Herbicide Application

Algae Blooms

Most algae in District canals is not harmful to human health and provides a food source for aquatic life 

Algae are simple organisms that grow through photosynthesis, a process by which sunlight is used to metabolize nutrients. Algae are a basic component of the food chain and can be found in marine, estuarine, fresh water lakes, canal systems and even swimming pools. Algae appear as green, red or yellowish-brown particles that float on the water surface.

Most algae found in District’s canals, while visually unappealing, are not harmful to human health. However, some types, like “Blue-green” algae, which is a cyanobacteria, secrete toxins that may be harmful. The algae toxins can be inhaled by people living around the waterbody. It will aggravate respiratory illnesses like asthma. Symptoms of exposure to toxic algae include difficulty breathing, wheezing, skin rashes, headaches, and possibly tingling in the fingers and toes if the water was consumed.

Although algae are a normal component of an aquatic ecosystem, nutrient-rich waters warmed by the summer sun, provide a favorable medium for the overgrowth. This overgrowth is called an ‘algae bloom’. Herbicide or chemical treatments for the removal of algae uses a heavy metal compound that may adversely impact the waterbody. Since algae is a food source for aquatic animals and does not impact flood control operations, the District does not regularly treat its canal system for algae blooms. Most algae growth in our canals is harmless and will dissipate on its own or will be flushed out after a heavy rainfall.

Additional information on algae toxins can be found at the US Environmental Protection Agency and the Center for Disease Control website at www.epa.gov/nutrientpollution/harmful-algal-blooms.

Aquatic Crew in boat

Controlling Aquatic Plants

Two different methods are used for more efficient control of aquatic vegetation growth 
Lake Worth Drainage District regularly treats and removes aquatic vegetation in canals to maintain the flow of water and facilitate effective flood control for communities in Southeastern Palm Beach County. To accomplish this task, the District utilizes both mechanical and herbicide treatment to remove unwanted vegetation.

Containment Boom

Recently, the District has expanded its mechanical removal of aquatic growth with the use of containment booms. Containment booms are floating ribbon-like structures that span the canal cross-section and extend approximately one foot both above and below the water surface. As water flows through a canal or as winds move across the water’s surface, floating debris will move through the canal network. The booms serve as a physical barrier, “corralling” the debris while allowing water to continue to flow unimpeded. Installed at critical locations in order to concentrate floating vegetation and other debris, the booms allow District staff to more effectively collect, treat and dispose of the material.

Herbicide Application

Given the proliferation of aquatic vegetation in Florida’s subtropical climate, it remains necessary to continue the use herbicide treatment to control vegetation growth. When applying herbicides, the District strictly adheres to the rules and regulations established by the U.S. Environmental Protection Agency (EPA) and the Florida Department of Environmental Protection (FDEP). Staff applying chemical treatments are trained and certified annually on the proper application and handling of all herbicides used. Periodically, the District receives calls from residents regarding an odor detected after the application of herbicides. Although this concern by residents is understandable, it is important to know that the odor is an expected occurrence the oil emulsion that is mixed with the herbicide. Emulsion herbicides are a thicker consistency, allowing the herbicide to adhere to the vegetation so that it stays in place long enough to be effective.

With more than 500 miles of canals, the District is continually conducting maintenance of its canal system. Effective flood control and your safety is dependent on well-maintained canals.
fish in pond

Dead Fish in Ponds, Lakes and Canals

Most fish kills are the result of natural processes

When a fish kill occurs in a lake, pond or canal, the first assumption is  that something is terribly wrong with the water body. Suspicions are raised as to whether human activity, such as a chemical spill, may have caused the fish to die. However, most often fish kills are the result of natural processes that cause the oxygen dissolved in the water to drop to levels insufficient for fish survival. A dissolved oxygen, or DO-related fish kill can occur in virtually any aquatic environment, but water bodies located in residential areas are particularly vulnerable. Developed areas create rainfall runoff that may contain high amounts of nutrients from septic tanks and fertilizers. Water bodies with high nutrient levels can produce a dense growth of algae. When sunlight is available, the algae use the nutrients in the water to produce oxygen through the process of photosynthesis. Most of the oxygen available to fish comes from this process. However, nighttime and cloudy or low sunlight days causes the algae to switch from photosynthesis to respiration, which results in the algae consuming the oxygen needed by the fish population. Clean-up of fish kills occurring in private residential ponds and lakes is generally the responsibility of the property owner or homeowners association. Fish kills in District canals should be reported by calling 561-498-5363 or emailing info@lwdd.net.
Community pond weir

Plan Ahead for Aging Infrastructure

Author: Bob Foster, President of Citrus Glen

In August 2012, during the middle of Tropical Storm Isaac, I found myself watching the floodwater rise in my community. With the authorization of the Lake Worth Drainage District (LWDD), I opened Citrus Glen’s discharge control structure. This was a challenge as the lake had risen above the dock and weir mechanism.

Several hours later, when the flooding did not recede, I inspected the end of the pipe that discharged into the canal and realized the pipe was bent and restricting the flow of water. After discussing the pipe with LWDD, they agreed to help repair the pipe but they felt it was not the sole cause of the community’s flooding. District personnel asked how long it had been since the community had its drainage infrastructure cleaned and inspected. It was at this point that I learned Citrus Glen’s pipes, inlets, lakes, and swales, belonged to the community and I had a lot more to learn about the community’s role in flood control.

Over the course of the following year, I was fortunate to locate the original underground pipe design. Citrus Glen had just over one mile of underground pipes, but no one knew what condition they were in. The community hired a contractor to inspect and clean the drainage system for the first time in 25 years. A video inspection illustrated areas where tree roots had infiltrated the pipes. If these pipes failed, potential catastrophic damage could occur!

For a second opinion, the community hired an engineer to review the video. He determined that approximately 50% of the pipes needed immediate attention. Our solution was to install CIPP sleeves (CIPP – Cured in Place Piping). This was the least expensive and most favorable option since the CIPP product could be installed without having to trench around homes or dig-up sidewalks and roads in order to replace the failing pipes.

The work was completed in 2015 at a cost of $905,000. This was an expense our Board had not planned for, but Citrus Glen now has a drainage system that is projected to last 50 plus years. In addition to repairs to the pipes, we raised the structure two feet and installed a new aluminum dock with handrails for safer access.

I share this story because aging drainage infrastructure is a problem that many communities are unaware of nor are they planning for such repairs in their budgets. I encourage communities to learn about their drainage system and begin reserving funds for this critical infrastructure. It is not a matter of “if” but “when” you will have to upgrade.
 
For questions, contact:
Bob Foster, Citrus Glen Board President