In Thiruvananthapuram Corporation only 30% area is covered by the underground sewerage system. The system was installed 30 to 35 year ago. The system services a total of 75,000 connections. The households in the remaining areas depend on various on-site systems namely, septic tanks, borehole latrine TUDP and community toilets with 8% of the population do not have access to safe sanitation disposal.
The main drainage basin of major water bodies of the city are Vellayani Lake and Parvathi Puthanaar. The sewage is disposed at the Muttathara Sewage Treatment Plant, which handles 32 million liters per day. The city area is divided into seven blocks for the execution of the sewage system, two commissioned in the 1990s and two after 2000. The sewerage was pumped to a stilling chamber at the Sewerage Treatment Plant (STP) at Valiyathura and is disposed through sewage farms.
Excavation of hillocks and leveling of low-lying land occurring in and around Thiruvananthapuram city is a major issue. The wetlands and paddy fields are ruthlessly reclaimed for erecting buildings causing an increase in surface runoff, affecting the natural drainage system. There are a number of trough areas not connected with water bodies within the city causes flooding. This causes triggered floods in different areas and main transit centers like Thampanoor and East Fort in the city which are lying in the downstream. This shows there is a lack of properly linked water retention areas within the city.
The present system of disposal of sewage is functioning based on the obsolete technology of fodder farming and which is unable to treat the increasing sewage load reaching the farm area. Hence the entire sewerage system is practically defunct, with raw sewage finding its way through punctured manholes and leaky sewer lines, ultimately dumping into open yards or surface water bodies. A complete unhygienic condition prevails in and around the sewage farm area. Only 10 to 15% of untreated sewage is utilized for fodder grass cultivation and the rest is discharged either directly into Parvathy Puthanar or into open lands which indicate the very magnitude and extent of pollution likely to affect the neighbouring areas.
All these factors are the constraints for the waste water treatment of the city. We need a well-planned sewage system for replacing the old system established throughout the city. In order to that, we require a complete mapping of sewage network.
Please post suggestions and smart ideas to eliminate these problems....