cumulative-effects-management/management-frameworks/documents/BowRiverPhosphorusPlan-Jun06-2014.pdf
Alberta Health Services. (n.d.). Frequently asked questions: Blue-green Algae (Cyanobacteria). Retrieved from http://www.museumsassociation.org/about/frequently-asked-questions
Canada moves to cut phosphates to fight algae problem. (2008). Retrieved June 22, 2017, from http://www.cbc.ca/news/canada/montreal/canada-moves-to-cut-phosphates-to-fight-algae-problem-1.744071
Detergent change makes for dingy dishes. (2011). Retrieved June 22, 2017, Retrieved from http://www.cbc.ca/news/canada/edmonton/detergent-change-makes-for-dingy-dishes-1.1015028
Elger, S. (2015). Blue-Green Algae (Cyanobacteria) in Surface Water Sources for Agricultural Usage. Retrieved from: http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/wqe15283/$file/blue-green-algae.pdf?OpenElement
Koning, C. W., Camm, E., & Kerr, J. (2017). Water Quality and Phosphorus. Bow River Phosphorus Management Plan.
Do you feel mis-LEAD by your water?
Facts about lead in tap water
There might be lead in tap water, exposing consumers to serious health risks.
Where does the concern about lead in tap water come from?
Recent major incidents have drawn attention to the presence of lead in drinking water. For example, in 2016, an Edmonton woman suffered health effects from elevated lead in drinking water coming from the tap of her 70-year-old home. In 2014 in Flint, Michigan the switch to a corrosive water source caused widespread leaching of lead into the drinking water.
The issue of lead in Alberta drinking water arises from the use of lead prior to the 1960s in service connections from water mains to individual houses and housing complexes with up to eight units. When water flows through pipes that contain lead, this heavy metal can dissolve, or leach, into the water.
The presence of lead in drinking water is a concern because lead is a neurotoxin, meaning it can affect brain development in humans, especially fetuses, infants and young children. Lead can also negatively affect cardiovascular, kidney, and reproductive systems even at very low concentrations. Since it has no taste, colour, or odour, it is possible for individuals to unknowingly consume lead in drinking water. This, combined with lack of information on the building materials used in a home may result in concerns.
What is the science behind lead leaching into tap water?
Lead dissolves from pipe materials, including joints and solder, due a chemical reaction between the water flowing through the pipes and the pipe itself. Once water leaves a treatment plant it may encounter lead in:
- Older distribution mains and utility-owned or private service lines, and
- Service connections from pipe jointing compounds, soldered joints, and brass fixtures.
Several factors can also increase the likelihood of lead leaching into tap water, such as:
- The condition of the pipes and fittings containing lead, particularly how corroded they may be,
- Whether lead-containing solder is used in connections between new copper and old lead pipes,
- The amount of lead in pipes or connections,
- Whether pipes have protective coatings or natural scaling,
- The residence time of water in pipes that contain lead, and
- The temperature and chemistry of the water, including its acidity and its mineral content; i.e., whether it is soft or hard water.
In the 1950s and 60s, new plumbing installations started to use different materials, such as copper and plastic, rather than lead. However, stories of lead poisoning from drinking municipal tap water continue to appear in the news as the transition remains incomplete and some older homes and neighbourhoods still have lead pipes.
The use of lead for water service lines was permitted by the National Plumbing Code of Canada until 1975, while lead solder was permitted until 1986. Solder containing lead for drinking water supplies was prohibited under this code after 1990.
What is being done about lead in tap water?
Canadian federal, provincial, and municipal governments work together to mitigate the risks associated with lead pipes through:
- National building standards and codes,
- National and provincial water quality guidelines, and
- Municipal programs for water testing, filter installation and pipe replacement assistance.
Standards and codes aim to ensure new construction does not introduce lead contamination risks into municipal water supply systems and that treated water does not contain hazardous substances like lead.
