Ponds need to be kept clean and healthy for enhanced animal life and the surrounding environment.
Considering that ponds are small bodies of standing water, (and do not receive any freshwater) it is understood that they can easily become unhealthy ecosystems. Sediment, silt, and other items, such as trash, can fill up the bottom of a pond. This material build-up can then limit the quantity of water and oxygen for plant life and fish.
The solution: Dredging. Dredging is the best process to keep your pond clean and stop excessive weed growth.