Solving Water Scarcity and Pollution: A Sustainable Solution for Sulur City, Tamil Nadu

By Prathamesh & Karl

Teamcode: YA-DK-1


In recent years, the city of Sulur, located near Coimbatore in the state of Tamil Nadu, India, has been grappling with a range of pressing issues. Water scarcity, open defecation, and the contamination of surface water have become significant challenges for the local community. Furthermore, the Noyyal River, a lifeline for the region, carries a heavy burden of sludge and pollutants from Coimbatore, negatively impacting the semi-urban area of Sulur, where agriculture thrives. However, a promising solution has emerged that aims to address these problems through a community-driven approach, supported by political will and sustainable practices.

The Problem at Hand

Sulur city faces a threefold challenge: water scarcity, inadequate sanitation facilities, and the contamination of the Noyyal River. The scarcity of water resources has severely affected the daily lives of residents, causing hardships in meeting their basic needs. Additionally, open defecation has resulted in unhygienic conditions, further exacerbating the risk of diseases. Perhaps most distressing is the pollution of the Noyyal River, which not only affects the ecosystem but also impacts the agricultural activities that form the backbone of Sulur’s economy.

A Community-Driven Solution

To combat these issues, a comprehensive solution is being proposed, one that emphasizes community inclusion and harnesses the political will to achieve desirable results. The focal point of this solution is the establishment of decentralized sewage treatment plants along the banks of the Noyyal River. These plants will process the sewage generated by households in Sulur city, effectively transforming it into treated water and nutrient-rich manure.

Technical overview

The choices of technologies are picked from the sanitation part of the eCopendium known as the Emergency WASH Knowledge Portal. When we first menion one of the technologies we will provide a link for the reader that wants to learn about it in more depth.

Groups of roughly 20 houses will share a septic tank used to have their blackwater separated into cleaner liquid effluent and solid settled sludge. Sludge and effluent is then transported to a decentralised treatment plant where sludge gets to dry for a few years in planted drying beds until it is ready to be applied as manure. Effluent and greywater is instead treated in constructed wetlands until it is safe enough to use for irrigation.

If we have more area available we can start treating the surface water from the nearby lake or river, by pumping it into settlers, which again separates the water into effluent and sludge.

This figure showcases how each technology relates to each other through the flow of sludge and affluent throughout the system. The dotted line represents the treatment of river water.

By making a few assumptions we some numeric expectations for how effective this system will be. These values can be seen in the table below.

Treated Manure Produced [Kg/year]66’680
Effluent Cleanedm [L/day]4’000’000
Space Treatment space required [Ha]20
Additional treated rivereffluant [L/Ha]200’000
Additional treated river manure [kg/(L*Ha)]1’600
In the above table we see the amount of generated resources.

Maximizing the Benefits

The treated water and manure produced by these sewage treatment plants offer substantial opportunities for optimization. In this proposed model, 70% of the treated water and manure will be made available for sale to Agriculture and Industries, thereby generating revenue for the region. This innovative approach not only addresses the water scarcity issue but also provides a sustainable income stream. The remaining 30% of the treated water and manure will be distributed back to the villagers, enabling them to utilize it for irrigation and agricultural purposes. This dual approach ensures that the benefits of the project are shared among the community and industries alike.

Possitive outcomes

First and foremost, the primary benefit of a better sanitation system is of course the improved health benifits brought to the community, Having well maintained sanitation available is the best way to end any sort of open defication, which has both long and short o

By implementing this project will see a substantial impact on the pollution and contamination levels of the Noyyal River. By treating sewage at the decentralized plants, the sludge and pollutants that previously burdened the river will be significantly reduced, leading to a cleaner and healthier ecosystem

Sulur city can witness a significant transformation in its natural environment. The restoration of the Noyyal River, improved sanitation facilities, and the creation of recreational spaces along the riverbanks will enhance the overall aesthetics of the city. The rejuvenation of the river and the creation of green spaces will attract tourists who seek to experience the beauty of nature, indulge in outdoor activities, and enjoy a serene environment.

The revenue from this tourism as well as from the sale of treated water and manure will inject much-needed funds into the region. These funds can be utilized to develop essential infrastructure and create recreational spaces along the banks of the Noyyal River. The provision of improved facilities and public spaces will enhance the quality of life for the local residents and promote a sense of community well-being.

Limitations and future concerns

  • We need to consider how we are going to transport so much water. It may be the case that the effluent from the blackwater can be disposed of in situ with soaking pits, which may allow us to transport the less hazardous greywater through stormwater drains.
  • Both the planted drying beds and the constructed wetland generate biomass, which we need might want to find a use for, we could maybe cocompost it with untreated sludge to complement the drying beds.
  • We have to decide on what kind of constructed wetland we want to create, which may give us a more precise area measurement.
  • Instead of just assuming a water supply 100 L/Day we should take a closer look at how people get there.
  • Is our treated water safe enough for bathing or even drinking?
  • While we are proposing irrigation technology we should consider whater it is possible to also make sure the agriculture is using more water-efficient microirrigation, and if not, we should consider if there are ways we could encourage this.
  • We have to consider that water treatment near Sulur may not be enough to clean the river by itself as there are major pollution sources near futher upstream. But by utilizing the treatment system we will be able to prove the potential effect through water meassurements, and the general system idea should be possible to impliment throughout other villages near the Noyyal.

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