Sanitation and wastewater management for health in Chengalpattu, Tamil Nadu, India

Chengalpattu, Tamil Nadu, India

In collaboration with

World Vision

August 2020 – March 2021

We install the DEWATS waste treatment system at Chengelpattu District Government Medical College and Hospital with the two women’s student hostels and community homes living near the hospital.


  • To provide a sustainable sewage treatment facility for the District Government Hospital currently treating COVID-19 using DEWATS Approach (Decentralized Waste Water Treatment System) to reduce contamination of community underground water
  • To train hospital staff on operation & maintenance of DEWATS system


3000 direct
500 children under 15 and 1500 women.

4,000 indirect
People living in close proximity to the hospital campus.

Project image

On the ground

The discharge of hospital wastewater that needs treatment is very high, and its open runoff into communities is a significant risk to people’s health.

The District Government Hospital & Medical College is a 1,300 bed facility and provides free healthcare to communities mostly to low income groups. The hospital has 2 blocks for Comprehensive Emergency Obstetric and New Born Care (CEMONC) with inpatients, and 2 women’s hostels for women students and in house staff.

All waste water from these buildings are not collected or treated in sanitation systems and instead let our into the open behind the hospital campus. The constant flow of waste untreated water is a high risk factor for groundwater contamination and health hazard to the community around.

In detail

DEWATS is a biological wastewater treatment system which functions through natural and biological degradation of organics by anaerobic microorganisms. DEWATS technology is based on the principles of “nature based”, “low operation and maintenance cost”, “constructed using locally available” and functions “without or less external energy inputs or mechanical devices”. DEWATS modules are based on sedimentation, anaerobic digestion in suspension and in fixed beds, aerobic digestions and polishing treatments.

This Project will undertake the installation of a waste water treatment system through the DEWATS approach for one CEMONC building. This would include setting up of a facility involving either prefabricated or concrete waste treatment chambers to treat the water.

Preliminary needs identification visits have been held with the Hospital’s Dean, Administrative Head, Senior Heads of Departments, and the Public Works Department of the District’s Municipal Corporation. The process of DEWATS and its benefits have been briefed in detail to the Hospital. The Hospital has given full support for the project in writing. The Public Works Department has issued a no-objection for undertaking this project.

The project will include necessary assessments and water quality checks before and after implementation. The completed project will be inaugurated and handed over to the Government authorities for necessary operation and maintenance. Required training to the Government staff for sustainability will be given through the project.

The project also plans to engage with the students of the hospital, the Student’s Green Club and the Group D grade of maintenance staff and train them on the DEWATStechnology. Adequate training and handholding for operation & maintenance will be provided through the project.

Perspectives of sustainability

The DEWATs functions with nature based waste water treatment methods. The operation cost to the facility is very negligible compared to conventional sewage treatment plants as there is no machinery involved. Maintenance would mostly include removal of accumulated sludge once or twice a year and routine checking the tanks for potential clogging due to sanitation products like napkins etc wrongly disposed by the hospital’s inmates.

This maintenance can be easily done by one assigned existing staff of the hospital. A maintenance schedule can be maintained by the hospital’s administration department for routine cleaning of the sludge from the chambers and tanks.

The hospital senior staff and maintenance staff will be adequately trained with technical expertise at the time of commissioning the project.