diff --git a/R/readWQPqw.r b/R/readWQPqw.r
index fb885e410b9d9ce013745dc5a03080cee4e61c5c..b5897d44c0997bd97f84d9d6efa571bf0128a884 100644
--- a/R/readWQPqw.r
+++ b/R/readWQPqw.r
@@ -24,7 +24,7 @@
 #' rawPcode <- readWQPqw('USGS-01594440','01075', '', '')
 #' rawCharacteristicName <- readWQPqw('WIDNR_WQX-10032762','Specific conductance', '', '')
 #' }
-readWQPqw <- function(siteNumber,parameterCd,startDate,endDate){
+readWQPqw <- function(siteNumber,parameterCd,startDate="",endDate=""){
 
   url <- constructWQPURL(siteNumber,parameterCd,startDate,endDate)
   retVal <- importWQP(url,TRUE)