Most of the natural and artificial lakes/ ponds / lagoons have a defined purpose for being in existence, A Lake is a water retention facility. It can store water (for flood control), give good aesthetics and provide water for many purposes such as water supply, irrigation, fisheries, tourism, etc. In addition, it serves as a sink for carbon storage and provides important habitats for numerous species of plants and animals.
Most of the time the lakes become an insalubrious, due to pollution, gets flooded due to low water retention capacity, cause foul smell, becomes a safe haven for the mosquitoes, turns green due to algal boom and becomes unsuitable for fishes and other aquatic creatures and most importantly the water quality in the lake deteriorate and becomes unsuitable for irrigation and other defined use. Simply because it’s not been maintained. Hence restoring lakes consists of a detailed study of the entire water shed to enhance the structure and functioning where they have been drained in former times.
Most lake pollution problems are caused by nutrients, contaminants, and sediments carried into the lakes. In a typical watershed, nutrients may come from sewage, wastewater, agricultural and urban run off, and atmospheric fallout. Heavy use of TSE water, fertilizers and pesticides have increased the severity of the problem.
High concentrations of nitrogen and phosphorus are the main causes of algal growth, which results in the deterioration of the lake water quality. Algae affect the quality and appearance of water. They cause taste and odour problems in municipal water supplies and excrete toxins into waters. Blooms of algae adversely affect recreational activities like swimming, boating and fishing. High algal growth leads to large masses of dead plants which settle to the bottom and cause dissolved oxygen deficiencies on decomposition. Fish die along with algae, and anaerobic decomposition releases ammonia, causing more fish kills.
The lake / pond restoration works includes detailed study of the entire water shed and preparation of lake / pond management plan which includes both short-term and long-term strategies.
The overall lake restoration plan is comprehensive and covers all aspects related to the water quality management and satisfy the different uses (re creative, aesthetic, agriculture, ecosystems, irrigation...) .
Protection against floods could be improved by a better management of water levels and rehabilitation of banks. Water quality monitoring is the most important tool to provide confidence in the effectiveness of the measures considered in the lake restoration process.