Restoration of Water Bodies

Many rivers, estuaries, lakes, ponds and other water bodies across the globe are victims of urbanization and are polluted beyond their self-recovery capacity. Uncontrolled dumping of garbage, debris and sewage into water bodies leads to an influx of various pollutants including organic compounds, phosphates  and nitrates, thereby adversely impacting the water quality. These pollutants lead to eutrophication of ponds and lakes by boosting growth of algae and undesirable weeds like water hyacinth. Excessive algal growth, in turn, interferes with penetration of light and also leads to reduced dissolved oxygen levels in water bodies, thereby hampering the growth of other aquatic organisms and disruption of the balance of the aquatic ecosystem. Due to reduced dissolved oxygen, anaerobic degradation of organic matter takes place, which leads to the production of foul-smelling gases like ammonia and hydrogen sulphide, causing odour issues in the vicinity.

Effwa offers its expertise in sustainable restoration of various polluted water bodies like lakes, ponds, estuaries etc. for reversing the adverse impacts of the pollutants by bioremediation technique. Bioremediation is a treatment process in which the affected water body is restored by in-situ application of selective biocultures (yeast, fungi or bacteria) or their consortium to degrade accumulated complex organics and other hazardous substances into less toxic or non-toxic end products. Team Effwa has demonstrated its capability in the field through some of the most challenging projects including the case of restoring over 300 years old mid-water temple and complete beautification of lake and its surroundings.

Based on the extent of pollution, source of pollutants and other project-specific considerations, we follow a tailored approach to restore water bodies by a combination of the following processes:

• Diversion and treatment of sewage: To protect water bodies from deterioration due to ingress of untreated and poorly managed sewage streams, systematic diversion systems and sewage treatment plants are set up.
• Physical cleaning of the water body: It involves the removal of weeds and floating solid waste either through manual or mechanical means. In cases where it is desirable to augment the water holding capacity, mechanical desilting operation is also carried out.
• Aeration: Surface aerators, submerged aerators or a combination of both may be used to increase the dissolved oxygen in the water, which is used by microorganisms to degrade the pollutants. Aeration also aids in mixing the different thermal layers of the water body, resulting in destratification, exposing the lower-most layers to atmospheric air. The need and extent of aeration is calculated based on the water quality parameters, depth of water body, ambient temperatures, wind conditions etc.
• Application of bio-product (bio-augmentation): Concentration and frequency of dosing of the microbial cultures is decided based on the volume of the water body, water quality parameters, ambient temperatures and extent of algal growth.
• Continuous monitoring of water quality parameters: Effwa's floating monitoring stations equipped with multi-parameter analysers are employed for uninterrupted scrutiny of the water quality.
• Beautification of surrounding areas: Development and beautification of the waterfront encourages recreational activities and enhances tourism.