What is the Restoration Pilot Project?
The Netley-Libau Marsh has been deteriorating for a number of reasons, to the point it is no longer a healthy functioning marsh.
We can still save the marsh, but the time to act is NOW!
To maintain a channel between the Red River and Lake Winnipeg, the river has been regularly dredged from 1883 until 1999. But since its interruption, sediment has been building up at the mouth of the river and started diverting a significant portion of the river flow into the marsh. Today, this marsh resembles more to a shallow-water lake. Other factors that play a role in this include manipulation of water levels on Lake Winnipeg, ice-jamming, climate change, upstream drainage, and the effect of invasive species like the common carp.
The Netley Marsh now has had extreme changes areas of vegetation used by fish, wildlife, Indigenous’ cultural traditions, recreation. It also reduces the marsh’s capacity to absorb nutrients off the water. Altered water levels are maintaining periods of high water, with short low water levels period needed for plants to sprout and grow in new areas.
The Netley Cut
The Netley Cut was originally created in 1913 to drain hayland within the marsh and to provide easier access to the marsh to harvest the hayland. Recent studies have shown that up to 50% of the flow of the Red River can move through the main channel to Lake Winnipeg. The Netley Cut has grown wider over recent decades and is one of the major causes of sustained high-water levels in the marsh.
After 1999, residents living near the Red River noticed changes in the water levels and an increased occurrence of ice jams. They believe that the lack of dredging could be contributing to flooding in Selkirk, St. Andrews, St. Clements and Netley-Libau Marsh areas as well as an increase in ice jams at the lower portion of the Red River. In response to increased ice jams, an ice breaking program was implemented with the expectation that it would alleviate flooding due to ice jams along the Red River, but it may have in turn, contributed to the increase in the width of the Netley Cut.
The widening of the Netley Cut increases the water flow moving into the Netley Marsh in spring by forcing the ice jams and moving water into the marsh through the cut.
The Restoration Project
Numerous studies suggest that resuming dredging could improve the water flow on the Red River and reduce the water moving into the marsh via the Netley Cut. In addition to this, the dredged material can be used to create sediment islands within the marsh. This form of sediment management would create a suitable habitat for the growth of vegetation and could help restore the Netley-Libau Marsh.
A group of organizations took these concerns and are now working on a pilot project the feasibility of this concept and to explore the benefits that marsh restoration could have on hydrology, sediment, fisheries, and wildlife. The pilot project plans to dredge on specific areas of the Red River and use the material could to construct sediment “shelves” within Hardman Lake.
These organizations formed a steering committee to oversee and provide governance to the projet. The committee is currently proposing to use the Amphibex ice-breaking machines currently operated by the North Red Community Water Maintenance Inc. to perform precision dredging where required. These machines are originally designed as suction dredgers and can move dredged materials up to several kilometers (with addition of booster pumps). These sediment shelves created with the dredged material will provide the locations with lower water levels that plants require for growing.
We already mentioned that a healthy marsh can improve water quality: it could remove harmful phosphorus, nitrogen, and other sediments present in dangerous quantities. Studies have also shown that a healthy Netley-Libau Marsh could have the potential to remove up to 6% of the phosphorus from the Red River before it enters Lake Winnipeg each year. This exceeds the amount of phosphorus that the city of Winnipeg, Selkirk, and Brandon combined contribute to Lake Winnipeg on an annual basis.
But this is not a novel project. A similar concept has been used successfully for marsh restoration by Ducks Unlimited in Louisiana and other parts of the world. If it worked in other parts of the world, it can work to save the Netley-Libau Marsh
Many Manitoban families have enjoyed and benefited from the Netley-Libau marsh in the past. It is our duty to preserve it for future generations, but also for the multiple benefits that a thriving marsh can contribute to the health of Lake Winnipeg and our shared waters.
A Successful Project of
Marsh Restoration at the
Paul J Rainey Wildlife Sanctuary
The Amphibex 400
The Amphibex 400 has been used for the provincial ice breaking program, it was originally meant to be a dredger.
Amphibex is a Canadian company located in Quebec. These versatile dredgers are also friendly to the environment: they are equipped with a residential silencer that reduces noise emissions and disturbances. Their hydraulic system also uses biodegradable vegetable oil that is safe for the environment
These machines have been used in Manitoba mainly for the ice breaking program.