What are the best practices for sustainable management of lakes and ponds, especially those in urban areas?

Water bodies in many urban areas are highly polluted with waste. Many of them are encroached by construction and real estate. Many more are poorly managed. Monitoring and maintaining these water bodies are critical to sustainability, especially for urban areas, because these lakes and ponds are essential for sustainable water supply for the neighborhood. What could be effective and sustainable ways to manage our lakes and ponds?