Other guidelines and programs protect consumers from existing sources of lead contamination until the area is redeveloped or the homeowner or utility provider replaces components that contain lead.
Alberta has adopted the Canadian Drinking Water Guidelines, which specify the maximum allowable concentration of lead in drinking water (0.010mg/L). Drinking water that leaves the water treatment plant must adhere to these guidelines, and is tested for compliance at monitoring points throughout the water supply network. Due to the size of most water supply systems, testing at every tap is impractical, however municipal programs offer tap water testing for homes with suspected lead exposure. For instance, EPCOR (Edmonton’s water utility service provider) provides annual notification to residents of homes that are known to have lead service lines and offers complimentary tap water testing for lead.
Since the issue with lead is due largely to the presence of old piping, a key way of addressing the risk is to replace those pipes with newer ones that do not contain hazardous substances like lead. This means that it is essential for cities and homeowners to have good information about their plumbing and water servicing.
There is no national database for homes that still have lead pipes in Canada, but individual municipalities can often provide information on the status of lead piping in their communities. For example, the City of Calgary has identified 630 customers with lead service connections, and offers services such as water quality testing, education and a rebate for filtration devices. In areas where utilities do not provide this service, laboratory testing through public health offices is generally available to help determine if there is a risk of lead being present in drinking water.
What can I do about the possibility of lead in tap water?
If you are concerned about the possibility of lead in your household tap water, there are several steps you can take.
- Determine whether your house has lead pipes
- Contact your water utility provider or municipality and ask for records of lead service lines in your community, or
- Enlist a plumber or home inspector to identify whether pipes contain lead.
- If your house has lead pipes, have your tap water tested for lead concentration. In Alberta, there are three ways to do this:
- Contact your local water utility to see if they offer lead testing in homes with known lead service lines,
- Arrange for laboratory testing through a local public health office. Visit the Alberta Health website to find service locations, or
- Arrange for laboratory testing through private, accredited laboratories (at your own expense).
Alberta Health recommends various actions depending on the results of the lead test and the age of those consuming the water. Please refer to the following document for detailed information.
“Lead and Drinking Water from Lead Service Lines (2013): Guidance package for Water Utility Companies, Residents, Alberta Health Services, Healthcare Providers, and Laboratories” published by the Alberta Office of the Chief Medical Officer of Health.
Sources and additional information
Calgary Water Services. (n.d.). Lead monitoring in Calgary’s water. Retrieved April 28, 2017, from http://www.calgary.ca/UEP/Water/Pages/Drinking-water/Water-quality/Lead-Service-Connections.aspx
Flint Water Advisory Task Force. (2016). Final Report. From https://www.michigan.gov/documents/snyder/FWATF_FINAL_REPORT_21March2016_517805_7.pdf
Health Canada. (2009). Lead Information Package – Some Commonly Asked Questions About Lead and Human Health. Retrieved July 5, 2017, from https://www.canada.ca/en/health-canada/services/environmental-workplace-health/environmental-contaminants/lead/lead-information-package-some-commonly-asked-questions-about-lead-human-health.html
Health Canada. (2013). Final Human Health State of the Science Report on Lead. From https://www.canada.ca/en/health-canada/services/environmental-workplace-health/reports-publications/environmental-contaminants/final-human-health-state-science-report-lead.html
Prévost, M. (2013). Lead in Tap Water: Assessing Consumer Exposure and Identifying Corrective Actions, Canadian Water Network. PUBLISHED: 25 JANUARY 2018
Facts on fluoride
Facts about fluoride in tap water
What are the risks of not enough or too much fluoride in tap water?
Where does the concern about fluoride in water come from?
Water with low fluoride concentrations has beneficial effects on teeth, preventing and controlling tooth decay in children and adults. However, too much fluoride can cause adverse health effects.
