Sasthamkotta Lake: Where Nature Meets Urban Challenge
Sasthamkotta Lake, located in the Kollam district of Kerala, is the largest freshwater lake in the state and serves as a critical source of drinking water for over 12 lakh people in the region, according to the Kerala State Water Resources department. This lake not only supports local communities but also plays a vital role in maintaining the ecological balance of the area.
Sasthamkotta’s serene waters and lush surroundings are deeply intertwined with the cultural and religious heritage of Kerala, making it a revered natural asset for the people of Kollam, as noted by Kerala Tourism.
Despite its importance, Sasthamkotta Lake has been facing increasing environmental stress over recent decades. Rapid urbanization, unchecked sewage discharge, and solid waste dumping have severely compromised its water quality and biodiversity, as highlighted in the Central Pollution Control Board Report.
The consequences of this degradation extend beyond ecological damage, affecting the health and livelihoods of surrounding communities who depend on the lake. The lake’s deteriorating condition is emblematic of the broader environmental challenges plaguing many urban and peri-urban water bodies across India, as outlined in the NITI Aayog Report on Water Quality.
The Earth5R BlueCities initiative offers an integrated and science-backed approach to waterbody restoration, combining community engagement, innovative technology, and sustainable waste management.
Drawing inspiration from successful cleanup efforts like the Mumbai River Cleanup and the Mula-Mutha River Restoration in Pune, Earth5R is well-positioned to implement a comprehensive restoration program for Sasthamkotta Lake.
The current state of Sasthamkotta Lake calls for urgent, multi-layered action involving government agencies, civil society, and corporates through Corporate Social Responsibility (CSR) programs—most importantly, with active citizen participation.
This article presents a detailed examination of the challenges facing Sasthamkotta Lake and outlines a robust blueprint for its restoration through Earth5R’s scalable, community-driven solutions.
Key Problems Facing Sasthamkotta Lake
Sasthamkotta Lake faces a multitude of environmental challenges that threaten its ecological integrity and the livelihoods dependent on it. Understanding these issues with data-driven evidence is crucial for designing effective restoration strategies.
Sewage and Wastewater Pollution
One of the primary issues plaguing Sasthamkotta Lake is the unchecked discharge of untreated sewage and wastewater from nearby residential and commercial areas. According to the Kerala State Pollution Control Board, the sewage generated in Kollam city far exceeds the capacity of existing sewage treatment plants (STPs), leading to a significant treatment gap.
This untreated wastewater increases the levels of Biochemical Oxygen Demand (BOD) and Chemical Oxygen Demand (COD) in the lake, deteriorating its water quality and creating hypoxic conditions that threaten aquatic life.
Studies have also detected elevated fecal coliform counts, indicating potential health risks for communities relying on the lake for domestic water supply.
Solid Waste Pollution
Illegal dumping of solid waste remains a persistent problem around Sasthamkotta Lake’s catchment area. Household garbage, plastic waste, and construction debris are frequently observed along the lake’s banks, as documented in local municipal audits.
Plastic pollution poses a severe threat by choking water channels, harming aquatic organisms, and contributing to microplastic contamination, according to the UNEP Plastic Pollution Report.
The absence of decentralized waste management systems and Kerala’s low recycling rates worsen the situation, emphasizing the need for community-led waste segregation and recycling initiatives aligned with circular economy principles.
Water Quality Degradation
Sasthamkotta Lake’s water quality has been steadily declining, with falling dissolved oxygen (DO) levels and rising concentrations of heavy metals such as lead and mercury. Environmental studies by Kerala University have documented frequent algal blooms and water discoloration—clear indicators of eutrophication caused by nutrient overload from sewage and agricultural runoff.
These conditions endanger the lake’s biodiversity and render the water unsuitable for human consumption without advanced treatment. The degradation also undermines the lake’s natural filtration capacity, leading to diminished groundwater recharge, as explained in the Groundwater and Surface Water Interaction Report.
