HEC-GridUtil is designed to provide viewing, processing, and analysis capabilities for gridded data sets stored in HEC-DSS format (Hydrologic Engineering Center's Data Storage System). Sequences of grids typically approximate the variation through space of a quantity measured varying through fixed-intervals of time at fixed locations. The predominant types of gridded data in DSS are regular-interval time-series of hydrologic variables, such as Stage 3 NEXRAD (Next Generation Radar) precipitation or mean daily air temperatures throughout a basin.

Time-series of spatial information have become increasingly important to mainstream hydrological applications, but they pose challenges regarding standardized storage and indexing. The structure of gridded data in HEC-DSS provides very efficient storage and retrieval of data sets that contain a single parameter, expressed in the same units, covering the same grid cells (in terms of spatial extent and coordinate definition), and a constant time interval.

Storage in HEC-DSS primarily facilitates use of the data by the HEC-HMS (Hydrologic Engineering Center's Hydrologic Modeling System) model and the CWMS CAVI (Control Acquisition Visualization Interface), but also provides advantages regarding access speed, data organization, file size, portability, multi-platform support, and avoidance of requirements for licensing proprietary software.