TN-49: Storm drainage estimation in urban areas

Abstract

In the last few decades, the world has witnessed rapid urbanisation. One of the many complex problems which have come up with increased urbanisation is that of quick drainage of storm water from the inhabited areas. For the design of an efficient and economic urban drainage system, it is important to estimate the design runoff with a good degree of accuracy.

In India, the present practice of urban runoff estimation is based on empirical formulae and not adequate for the analysis and design of complex drainage systems. A good amount of research work has been done in economically developed countries in the field of urban drainage and a number of models have been developed, tested and verified, conceiving the urban watersheds as systems.

In this technical note, an attempt has been made to review the various urban drainage models developed in different countries with their merits and demerits. The present practices of urban runoff estimation in India have been examined and the necessity of recording & maintenance of hydrological data for urban areas has been emphasised.