Freshwater Rivers are essential to the urban environment and help people in many ways, both directly and indirectly. Insects are a common and very diverse group in aquatic systems. They serve as model organisms to analyze the structure and dynamics of freshwater ecosystems and as a source of food for vertebrates and invertebrates of much aquatic systems.The presence of insects in aquatic environments can reveal various environmental variables within the water. An interesting class of creatures, insects are involved in decomposition, energy transfer, cycling of nutrition and interaction of prey-predator. Insects are important because of their diversity, ecological importance, and impact on agriculture, human health, and natural resources. These contain about 58% of the world's known biodiversity. They are essential for the stability and functioning of both terrestrial and aquatic ecosystems. Insects play an important role in our daily lives and have a variety of impacts on human well-being. Along with this, many unknown species are also disappearing from their original habitats across the world as a result of human interference. Aquatic insect reproduction is greatly affected by heavy metals, which reduce biodiversity and reproductive success. According to research, exposure to metals like cadmium, copper and zinc can disrupt the reproductive process of many aquatic species. Despite the fact that heavy metals pose a major threat to the reproduction of aquatic insects, some research suggest that certain species may be resilient, pointing to there is a need for further exploration into adaption processes.