Using heavy machinery to excavate the pond or shape the embankment dam goes relatively quickly, but it requires plenty of care and attention. Keeping the slopes around the pond as low in pitch as possible prevents erosion, increases safety when accessing and working around the water, and speeds up vegetation. Aim for a 3:1 slope or less (three inches of rise over a foot of length) for safety when using heavy equipment for maintenance around the finished pond.
Following proper building techniques for dams and levees is necessary to ensure these structures can actually hold back water. Start by removing any vegetation for good bonding between the existing and new soil. Collect topsoil, especially clay-heavy layers, during excavation and grading. Cut a core trench down the length of the dam, starting at four feet in depth and going down until you reach a solid clay layer. Pack high-clay soil into this trench, and then begin building upward for the dam or levee shape in six-inch layers with compaction between them. Install drains and spillway outlets as you layer in the material. Make sure to taper the dam so it’s less than half as wide at the top as the bottom. Finally, cover the last compacted layer with low-clay topsoil to prepare it for vegetation.
