A lot of the urban area consists of large planned communities, often for retirees. Many of these communities incorporate artificial residential lakes. Digging out these lakes provided construction fill for roads and elevated low-lying land for development. The lakes also reduce the risk of urban flooding by capturing storm water runoff, and add aesthetic value.
Comparing the images in this time series, the number of small water bodies increases substantially. The small dark shapes are scattered throughout the green shades that indicate residential areas, along with golf courses, which appear brighter green. The dark green in the lower left is the Loxahatchee National Wildlife Refuge.
An image from Sentinel-2 at 20-meter resolution shows even more clearly these residential lakes, golf courses, and suburban areas.