rose colored sunglasses

Required Degree of Canal Maintenance

/in , ,

The Lake Worth Drainage District’s (LWDD) stormwater management system is made up of the canal channels, rights-of-way on each side of the canals, and controls structures and pumps. Consisting of a network of more than 500 miles of canals, over 1,000 miles of rights-of-way, and 20 major control structures, LWDD provides effective flood control and water supply for residents, businesses, and agriculture within its boundary.

Effective stormwater management is dependent on well-maintained canals and rights-of-way. But what defines ‘well-maintained’? A canal or right-of-way that some property owners may consider an eyesore is often considered well-maintained for flood control operations by water managers.

Some of the necessary components for effective flood control include the free flow of water in the canal channels to divert excess stormwater from properties, and unencumbered canal rights-of-way to provide access for regular maintenance and emergency response. Through the process of aquatic vegetation control, canal bank mowing, and encroachment removal, effective flood control maintenance is achieved.

There are numerous species of aquatic plants found within the LWDD’s canal system. Some aquatic vegetation has the potential to slow the flow of water within the canal channel or control structures. This vegetation growth is controlled with the application of herbicides and/or mechanical removal. Although not esthetically pleasing to some property owners, algae in canals is not a threat to flood control. Because algae are very small plants that break apart easily, they can pass through drainage pipes and control structures. This is good news since the herbicide used to treat algae can be harmful to the water body.

Canal rights-of-way and banks are mowed approximately 3 to 4 times a year. Flat-mowers mow the rights-of-way, and arm-mowers maintain the side slopes of the canals. High grass does not prevent access to canals or threaten flood control operations. It is not uncommon for grasses to grow several inches in height before mowing crews return to an area.

To enhance their property, residents adjacent to a canal sometimes place unauthorized vegetation or structures such as swing-sets, fences, and sheds on LWDD’s right-of-way. Encroachments must be removed because they may fall into the canal during high wind events causing blockages or slowing the progression of drainage. Additionally, encroachments can obscure sightlines for visual inspections, and impede LWDD’s access which is a critical component for public safety.

Flood control and the maintenance it requires comes at a cost. All property owners within LWDD’s boundary, whether adjacent to a canal or miles inland, are assessed at the same tax rate. In 2021 the assessed rate is $49.50 for a parcel equal to or less than an acre in size. By operating its stormwater management system to well-maintained flood control standards, LWDD can achieve its mission of effective flood control at a fair and affordable cost for all its residents.

Trash Dump on canal

Canals Are Not Dump Sites

/in , ,

Discarding of vegetative debris or other trash in the Lake Worth Drainage District (LWDD) canals or along the rights-of-way is illegal. Under the “Florida Litter Law” (Link: Florida Statute 403.413), dumping materials on public or private property is punishable by fine and potential jail time. Within LWDD’s service area, illegally dumped items are largely non-hazardous solid wastes that are inconvenient or costly to dispose of properly. Typical litter items include household trash, furniture, appliances, tires and vegetative debris from lawn maintenance and tree trimming.  Offenders most often include residents, construction, and landscape contractors.

Some of the negative effects of illegal dumping can impact public safety, the surrounding environment, and the local economy. For example, using a drainage canal as a dump site can reduce the flood control capacity of the canal and threaten the health and safety of residents. Additionally, trash dumped on the canal right-of-way can impede access needed for regular maintenance or emergency response during severe weather. While landfills are designed to prevent waste from leaching into the ground or adjacent waterbody, this is not true for illegal dumping which can harm local areas. Finally, dumping is an eyesore that negatively affects surrounding property values and governments must redirect resources to clean-up materials and provide pollution mediation.

If you witness an illegal dumping incident in progress, call your local law enforcement agency or 911. Catching dumpers in the act is the best way for police to apprehend dumpers and deter future violations. Never confront someone who is dumping. Instead, try to get the vehicle license number and description of the vehicle used to commit the crime. Most importantly, share this information with your neighbors and encourage them to always dispose of trash properly. For more information on the proper disposal of trash visit Palm Beach County Solid Waste website at ( https://www.swa.org/408/For-Residents )

Operable Control Structure

Operable & Non-Operable Structures

/in ,

In coordination with the South Florida Water Management District permit, the Lake Worth Drainage District (LWDD) allows two types of discharge control structures in residential communities and commercial properties – Operable and Non-Operable. The labels Operable and Non-Operable do not pertain to the structure’s ability to provide flood protection, but rather identify the type of structure and the way it is designed to function.

