Prospect Hill Hydrological Stations

Data

• hf070-01: station log
• hf070-02: manual measurements
• hf070-03: modeled daily 2005-2007
• hf070-04: modeled hourly 2005-2007
• hf070-05: daily
• hf070-06: 15-minute

Overview

• Lead: Emery Boose
• Investigators: Paul Barten, Elizabeth Colburn, Mark VanScoy, William Sobczak
• Contact: Emery Boose
• Start date: 2005-04-01
• End date: ongoing
• Location: Prospect Hill Tract (Harvard Forest)
• Latitude: +42.53 to +42.55
• Longitude: -72.20 to -72.17
• Elevation: 280 to 420 meters
• Taxa:
• Research topic: watershed
• Study type: long-term measurement
• LTER core area: inorganic nutrients, disturbance
• Keywords: hydrology, stream discharge, water budget, water temperature, wetland
• Release date: 2007
• EML version: knb-lter-hfr.70.9
• Revisions: data updated every 1-2 weeks
• Related links:
• Site Map
• Photos
• Fisher Meteorological Station (since 2001)
• Abstract:

  To better understand the critical role of headwater streams and wetlands in our forest ecosystem, long-term measurements were initiated in 2005 on two small watersheds in the Prospect Hill Tract of the Harvard Forest. On Nelson Brook, weirs were installed on outlet streams of an 11-ha spruce-hemlock wetland (watershed area = 44 ha). On Bigelow Brook, pipes were installed to measure flow above (watershed = 24 ha) and below (watershed = 65 ha) a 3-ha shrub-dominated beaver swamp. Weekly manual measurements were initiated in April 2005. Continuous automated measurements were initiated in December 2007. The gauged watersheds, though adjacent and comparable in size, differ significantly in topography, soils, wetlands, stream chemistry, stream biota, land-use history, and forest vegetation, and provide an extraordinary opportunity to study the impacts of these factors on small watershed hydrology and ecology. Future plans include development of a wireless network and cyberinfrastructure tools to integrate these data with ET (evapotranspiration) data from the eddy flux towers and meteorological data from the met station to provide near-real-time estimates of water budgets for these watersheds.

• Methods:

  Experimental Design

  See online map for locations of gages and watershed boundaries. Note that the two Nelson gages measure discharge from the same watershed (parallel outlets), while the Bigelow gages measure discharge from nested watersheds. Nelson Brook flows northwest to the Millers River and Connecticut River. Bigelow Brook flows southeast to the Swift River, Quabbin Reservoir, Chicopee River, and Connecticut River.

  Nelson Brook Big Weir (NB). 120-degree V-notch weir with rectangular spillway. V-notch height = 10 in (25.4 cm). Spillway width = 13 ft (3.96 m). Watershed area = 44 ha.

  Nelson Brook Little Weir (NL). 120-degree V-notch weir with rectangular spillway. V-notch height = 4 in (10.2 cm). Spillway width = 5 ft (1.52 m). Watershed area = 44 ha.

  Bigelow Brook Lower Pipe (BL). Corrugated polyethylene pipe with smooth interior. Diameter = 30 in (76.2 cm). Length = 16 ft (4.88 m). Slope = 0.01087. Manning coefficient = 0.012. Watershed area = 65 ha.

  Bigelow Brook Upper Pipe (BU). Corrugated polyethylene pipe with smooth interior. Diameter = 24 in (61.0 cm). Length = 10 ft (3.05 m). Slope = 0.01969. Manning coefficient = 0.012. Watershed area = 24 ha.

  Black Gum Swamp (BGS). Nelson Brook watershed. Wetland area = 11 ha.

  Beaver Swamp (BVS). Bigelow Brook watershed. Wetland area = 3 ha.

