A description of the scope of work follows. Dr. Lynn Leonard at the
University of North Carolina, Wilmington is conducting the investigation.
For more information and data, see
Description of Work
Monitoring Effects of a Potential Increased
Tidal Range in the Cape Fear River Ecosystem
Due to Deepening Wilmington Harbor, North
Year 1: 7 August 1, 2000 – July 31, 2001
The contractor will be responsible for
performing all the sample collection and analysis, monitoring, routine
equipment maintenance, and data management associated with the activities indicated
a. Monitoring Associated with Data
Collection Platforms (DCP):
Under a separate contract, DCP’s have been installed at the eleven
(11) station locations indicated in the March 1999 CZR Report (P1, P2, P3, P6,
P7, P8, P9, P11, P12, P13, & P14). Instruments installed on each DCP were
a water level recorder (Unidata Water Level Monitor) and a programmable data
logger (Unidata Star Logger). The water
level recorder is tied into the logger along with probes for salinity (from
conductivity), and temperature. The
primary water level sensor is a shaft-encoder instrument installed in a
stilling well. The water level sensor
was leveled directly to local benchmarks that provide absolute measurements
referenced to local water level datums.
These sensors have an accuracy of 1/100 ft over a 10-foot water level
range. Data will be retrieved from the
logger via a cellular communication system every 1-2 weeks. The entire package is contained in a
watertight housing and powered by a 12-volt battery, recharged with solar
addition, a Unidata Star Logger with probes for
conductivity and temperature was installed at the existing NOAA tide gauge at
the Corps of Engineer Yard. No
telemetry is available for this site; therefore, the data must be manually
downloaded every 1-2 weeks.
level monitoring will follow the sampling protocol established by the NOS
(1998). The data loggers are programmed
to collect measurements at 6-minute intervals with each measurement consisting
of a set of 181 1-second-interval water level samples centered on each tenth of
an hour. The mean of 181 are reported
along with the maximum and minimum over the measurement period. The reported measurements have 0.01-foot
resolution and are stored in the system memory of the data logger. To ensure quality data, it will be necessary
to conduct monthly maintenance of DCP’s.
Each DCP and its sensors will be cleaned and visually inspected for
National Oceanic and Atmospheric Administration (NOAA) routines will be used to
calculate tidal harmonics. Statistical
evaluation of computed amplitudes and phases will be conducted at a confidence
level of alpha=0.05. Tidal phase
differences between stations will be used to establish a baseline tidal lag
time over the length of the study area.
Mean amplitudes and harmonic amplitudes will be determined for each
station. These data will establish
amplitude differences currently existing between sites. Pre-project water level data will further be
used to evaluate maximum background fluctuations.
conductivity and temperature measurements will be collected by hand at the
surface and at the maximum depth of the stilling basin once per month at each
station. These measurements will be
used to assess variability in conductivity and temperature in the water column
and to verify instrument calibrations.
Conductivity sensors will be calibrated each day before and after water
column measurements are made.
monitoring period for this work will be from contract award through July 31,
b. Benthic Invertebrates: At
Eight (8) of the stations indicated in the March 1999 CZR Report [P2, P3a&b
(on both sides of Town Creek combined as one station), P6, P7, P8, P11, P12,
& P13], benthic invertebrates will be sampled at two subsites (high
intertidal and low intertidal) along each of two transects running
perpendicular to the river/creek's edge.
Three benthic cores will be taken at each of these four locations per
station (two transects X two subsites).
at all stations for benthos will be done in June 2001. Samples will be taken with a 0.007 m2
area by 10 cm deep corer. The contents
will then be sieved through a 0.5 mm screen, fixed in 10% formalin, and
subsequently transferred to 70 percent isopropanol. Sorting will be required to separate fauna from root matrices and
detrital debris before enumeration and identifications is done. Then all benthic fauna will be identified to
the species or genus level where possible.
