Assessment of high-value near-term engineering innovations for Indian sanitation

Abstract

This study presents the Sanitation Needs and Innovation (SaNI) framework for identifying underserved populations and gaps between their sustainable sanitation requirements and sanitation system performance. Safe, sustainable sanitation is a vital, frequently unmet need - especially in low and middle-income countries. In India alone, economic losses from poor sanitation are estimated to be $53.8 billion annually, or 6.4% of the country's 2006 GDP. Too often, sanitation solutions fail to address the full problem due to the complexity of constraints imposed by the environment, available technology options, and the many different stakeholders involved. Several frameworks have been established to distill possible solution paths, such as technoeconomic analysis and multi-criteria analysis (MCA). However, technoeconomic analyses alone do not consider the multitude of other facets that contribute to sustainable sanitation, and MCAs are often very context-specific, non-quantitative, and used primarily for comparative purposes. The SaNI framework enables analysis of cost of sanitation systems vs. population density to yield underserved populations and perform an MCA-like analysis to determine whether other, non-monetary, sustainable sanitation requirements are met. A case study applying this framework to the Indian context identifies population densities between 10,000 and 23,000 people/km² as regions where current technologies fail to meet cost requirements. The test case demonstrates quantitatively that septic tanks, a ubiquitous on-site sanitation method, are likely to be unsuitable for people with lower-than-average available land areas and abilities to pay. By quantifying the deficiencies of current sanitation technologies, the proposed framework can guide the development of the next generation of truly sustainable solutions.