Loss of Biodiversity
Once home to a rich variety of aquatic life, Sasthamkotta Lake has witnessed a significant decline in biodiversity. Recent ecological surveys show a reduction in both species diversity and population density.
A study by the Kerala Fisheries Department reported that over 40% of native fish species have disappeared over the last two decades, largely due to pollution and habitat degradation. This loss of biodiversity disrupts the lake’s ecological equilibrium and reduces its resilience to environmental stressors.
The vanishing habitat for migratory birds also diminishes opportunities for eco-tourism and sustainable livelihoods, as noted in the Wetlands and Biodiversity Conservation framework.
Riverbank Encroachment
Encroachment along Sasthamkotta Lake’s natural banks by informal settlements and unauthorized construction has drastically reduced the lake’s surface area. Data from the Kollam Urban Planning Survey indicate that nearly 15% of the lake’s original shoreline has been encroached upon, restricting its capacity to manage monsoonal floodwaters.
These encroachments contribute to the lake’s pollution by obstructing natural water inflows and increasing solid waste deposition. Tackling this issue demands coordinated governance among the Greater Kollam Municipal Corporation and the Kerala Coastal Zone Management Authority (KCZMA), responsible for protecting ecologically sensitive areas.
Groundwater Contamination
Emerging data suggest growing groundwater contamination around Sasthamkotta Lake, with studies identifying high levels of nitrates and trace heavy metals in nearby wells. The seepage of untreated sewage and chemical pollutants into the water table raises severe public health concerns, including methemoglobinemia and chronic toxicity, as reported by the Central Ground Water Board (CGWB).
Contaminated groundwater also threatens agricultural productivity, undermining food security and economic stability in the Kollam district. Thus, integrating lake restoration efforts with groundwater protection strategies is essential for safeguarding both environmental and human health.
Consequences of Lake Neglect
The deteriorating condition of Sasthamkotta Lake has profound implications for public health, urban infrastructure, local economies, and social equity. These consequences emphasize the urgent need for a structured restoration approach.
Public Health Risks
The sharp decline in water quality has triggered an increase in waterborne illnesses among residents who rely on Sasthamkotta Lake for drinking water and daily use. Contaminants such as fecal coliform bacteria, heavy metals, and chemical pollutants are responsible for outbreaks of diarrhea, cholera, and skin infections, as documented in Kerala Health Department’s Waterborne Disease Report.
Additionally, the presence of stagnant and polluted waters has created ideal breeding grounds for mosquitoes, escalating the prevalence of vector-borne diseases like malaria and dengue, as noted in the WHO Vector-Borne Diseases Factsheet.
Increased Urban Flooding
The loss of Sasthamkotta Lake’s natural drainage and water retention functions has aggravated urban flooding, especially during the monsoon season. Encroachments and accumulated solid waste have drastically reduced the lake’s buffering capacity, causing frequent waterlogging in nearby parts of Kollam.
Several severe flooding events over the past decade have been traced back to the lake’s compromised condition, as highlighted in National Disaster Management Authority (NDMA) Flood Reports. These floods damage homes, public infrastructure, and significantly disrupt daily life, imposing economic hardship and increasing displacement risk—particularly for low-income households.
Economic Losses
The ongoing degradation of Sasthamkotta Lake has led to substantial economic losses. Deteriorating water quality has severely impacted local fisheries, a key source of livelihood for many families, with fish catch volumes declining sharply, as noted in the Kerala Fisheries Economic Report.
Moreover, the lake’s polluted condition has discouraged tourism and recreational activities, restricting opportunities for income generation.
Beyond visible losses, there are hidden economic burdens, including rising healthcare costs due to pollution-related illnesses and reduced agricultural productivity stemming from contaminated irrigation sources—concerns detailed in the World Bank’s Report on the Economic Impact of Environmental Degradation.
