Dataset

Database Code

HF004

Title

Stream discharge in gaged watersheds at the HJ Andrews Experimental Forest, 1949 to present

Abstract

Streamflow from selected small watersheds has been continuously monitored at the HJ Andrews Experimental Forest since November 1952. The objectives of this research and monitoring include: (1) evaluate long-term changes in hydrology associated with various forest management treatments, notably clearcut logging, selective logging, and burning of predominantly Douglas-fir conifer forests; (2) characterize the hydrologic regimes and evaluate mechanisms influencing water availability from conifer forests; and (3) provide baseline data for affiliated precipitation and stream water chemistry and sediment transport studies. In addition to stage heights and discharge, data on stream chemistry, stream and air temperature, specific conductivity are collected at the stream gages. Models have also been extensively calibrated with these data to characterize the hydrologic regimes of forests at different elevations and following forest management. Many other studies within the watersheds also use these hydrology data. The original design for the first- and second-order small watersheds used a paired watershed technique to evaluate changes in streamflow following forest management and harvest in conifer forests. A reference watershed remained unharvested within each set (Andrews WS 1, 2, 3; WS 6, 7, 8; and WS 9, 10). Watershed details and treatments are described at https://andrewsforest.oregonstate.edu/research/infrastructure/watersheds and in the 'Gaged watershed description' PDF in Related Materials/Files. Mack Creek is a third-order watershed where the reference was upstream of the harvested section. The fifth-order Lookout Creek has a gage maintained by US Geological Survey. Early discharge data from Lookout Creek gage, including for the period when USFS maintained the gage, are available here. Measurements of stream stage heights are recorded in feet and streamflow data are available in units of cubic feet per second (cfs). Discharge is calculated using rating curves that have been developed over time. Rating curves and flow calculations are also available in PDF in Related Materials/Files. Data are currently recorded at five-minute intervals. Interpolations of older data originally collected at longer-time steps are available in entity 5 below. Raw instantaneous streamflow data in cubic feet per second (cfs) and mean flow at fine temporal intervals are available. Rating curves for fixed trapezoidal flumes are maintained for all small watersheds except Lookout Creek and allow calculation of mean and total flow. The USGS-maintained Lookout Creek relies on annual rating table development to reflect changes in the open channel for instantaneous flow calculation. Entity 1 includes a reconstructed history of USGS Lookout Creek hourly data beginning in 1950 and more recently 30 and 15 minute interval data. Calculated mean cfs and total flow for each watershed are available at daily (Entity 2), monthly (Entity 3), annual (Entity 4), and stream sampling (Entity 6) time intervals. An interactive program, FLOW (Entity 5), allows the user to download instantaneous, mean and total flow at requested time periods (e.g., 5 minute, 15 minute, hourly) for all watersheds except for Lookout Creek.

Keywords

hydrology; silviculture; floods; disturbance; hydrologic processes; stream discharge; streamflow; long term monitoring; timber harvest; water; runoff; forest ecosystems; watersheds; streams; radio telemetry; experimental forests; long term studies; disturbance

Date begin

1949-10-01

Date end

2024-10-01

Principal Investigator

Sherri L. Johnson

Entities

1. Corrected instantaneous stage height with flow calculations
2. Daily streamflow summaries
3. Monthly streamflow summaries
4. Annual streamflow summaries by wateryear (October 1 - September 30)
5. Flow summaries for sediment and nutrient sampling periods
6. Discharge data calculated from discontinued rating curves (5 minute frequency data)

1. Corrected instantaneous stage height with flow calculations - Attribute list

2. Daily streamflow summaries - Attribute list

3. Monthly streamflow summaries - Attribute list

4. Annual streamflow summaries by wateryear (October 1 - September 30) - Attribute list

5. Flow summaries for sediment and nutrient sampling periods - Attribute list

6. Discharge data calculated from discontinued rating curves (5 minute frequency data) - Attribute list

Attribute definitions

BEGIN_DATETIME

Beginning date and time of proportional sampling period

DATE

Date

DATE_TIME

Date and time (PST) of stage height measurement

END_DATETIME

Ending date and time of proportional sampling period

EQN_SET_CODE

Equation set code describes the rating equation set and version used to calculate streamflow

ESTCODE

Estimate code

ESTDAYS

Number of days estimated in the summary period

EVENT_CODE

Indicates that a comment exists independently for this date and time, and is typically the installation or removal of a v-notch or other change in rating curves used, or a site maintenance visit

FORMAT

Entity number

INST_Q

Instantaneous flow as cubic feet per second (cfs)

INST_Q_AREA

Instantaneous flow as cubic feet per second per square mile (cfsm)

INTERVAL

Time interval in minutes (length of time since previous stage value)

MAX_Q

Maximum cubic feet per second (cfs) for this date (entity 2) or month (entity 3) or year (entity 4)

MEAN_Q

Mean flow as cubic feet per second (cfs) for the preceding time interval (entity 1, 5) or this date (entity 2) or month (entity 3) or year (entity 4)

MEAN_Q_AREA

Mean flow as cubic feet per second per square mile (cfsm) for the preceding time interval (entity 1, 5) or this date (entity 2) or month (entity 3) or year (entity 4)

MIN_Q

Minimum cubic feet per second (cfs) for this date (entity 2) or month (entity 3) or year (entity 4)

MONTH

Calendar month

SITECODE

Site code

STAGE

Stage height

STCODE

Study code

TOTAL_DAYS

Total days of non-missing record included in the summary period

TOTAL_Q_AREA

Total flow as inches of water (over the watershed area) for this date (entity 2) or month (entity 3) or year (entity 4)

TOTAL_Q_INT

Total flow as inches of water (over the watershed area) for the preceding time interval

TOTAL_Q_SMPL

Total flow as inches of water during proportional sampling period (over the watershed area)

WATERYEAR

Wateryear: October 1 - September 30

YEAR

Calendar year

Enumerated domains

Enumerated domain for attribute: STCODE

Enumerated domain for attribute: SITECODE

Enumerated domain for attribute: EQN_SET_CODE

Enumerated domain for attribute: ESTCODE

Enumerated domain for attribute: EVENT_CODE