# Tag : Time of Concentration

## Design A Detention Basin Using SCS Hydrology in HydroCAD

A previous post introduced the design of a detention basin using Modified Rational Method in HydroCAD, and this post is about detention basin design using SCS hydrology in HydroCAD. The…

## Basin Development Factor (BDF) and Its Application in Urban Hydrology

Urbanization has some substantial impacts on a watershed hydrology including increased surface runoff flow rate and volume, quicker to peak, decreased infiltration and evapotranspiration. To account for these effects in…

## Rational Routing in InfoWorks ICM

In addition to various unit hydrograph transform methods and SWMM nonlinear reservoir runoff method, InfoWorks ICM also has a built-in rational routing model for rainfall-runoff process. To utilize the Modified…

## SCS Curve Number Method and Its Application in HEC-HMS, XPSWMM, and InfoWorks ICM

SCS Curve Number (CN) method, proposed by USDA Soil Conservation Service (SCS, now known as NRCS), has been widely used for infiltration loss and runoff calculation due to its simplicity…

## Time of Concentration (TOC) Estimation

Time of Concentration (TOC or Tc), one of the most important hydrologic parameters for runoff calculation and modeling, is defined as the time it takes a drop of rainfall to…

## Modified Rational Method Application in HydroCAD and XPSWMM

HydroCAD and XPSWMM have the modified rational method built into the programs and it is very convenient to apply the method in either of the modeling tools. One or more…

## Rational Method and Modified Rational Method – Peak Flow and Hydrograph

For small drainage areas, the rational method is widely used to calculate peak flows of different drainage design levels to size storm sewer, inlets, culverts, and ditches. The rational method…

## Calculate Longest Flow Path Using Whitebox Tools (WBT) Plugin in QGIS

Time of concentration (TOC) is an important hydrology parameter which represents the time required for surface runoff to travel from the most hydraulically remote point (normally divide or ridge) in…