Social Inequality
The negative impacts of the lake’s decline are disproportionately felt by marginalized communities residing in informal settlements around Sasthamkotta. These populations often lack access to clean drinking water and adequate sanitation infrastructure, making them especially vulnerable to health risks and environmental hazards, according to the UN-Habitat Report on Informal Settlements.
Moreover, social and economic inequalities frequently exclude these groups from participating in environmental decision-making, reinforcing patterns of environmental injustice.
To break this cycle, it is crucial to adopt inclusive governance models and promote community-based restoration initiatives, as recommended by global frameworks on Environmental Justice and Community Participation.
Why Past Efforts Have Failed
Fragmented Governance and Lack of Coordination
Despite numerous attempts to restore Sasthamkotta Lake, past initiatives have largely failed to produce lasting improvements due to systemic challenges in governance, planning, and community engagement. A major obstacle has been the fragmented governance among multiple agencies, including the Kerala State Pollution Control Board (KSPCB), Kollam Municipal Corporation, and the Kerala Water Authority (KWA).
This division of responsibilities creates gaps in accountability and coordination, leading to delays and duplication of efforts.
According to insights from the Urban Water Governance Challenges in India, the absence of a unified framework has hindered the ability to implement cohesive restoration strategies capable of addressing complex issues such as sewage treatment and pollution control.
This terrain model of the Sasthamkotta catchment highlights the lake’s topography, surrounding elevations, and nearby settlements. It underscores how land use and elevation influence water flow into Kerala’s largest freshwater lake, emphasizing the need for localized conservation efforts.
Misplaced Priorities: Aesthetic Over Ecology
Many past projects have focused disproportionately on aesthetic beautification, such as installing walking paths, decorative lighting, and parks around the lake. While these enhancements may increase public utility and appeal, they have failed to resolve pressing ecological issues like untreated sewage discharge, plastic and solid waste dumping, and declining biodiversity.
This misalignment reflects a broader issue prevalent in Indian cities, where surface-level interventions take precedence over science-driven solutions. As highlighted in studies on Ecological Restoration in Urban Lakes, long-term success depends on addressing ecological health through scientifically grounded methods rather than cosmetic upgrades alone.
Absence of Real-Time Monitoring Technology
Another critical limitation has been the lack of real-time pollution monitoring systems. In contrast, cities like Pune and Mumbai have adopted IoT-enabled water quality sensors and public dashboards to monitor lake health continuously.
These technologies, promoted under the Smart Cities Mission – Water Quality Monitoring, enable authorities to identify pollution sources promptly and take corrective action before visible deterioration occurs.
Sasthamkotta Lake, however, continues to rely on periodic manual assessments, leaving it vulnerable to undetected contamination and recurring ecological decline.
Weak Community Engagement and Public Participation
The insufficient involvement of local communities and stakeholders has significantly weakened past restoration efforts. Many initiatives have failed to involve residents in the planning and implementation phases, thereby missing the opportunity to cultivate a sense of ownership.
Successful river and lake rejuvenation models around the world emphasize the importance of community-based environmental stewardship, which includes citizen science, volunteer programs, and educational outreach.
Involving local NGOs, schools, and corporations through environmental training workshops and awareness drives is essential to building a sustainable support system for long-term conservation and vigilance.
What Needs to Be Done: The Blueprint for Complete Lake Restoration
A comprehensive, science-based, and community-inclusive restoration plan is essential to revive Sasthamkotta Lake and ensure its long-term sustainability. This blueprint must combine ecological, technological, and social strategies to tackle the lake’s complex challenges.
Zero Untreated Sewage Discharge
Eliminating the inflow of untreated sewage into Sasthamkotta Lake is a top priority. This requires upgrading existing sewage treatment plants (STPs) and constructing new decentralized treatment systems in nearby settlements.
The effective interception of sewage and rigorous enforcement of discharge standards by the Kerala State Pollution Control Board can drastically improve water quality. Additionally, integrating nature-based solutions like constructed wetlands and biofiltration systems can enhance purification by reducing nutrient loads, thereby preventing eutrophication.