The major concern with adding fluoride to drinking water is dental fluorosis, a condition that changes the appearance of tooth enamel. Although a large body of scientific evidence from credible sources exists on the relationship between health and fluoride, stories of adverse health effects from media and interest groups have caused widespread concern that is largely unsupported by scientific studies.
What is the science behind fluoride in drinking water and its potential health effects?
Fluoride occurs naturally in water as it leaches (dissolves into water) from rock formations, or is introduced via human activities like chemical, steel, glass and cement manufacturing.
Because fluoride is a naturally occurring mineral it is found in low levels in most drinking water sources in Canada.
Depending on the water’s natural levels of fluoride, treatment plants may either add fluoride to obtain benefits for oral health or treat the water to reduce the level of fluoride to meet federal and provincial requirements for safe drinking water.
The maximum allowable limit set out by Canadian Drinking Water Guidelines, to which Alberta adheres, is 1.5 mg/L. In some parts of the world, due to specific geologic formations fluoride levels can reach 57 mg/L, resulting in elevated occurrence of skeletal and dental fluorosis.
Skeletal fluorosis occurs when fluoride accumulates in bones, causing a non-life-threatening disease in which bones increase in density and become brittle due to structural changes from addition o fluoride. Case studies of crippling skeletal fluorosis from North America are extremely rare, and all include as a likely cause the long-term consumption of drinking water with elevated concentrations of fluoride (2.4-7.8 mg/L), well above the maximum allowable concentration set out by Health Canada of 1.5 mg/L.
Only children whose teeth are developing under the gums are at risk of developing dental fluorosis and only at concentrations higher than the Health Canada guideline limit of 1.5 mg/L.
A Health Canada review of available science, supported by the 2007 Health Canada expert panel, concluded the amount of evidence behind other purported health effects, such as cancer, IQ deficiency, bone fractures, and developmental toxicity does not support a link between fluoride exposure at Canada’s maximum allowable limit of 1.5 mg/L and any of these adverse effects.
What is being done about fluoride in drinking water?
Municipal treatment plants that provide drinking water to consumers must follow the Canadian Drinking Water Quality Guidelines, ensuring water leaving the plant does not exceed the fluoride limit.
Approximately 87% of the population relying on the Bow River or its tributaries for source water are serviced by City of Calgary Water Services. In a 1989 plebiscite, Calgarians voted in favour of adding fluoride to the city’s drinking water. By 1991, fluoride was being added at a targeted level of 1.0 mg/L. In 1998, the City and Alberta Health Services reviewed water fluoridation as a public policy, and a panel of five experts recommended a reduction in the level of fluoride to 0.7 mg/L. This change was adopted in 1999 following a second plebiscite where Calgarians again voted 55% in favour of fluoridation. The City of Calgary discontinued the addition of fluoride to city drinking water as directed by Council on May 19, 2011.
What can I do about fluoride in drinking water?
Municipality or utility service providers are bound by regulation to adhere to the maximum allowable concentration of fluoride in drinking water as outlined in the Drinking Water Quality Guidelines. Some municipalities choose not to fluoridate their water at all, a decision based on either Council vote or natural fluoride concentrations of the source water.
Contact your drinking water provider, utility services provider or local municipality to find out more about their fluoridation practices. Private drinking water sources, such as groundwater wells or springs, can be tested for fluoride concentrations through accredited laboratories to determine fluoride levels. Talk to your dentist or doctor if you are concerned about any of the potential health effects from fluoride in your water.
Sources and additional information
Patterson, S.K. (2010). A Review of Water Fluoridation. Alberta Health, Office of the Chief Medical Officer of Health.
