Abstract

Background: Tiruchirappalli, is the fourth largest corporation in Tamil Nadu, India. The city is partially sewered, covering 30 per cent of households. On-site sanitation systems (OSS) such as septic tanks, holding tanks, and single pits are the predominant arrangement in urban households in the city. Regardless of settlement characteristics, wastewater is often discharged into open drains, water sources, or adjacent lands, leading to unsanitary conditions. This study aimed to understand the approval and construction process of OSS as prescribed in the Tamil Nadu Combined Development Building Rules (TNCDBR) and on-ground practices, to identify reasons for such practices.

Methods: The TNCDBR rules for building plan approval were studied, and a representative sample of 40 households that received plan approval one year prior to the study was selected based on Urban Local Body (ULB) records. Approved plans in these households were compared against Indian Standards (IS) standards for the construction of OSS and actual structures to identify the deviations. Additionally, surveyors, engineers, government officers, and households were interviewed to understand their practices and perspectives. The study was conducted between October 2021 and January 2022.

Key Findings: The TNCDBR mandates the submission of OSS design and dimensions as defined by the IS, but in practice, the urban local body (ULB) uses a software that merely checks the provision of a sanitation structure in the plan, and specifications vis-à-vis standards and disposal arrangements are not reviewed at the plan approval stage.

TNCDBR requires the corporation to be notified during specified stages of construction, and a building completion certificate is issued upon compliance with the approved plan during site inspection. However, in practice, ULB officers are not notified during construction progress, and most site inspection occur when two thirds of the construction is complete. At this stage, ULB officers review the built-up area vis-àvis the approved plan and issue deviation notices if any and impose fines, which clients choose to pay off because addressing deviation at this stage is difficult. During inspection, OSS is often not yet constructed and even if it is, deviations are not reflected in the deviation notice. Typically, OSS is constructed based on available offset and as per Vaastu, a traditional Indian practice for building design and architecture.

In the sampled households, many deviations in actual OSS from IS standards and the approved plan were noted. Ninety per cent of OSS do not comply with IS standards. Further, deviations from the 147 approved plan in terms of designs variations (80 per cent), location deviations (50 per cent), disposal arrangements (40 per cent) were noted. Stakeholders point to the high cost of land as a reason for deviations.

Conclusion: This study highlights gaps in the implementation of TNCDBR at the approval and inspection stages. It calls for bridging the gap between TNCDBR and actual approval and inspection practices and strengthening urban local governance structures to effect improved sanitation outcomes. Additionally, all stakeholders in the building plan approval process need to be sensitised on the importance of constructing OSS as per standards and its environmental and health benefits.