The Nottawasaga Valley Conservation Authority

Pretty River Dike ​maintenance scheduled to start this Fall

Media Release

For Immediate Release​

UTOPIA, Ontario (September 22, 2021) – The Nottawasaga Valley Conservation Authority (NVCA) and the Town of Collingwood will begin maintenance activities along the Pretty River Dike this fall.

The Town of Collingwood was built on a shallow flood plain, making the urban areas prone to flooding. Some of the most notable floods are the 1912 Victoria Day Flood and the 1942 St. Patrick’s Day Flood. The Pretty River Dike was built in the 1970s to reduce the risk of flooding in the urban areas of Collingwood.

Map of Pretty River Flood Plain

The dike was designed to contain flood waters from the Provincial Regulatory Storm Event. Floods have become more problematic within the last decade across Ontario. According to the Ontario Special Reports on Flooding, areas across the province has been experiencing record-setting floods. This issue has been acknowledged by the Insurance Bureau of Canada that floods are one of the most expensive and catastrophic natural hazards. Although these events are rare, the risk to property damage and possible loss of life is high, which is why the di​ke must be maintained.

The dike is covered in 12″ to 18″ stone which protects the bank from the erosive forces of flowing water. Currently, dense groundcover, trees and shrubs can slow down the flow of flood waters and reduce the capacity of the channel. This could lead to flood waters spilling over and causing property damage and threat to public safety. NVCA removed vegetation on the dike from 2006 – 2007, however the maintenance was not continued due to lack of funding.

River Trail, the recreational trail on the top of the dike will continue to be available to residents and visitors. Both NVCA and the Town understand that the vegetation and tree canopy is part of what makes River Trail special. However, the channel must be maintained to protect residents and properties including homes and businesses, the Collingwood Public Library, Collingwood Museum and Central Park.

To strike a balance between community safety, water quality and habitat protection, groundcover such as grasses and wildflowers will not be removed. These plants are important habitats for pollinators, including Monarch butterflies, a species of concern. Groundcover is also a great foraging source for many birds. Low shrubs such as dogwood and willows along the edge of the water will not be removed to continue to support fish and wildlife habitat.

Maintenance activities will be completed in two phases. Phase One includes removing the small trees and large shrubs along the slope of the dike. This will allow Phase Two, which includes assessing larger trees and shrubs and developing a plan to remove those that are compromising the capacity of the channel to convey floodwaters. Trees above the slopes will not be impacted other than to provide access where absolutely necessary. More information about Phase Two will be available after Phase One is complete.

The work will begin on Sections 4 and 5 of the dike. Phase One will start in the Fall of 2021, and Phase Two is expected to start in 2022. To protect nesting migratory birds, vegetation removal will not take place between April through July. Maintenance work will be ongoing, and the trail will remain open for use but residents should expect trail closures for safety.

NVCA will be hosting an online Q&A session on Wednesday, September 29 from 5:30 p.m. to 7:30 p.m. to answer any questions or concerns residents have regarding the Pretty River Dike or maintenance activities. Please visit NVCA’s websiteFacebook or Twitter for more details.

Residents can learn more about the maintenance project by visiting Engage Collingwood.

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About NVCA: The Nottawasaga Valley Conservation Authority is a public agency dedicated to the preservation of a healthy environment through specialized programs to protect, conserve and enhance our water, wetlands, forests and lands.

Media contact: Maria Leung, Communications Coordinator 705-424-1479 ext.254,

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