Whiteshell Provincial Park Shoreline Restoration

Shoreline Stabilization Project Using Bioengineering

Caddy Lake, Whiteshell Provincial Park, Manitoba, Canada, 2007.

Problem: Water levels on lakes with in the Whiteshell provincial park have become increasingly subject to extreme water level fluctuations. This has been aggravated over the past 20 years by logging activities on the park perimeters, as well as increased development which has continually changed water sheds. Caddy lake is the first in a chain of lakes which is fed by many small marsh lands, creeks, rivers and lakes, as well as the major water body of West Hawk Lake.  Inflow to the small lake is of a large magnitude, however outflow is extremely limited.  Caddy Lake outflows through a man made rock tunnel (culvert) at its North End.  The limited release of water leads to drastic water changes in short periods of time.  With the increased occurrence and amplitude of these floods, shoreline erosion had become prevalent on the small lake.

Project Background: The project location has been under the same family’s ownership for the past 42 years.  Over the years many attempts to arrest the shoreline erosion have been made, which have included rip rap placement, soil filling and seeding, and most recently bioengineering.

With the permission of the property owner, Mid-Canada Hydroseeding began the installation of an Enviro-Lok shoreline stabilization system.

Solution: The existing shoreline was levelled to a 3:1 slope with limited addition of native slope fill provided by the property owner.  Existing site rip rap which had mostly fallen into the lake was recovered and placed at the bottom of the system to create a system toe, which would act to offer wave dissipation and system anchoring.  The system was then constructed by placing geotextile material over the existing compacted site soil.  The Enviro-lok bags were then placed and compacted into place.  The bags were pinned together, and secured with a geogrid matrix.  Native plugs were placed between the bags, and when completed the bags were seeded with a boreal shoreline native seed mixture of grasses and flowers.  The yard above the system was restored with topsoil and straw erosion control blanket and turf seed mix, to provide a maintainable yard area for the owner.

Project Review: The owner is very pleased with the results and look after the first growing season.  Four trees that were almost lost due to shoreline erosion have been saved and the customer has noticed a dramatic change in the overall health and foliage of the trees.  The native plugs have rooted and are performing very well, and the native seed mixture has undergone substantial growth in the short period from mid-summer.  We will be continuing monitoring of this site, and the erosion protection will only become stronger with time.