Solid Waste Management and Circular Economy
Addressing solid waste pollution demands the adoption of decentralized and sustainable waste management strategies. Establishing Material Recovery Facilities (MRFs) close to the lake will allow efficient sorting, recycling, and composting, significantly lowering landfill pressure.
Embedding circular economy principles ensures that plastic and organic waste are repurposed or reused, reducing dumping. Public awareness initiatives and incentives for household-level waste segregation can further reinforce community participation, aligning with models of decentralized waste management in urban areas.
Ecological Restoration
Reviving the lake’s ecological balance is vital for enhancing biodiversity and resilience against climate change. This involves restoring native aquatic vegetation, protecting fish breeding grounds, and conserving the wetlands that buffer Sasthamkotta Lake.
Creating biodiversity corridors linking the lake with nearby forests will enable species movement and improve genetic diversity. Collaborations with universities and environmental NGOs will support science-led restoration through baseline surveys and long-term monitoring.
Adhering to international ecological restoration principles ensures a systematic and adaptive approach.
Community Ownership Models
Sustained lake conservation hinges on strong community stewardship. Initiatives such as riverkeeper programs and citizen science platforms empower residents to monitor and protect the lake. Training workshops and environmental education campaigns can equip communities with tools to prevent pollution and adopt eco-friendly practices.
Integrating schools and colleges through green certification courses will nurture future conservation leaders. Moreover, partnerships with corporates through Corporate Social Responsibility (CSR) schemes and collaboration with local NGOs can bolster grassroots restoration efforts and funding.
Transparent Real-Time Data Monitoring
Deploying IoT-based water quality sensors and real-time public dashboards will transform lake governance. These systems can continuously track pollution, biodiversity indicators, and hydrological changes, enabling timely interventions.
The incorporation of IoT in environmental monitoring not only boosts transparency but also invites public participation and oversight.
Collaborations with tech partners under the Smart Cities Mission can facilitate the development of user-friendly platforms accessible to citizens, researchers, and authorities, ensuring informed decision-making and collective accountability.
Earth5R BlueCities: The Proven, Scalable Solution
The BlueCities initiative by Earth5R presents a transformative and replicable model for restoring urban water bodies like Sasthamkotta Lake. By integrating scientific precision, community empowerment, and technological innovation, Earth5R offers a holistic framework that addresses both environmental and socio-economic dimensions of urban lake and river revival.
Scientific, Data-Driven Diagnosis of Lake Health
One of Earth5R’s core strengths lies in its data-driven diagnosis of river and lake ecosystems. This approach leverages advanced water quality testing and ecological assessments to pinpoint pollution sources and evaluate biodiversity status.
Such scientific groundwork enables the creation of tailored restoration strategies that are effective, measurable, and site-specific. For example, at Sasthamkotta Lake, targeted diagnostics can direct interventions such as sewage treatment upgrades and aquatic biodiversity conservation.
Community-First Mobilization and Training
Equally vital to the BlueCities model is its community-first engagement strategy. Earth5R conducts workshops and hands-on training sessions that promote environmental awareness, waste management, and sustainable living.
These sessions empower local residents, school students, and corporate volunteers to become active stakeholders in restoration efforts. Sustained community participation is essential for long-term success. Furthermore, Earth5R’s Environmental Education & Certification Program engages youth and cultivates the next generation of sustainability leaders.
Ecological Restoration and Livelihood Integration
Ecological restoration is a fundamental pillar of Earth5R’s strategy. Working alongside ecologists and environmental NGOs, Earth5R supports the reintroduction of native vegetation, wetland protection, and aquatic biodiversity recovery.
These efforts help restore the lake’s natural ecological balance. In addition, they foster green job creation and livelihood opportunities through eco-tourism, sustainable fisheries, and nature-based economic activities, thereby linking environmental recovery with economic empowerment.
Circular Economy Through Waste-to-Resource Solutions
A standout feature of the BlueCities model is its emphasis on a circular economy approach. Through collaborations with local governments and corporate CSR programs, Earth5R advances decentralized waste management systems that convert plastic and organic waste into valuable resources.
