Fairy Lake

Fairy Lake background

Fairy Lake is located at the headwaters of Black Creek. The lake originated in 1830 when the Adams brothers built a dam on Black Creek to create a mill pond in order to operate a flour mill and a saw mill. Prior to the creation of the lake, the area was historically a wetland. The dam remains in place and maintains the water levels creating the ‘lake’. Fairy Lake is approximately 26 hectares in area and is used for boating, swimming, fishing as well as providing scenic views from various vantage points around the lake (public and private).

The Town has undertaken various studies of Fairy Lake in the past. Most recently the Fairy Lake Water Quality Study was completed in 2010.

Blue-green algae

Blue-green algae is a naturally occurring organism that appears on the water surface as a green paint-like discolouration. It typically blooms in late summer and early fall when temperatures are higher and there are higher nutrient (phosphorous and nitrogen) levels in the water. Blue-green algae is harmful to humans and animals, and it may be present even if not visible. If you see blue-green algae or see warnings posted, you (and your pets) should not drink, swim or wade in the water. Do not eat fish caught in the water.

The Town is looking at different blue-green algae control options. Most studies recommend the same actions being taken as part of the water quality study (buffers, reduced fertilizers, etc.). Blue-green algae may continue to be a problem as the impacts of climate change increase each year. The Town is preparing educational signage to be installed in public access areas of the lake to provide information to the public and will also investigate new technologies used to control the algae. Visit the government of Ontario's website for more information on blue-green algae.

Water quality study

Fairy Lake has been studied many times over the years. The Town undertook a Water Quality Study for Fairy Lake in 2010. The 2010 study identified the following key points:

• Fairy Lake is more like a wetland than a lake, and should be managed accordingly. Shallow water naturally leads to abundant aquatic vegetation which provides habitat for aquatic wildlife, including fish.
• Much of the lake is quite shallow (1m average), although there are deeper areas (7m depth).
• 90% of the water entering the lake is from surface water which tend to have higher nutrient levels. In June and July groundwater contributes 40% of the total water.
• The chemical composition of the lake was highly supportive of aquatic plants. High nutrient levels were found at all sampling locations. High bacteria levels were found on one or more occasions at nearly all testing locations. Temperature and dissolved oxygen levels are common for shallow, productive lakes: substantial volumes of the lake have very low concentrations of oxygen. Some plants and animals are very sensitive to the amount of oxygen in the water and cannot survive when there is not enough.
• The lake bottom was found to be very rich organic soil with high nutrient content and the clear shallow water supports aquatic plant growth.
• There were significant amounts of Eurasian Water Milfoil and Stonewort and various other aquatic plant species; which is consistent with the conclusion that Fairy Lake is actually a wetland and not a true lake.
• Lots of waterfowl were observed on and around the lake. Waste from water fowl can contribute to high bacteria and nutrient levels, and affect water quality.
• Many people are not aware of this study, and the Town is working to provide public education about Fairy Lake.
• As part of the 2021 Water Quality Study, the findings of the 2010 report will be updated and reviewed.

Swimming

The water quality of Fairy Lake is affected by many factors, including run-off, goose waste, stormwater, agricultural run-off, nutrient levels and temperature. At times, the bacteria levels in the lake make it unsafe for swimming. Halton Region’s Health Department tests the water quality weekly at the Prospect Park Beach (June-August).

Weekly results of Halton Region's water quality testing can be found on their website, and residents should look for signage noting beach closures.

Invasive species

There are areas along the edge of the lake that have phragmites (an invasive plant that grows along shores and shallow water), as well as other aquatic invasive plants in other deeper water areas. While these plants are invasive and can impact the natural environment, they also absorb nutrients and may have some positive effect on water quality. For more information, visit our invasive species page.

The Town is working with CVC and contractors to investigate management options for control of invasive species.

Unmaintained vegetation - buffers

One of the recommendations of the Water Quality Study was to provide buffer plantings around the lake. Buffers benefit the lake by absorbing and filtering water before it gets into the lake. 

Most of the buffers are naturalized with native plantings, but there are improvements that could be made by removing invasive species that have grown in the buffer areas. The Town does not plan to remove or stop installing buffers in appropriate locations, but the 2021 Water Quality Study will review the buffers in more detail and look for opportunities to manage the invasive species.

Frequently asked questions

1. I see a lot of weeds in Fairy Lake, is that normal?
   

   The Fairy Lake Water Quality Study (2010) confirmed that Fairy Lake is really a wetland. Because of this, it is normal for there to be some aquatic vegetation in the lake. While some may be invasive, Council approved the Town managing the lake as a wetland and allowing it to naturalize (which is consistent with the Town’s priority focus on climate change). The Town does not have any plans to control aquatic vegetation.

2. Are there any sensitive native plants and animals in Fairy Lake? 

   Blanding's Turtle, a species at risk in Ontario has been found in Fairy Lake. Learn more about the Blanding's Turtle on the government of Ontario website. The Town will be investigating whether there are other species at risk as part of the 2020 review.

3. Is anything being done about the water quality in Fairy Lake? 

   The main recommendations from the Water Quality Study included establishing the naturalized buffers, controlling the goose population, and taking steps to reduce the phosphorous entering the lake from storm sewers. The Town implements buffers where possible and appropriate. The Town also is working with Halton Region on reducing the phosphorous in the Lake as part of the Acton Wastewater Treatment Plant requirements. This includes installing treatment infrastructure at the outfalls along Black Creek, which is expected to improve the overall water quality of Fairy Lake for the phosphorous reduction program being undertaken. Phosphorous levels in water are closely related to water nutrient levels and promote aquatic vegetation growth. Elevated phosphorous levels can also contribute to algae blooms. Phosphorous is commonly found in detergents, and many other household cleaning products. In 2020, the Town plans to undertake supplemental testing to review the current water quality, to compare it to the original results from 2010 and identify if there have been any improvements over the last 10 years. This review will include an analysis of the current water quality, amount/types of aquatic vegetation compared to 2010, and the effectiveness of the various actions taken to date, along with the next steps and actions recommended for management.

4. Can I go boating in Fairy Lake? 

   Non-motorized boats are allowed in Fairy Lake, and during the spring/summer, kayaks and canoes are available for rent at the Boathouse from the Holy Cow Canoe Company. When boating, be aware of the potential for blue green algae and other water quality alerts; take the appropriate precautions, and be sure to rinse off your boat and yourself as soon as possible after your trip.

5. Is there anything I can do to improve the water quality in Fairy Lake? 

   We are all part of the solution. If you own property next to the lake, consider planting a buffer along the edge of the lake or install rain barrels to reduce the runoff to the lake. Have your septic system inspected as leaks in septic systems contribute to poor water quality and increased nutrients in the lake. You can also reduce the amount of fertilizer you use. If you have a dog, make sure you clean up after them and dispose of any waste into appropriate receptacles. Use phosphorous free products whenever possible. Don't feed water fowl, particularly near public use areas.

6. Why doesn’t the Town dredge the lake anymore? 

   Based on the Water Quality Study, the Town decided to manage Fairy Lake as a wetland. This means not dredging the lake which could affect sensitive plants and animal species and disturb the natural habitat. Dredging the lake would also be extremely costly, require extensive regulatory approvals, and would only be a temporary solution, as the lake would fill back in over time. The Town does not have any plans to dredge the lake again. The Town recognizes that this does affect recreational use of the lake, but there are still opportunities to use the lake in its current condition. The Town has also invested in other water features like the Superior Glove Splash Pad in Prospect Park to provide recreational water play opportunities.