IAHR, founded in 1935, is a worldwide independent member-based organisation of engineers and water specialists working in fields related to the hydro-environmental sciences and their practical application. Activities range from river and maritime hydraulics to water resources development and eco-hydraulics, through to ice engineering, hydroinformatics, and hydraulic machinery.
Log On
About IAHRDirectoryCommitteesMy IAHRNews & JournalseLibraryeShopEventsJoin IAHRWorld CongressDonate
spacer.gif eLibrary
spacer.gif eLibrary
You are here : eLibrary : IAHR World Congress Proceedings : 36th Congress - The Hague (2015) ALL CONTENT : Water engineering : New methods for quantifying effective impervious area in urban watersheds
New methods for quantifying effective impervious area in urban watersheds
Author : Ali Ebrahimian1, John S. Gulliver2, Bruce N. Wilson3
Although total impervious area (TIA) has been traditionally used as an indicator of urban
disturbance, recent studies suggest that a better indicator of urban runoff is the ˇ°effectiveˇ±
impervious area (EIA), or the portion of total impervious area that is hydraulically connected to
the storm sewer system. EIA can be considered the most important parameter in determining
urban runoff, and knowledge of EIA is therefore critical in rainfall-runoff modeling. The
incorrect use of TIA instead of EIA in urban hydrologic modeling leads to an overestimation of
runoff volumes and rates (Alley and Veenhuis, 1983). Also, directly connected impervious areas
are the primary contributing area for smaller storms and therefore, the main concern for water
quality (Lee and Heaney, 2003). The most accurate method for quantifying EIA in urban
watersheds is supposed to be the statistical analysis of rainfall-runoff data sets (Boyd et al., 1993;
1994), because it is based on observed data. Without a good comparison to EIA determined from
rainfall and runoff data, the other techniques to measure EIA (e.g. GIS techniques) cannot be
verified. Methods to improve estimates of EIA are not highly researched, and need further
File Size : 280,981 bytes
File Type : Adobe Acrobat Document
Chapter : IAHR World Congress Proceedings
Category : 36th Congress - The Hague (2015) ALL CONTENT
Article : Water engineering
Date Published : 20/08/2015
Download Now