Water hyacinth spreads mainly by growing new plants from existing ones, creating dense clusters. It can also spread through seeds, though this is less common. First introduced into the lake through the Kagera River, the plant has become a serious problem. In 1996, satellite images showed that water hyacinth covered about 1% of the lake, and now it is estimated to cover as much as 3%.

Aquarius Systems, a company specializing in water management, has been selected for a project to remove the water hyacinth from Lake Victoria. Under the Lake Victoria Environmental Management Project (LVEMP), the company will cut and remove 1,500 hectares of the invasive plant over 12 months. This effort is funded by the Global Environmental Facility and the International Bank for Reconstruction & Development.

To tackle the problem, Aquarius Systems will use special equipment, including two “Swamp Devils” and one aquatic plant harvester. The Swamp Devil is a powerful machine that can cut through thick vegetation, including small trees. The harvester will collect and remove the cut plants. This method is a more environmentally friendly alternative to using herbicides, which could harm the lake’s ecosystem.

Managing Lake Victoria’s water quality is a long-term effort. The removal of water hyacinth is an important step, but more work is needed to fully restore the lake’s health. One possible solution is to turn the removed plants into compost for fertilizer. This approach could provide additional benefits to local farmers while helping to control the spread of water hyacinth.

This project is an example of how mechanical solutions can help manage environmental problems without harming nature. While there is no quick fix for Lake Victoria’s issues, this effort is a step in the right direction. People around the world are watching to see how this project unfolds, and it could serve as a model for future lake restoration efforts.

For more information on this project, visit Water-Hyacinth.com Please note that the website is currently live but will be undergoing redesign soon. the right direction. People around the world are watching to see how this project unfolds, and it could serve as a model for future lake restoration efforts.

Mechanical Harvesting – A mechanical aquatic harvester (harvester) is a type of barge used for a variety of tasks, including aquatic plant management and trash removal in rivers, lakes, bays, and harbors. Harvesters are designed to collect and unload vegetation and debris using a conveyor system on a boom, adjustable to the appropriate cutting height, up to 6 feet below the surface of the water.

Shredding – Swamp Devils and Cookie cutters are small barges designed to shred aquatic weeds, equipped with engine-powered, front-mounted blades. The cookie cutter was developed to address emergent aquatic vegetation and floating islands of vegetation and sediment, and to cut openings in shoreline and wetland areas through emergent wetland plants (USACE).

Mechanical Control Methods – USACE

The U.S. Commercial Service recently presented an Export Achievement Award to one of its longtime clients, Aquarius Systems of North Prairie, Wisconsin. The company was lauded for its contributions to water purification in Malawi and for expanding into the South Sudan. Using the Aquarius Systems’ Swamp Devil Aquatic Vegetation Shredder as boats traveled through swamps to deliver food, the UN was able to provide sustenance to more remote African locations after devastating floods.

Shown here with the award (right to left) are Diane Farrell, Deputy Under Secretary for International Trade; Jane Dauffenbach, President/Owner, Aquarius Systems, U.S. Commercial Service Milwaukee Director Koreen Grube, and International Trade Specialist Shari Stout.

Innovative Technologies for Lake Management

Africas’ Lake Victoria is the second largest freshwater lake in the world. It is less than 260 feet at its deepest point. For nearly ten years a growing water hyacinth infestation has wreaked havoc on the neighboring countries. Massive islands have formed that blow around from one region of the lake to another, like big green icebergs. When one of these masses settles into a port or bay, it paralyzes local fishing and transportation.

The Solution

Aquarius Systems proposed using three Swamp Devil Aquatic Vegetation Shredders to perform the work.  The Swamp Devil is a powerful machine fitted with two circular cutting blades on the bow that also serve to propel and steer the vessel.  By using a special double blade system, the machine could shred the water hyacinth into small pieces.

Read: Managing Aquatic Plants on a Massive Scale

The Swamp Devil Aquatic Vegetation Cutter (formerly known as the Cookie Cutter) has been used on Lake Victoria since 1998 to help control dense mats of water hyacinth. A film crew from National Geographic visited our base in Kisumu for three days to shoot exciting footage of the equipment in action. While they were out on the lake, they happened to film a rescue made by the Aquarius staff, who retrieved two fishermen who had been trapped in their boat for two days, stuck in the dense weed growth.

The exotic water hyacinth has severely impacted the Lake Victoria region from both an environmental and an economic perspective.

Watch the Program

Botanically, wild rice differs from common rice, and is actually a cereal grass that grows in shallow lakes and streams, ripening in late summer. While the range of wild rice stretches from Manitoba to Florida, the most prolific stands are located in the upper Great Lakes of Michigan, Wisconsin, and Minnesota. Today Wisconsin has seventy major rice fields in thirteen counties. The grain usually begins to ripen in sections of the Wolf and Wisconsin rivers before lakeside areas are ready to be harvested.

Only Wisconsin residents may harvest wild rice in the state and must purchase and possess a wild rice harvesting license.   Harvesters are limited to gathering wild rice in boats no longer than seventeen feet and no wider than 38 inches that must be propelled by muscular power using paddles or push poles. The grain is still harvested by hand using wooden sticks (flails) that bend the tall stalks over the canoe. As the seed heads are tapped, some rice falls in the canoe and some in the water to seed the bed for future years. The flails must be rounded wooden rods or sticks no more than 38 inches long and hand-operated. Harvesting should be done gently, so that the stalks and beds can be harvested again as more rice matures.

Many of the large wild rice beds in Wisconsin have been lost due to pollution, exotic species, large boat wakes and especially changes in water levels.  Dams erected many miles away can also affect the harvest, for wild rice grows in the shallow parts of lakes and streams, maturing best if a fairly constant water level is maintained. The primary method of wild rice lake management is by controlling water levels on the lakes by operating water control structures (dams), ditch maintenance, and beaver dam management.  Aquarius Systems’ equipment is also used to help maintain the wild rice by removing aquatic vegetation and helping to restore the flow of water.

An aquatic vegetation cutter (AVC) better known as a Swamp Devil® effortlessly plow through bogs, water hyacinth, cattails, small trees, tulle, tussocks and other stubborn growth.  In the process it also carves through the subsoil creating an open water channel up to three feet deep and eight feet wide, allowing the water to once again flow freely.

Learn More about Wisconsin Wild Rice