Last Modified: Last Modified: 2025-04-24 08:42:50.688

Software

The HEC-SSP team is nearing completion of the Peaks Over Threshold analysis in HEC-SSP. Download a temporary build of HEC-SSP here to access the analysis for this workshop. Note that this build is different than the v2.3.1-beta.1 version that is on HEC's website. Please save this build in the same directory as the HEC-SSP study that you will create in this workshop.

Initial Workshop Files

SanLorenzoStreamflow.dss

Overview

In this workshop, you will become familiar with filtering criteria (threshold selection, time separation, and magnitude differential) methods that are available within HEC-SSP. Spend approximately 10 minutes on Task 1, 20 minutes on Task 2, and 20 minutes on Task 3:

If you are interested in repeating this workshop using R, see Flood Separation and Threshold Choice Workshop.

Note that there are known differences between HEC-SSP's Data Filterer and the R POT package's clust function. For a given time separation criterion, HEC-SSP's Data Filterer and the R POT package's clust function will provide slightly different partial duration series.

HEC-SSP's Data Filterer has been extensively validated and employs a more accurate filter than the clust function.

Background

This workshop will explore the sensitivity of the results of a peaks over threshold analysis to the choice of the threshold and the criteria for separating flood events. You will be working with daily average streamflow data for the San Lorenzo River near Big Trees, CA (11160500) in Santa Cruz County. The San Lorenzo River has a drainage area of 106 square miles at this gage and drains into the Pacific Ocean at Santa Cruz.  

Final Workshop Files

SanLorenzo_POT.zip

Continue to Task 1. Import Data and Create a Peaks Over Threshold Analysis.