Bleed Down Orifice graphic

Figure 1. Discharge Control Structure

Non-Operable Structures, also known as ‘passive structures’, typically have an overflow weir or a triangular “bleed down” orifice installed at the stormwater pond’s designed water-control elevation. These overflow orifices allow the gravity flow of water through the structure and into drainage canals until the pond water rests at the designed water-control elevation. Given its passive nature, water will flow through the structure virtually any time there is rainfall except during very dry conditions when pond levels are lower than the water-control elevation.

So, why are there Operable Structures? A series of normal rain events can sometimes raise the level of the stormwater pond faster than the Non-Operable Structure can remove the water. The Operable Structure includes the passive flow described above, as well as a vertical slide-gate with an operating mechanism (usually a hand-wheel) that can be manually opened or closed to control the rate of water flow from the pond to drainage canals. The Operable Structure can be opened to manually lower the pond elevation after a rain event or before major weather systems like tropical storms or hurricanes.

It is important to note that the Operable Structure can only be opened with permission from LWDD. Sometimes that permission is granted at the request of an individual community or business. However, more often LWDD will give blanket permission to all communities and businesses based on forecasted weather conditions. In those situations, LWDD will provide notification by email and give a specific time to operate the Operable Structure. Communities and businesses can register designated representatives to receive these notification emails at https://lwddnet.wpengine.com/property-managers-hoa.

LWDD is the only drainage district in the State of Florida that allows Operable Structures.  It requires close coordination with local and regional authorities, but we believe it provides flood control benefits to the residents living within the LWDD boundaries.

Control Structure general

Technology & Flood Control

/in ,

Occurring anytime of the year, our tropical rain storms can be intense and seriously threaten property and life. In response, Lake Worth Drainage District (LWDD) staff monitors canal elevations daily and coordinates the operations of its water control structures. Water control structures act like dams, allowing stormwater to be released or held back depending on the conditions.  The automated technology used to operate the LWDD’s water control structures is called Supervisory Control and Data Acquisition (SCADA). As water rises in the canal and reaches a pre-determined elevation, SCADA will slowly open control structures releasing water for flood control. Similarly, as water elevations return to normal levels the control structure gates will close, holding water back for conservation and water supply demands.  In anticipation of severe weather, District staff can override the automated SCADA system and make manual adjustments.

Additionally, SCADA technology eliminates the need for LWDD staff to venture out during dangerous weather conditions to operate control structures. If needed, staff can adjust a control structure via a mobile device from any location, thus significantly reducing response time. Another advantage to SCADA, is the capture of operational data by the system which can be used to evaluate future water supply needs and historical flood control responses. This data can be shared with regional water management partners for enhanced flood control coordination and water conservation measures.

With approximately 500 miles of canals and 20 major water control structures, the Lake Worth Drainage District is one of the largest water control districts in Florida. We are proud to provide our residents with this enhanced water management technology and dependable flood control.

Man cleaning flooded home

The Probability of Flood Risk

/in ,

In some places homes and businesses constructed in areas known as the 1-in-100-year flood plain have been hit by multiple floods in the same year. The assumption that if their area has experienced a 1-in-100-year flood, then for the next 99 years they do not have to worry about flooding is not correct.  While it is unlikely that two large storms will happen in close succession, history has demonstrated that it is not impossible.

Confused by the term 1-in-100-year flood, many people begin to wonder what their flood risk really is. The definition of a 1-in-100-year flood is a flood that has a 1% chance of occurring in any given year. Understanding the probability of your flood risk can be a complex process, but the hydrologists at the U.S. Geological Survey (USGS) are striving to communicate risk more effectively, in part by transitioning away from the term 1-in-100-year flood and instead referencing multiple year flooding probabilities. For example, a home in the 1-in-100-year flood plain, can be better understood as a home with a 26% chance it will flood over the course of a 30-year mortgage.

Providing residents and community leaders with a clearer understanding of the probability of flood risk for a location is important. It allows decisions to be made that will better protect themselves and the community. For more information on flood risk probability, visit the USGS website at https://www.usgs.gov/special-topic/water-science-school/science/floods-and-recurrence-intervals.