EVALUATION OF SEWERAGE SYSTEM AT HARIDWAR

Abstract

Due to explosive population growth and concomitant urbanization the sewerage system is being increasingly overloaded. In many cases, sewerage systems are not able to work for its design life. In a country like India, sewerage systems in almost every important city/town needs renovation in about 10-15 years, though,the design period of projects is 25 to 30 years. In view of this, an attempt has been made in the present work to evaluate waste water collection system (WWCS) at Harilwar-Rishikesh. It was also desired to assess, whether Ganga Action Plan (GAP) launched at Haridwar-Rishikesh in 1985, is fulfilling its objectives. For evaluation of sewerage system at Haridwar-Rishikesh, all important parameters like population estimation, intercepting factor, peak factor, capacity of sewers, sump, pump and treatment plant have been considered. For evaluation purposes, present trend of population (based on observed flowdata), intercepting factor, peak factor etc. are compared with those set in strategy report of GAP for Haridwar-Rishikesh. In Haridwar, out of two sewage outfalls- only MPS Jagjeetpur has been considered as it cares for major and important sewerage zones. Out of nine zones that comprises Haridwar Union, Kankhal (Zone D) has been assumed as a representative zone and evaluated. Similarly for Rishikesh V Union, only Mayakund zone has been evaluated. Based on evaluations and analysis of sewage flow data, peak factors have been calculated which are more than those adopted in design of sewerage systems. An attempt has also been made to compare these values with those set in code, "Manual on Sewerage and Sewage Treatment". These values were generally found on conservative side. From observed sewage flow data, sustained peak factor curves have been developed. The sustained peak factor curves are currently being used for design of treatment facilities whereas peak factor for WWCS. Apart from these, the impact of 1,7AP has also been studied on Haridwar-Rishikesh.Usefulness of GAP has also been indicated for preventing Ganga from severe pollution.