Go back to Main

• FAQ:
  
  
  

  Any reference on the WHAT system ? WHAT Paper published in JAWRA (Lim et al.., 2005) WHAT GA - Accepted in the JAWRA (Lim et al.., 2010) How does the WHAT separate baseflow using the "Local Minimum Method" ? The "Local Minimum Method" simply connects the local minimum points by comparing the slope of hydrograph. However, the Local Minimum Method in the current WHAT system does not consider "duration of direct runoff". Therefore it could over estimates the baseflow during rainy days. Fig. 1. Hydrograph Separation using Local Minimum Method How does the WHAT separate baseflow using digital filering methods ? There are two digital filters available in the current WHAT system. One is the digital filter (Lyne and Hollick, 1979) and ther other is the Eckahrdt filter (Eckhardt, 2005). If you need details regarding these filters, please refer to the WHAT Paper published in JAWRA (Lim et al.., 2005) What is the differences betweeen WHAT Mapserver and WHAT Google Map versions ? There is no significant differences between two versions. However, WHAT Google Map version will be maintained from now on. Is the WHAT accurate enough compared with the results from the BFLOW digital filter ? Please click here to see the accuracy estimation result using the WHAT digital filtering method. Can I use the Hourly flow data for baseflow separation using the WHAT system ? Yes, you can use either "i) I will ENTER my flow data" or ii) I will UPLOAD my flow data option for hourly baseflow separation. The "iii) HOURLY version - USGS Hourly Flow Database" is developed for USGS Hourly flow database. Who I can contact for general questions and technical issues in the WHAT system ? If you have any questions regarding the WHAT system, please send email to Dr. Bernie Engel or Dr. Kyoung Jae Lim .