  Manual Measurements

  Water levels at weirs are measured with attached gages (relative to notch). Water levels inside pipes are measured with ruler and chalk 40 cm from downstream end. Water levels in BGS and BVS were originally measured in an existing well (relative to soil surface) and at an existing gage (relative to 3.28 feet), respectively. In fall 2008 new gages for automated measurements were installed at new locations in each wetland. Bigelow Lower Pipe was replaced on 16-Oct-2006. Before that date, the pipe was corrugated steel with a partial asphalt liner, diameter = 36 in (91.4 cm), length = 16 ft (4.88 m), slope = 0.01087, manning coefficient = 0.019.

  Modeled Discharge 2005-2007

  Discharge was estimated with a simple linear reservoir model using a 1-hour time step. Input variables include precipitation, base flow, and fraction of precipitation returned as event flow. The last two variables were estimated from manual measurements. Modeled discharge values are subject to change with improvements to the model.

  Automated Measurements

  Water level: Druck 1830 2.5 psig pressure transducers. Water temperature: Campbell 107 temperature probes. At weir sites, instruments are mounted on steel brackets attached to the weirs. At pipe sites, instruments are mounted in wells 30cm below the bottom of the stream channel and 1 m upstream from the pipe intake. At wetland sites, instruments are mounted on vertical pipe 60cm below average water level. At each site a permanent manual gage may be used to check instrument readings. Instruments are scanned every 10 seconds and 15-minute average values are retained. Date/Time values indicate the end of the observation period. All times are Eastern Standard Time.

  Data analysis

  Stream discharge is calculated from water level (stage) using standard flow equations. At pipe sites, water depth in the pipe is estimated from measured stage using empirical rating curves. Daily values are calculated from 15-minute measurements. Data are checked and posted with missing, questionable, or estimated values flagged, following methods of the LTER ClimDB project. A log of events affecting station measurements is also posted.

  Operational notes

  Gages are not heated. Ice is removed regularly in winter to ensure proper flow through the gages. At Nelson Little Weir, instruments may be removed in mid-winter to prevent ice damage, in which case discharge is estimated from measured flow at Nelson Big Weir.

• Use:

  This dataset is released to the public and may be freely downloaded. Please keep the designated Contact person informed of any plans to use the dataset. Consultation or collaboration with the original investigators is strongly encouraged. Publications and data products that make use of the dataset must include proper acknowledgement. For more information on LTER Network data access and use policies, please see: http://www.lternet.edu/data/netpolicy.html.

• Citation:

  Boose E. 2007. Prospect Hill Hydrological Stations. Harvard Forest Data Archive: HF070.

Detailed Metadata

hf070-01: station log

1. Date: date (YYYY-MM-DD)
2. Notes: notes on station maintenance, repairs, and other issues affecting measurements

hf070-02: manual measurements

1. Date: date (YYYY-MM-DD)
2. NB-time: Julian day and fraction of a day (DDD.dddd)
3. NB-stg: measured stage at Nelson Big Weir (centimeter )
4. NB-dis: calculated discharge at Nelson Big Weir (litersPerSecond )
5. NL-time: Julian day and fraction of a day (DDD.dddd)
6. NL-stg: measured stage at Nelson Little Weir (centimeter )
7. NL-dis: calculated discharge at Nelson Little Weir (litersPerSecond )
8. BL-time: Julian day and fraction of a day (DDD.dddd)
9. BL-stg: measured stage at Bigelow Lower Pipe (centimeter )
10. BL-dis: calculated discharge Bigelow Lower Pipe (litersPerSecond )
11. BU-time: Julian day and fraction of a day (DDD.dddd)
12. BU-stg: measured stage at Bigelow Upper Pipe (centimeter )
13. BU-dis: calculated discharge at Bigelow Upper Pipe (litersPerSecond )
14. BGS-time: Julian day and fraction of a day (DDD.dddd)
15. BGS-stg: measured stage at Black Gum Swamp (centimeter )
16. BVS-time: Julian day and fraction of a day (DDD.dddd)
17. BVS-stg: measured stage at Beaver Swamp (centimeter )

