1. Overview of HEC Data Storage System (HEC DSS)
Dr. Sangam Shrestha
Associate Professor and Chair
Water Engineering and Management
Asian Institute of Technology
Training on Hydrological Modelling for Water Accounting
Asian Institute of Technology, Thailand
December 18-24, 2017

2. Objectives to introduce HEC Data Storage System
to develop the skills of participants to use HEC Data Storage System

3. Contents What is HEC DSS? HEC DSS Application
Path Name and its description
HEC DSS data types
HEC-DSSVue Main Window

4. What is DSS?
The Hydrologic Engineering Centre’s (HEC) data storage system visual utility engine (HEC-DSSVue) is a graphical user interface program for viewing, editing, and manipulating data in the HEC data storage system (HEC- DSS) data base files
HEC-DSS is a data base system designed primarily for Water Resource applications
HEC-DSSVue is written using Java Programming language that allows it to run under variety of different operating systems

5. What is DSS? The HEC-DSS system consists of:
Package of high-level language subroutines or functions to interface with computer programs
Set of support utilities
DSS files (direct access files)
Data is stored in records or blocks within the file
Records are identified by path names
Header array stores additional information

6. DSS Application Storing and maintaining data in a centralized location
Providing input to and storing output from application programs
Transferring data between application programs
Displaying the data in graphs and tables

7. HEC DSS Pathname HEC-DSS pathnames
Up 80 characters
Separated in six pathnames
A/B/C/D/E/F
Pathnames are used to index position with in the DSS file

8. Naming Convention for Pathname Parts
Description A
Project, River, or Basin Name B
Location C
Data Parameter D
Starting Date of Block E
Time Interval F
Additional User Defined Description

9. Pathname Parts Part A: Group
Usually this information is watershed name, study name, project, river or basin name
Part B: Location
Part B is required for regular and irregular interval time series data and is the basic location identifier, which is generally the site name, i.e.. gauge ID, project ID
Part C: Parameter
Part C identifies the basic data parameter for regular and irregular interval time series data. ie. Flow, Precip, PH, Temp
Part D : Block Start Date
Part D identifies date of the data block .i.e.. 01jan1980

10. Pathname Parts Part E- Time Interval
Part E consist of an integer number and an alphanumeric time interval specifying the regular data interval. Valid alpha entries are MIN, HOUR, WEEK, MON, YEAR
Part F- Description
Part F used to provide any additional information about the regular and irregular time series data.

11. HEC-DSS Data Types Keyword Meaning Example PER-AVER Period Average
Daily Flow
PRE-CUM
Period Cumulative
Monthly Flow (volume)
INST-VAL
Instantaneous
Stage
INST-CUM
Instantaneous Cumulative
Rain mass curve

12. HEC-DSSVue Main Window

13. File Edit View Display Menu Bar
File menu includes new project set up, open project, close project, print preview, print and exit
Edit
Edit menu used for Table edit, graphical edit, edit in excel file, select all, rename, copy, duplicate delete, undelete etc.
View
View menu allows to customize the display of HEC-DSS pathnames
Display
Display menu used for plot, tabulate etc

14. Data Entry Tools Menu Bar This menu is used to add data files to DSS
Tools menu provides tools for manipulating DSS record, include math function

15. Q & A

16. Thank you!
Dr. Sangam Shrestha