Aquatic alternative

As lakes and ponds age, they are continually impacted by sedimentation and nutrient enrichment.

Eventually, sediment and nutrient overload can lead to poor water quality and increased algae and nuisance aquatic vegetation blooms.

Due to tightened regulations regarding the use of algaecides and herbicides, it is becoming increasingly important to find alternatives for aquatic vegetation treatment programs.

INTEGRATED PEST MANAGEMENT PLAN.

Integrated pest management (IPM) is a comprehensive approach to pest management that includes many non-chemical strategies before or along with the use of pesticides. The implementation of a long-term, proactive IPM plan for algae and aquatic weed management helps to reduce the quantity of chemical products used while still providing for a healthy and aesthetically pleasing water body.

There are many different potential components to an IPM plan, including prevention, mechanical and physical practices, cultural controls and biological solutions. A critical phase in the development of a comprehensive IPM plan is to evaluate which strategies will be appropriate for a specific site.

PREVENTION STRATEGIES.

Preventing sediment and nutrients from getting into the water can provide long-term benefits for water quality since excessive nutrients can cause nuisance plants to thrive.

Establishing healthy communities of shoreline aquatic vegetation or allowing natural grasses to grow around the edges of a lake or pond will provide a filter for runoff, thus minimizing the sediment and nutrients entering into the pond. In addition, the vegetation will serve to stabilize the shoreline, preventing erosion and the introduction of more sediment into the water.

A buffer of grasses surrounding a lake or pond also makes a waterbody less attractive to Canada geese because they will not walk through vegetation over their heads. Since their bodily waste is a source of nutrients to a water body, preventing the presence of geese around the pond has its own benefits. Buffers should be trimmed at least once per year and should be selectively managed throughout the growing season, removing any woody vegetation or non-native, invasive plants.

RESTORATION STRATEGIES.

For a lake or pond with severe algae issues, strategies that improve water quality can make a difference in the overall health and appearance of the water body.

A buffer of grasses surrounding a water body makes it less attractive to Canada geese, whose bodily waste can cause nuisance plants to thrive.

Nutrient mitigation is a widely used practice that directly targets and inactivates the phosphorus in the water and bottom sediments of a water body. Unique lanthanum modified clay is the most commonly used product for this purpose. Product selection and program development would be based on site-specific conditions and the general budget for the project.

Another commonly recommended IPM strategy is the installation of an aeration or circulation system. Aeration improves a water body by adding oxygen to the system. The circulating action converts phosphorus to forms that are not usable as food by algae.

PLENTY OF CHOICES.

While there are numerous IPM strategies that can be applied as part of a long-term plan, it is important to consider all of the site-specific characteristics of your lake or pond in order to develop a successful and environmentally sustainable program. By implementing a comprehensive maintenance approach that employs a variety of water quality improvement strategies, the long-term result will be a more balanced waterbody.

The author is an aquatic ecologist with SOLitude Lake Management, an environmental management firm.