hf070-03: modeled daily 2005-2007

1. Date: date (YYYY-MM-DD)
2. Jul: Julian date (DDD)
3. Prec: precipitation measured at Fisher Met Station (millimeter )
4. NT-dis: modeled discharge at Nelson weirs (litersPerSecond )
5. BL-dis: modeled discharge at Bigelow Lower Pipe (litersPerSecond )
6. BU-dis: modeled discharge at Bigelow Upper Pipe (litersPerSecond )

hf070-04: modeled hourly 2005-2007

1. DateTime: date and time (YYYY-MM-DDThh:mm)
2. JD: Julian day and fraction of a day (DDD.dddd)
3. Prec: precipitation measured at Fisher Met Station (millimeter )
4. NT-dis: modeled discharge at Nelson weirs (litersPerSecond )
5. BL-dis: modeled discharge at Bigelow Lower Pipe (litersPerSecond )
6. BU-dis: modeled discharge at Bigelow Upper Pipe (litersPerSecond )

hf070-05: daily

1. Date: date (YYYY-MM-DD)
2. JD: Julian day (DDD)
3. NT-dis: total discharge from Nelson Weirs (litersPerSecond )
4. F-NT-dis: flag for NT-dis
   • E: Missing. Instrument not installed, instrument not working correctly, or measured value out of range.
   • M: Estimated. Value estimated from incomplete measurements or from other sources.
5. BL-dis: discharge from Bigelow Lower Pipe (litersPerSecond )
6. F-BL-dis: flag for BL-dis
   • M: Missing. Instrument not installed, instrument not working correctly, or measured value out of range.
   • E: Estimated. Value estimated from incomplete measurements or from other sources.
7. BU-dis: discharge from Bigelow Upper Pipe (litersPerSecond )
8. F-BU-dis: flag for BU-dis
   • M: Missing. Instrument not installed, instrument not working correctly, or measured value out of range.
   • E: Estimated. Value estimated from incomplete measurements or from other sources.
9. NB-wt: water temperature at Nelson Big Weir (celsius )
10. F-NB-wt: flag for NT-wt
    • M: Missing. Instrument not installed, instrument not working correctly, or measured value out of range.
    • E: Estimated. Value estimated from incomplete measurements or from other sources.
11. BL-wt: water temperature at Bigelow Lower Pipe (celsius )
12. F-BL-wt: flag for BL-wt
    • M: Missing. Instrument not installed, instrument not working correctly, or measured value out of range.
    • E: Estimated. Value estimated from incomplete measurements or from other sources.
13. BU-wt: water temperature at Bigelow Upper Pipe (celsius )
14. F-BU-wt: flag for BU-wt
    • M: Missing. Instrument not installed, instrument not working correctly, or measured value out of range.
    • E: Estimated. Value estimated from incomplete measurements or from other sources.

