Graphic of 4 ponds with FTWs with varying percent coverage and placement (random or strategic). Pond 1: 9% random, Pond 2: 18% random, Pond 3: 3.5% strategic, Pond 4: 1% strategic.

Figure 5. FTW designs in four North Carolina wet pond retrofit studies. The checkered blue shapes indicate approximate FTW positioning. Pond 1 contains 12 FTWs in body of pond. Pond 2 contains 4 FTWs in body of pond. Pond 3 contains FTWs encircling pond outlet. Pond 4 contains three linear FTWs placed perpendicularly just upstream of outlet.