Dental Health Services Victoria. (n.d.). People without fluoride in their drinking water. Retrieved July 5, 2017, from https://www.dhsv.org.au/dental-advice/general-dental-advice/people-without-fluoride-in-their-drinking-water
Fawell, J., Bailey, K., Chilton, J., Dahi, E., Fewtrell, L., and Magara, Y. (2006). Fluoride in Drinking-water. World Health Organization. https://doi.org/10.1007/BF01783490
Fluoride in Calgary’s water (n.d.) http://www.calgary.ca/UEP/Water/Pages/Drinking-water/Fluoride.aspx
Health Canada. (2010). Guidelines for Canadian Drinking Water Quality: Guideline Technical Document – Fluoride. Water, Air and Climate Change Bureau, Healthy Environments and Consumer Safety Branch, Health Canada. Ottawa, Ontario. Retrieved from http://healthycanadians.gc.ca/publications/healthy-living-vie-saine/water-paraquat-eau/alt/water-paraquat-eau-eng.pdf
National Health and Medical Research Council. (2007). A systematic review of the efficacy and safety of fluoridation part a: review methodology and results. PUBLISHED: 23 JANUARY 2018
Get the scoop on fecal coliforms
Facts about fecal coliform warnings in surface waters
What are the public health risks associated with fecal coliforms?
Where does the concern about fecal coliforms come from?
Water quality advisories issued by the Province of Alberta, as a measure to protect public health and safety, often quote elevated levels of fecal coliforms as the main reason to avoid contact with the water body for which the advisory has been issued.
Advisories warn water users not to swim in or drink the water due to a list of potential negative effects from exposure to water-borne organisms, including fecal coliforms. Based on this information, which contains few details on the organisms themselves, it is a reasonable conclusion that fecal coliforms are harmful and any water with a fecal coliform warning poses a serious health risk.
That said, there is more to the science and people often raise questions to better understand the risks like: How serious is the risk from coliforms? Are certain coliforms more harmful than others? Does boiling water completely remove the risk? Is all E. coli toxic?
What is the science behind fecal coliform warnings?
Coliforms are a collection of bacteria that includes fecal coliforms. They originate from animal digestive tracts, animal waste, and other natural and man-made decomposition processes (e.g., waste treatment). Fecal coliforms occur naturally in the lower digestive tract, but can be harmful under certain exposure situations.
Various types of coliforms are used as indicators of microbial contamination in water in the following ways:
- Total coliform counts indicate how many bacteria within that collection are present in a sample, and are often used as indicators of potential contamination with fecal waste (sewage and manure) from either humans or animals. Sometimes total coliform counts are used as indicators of non-sewage pollution. Because they are the largest set of coliforms used to assess fecal contamination, they are generally reported as a validation of the analysis conducted.
- Fecal coliforms are a sub-group of total coliforms found in the intestinal tract of warm blooded animals and their presence can indicate higher likelihood of contamination with sewage (fecal pollution). Despite greater potential as an indicator of sewage contamination, some members of the fecal coliform group have been found in the absence of recent contamination.
- Escherichia coli (E. coli) is one species of fecal coliform generally not found growing and reproducing outside an intestinal tract. Therefore, presence of E. coli is used as an indicator of definite contamination with fecal matter. Waste from any warm-blooded animal can contain E. coli, including cattle, poultry, beavers, deer, waterfowl and humans.
Figure 1: Relationship between total coliform group, fecal coliform group, and E. coli.
Adapted from Verhille, S. (2013) Understanding microbial indicators for drinking water assessment (Figure 1).
Not all fecal coliforms themselves are considered pathogenic, or disease-causing, however the routine methods for analysing coliforms cannot easily discern between harmful and benign species.
In cases where fecal contamination has caused serious illness it is due to the presence of pathogenic strains of bacteria, such as E. coli 0157:H7, which was the culprit in a Walkerton tainted water case in Ontario.
The real issue is that water containing fecal coliforms may have been in contact with fecal matter, which increases the risk of it containing other bacteria, viruses and enteric protozoa.
These disease-causing organisms, such as pathogenic strains of E. coli, Salmonella, Giardia and Cryptosporidium (see Microorganisms and Pristine Headwaters ) and many other microbes are the real concern when there is potential or confirmed contamination of water with feces.
