This budget also assumes that an adequate supply of suitable quality water can be obtained from a shallow well. The six 2-acre ponds are built in a block with each pond having a water surface of 165 feet by 528 feet. The central levee is 16 feet wide and all other levees are 12 feet wide. Internal slopes are 4:1 (4 horizontal feet to each vertical foot) and external levees have 3:1 slopes. Freeboard (height of levee above the waterline) is 1 foot; 10 percent is added to total yardage to allow for compaction over time. Tractordrawn pans should be used in construction rather than bulldozers, and proper construction procedures are critical. Poorly built ponds are impossible to repair well and usually very difficult to manage.