Open-File Report 2009-1138
Natural flow regime concepts and theories have established the justification for maintaining or restoring the range of natural hydrologic variability so that physiochemical processes, native biodiversity, and the evolutionary potential of aquatic and riparian assemblages can be sustained. A synthesis of recent research advances in hydroecology, coupled with stream classification using hydroecologically relevant indices, has produced the Hydroecological Integrity Assessment Process (HIP). HIP consists of (1) a regional classification of streams into hydrologic stream types based on flow data from long-term gaging-station records for relatively unmodified streams, (2) an identification of stream-type specific indices that address 11 subcomponents of the flow regime, (3) an ability to establish environmental flow standards, (4) an evaluation of hydrologic alteration, and (5) a capacity to conduct alternative analyses. The process starts with the identification of a hydrologic baseline (reference condition) for selected locations, uses flow data from a stream-gage network, and proceeds to classify streams into hydrologic stream types. Concurrently, the analysis identifies a set of non-redundant and ecologically relevant hydrologic indices for 11 subcomponents of flow for each stream type. Furthermore, regional hydrologic models for synthesizing flow conditions across a region and the development of flow-ecology response relations for each stream type can be added to further enhance the process. The application of HIP to Missouri streams identified five stream types ((1) intermittent, (2) perennial runoff–flashy, (3) perennial runoff–moderate baseflow, (4) perennial groundwater–stable, and (5) perennial groundwater–super stable). Two Missouri-specific computer software programs were developed: (1) a Missouri Hydrologic Assessment Tool (MOHAT) which is used to establish a hydrologic baseline, provide options for setting environmental flow standards, and compare past and proposed hydrologic alterations; and (2) a Missouri Stream Classification Tool (MOSCT) designed for placing previously unclassified streams into one of the five pre-defined stream types.
First posted November 17, 2009
For additional information contact:
Part or all of this report is presented in Portable Document Format (PDF); the latest version of Adobe Reader or similar software is required to view it. Download the latest version of Adobe Reader, free of charge.
Kennen, J.G., Henriksen, J.A., Heasley, John, Cade, B.S., and Terrell, J.W., 2009, Application of the Hydroecological Integrity Assessment Process for Missouri Streams: U.S. Geological Survey Open-File Report 2009–1138, 57 p.
Seminal Hydroecological Research
Study Area Description
Stream Classification and Selection of Indices
Hydroecological Integrity Assessment Software
Appendix 1. Stream type and characteristics of gaging stations representing relatively unimpaired basins used to classify Missouri streams
Appendix 2. Definitions for the 171 Hydrologic Indices