Effects of forest practices on peak flows and consequent channel response : a state-of-the-science report for western Oregon and Washington / Gordon E. Grant [and others].

Format:

Book

Government document

Contributor:

Grant, Gordon, 1953-

Pacific Northwest Research Station (Portland, Or.)

Series:

General technical report PNW ; 760.

General technical report PNW ; 760

Language:

English

Subjects (All):

Forest hydrology--Oregon, Western.

Forest hydrology.

Forest hydrology--Washington (State), Western.

Logging--Environmental aspects--Oregon, Western.

Logging.

Forest influences--Oregon, Western.

Forest influences.

Forest influences--Washington (State), Western.

Logging--Environmental aspects--Washington (State), Western.

Watershed hydrology--Oregon, Western.

Watershed hydrology.

Watershed hydrology--Washington (State), Western.

Logging--Environmental aspects.

Western Oregon.

Western Washington (State).

Physical Description:

1 online resource (iv, 76 pages)

Place of Publication:

[Portland, Or.] : U.S. Dept. of Agriculture, Forest Service, Pacific Northwest Research Station, [2008]

Summary:

This is a state-of-the-science synthesis of the effects of forest harvest activities on peak flows and channel morphology in the Pacific Northwest, with a specific focus on western Oregon and Washington. We develop a database of relevant studies reporting peak flow data across rain-, transient-, and snow-dominated hydrologic zones, and provide a quantitative comparison of changes in peak flow across both a range of flows and forest practices. Increases in peak flows generally diminish with decreasing intensity of percentage of watershed harvested and lengthening recurrence intervals of flow. Watersheds located in the rain-dominated zone appear to be less sensitive to peak flow changes than those in the transient snow zone; insufficient data limit interpretations for the snow zone. Where present, peak flow effects on channel morphology should be confined to stream reaches where channel gradients are less than approximately 0.02 and streambeds are composed of gravel and finer material. We provide guidance as to how managers might evaluate the potential risk of peak flow increases based on factors such as presence of roads, watershed drainage efficiency, and specific management treatments employed. The magnitude of effects of forest harvest on peak flows in the Pacific Northwest, as represented by the data reported here, are relatively minor in comparison to other anthropogenic changes to streams and watersheds.

Contents:

Historical changes in management practices

Influences on peak flows

Paired watershed studies

Management treatments

Scaling hydrologic processes and effects

Peak flow data set compilation and analysis

Peak flow changes at the site scale

Analysis of peak flow increases in larger basins

Channel response to potential peak flow increases

Management implications.

Notes:

Title from title screen (viewed December 2, 2008).

"May 2008."

Includes bibliographical references (pages 48-64).

Electronic reproduction. [Place of publication not identified]: HathiTrust Digital Library. 2023.

Other Format:

Effects of forest practices on peak flows and consequent channel response

OCLC:

257637195

Access Restriction:

Use copy Restrictions unspecified