7812

• UCREFRP Catalog Number: 7812
• Author: Many
• Title: Rivers, Studies in the Science, Environmental Policy, and Law of Instream Flow
• USFW Year: 1990
• USFW - Doc Type: Rivers
• Copyright Material: YES

Managing Riverine Values and Uses
Laurence R. Jahn
President, Wildlife Management Institute
Washington, D.C.
For most of U.S. history, water in rivers was used for navigation, transportation, and
disposal of wastes. Water has also been appropriated for a variety of out-of-channel
uses. With continuous growth of the human population, demands on river systems
and other features of the resource base have expanded substantially. As the U.S. pop-
ulation. approached and surpassed 200 million, people gradually came to recognize
that unbridled' demands for water in rivers are not in the best public interest. Too many
values and uses assumed to be never-ending have become threatened with degradation,
and some have been lost.
Realization of pressing needs for managing river systems to perpetuate a variety of
values and uses began to sharpen in the 1970's. This growing interest stimulated new
advances in science and law to build a solid factual foundation on which to construct
a stronger framework of legal authorities and administrative procedures for improving
integrated management of river systems.
In the last three decades (1960-1990) especially, the importance of instream flows has
become, recognized more widely as essential to maintain and restore values and uses
of water for fish, wildlife, ecological processes, and other environmental, recreational
and aesthetic purposes. By the mid-1980's, at least 20 states provided legislative rec-
ognition of instream flows for fish and other aquatic resources. Nine of these were
western states, where the concept and initiative for maintaining flows for these purposes
had origin under western appropriation water law, starting in 1915 in Washington State.
Although needs for assuring instream flows began to be recognized about three-
quarters, of a century ago, it was not until the mid-1970's that methods were developed
to assess, and understand the effects of flow changes on instream values and uses. While
substantial progress has been made in perfecting those methods, additional efforts are
needed to adapt them for use in more geographic areas, including the eastern United
States with its riparian water law.
In the last 15 years (1974-1989), procedures for evaluating impacts of streamflow
changes on instream uses have advanced considerably. Most preliminary planning
methods involve (1) hydrologic characteristics used to develop minimum flow recom-
mendations based on streamflow statistics, and (2) hydraulic features required to for-
mulate recommendations to provide streamflow dependent habitats. Methods developed
in states to establish minimum flow standards to guide allocation of water withdrawals
from streams and to protect water quality usually are based on analyses of historic
annual, seasonal and/or daily streamflow records. Impact assessments of proposed water-
development projects focus on evaluating changes in fish habitats (e.g., quantity of
riffles, and quality of spawning areas) associated with different increments of stream-
flow.
All of these useful methods have become increasingly important in responding to
growing public concerns over ensuring habitats for wild living resources and to new
legal demands for perpetuating habitats and values associated with stream channels
and adjacent riparian areas, including wetlands. For example, implementation of the
comprehensive federal Endangered Species Act (1973) requires reexamination of water
allocations made historically. Joint federal/ state agreements are being established, such
Rivers Volume 1, Number 1 Pages 1-2 1 IN