Flocculants cause all of the fine suspended material in your dirty water to fall to the bottom of the first pond immediately. This settling will generally happen within 30 feet of the discharge pipe going to the pond. Only clean water will typically leave the first pond; hence you can shut down any additional ponds, reducing your overall water treatment footprint.
The solids are also far more concentrated and compacted and, therefore, easier to move. When you clean the pond with a backhoe, you will get a larger bucket of material with each scoop, and the mud will dry out more quickly than un-flocculated mud.