“LiDAR, which stands for Light Detection and Ranging, uses lasers that are completely invisible and safe for your eyes,” said Brent Bass, geospatial services division manager at DRMP. “It sends a laser to the ground or a building, then records how long it takes for the signal to bounce back.”

This scanning process happens rapidly — at a rate of 3.6 million measurements per second, according to Bass. The data collected from a LiDAR survey forms what is known as a point cloud.

“A point cloud is made up of thousands or even millions of points, each with x, y and z coordinates that show the precise location of objects and surfaces,” Bass said. “When we put all these points together, they create a detailed 3D map of the land.”

The resulting point clouds — such as those generated in the Historic East Winter Garden survey — can be enhanced visually by applying a color scheme. This technique functions like a digital filter, enabling viewers to interpret terrain changes more easily.

“Point clouds are originally black and white, but we can apply different color schemes to see what is going on,” Bass said. “For example, I can set it to show elevation, so lower areas might appear blue, and as elevation increases, the colors shift toward red, following the rainbow spectrum.”

Monahan shared the survey’s findings with VoxPopuli, noting the LiDAR survey revealed the yards in the area sit at a lower elevation than the surrounding streets — an observation that helped the city communicate the flooding risk to Orange County.

DRMP conducted the survey using an aerial drone to scan the area from above, while also using a mobile vehicle with special LiDAR equipment that scanned the streets in both directions, providing a “complete point cloud covering the entire project site.”

“We then gave the point cloud to [geospatial software company] TopoDOT, and they used it to create different types of models, such as drainage and elevation models,” Bass said. “This helped us quickly identify which yards in the neighborhood were higher or lower, so we could see how water would drain across the area.”

The $6.5 million federal grant will pay for the design and construction of a new drainage system to fix the problems the initial study identified, particularly the standing water — known as “yard pooling” —  that collects in residential yards after heavy rains and storms along five neighborhood streets. The end goal of the Bethune, Edgeway, Basin, Maxey & Dunbar Drainage Project is to divert stormwater out of the area and reduce flooding.

“When the county had this area under their jurisdiction, they supposedly came in and paved, put drainage in. But when they did that, they built the streets up a little bit higher than some of the existing homes,” Monahan said. “Even though the water is collected, some of the areas, the lowest areas, are actually people's yards.”

Residents in the area attempted to solve the problem themselves, building makeshift pumps to move floodwater from their yards into nearby storm drainage systems. The issue came to the city’s attention when residents living on Maxey Avenue called Monahan personally.

“These folks panic when it rains, and I don't blame them,” Monahan said. “It's your home, and it probably has been in the family for decades. Multi-generational homes are continuously getting water underneath. It’s got to be stressful.”

After receiving the block grant approval, Winter Garden was required to request approval from the Orange County Board of County Commissioners, which it received as part of the Infrastructure and Public Facilities Program, according to a June 4 document. 

Each phase of the drainage project is detailed in the city’s CDBG-DR presentation to Orange County, which served as the basis for its funding request. Step one involved DRMP conducting the LiDAR-based survey of the area and Winter Garden-based TopoDOT organizing the resulting data to show low-level yard elevations.

Step two involves the city conducting conventional topographic data collection. The study will reveal what lies beneath the surface, unlike the LiDAR survey, which provided only a broad view of surface elevation. This phase will uncover the precise heights and positions of homes, utility lines and tree root systems.

Once topographic data is collected, the city will hire a civil engineer to design a stormwater collection system. This may include additional storage areas — either natural or engineered — designed to temporarily hold excess stormwater during heavy rain events to prevent flooding. 

Step four involves hiring a contractor to construct the stormwater management system, based on the engineering plans developed in the previous phase. This work involves building new drainage systems and adding more space to hold stormwater, if needed, to help prevent flooding in the lower-lying homes found in the initial LiDAR survey.

It’s estimated the project will take three years to complete, Monahan said.