Watershed Report Card

What is a watershed?

A watershed is an area of land drained by a creek or stream into a river which then drains into a larger body of water such as a lake. Everything in a watershed is connected, which means that our actions upstream can affect conditions downstream.

What is a watershed report card?

Ontario conservation authorities report on watershed conditions every five years. The report cards use Conservation Ontario guidelines and standards developed by conservation authorities and their partners to provide an overview of watershed health in three key categories:

Forest Conditions for the watershed received an overall rating of D (Poor) because large forest areas are scarce and urban forest areas are small. Most forest in the watershed is found above the Niagara Escarpment in the headwaters of Bronte Creek and Sixteen Mile Creek, where urban development and agricultural activities are limited.  The report identifies that there is a sufficient amount of streamside vegetation that is forested in some areas of the watershed, but more coverage will help improve the health of aquatic and terrestrial ecosystems. 

Groundwater Quality for the watershed is measured at ten well locations and received an overall rating of A (Excellent) based on concentrations of nitrate +nitrite (as Nitrogen) and chloride levels. (Results identify conditions at the wells only.) Two of the wells indicated higher levels of chloride, but both are naturally occurring concentrations because they are located near shale bedrock. Two other wells indicated higher levels of chloride and nitrogen as a result of human activities, such as road salting and agriculture—otherwise, the majority of the monitored wells scored as having “excellent” water quality.  

Surface Water Quality for the watershed is measured based on chemical indicators (ie., phosphorus concentrations) and biological indicators (ie., benthic invertebrates) and received an overall rating of C (Fair). Nine of the 18 sub-watershed areas had more degraded conditions and received a lower grade than in previous years, and nine had improved conditions and a higher grade. Most of the sub-watershed areas with lower scores are urban and agricultural while most of the areas with higher scores had more natural cover. About half of the water quality stations had high levels of chloride. Ongoing efforts to improve stormwater management through low impact development (LID) practices will help to improve water quality. 

Furthermore, water quality data from the last 50 years has shown that levels of chloride, which comes from road salt, continue to increase within the watershed. In some watersheds, the values are more than double the limit considered safe for aquatic species. Currently, there is no known way to remove chloride from our environment, so prevention is key. Reducing salt application and implementing nature-based solutions, like streamside plantings, can help reduce the impacts of chloride on water quality. 


More Information

Pollution of our Streams

  • Chemical and physical pollution, including the warming of waterways, has significant impacts on water quality, and the species, including humans, that rely on clean water.
  • Pollution comes from various sources across urban, residential, and agricultural landscapes and results from choices we make, such as whether to apply fertilizers to our home garden.
  • During rain or snowmelt, pollutants and soils run off fields, roads, and yards and enter streams or are absorbed into the groundwater.

What can we do to reduce pollution in our streams?

  • Conserve natural landscapes, especially wetlands and streamside vegetation, that naturally aid in removing pollutants.
  • Reduce nutrients from entering waterways by implementing best management practices on your property.
  • Prevent stormwater from entering streams by using low impact development and redirecting water to lawns and gardens.
  • Get out and explore Conservation Halton Parks and the natural areas around you. Appreciating and exploring nature is the first step in making wise choices to help protect it.

What can your community do?

  • Support initiatives to improve stormwater management
  • Adopt low impact development practices to help reduce runoff
  • Direct development away from areas of environmental significance
  • Minimize salt use and explore new alternatives
  • Protect and connect wetlands and other natural heritage features
  • Support monitoring and restoration initiatives to improve conditions

What can agencies do?

  • Evaluate the effectiveness of their environmental programs and take steps to green their operations
  • Work together to manage natural systems to protect and enhance connected natural habitats on the landscape
  • Protect and create more urban greenspace to reduce stormwater, cool temperatures and provide healthy outdoor living and recreational opportunities for people

Over the past five years, Conservation Halton has completed many restoration projects on both private and public property, including Flamborough Centre Park, Courtcliffe Park, Drumquin Park, Area 8 and Glenorchy Conservation Area, to support watershed function and resilience to climate change.

Since 2018, Conservation Halton worked with hundreds of landowners and partners to:

  • Manage 261,600 acres of Conservation Halton lands
  • Serve over 664,000 residents in the watershed
  • Rehabilitate 231 hectares of floodplain, forest, and wetland
  • Engage 167,836 watershed residents in educational programs
  • Plant more than 319,900 trees and shrubs
  • Engage more than 35,900 watershed residents in conservation activities
  • Improve 24 km of stream habitat through restoration activities
  • Monitor over 500 sites across the watershed to decision-making
  • Manage 21 invasive species, like Garlic Mustard and Giant Hogweed

  • Work with municipal and regional partners to limit road salt usage to reduce chloride concentrations in streams and groundwater
  • Work with municipal partners to monitor stormwater management facilities and complete maintenance to minimize the likelihood of these facilities becoming sources of pollutants long-term
  • Encourage the use of best management practices on agricultural lands to reduce pollutants and prevent run-off
  • Encourage planting of streamside vegetation to reduce stream temperatures, improve water quality and create natural connections between habitats on the landscape
  • Protect and create more urban greenspace to reduce stormwater, cool temperatures and provide recreational opportunities for people
  • Support monitoring and restoration initiatives to identify healthy or sensitive areas for protection and identify areas in need of restoration