Benthic fauna will also be classified into functional guilds based on
living position and life history type (Fauchald and Jumars 1979, Posey 1990),
including classifications considering dispersal mode and salinity tolerances.
a separate contract, sampling was also performed for benthic invertebrates in
June 2000 at the same 8 locations and using the same sampling procedure. These previous samples were just sieved
through a 0.5 mm screen, fixed in 10% formalin, and subsequently transferred to
70 percent isopropanol. These previous samples will also be sorted and
identified using the same methods indicated in the previous paragraph.
c. Epibenthic Fish and Decapods:
Monitoring of epibenthic fish and decapods will be conducted at the same
eight (8) stations indicated for monitoring for benthic invertebrates [(P2, P3
on both sides of Town Creek combined as one station), P6, P7, P8, P11, P12,
& P13]. Monitoring will be done
twice per year, once during September-October 2000 and once during March-April
2001. At each sampling station, epibenthic
fish and decapod use of wetland habitats will be monitored at three subsites
along each of two transects running perpendicular to the river's edge (2
transects x 3 subsites=6 subsites per station). The three subsites per transect will correspond to shallow
subtidal, mid-intertidal, and high intertidal elevations, and exact locations
will be determined from site characteristics, elevation surveys, and
coordination with other monitoring efforts.
Juvenile fish and decapod abundances will be monitored through a
combination of Breder and drop trap sampling.
Both sampling methods have been used in other studies of wetland fish
and decapod use in the Cape Fear region (Townsend 1991; Griffitt, Posey, and
Both Breder and drop trap sampling are
conducted at high tide when the area is covered by water. Five Breder traps will be set simultaneously
at each subsite on each sampling date for a total of 30 per site. The traps are constructed of clear acrylic,
31 cm long x 15 cm wide x 16 cm high, with clear acrylic leader wings. Traps are placed facing downstream of
prevailing currents with at least 1 m between traps. The traps will be left in place for 1.5 hours.
Nine drop samples will be conducted at the
shallow subtidal subsite on each sampling date for a total of 18 per site. The drop traps are one meter aluminum
squares that are deployed by hand and all fish and decapods removed with a
All fauna will be counted, measured, and
identified to the species or genus level where possible.
d. Porewater Salinity, Sulfate and
Methane: At the nine (9) belt transects indicated in
the March 1999 CZR Report (P3 on only one side of the Town Creek, P6, P7, P8,
P9, P11, P12, P13, & P14), sediment pore water samples for chloride,
sulfate, and methane determination will be collected using a Hesslein‑type
peeper (Hesslein 1976). The peepers are
deployed in the substrate for 1-2 weeks while the concentrations of the
analytes in the peeper chambers water equilibrates with the surrounding
porewater. The concentration of all
parameters are determined after removing samples from peeper cells with a
syringe equipped with a needle. Sulfate
and chloride concentrations are determined with an ion chromatograph (Hoehler
et al. 1994). Salinity is calculated
from the chloride concentrations of the equilbrated peeper chamber water. Sulfate reduction in indicated by a
departure from seawater ratios of chloride and sulfate. Samples for porewater methane analysis are
prepared by extraction of porewater methane into an inert helium headspace
within a gas-tight syringe. The
headspace gas is then injected into a gas chromatograph equipped with a flame
ionization detector (Kelly et al. 1995) for quantitative determination of
methane concentration. The presence of elevated
methane concentrations indicates that sulfate concentrations are too low for
sulfate reduction to occur and that the sediment has not been recently
influenced by salt water intrusion.
One peeper is located at each of six
substations per transect with the substations generally equally spaced along
the long axis of each transect. Where
feasible, the peepers will be located in the area with sensitive vascular
herbaceous vegetation as described in paragraph “f” below. Each substation is accessed by boardwalks
that were installed under a separate contract.
