Surface Water Quantity Baseflow Baseflow Separation

Requirements

1. Daily streamflow time series
2. Software such as the Hydrograph Separation Program

How does software-based separation work?

Hydrograph separation traditionally has been done manually. Different hydrologists using the same manual hydrograph-separation method commonly produce different base-flow estimates. The use of a computer program removes inconsistencies inherent in manual methods and substantially reduces the time required for hydrograph separation. Separation of a streamflow hydrograph is based on a mathematical technique that mimics the way that humans have been separating hydrographs, rather than on the physics of the process. Thus, although a hydrograph separation software such as HYSEP consistently applies various algorithms that are commonly used for hydrograph separation, hydrograph separation remains a subjective process.

More complex and process-based algorithms are also available for baseflow estimation such as the Recursive Digital Filtering Method.