An assessment of the rational method's limitations for calculating runoff in Islamabad's urban areas: A Case Study EMAAR Housing Society

Abstract

Peak discharge estimate is often done using the rational method. Because ground properties
and precipitation rates vary, many writers have identified differences in catchment areas that limit the
application of the rational technique in different regions. The researchers generally said that this strategy
might yield findings that are acceptable within 200-acre limits. Nevertheless, in order to verify the
applicability and catchment constraints for the future design of storm drainage systems, it is necessary to
assess the applicability of rational approaches with regard to catchment area for the Islamabad region.
Various places of interest were established, each with drainage areas measuring 663.8 acres, 805.4 acres,
1056.9 acres, and 1529.0 acres. All sites of interest have their corresponding discharge values determined
using the rational technique. The outcomes were then contrasted with the same catchments using the soil
conservation service (SCS) curve number approach. Comparing the data, it was evident that the Rational
Method technique would be more appropriate for developed regions, or bigger areas with different terrain
and area types. Upon completion of this research project, readers will possess the capacity to assess the
suitability of the rational method.