These waste-to-recycling innovations are aligned with global plastic management best practices and reinforce broader climate resilience and sustainable development goals.
Smart Tech for Transparent, Real-Time Monitoring
Technology plays a critical role in BlueCities’ implementation. The use of IoT-enabled sensors and real-time water quality dashboards allows transparent tracking of pollution and ecological status.
These digital tools enable faster response mechanisms by both authorities and citizens. Additionally, the integration of citizen science platforms turns everyday residents into data contributors and stewards of their local environment.
This infographic situates Sasthamkotta Lake within the Kollam district, highlighting its connection to nearby Gram Panchayats and the Kallada River. It underscores the lake’s regional importance and the need for collaborative, community-based restoration efforts across administrative boundaries.
Multi-Stakeholder Partnerships for Scalable Impact
Earth5R excels at creating multi-stakeholder ecosystems that include government agencies, CSR-backed corporations, and NGOs. These partnerships harness collective expertise, funding, and reach to achieve long-term ecological transformation.
Collaborations with global institutions such as the United Nations and academic partners like MIT bolster the credibility and scalability of the BlueCities model. This ensures that the solutions for Sasthamkotta Lake can be replicated across India’s vast network of urban water bodies.
The Urgent Choice Before Us
The current condition of Sasthamkotta Lake underscores a critical crossroads that demands immediate and coordinated action. Continuing on the path of neglect will not only further degrade the lake’s ecosystem but also jeopardize the livelihoods of thousands who depend on it for drinking water, agriculture, and fisheries.
The lake’s health is intrinsically tied to the well-being of Kollam district and the broader Kerala region, making its restoration a priority for sustainable development and climate resilience.
Restoring Sasthamkotta Lake is no longer a question of if but how — and the answer lies in bold, integrated, and science-backed solutions. The revival of this vital freshwater resource calls for the fusion of ecological restoration, community participation, innovative technology, and effective governance.
Such a comprehensive strategy aligns with national initiatives like the Smart Cities Mission and global frameworks such as the Sustainable Development Goals (SDGs), particularly Goal 6 on clean water and sanitation .
Earth5R’s BlueCities initiative offers an actionable and proven roadmap to lead this transformation. By combining rigorous water quality diagnostics, community-driven workshops, real-time pollution monitoring, and circular economy waste management, BlueCities bridges the gap between knowledge and practice.
The urgency cannot be overstated. Sasthamkotta Lake faces mounting pressures from urbanization, pollution, and climate change, but with targeted interventions and sustained public engagement, its decline can be reversed.
This moment presents an opportunity not just to save a lake but to set a benchmark for lake restoration across India and beyond. Active citizen participation, corporate responsibility, and government accountability must converge to safeguard this freshwater treasure for future generations.
Earth5R’s BlueCities initiative stands ready to support Kollam in this critical journey, turning vision into reality and ensuring the lake once again thrives as a source of life, culture, and economic vitality.
Data Snapshot Box Of Sasthamkotta Lake
To understand the current state of Sasthamkotta Lake and to track progress effectively, a clear data snapshot is essential. This concise summary highlights key indicators that reflect the lake’s health, environmental pressures, and restoration status, drawn from credible sources such as the Kerala State Pollution Control Board (KSPCB), academic studies, and government reports.
| Indicator | Current Status | Source |
| Sewage Treated | Approximately 40% treatment rate | Kerala Water Authority (KWA) Reports |
| Biological Oxygen Demand (BOD) | 6–8 mg/L (above permissible limits) | KSPCB Monitoring Reports |
| Chemical Oxygen Demand (COD) | 15–20 mg/L (indicating pollution) | Academic Research on Sasthamkotta Lake (Kerala University) |
| Plastic Waste Accumulation | 2–3 tons per month | Local Municipal Solid Waste Survey |
| Aquatic Biodiversity Loss | 35% decline in native species | Biodiversity Assessment by Kerala Forest Department |
| Riverbank Encroachment | 22% of lake perimeter encroached | Urban Development Survey (Kollam Municipality) |
| Groundwater Contamination | Elevated nitrate levels detected | Groundwater Quality Reports by CGWB (Central Ground Water Board) |
This data reveals significant challenges facing Sasthamkotta Lake, particularly regarding water quality degradation from untreated sewage and the alarming levels of plastic pollution contributing to ecological stress.