The porewater sampling will be conducted during each of two sampling
periods: December -February 2000/2001
and June-August 2001. One station will
be monitored monthly to determine the maximum-minimum pattern.
determine pore water sulfate concentrations, a small amount of concentrated
acid will be added and samples shaken to remove any volatile sulfide compounds
that otherwise would be converted to sulfate under oxic conditions. Sulfate concentrations are stable under oxic
conditions and can be stored in serum vials until analysis. Sulfate concentrations will be determined
with an ion chromatograph following the method of Hoehler et al. (1994).
methane concentrations are also derived from water extracted from peeper cells
into airtight glass syringes equipped with a three-way stopcock and a
needle. Contact with air is minimized
to prevent oxidation of methane.
Samples will be transported back to the laboratory on ice. A known quantity of air will be drawn into
the syringe and the sample shaken vigorously to extract the highly insoluble
methane gas into the headspace of the syringe.
The headspace will then be injected into a gas chromatograph equipped
with a flame ionization detector to determine methane concentration. The porewater methane concentration will be
calculated from the amount of porewater and headspace in the syringe following
Kelley et al. (1995).
concentrations will be reported to the nearest tenth of a part per thousand,
and methane and sulfate concentrations will be reported to the nearest 100
micromoles and 2 micromoles, respectively.
e. Belt Transects Surface Water Levels and
Salinity: At the nine (9) belt transects indicated in
the March 1999 CZR Report (P3 on only one side of the Town Creek, P6, P7, P8,
P9, P11, P12, P13, & P14), water level (RDS WL20s and WL40s) and salinity (Unidata Star Logger with conductivity
probe) data will be collected.
One WL20s or 40s and one salinity probes will be located at each of six
substations per transect with the substations generally equally spaced along
the long axis of each transect. Each
substation is accessed by boardwalks that were installed under a separate
contract. These are the same
substations indicated in paragraph “d” above.
The equipment will be deployed over fortnightly sampling periods at each
transect during each of two sampling periods:
August-December 2000 and February-June 2001. Fortnightly sampling will account for spring/neap variability. One-minute averages of water level and
salinity (conductivity) will be recorded once every 6 minutes during
inundation. The data will be manually
download every 1-2 weeks.
Data will need to be recorded to the nearest
hundredth (1/100) of a foot for water level measurements and nearest tenth of a
part per thousand for salinity.
f. Vegetation: At
the nine (9) belt transects indicated in the March 1999 CZR Report (P3 on only
one side of the Town Creek, P6, P7, P8, P9, P11, P12, P13, & P14), major
plant communities or cover types will be described along with approximate
widths (i.e. the same procedure as in the March 1999 CZR Report). In addition within each belt transect, areas
of sensitive vascular herbaceous vegetation will have their perimeter mapped
(at an appropriate scale) and area determined using GPS technology with
sub-meter accuracy. Also for sensitive
vascular herbaceous vegetation, percent cover will be estimated within these
perimeters. Sensitive vascular
herbaceous vegetation is defined as non-woody vegetation intolerant to changes
in soil chemistry, inundation regime, or salinity that may be caused by the
deepening project. This work will be
performed in June-July of 2001.
Assurance and Control: Quality Assurance and Control will be
performed in accordance with Section 2.10 of the May CZR 1998 Report.
Collection and Data Analysis Protocols: Manuals will be
prepared detailing data collection and data analysis monitoring protocols for
paragraphs “a-g” above. The manuals
will contain sufficient information so that an independent party could
duplicate the monitoring efforts.
and Vertical Control. Horizontal and vertical controls have been
established at all locations indicated below.
The contractor will not alter any of these controls or structures
associated with these controls indicated below without first obtaining written
consent from the contracting officer.
