| Title: |
Water Yield Costs of Planting
Abandoned Land on the Baltimore Municipal Watershed
|
| Objective: |
1) To evaluate the cost to a municipality of reduced water
yield from reforesting abandoned land.
2) To quantify the hydrologic impacts of forest management techniques
applied during the development of planted stands. |
| Year Established: |
1958 |
| Year Completed: |
1993 |
| Site Description: |
Three experimental watersheds ranging in size from 22 acres
to 38 acres are located northwest of Baltimore near Finksburg
in Maryland's piedmont region of hilly topography. The area
is approximately 39 deg 27 min 29 sec N.Lat. and 76 deg 53 min
30 sec W.Long.. Deer Park Road cuts across the top of watershed
no. 1 near a power line tower. Percent of precipitation that
leaves the watersheds as surface streamflow is considerably
less than from small mountainous watersheds in the east, especially
in the dormant season.
Soils of the Manor series predominate on the watersheds and
range from silt loam and gravelly loams and are somewhat excessively
drained. Depth to bedrock is 6-20+feet. Soils have moderate
to high available moisture capacity and are highly susceptible
to erosion. Glenelg series are second in importance. Delanco
series (moderately well-drained) exist along the stream channels.
Watershed 1 & 2 were formerly open grassland reforested
in 1955-56 with loblolly and white pines.
Watershed 3 is a mixed hardwood stand.
|
| Statistical Design: |
3 watersheds 22 to 38 acres in area. Paired watershed analysis;
single watershed calibration. |
| Likelihood of Locating Study Areas: |
100% |
| Experimental Treatments: |
Watershed 1 treatments:
1) Reforestation: vegetation change from open to forest via
loblolly and white pine plantings during 1955-56.
2) Vegetation Removal: vegetation was cut in particular areas
according to the following schedule.
Years after
planting:
|
Treatment: |
|
10
|
Hardwood vegetation along the main and secondary channels
cut back from streams a distance of 30 to 125 feet. |
|
11
|
Mechanical removal of stumps. Cut area seeded with grass. |
|
12
|
Grass cover in riparian area mowed. |
|
13
|
Pine plantation thinned except for 10% of stand on upper
end of watershed. Every other row was removed, producing
165 cords of wood. Stand not opened up greatly due to
closeness to original planting.
Grass cover in riparian area mowed. |
|
14
|
Grass cover in riparian area mowed. |
|
15
|
Remainder of pine plantation thinned by removing every
other row.
Remaining hardwoods along the fringe of the riparian zone
were cut.
Grass cover in riparian area mowed. |
Watershed 2
was the control watershed - no treatments applied.
Watershed 3 contains a
stand of mixed hardwoods. Streamflow measurements terminated
in 1976. Portions of watershed 3 streamflow data are questionable
due to leakage around gaging station. No treatments were applied.
|
| Sampling Methods: |
Streamflow is measured by a 120 degree, v-notch weir.
Precipitation indices were made to predict water yield from
watershed if trees were not planted. Correlations were made
between predicted and measured streamflow to quantify the effects
of reforestation. Differences between the streamflow reductions
on the two watersheds were used as estimates of the treatment
effects on watershed 1. Streamflow relationships between control
and watershed 1 during a 5-year period (1958-1962) were used
to develop equations for predicting the streamflow of watershed
1 from the measured streamflow at watershed 2. After modifying
the vegetation cover, differences between predicted and measured
streamflow for watershed 1 were used to quantify vegetation
treatment effects on water yield. |
| Variables and Sampling Frequency: |
streamflow (CFS,CSM, inches)
air temperature(degrees F)
relative humidity (%)
precipitation in amount (inches) & intensity
streamwater temperature (degrees F)
streamwater turbidity (NTU): 1958 to 1993, instrument charts
changed weekly. Data are summarized by month and year. |
| QA/QC Practices: |
Supervisor checks instrument calibrations periodically and
spot checks compilation and summarization of data by statistical
assistant. Water balance calculations are also used. |
| Data Storage: |
paper (4 file cabinet drawers), streamflow readings on computer
tape. |
| Global Change Research Applications: |
Studies of Ecosystem Processes |
| Data Availability: |
1995 |
| Publications and Reports: |
E.S. Corbett & W. Spencer. 1975. Effects of management
practices on water quality and quantity: Baltimore MD. In: Proceeding,
West Virginia municipal watershed management Symposium. 1973
September 11-12. Gen. Tech. Rpt. NE-13. Upper Darby, PA: U.S.
Department of Agriculture, Forest Service, Northeastern Forest
Experiment Station. 25-31.
Corbett, E.S.; Lynch, J.A. 1985. Management of streamside
zones on municipal watersheds. In: Riparian ecosystems and
their management: reconciling conflicting uses. Gen. Tech.
Rep. RM-120. Portland, OR: U.S. Department of Agriculture,
Forest Service, Northeastern Forest Experiment Station. 187-190.
|
| Contact: |
Richard Birdsey, USDA Forest Service, 11 Campus Boulevard,
Suite 200, Newtown Square, PA 19073. (610) 557-4091. |
| Cooperation: |
Bureau of Water Supply, City of Baltimore, MD. |