hf070-06: 15-minute

1. DateTime: date and time at end of sampling period (YYYY-MM-DDhh:mm)
2. JD: Julian day and fraction of a day (DDD.dddd)
3. NB-stg: stage at Nelson Big Weir (centimeter )
4. F-NB-stg: flag for NB-stg
   • M: Missing. Instrument not installed, instrument not working correctly, or measured value out of range.
   • E: Estimated. Value estimated from incomplete measurements or from other sources.
5. NL-stg: stage at Nelson Little Weir (centimeter )
6. F-NL-stg: flag for NL-stg
   • M: Missing. Instrument not installed, instrument not working correctly, or measured value out of range.
   • E: Estimated. Value estimated from incomplete measurements or from other sources.
7. BL-stg: stage at Bigelow Lower Pipe (centimeter )
8. F-BL-stg: flag for BL-stg
   • M: Missing. Instrument not installed, instrument not working correctly, or measured value out of range.
   • E: Estimated. Value estimated from incomplete measurements or from other sources.
9. BU-stg: stage at Bigelow Upper Pipe (centimeter )
10. F-BU-stg: flag for BU-stg
    • M: Missing. Instrument not installed, instrument not working correctly, or measured value out of range.
    • E: Estimated. Value estimated from incomplete measurements or from other sources.
11. BGS-stg: stage at Black Gum Swamp (centimeter )
12. F-BGS-stg: flag for BGS-stg
    • M: Missing. Instrument not installed, instrument not working correctly, or measured value out of range.
    • E: Estimated. Value estimated from incomplete measurements or from other sources.
13. BVS-stg: stage at Beaver Swamp (centimeter )
14. F-BVS-stg: flag for BVS-stg
    • M: Missing. Instrument not installed, instrument not working correctly, or measured value out of range.
    • E: Estimated. Value estimated from incomplete measurements or from other sources.
15. NB-dis: discharge at Nelson Big Weir (litersPerSecond )
16. F-NB-dis: flag for NB-dis
    • M: Missing. Instrument not installed, instrument not working correctly, or measured value out of range.
    • E: Estimated. Value estimated from incomplete measurements or from other sources.
17. NL-dis: discharge at Nelson Little Weir (litersPerSecond )
18. F-NL-dis: flag for NL-dis
    • M: Missing. Instrument not installed, instrument not working correctly, or measured value out of range.
    • E: Estimated. Value estimated from incomplete measurements or from other sources.
19. NT-dis: total discharge from Nelson Weirs (litersPerSecond )
20. F-NT-dis: flag for NT-dis
    • M: Missing. Instrument not installed, instrument not working correctly, or measured value out of range.
    • E: Estimated. Value estimated from incomplete measurements or from other sources.
21. BL-dis: discharge from Bigelow Lower Pipe (litersPerSecond )
22. F-BL-dis: flag for BL-dis
    • M: Missing. Instrument not installed, instrument not working correctly, or measured value out of range.
    • E: Estimated. Value estimated from incomplete measurements or from other sources.
23. BU-dis: discharge from Bigelow Upper Pipe (litersPerSecond )
24. F-BU-dis: flag for BU-dis
    • M: Missing. Instrument not installed, instrument not working correctly, or measured value out of range.
    • E: Estimated. Value estimated from incomplete measurements or from other sources.
25. NB-wt: water temperature at Nelson Big Weir (celsius )
26. F-NB-wt: flag for NB-wt
    • M: Missing. Instrument not installed, instrument not working correctly, or measured value out of range.
    • E: Estimated. Value estimated from incomplete measurements or from other sources.
27. NL-wt: water temperature at Nelson Little Weir (celsius )
28. F-NL-wt: flag for NL-wt
    • M: Missing. Instrument not installed, instrument not working correctly, or measured value out of range.
    • E: Estimated. Value estimated from incomplete measurements or from other sources.
29. BL-wt: water temperature at Bigelow Lower Pipe (celsius )
30. F-BL-wt: flag for BL-wt
    • M: Missing. Instrument not installed, instrument not working correctly, or measured value out of range.
    • E: Estimated. Value estimated from incomplete measurements or from other sources.
31. BU-wt: water temperature at Bigelow Upper Pipe (celsius )
32. F-BU-wt: flag for BU-wt
    • M: Missing. Instrument not installed, instrument not working correctly, or measured value out of range.
    • E: Estimated. Value estimated from incomplete measurements or from other sources.
33. BGS-wt: water temperature at Black Gum Swamp (celsius )
34. F-BGS-wt: flag for BGS-wt
    • M: Missing. Instrument not installed, instrument not working correctly, or measured value out of range.
    • E: Estimated. Value estimated from incomplete measurements or from other sources.
35. BVS-wt: water temperature at Beaver Swamp (celsius )
36. F-BVS-wt: flag for BVS-wt
    • M: Missing. Instrument not installed, instrument not working correctly, or measured value out of range.
    • E: Estimated. Value estimated from incomplete measurements or from other sources.