Since there is no single, common microbial indicator that can represent all potential pathogens, casting a wide net for fecal coliforms provides an opportunity to flag water that is potentially contaminated and needs to be treated with additional processes before consumption.
What is being done about fecal coliforms and E. coli?
The Environmental Public Health Department of Alberta Health Services is responsible for sampling and inspecting public water supplies, as well as issuing water advisories when required.
This department checks specifically for E. coli and total coliform bacteria in drinking water through the Provincial Laboratory of Public Health, Environmental Microbiology Services. Alberta Environment and Parks (AEP) is responsible for monitoring water quality of lakes and reservoirs, and will issue advisories for fecal coliforms through Alberta Health Services.
What can I do about fecal coliforms?
Checking with AHS for active Health Advisories is a simple way to decrease the risk of illness from contact with contaminated water. The advisories specify what activities are not recommended and for which water body, and always prioritize public health and safety.
Although the Government of Alberta monitors for fecal coliforms in lakes and reservoirs, there are too many for each one to be tested frequently enough to guarantee that no contamination exists. Water quality data and sampling locations are stored in AEP’s central Water Data System, which can be accessed through the Alberta Environment and Parks website.
Direct consumption of contaminated water used for drinking or cooking presents the highest potential risk to human health, therefore a good rule of thumb is to assume that all surface water is unsafe to drink without prior treatment. There are numerous treatment methods, such as boiling, UV disinfection, chemical disinfection, and filtration, that are all useful for different types of pathogens and potential contaminants.
Sources and additional information
Alberta Health Services. (2016). Contaminated water advisory extended for Elbow River (within the city of Calgary). Retrieved May 5, 2017, Retrieved from http://www.albertahealthservices.ca/news/Page13290.aspx
British Columbia Ground Water Association. (2007). Total, Fecal and E. coli Bacteria in Groundwater. Water Stewardship Information Series (February). Retrieved from http://www.env.gov.bc.ca/wsd/plan_protect_sustain/groundwater/library/ground_fact_sheets/pdfs/coliform(020715)_fin2.pdf
Environment Canada. (2001). Threats to Sources of Drinking Water and Aquatic Ecosystem Health in Canada. NWRI Scientific Assessment Report Series No. 1. Retrieved from http://publications.gc.ca/collections/Collection/En40-237-1-2001E.pdf
Health Canada. (2008). What’s in Your Well? – A Guide to Well Water Treatment and Maintenance. Retrieved May 5, 2017, Retrieved from https://www.canada.ca/en/health-canada/services/environmental-workplace-health/reports-publications/water-quality/what-your-well-guide-well-water-treatment-maintenance.html
Inside Walkerton: Canada’s worst-ever E. coli contamination – Canada – CBC News. (2010). Retrieved October 24, 2017, from http://www.cbc.ca/news/canada/inside-walkerton-canada-s-worst-ever-e-coli-contamination-1.887200
New York State Department of Health. (2012). Coliform Bacteria in Drinking Water Supplies. Retrieved from https://www.health.ny.gov/environmental/water/drinking/coliform_bacteria.htm
Verhille, S. (2013). Understanding microbial indicators for drinking water assessment: interpretation of test results and public health significance. NCCEH Reviews, (Figure 1), 1–12. Retrieved from http://www.ncceh.ca/documents/guide/understanding-microbial-indicators-drinking-water-assessment-revised PUBLISHED: 20 JANUARY 2018
Would you drink this?
Facts about the pristine-looking headwaters
How can I tell if water that looks pristine, like mountain springs or streams, is safe to consume without treatment?
Where did the concern about needing to treat water in the mountains come from?
At first glance, crystal clear water running through mountain streams looks pure and untainted by pollution. This is because the term “pollution” is often associated with industrial effluent, urban and agricultural runoff, and wastewater treatment effluent added to the river by human activities.