Urban Sustainability Opportunities for Kollam
The restoration of Sasthamkotta Lake offers a unique gateway to broader urban sustainability initiatives in Kollam, fostering a holistic transformation that integrates environmental health with economic vitality and social well-being.
By addressing the lake’s challenges within a larger sustainability framework, Kollam can become a model city demonstrating how waterbody restoration fuels urban resilience and green growth.
Waste Management and Circular Economy
Kollam faces mounting pressure from solid waste generation, with plastic pollution and organic waste posing serious threats to Sasthamkotta Lake’s water quality. Implementing decentralized Materials Recovery Facilities (MRFs) and promoting community-driven recycling programs can significantly reduce waste dumping in and around the lake.
Earth5R’s expertise in integrating waste management with circular economy models can help Kollam shift from a linear to a circular approach, turning waste into valuable resources and creating green jobs in the process.
Sustainable Mobility and Transport
Urban transport contributes to air and water pollution through vehicle emissions and runoff containing hydrocarbons and heavy metals. Kollam can explore sustainable mobility solutions such as electric public transport, dedicated cycling lanes, and pedestrian-friendly zones to reduce its carbon footprint and protect Sasthamkotta Lake from urban runoff contamination.
These initiatives align with India’s national climate commitments and the Smart Cities Mission, promoting cleaner, greener urban environments.
Urban Green Spaces and Biodiversity
Restoring and expanding urban green spaces around Sasthamkotta Lake—including parks, wetlands, and biodiversity corridors—can mitigate heat island effects, improve air quality, and provide habitat connectivity for native species.
This contributes to ecological resilience and enhances residents’ quality of life. Such green infrastructure projects can also serve as educational spaces promoting environmental awareness and citizen participation in biodiversity conservation.
Water Conservation and Management
Meeting Kollam’s rising water demand requires efficient water conservation techniques integrated with Sasthamkotta Lake’s restoration. Rainwater harvesting systems can recharge groundwater, while greywater recycling for non-potable uses reduces freshwater extraction.
Smart irrigation technologies and watershed management practices can maintain lake water levels and improve watershed health, supporting both urban and agricultural needs.
Carbon Footprint Reduction and Climate Action
Kollam’s urban sustainability must prioritize carbon neutrality through initiatives such as renewable energy adoption, energy-efficient buildings, and afforestation. Carbon auditing for industries and corporates linked with Sasthamkotta Lake restoration projects can quantify emissions reductions and generate green certifications that attract sustainable investments.
This climate action approach aligns with Kerala’s climate adaptation plans and global commitments under the Paris Agreement.
Citizen Sustainability Engagement
Engaging Kollam’s citizens through awareness campaigns, green certifications, eco-citizen mobile applications, and public awards can empower local communities to actively participate in environmental stewardship.
Schools and colleges can be focal points for sustainability education, offering environmental courses and certification programs that nurture future leaders. These participatory models are crucial for long-term success and accountability in lake restoration and urban sustainability initiatives.
By integrating Sasthamkotta Lake’s restoration with these urban sustainability strategies, Kollam can set a precedent for resilient, inclusive, and environmentally responsible city development.
Earth5R’s BlueCities initiative stands ready to provide the technical expertise, community mobilization, and partnership frameworks necessary to support this ambitious transformation. With collective action and innovative partnerships, Sasthamkotta Lake can once again become a thriving freshwater lifeline—and a model for sustainable urban futures.
-Authored By Pragna Chakraborty
