\documentclass[10pt]{article}

\usepackage{fullpage}
\usepackage{setspace}
\usepackage{parskip}
\usepackage{titlesec}
\usepackage[section]{placeins}
\usepackage{xcolor}
\usepackage{breakcites}
\usepackage{lineno}
\usepackage{hyphenat}





\PassOptionsToPackage{hyphens}{url}
\usepackage[colorlinks = true,
            linkcolor = blue,
            urlcolor  = blue,
            citecolor = blue,
            anchorcolor = blue]{hyperref}
\usepackage{etoolbox}
\makeatletter
\patchcmd\@combinedblfloats{\box\@outputbox}{\unvbox\@outputbox}{}{%
  \errmessage{\noexpand\@combinedblfloats could not be patched}%
}%
\makeatother


\usepackage{natbib}




\renewenvironment{abstract}
  {{\bfseries\noindent{\abstractname}\par\nobreak}\footnotesize}
  {\bigskip}

\titlespacing{\section}{0pt}{*3}{*1}
\titlespacing{\subsection}{0pt}{*2}{*0.5}
\titlespacing{\subsubsection}{0pt}{*1.5}{0pt}


\usepackage{authblk}


\usepackage{graphicx}
\usepackage[space]{grffile}
\usepackage{latexsym}
\usepackage{textcomp}
\usepackage{longtable}
\usepackage{tabulary}
\usepackage{booktabs,array,multirow}
\usepackage{amsfonts,amsmath,amssymb}
\providecommand\citet{\cite}
\providecommand\citep{\cite}
\providecommand\citealt{\cite}
% You can conditionalize code for latexml or normal latex using this.
\newif\iflatexml\latexmlfalse
\providecommand{\tightlist}{\setlength{\itemsep}{0pt}\setlength{\parskip}{0pt}}%

\AtBeginDocument{\DeclareGraphicsExtensions{.pdf,.PDF,.eps,.EPS,.png,.PNG,.tif,.TIF,.jpg,.JPG,.jpeg,.JPEG}}

\usepackage[utf8]{inputenc}
\usepackage[english]{babel}



\usepackage{float}








\begin{document}

\title{Developing Customized NRCS Unit Hydrographs for Ungauged Watersheds in
Indiana, USA}



\author[1]{Tao Huang}%
\author[1]{Venkatesh Merwade}%
\affil[1]{Purdue University}%


\vspace{-1em}



  
  \date{May 26, 2024}


\begingroup
\let\center\flushleft
\let\endcenter\endflushleft
\maketitle
\endgroup





\selectlanguage{english}
\begin{abstract}
The Natural Resources Conservation Service (NRCS, formerly the Soil
Conservation Service, SCS) unit hydrograph (UH) is one of the most
commonly used synthetic UH methods for hydrologic modeling and
engineering design all over the world. However, previous studies have
shown that the application of the NRCS UH method for some ungauged
watersheds in the state of Indiana produced unrealistic flood
predictions for both the peak discharge and the time to peak. The
objective of this work is to customize the NRCS UH by analyzing the role
of its two key parameters, namely, the peak rate factor (PRF) and the
lag time, in creating the runoff hydrograph. Based on 120
rainfall-runoff events collected from 30 small watersheds in Indiana
over the past two decades, the observed UHs are derived and the
corresponding PRF and lag time are extracted. The observed UHs in
Indiana show that the mean value of PRF is 371, which is lower than the
standard PRF of 484, and the NRCS lag time equation tends to
underestimate the ``true'' lag time. Moreover, a multiple linear
regression method, especially the stepwise selection technique, is
employed to relate the NRCS UH parameters to the most appropriate
geomorphic attributes extracted from the study watersheds. Both the
statewide and regional regression models show that the main channel
slope is a major factor in determining the PRF and lag time. A
customized Indiana unit hydrograph (INUH) is derived with updated
parameters and the Gamma function. Validation results show that the INUH
provides more reliable and accurate predictions in terms of the peak
discharge and the time to peak than the original NRCS UH for the
watersheds in Indiana.%
\end{abstract}%



\sloppy




\selectlanguage{english}
\FloatBarrier
\end{document}