High in the headwaters of Alberta’s rivers, one may think the absence of human activities makes the water much safer to drink. Surface water high in the mountains may be far away from any significant form of human disturbance but it is still subject to contamination from wildlife.
What is the science behind the safety of drinking pristine-looking water?
The Government of Alberta puts it simply: assume that any untreated surface water is unsafe to drink.
Parasites, including Giardia and Cryptosporidium, which naturally occur in wildlife feces can easily end up in surface waters and be carried great distances, contaminating reaches of water well downstream of the initial contact. Giardiasis, commonly referred to as beaver fever, is the infection resulting from ingestion of Giardia cysts. Symptoms of giardiasis include diarrhoea, cramps, dehydration and fatigue for up to three weeks after consumption of the contaminated food or water.
Cryptosporidium oocysts are found in fecal matter from humans, livestock, and wildlife. The oocyst is hardy and environmentally stable, allowing it to be transmitted easily from a host organism, such as a wild animal, to humans through water. Direct contact of feces with a water source or introduction via runoff can contaminate lakes, rivers and streams no matter how far they are from human sources of pollution. Symptoms of cryptosporidiosis resemble those of giardiasis, including diarrhoea, fever, and dehydration.
Both Giardia cysts and Cryptosporidium oocysts are too small to be seen with the naked eye. This means even though the water may look crystal clear it could be contaminated with these potentially harmful organisms.
What is being done?
Creating awareness of the risks associated with drinking untreated surface water helps prevent accidental or intentional consumption of contaminated water in the wilderness.
The Canadian Drinking Water Guidelines, which Alberta has adopted, specify removal of both Giardia and Cryptosporidium from drinking water along with a host of other microbial parameters that could cause illness.
What can I do about drinking from pristine headwaters?
As the Government of Alberta states: assume that any untreated surface water is unsafe to drink.
There are methods for treating water upstream of large scale treatment plants, but the consumer is responsible for becoming familiar with which methods are effective at removing each type of potentially harmful waterborne organism.
Water can be treated to kill Giardia cysts through boiling, and certain filtration methods will remove the cysts altogether. Interestingly, standard chlorination concentrations that will kill most other harmful organisms will not kill Giardia cysts.
Filtration and disinfection with UV light are more effective at removing Cryptosporidium oocysts than chlorine treatment, and boiling for at least one minute will also kill Cryptosporidium.
Campers, hikers and other backcountry users should carefully research portable water treatment options.
Sources and additional information
Alberta Environment and Parks. (2015). Surface Water Quality Program. Retrieved May 11, 2017, from http://aep.alberta.ca/water/programs-and-services/surface-water-quality-program/
Alberta Environment and Parks. (2017). Alberta River Water Quality Index. Retrieved July 5, 2017, from http://aep.alberta.ca/water/reports-data/alberta-river-water-quality-index.aspx
Cooke, S., Mitchell, P., Roy, L., Gammie, L., Olson, M., Shepel, C., Chanasyk, D. (2002). Relationship Between Beef Production and Waterborne Parasites in the North Saskatchewan River Basin. Retrieved from http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/wat6400
Health Canada. (2007). Water Talk: Drinking water quality in Canada. Retrieved from http://www.hc-sc.gc.ca/ewh-semt/alt_formats/hecs-sesc/pdf/pubs/water-eau/drink-potab-eng.pdf
Health Canada. (2012). Guidelines for Canadian Drinking Water Quality: Guideline Technical Document – Enteric Protozoa: Giardia and Cryptosporidium. Retrieved from http://healthycanadians.gc.ca/publications/healthy-living-vie-saine/water-enteric-virus-enterique-eau/index-eng.php
University of Alberta. (2014). Giardiasis in Alberta. What’s Bugging Wild Critters? Fact Sheet #37: Giardiasis. Retrieved from http://aep.alberta.ca/fish-wildlife/wildlife-diseases/documents/Giardiasis-Oct-2014.pdf