If any of these control are altered by the contractor, they will be
reestablished by the contractor at no cost to the government.
water level sensors on the DCP’s,
and temperature sensors at each DCP location and at the Corps of Engineer Yard,
each of the 9 belt transects:
3) one fix on the top of a solid steel rod >
1.0 cm in diameter and at least 2.5 meters long driven at least 2 meters
vertically into the substrate, and
4) all belt transect water level monitoring
Monthly and Annual Reports:
a. Monthly Status Report: By the fifth working day of each month, a
written letter report is required for the previous month’s activities. This report will summarize sampling
activities, preliminary results, and important observations. These status reports shall also be used to
discuss potential problems and solutions related to contract performance or
conditions which may affect performance.
Monthly status reports must accompany requests for partial payment.
b. Annual Project Report: Upon completion of all work tasks under the
contract, the Contractor shall submit a draft report for review. The report and findings shall be objective
and fully substantiated by documentation.
The report shall follow the format required by reputable scientific
periodicals, including abstract, summary, introduction, methods, results,
discussion, conclusions and recommendations, references, and appendices. The appendices will contain tabulations of
all physical, biological, and statistical data and a list of all participating
technical staff and their respective responsibilities on the project. The report shall contain appropriate summary
tables and figures. In addition, the
report must include:
(1) equipment maintenance and data
collection procedures, equipment replacement and malfunctions, and problems
with lost or questionable data;
(2) description of monitoring
methodology, results and any problems;
(3) discussion of the results including
habitat value and apparent difference in sites from downstream to upstream.
Text material shall be typed or printed with
a letter quality printer (dot matrix printing is not acceptable) on 8-1/2"
by 11" bond paper with 1-1/2" margins on the left for binding. All pages must be consecutively numbered. Drawings or plates bound in the report shall
be no larger than 11" by 17" and shall include a graphic bar scale
for control during reduction or enlargement.
Additional larger maps or drawings shall be provided on standard
30" by 42" sheets, unless the Contracting Officer and the Contractor
agree otherwise. The Contracting Officer will provide written comments on the
accepted draft report. The Contractor
will revise the report in accordance with these comments and, then, submit the
report as final.
Ten copies of the draft report
including the Data Collection and Data Analysis Protocols must be submitted by
November 1, 2001, to the U.S. Army Corps of Engineers, Wilmington District, for
review. A draft report requiring
extensive proofreading or incomplete draft reports will be returned to the
Contractor as unacceptable. Twenty-five copies of the final report must be
submitted to the Corps within 30 working days after the date the Corps provides
comments on the draft to the contractor.
cover of the project report must bear the title "Monitoring Effects of a
Potential Increased Tidal Range in the Cape Fear River Ecosystem Due to
Deepening Wilmington Harbor, North Carolina, Year 1: August 1, 2000 – July 31, 2001”, "Prepared for the
Wilmington District, US Army Corps of Engineers.", and Contract
Number. In addition, the title page
shall bear an inscription stating Project Manager: (Name). If the document has been prepared by someone
other than the Project Manager, this inscription will, instead, state Prepared
Under the Supervision of (Name), Project Manager. The original copy of the final report shall be signed by the
Contractor shall provide one copy of the entire final report text, including
all tables, charts, and appendices, on
IBM Personal Computer readable floppy disks or compact disk. The enclosure indicates the format required
for all electronic files delivered to the District.
CZR, Incorporated. 1999. Location of
Permanent Stations, Background Stations, and Substations for Monitoring
Potential Effects of Increased Tidal Range on the Cape Fear River Ecosystem Due
to Deepening Wilmington Harbor, North Carolina. Prepared for U.S. Army Corps of Engineers, Wilmington District,
Wilmington, North Carolina. March 1999.
CZR, Incorporated. 1998. A Monitoring Plan
to Determine Potential Effects of Increased Tidal Range on the Cape Fear River
Ecosystem Due to Deepening Wilmington Harbor, North Carolina. Prepared for U.S. Army Corps of Engineers,
Wilmington District. May 1998.
Fauchald, K. and P.A. Jumars. 1979. The diet
of worms: a study of polychaete feeding guilds. Oceanography and Marine Biology
Annual Reviews 17:477-489.
Griffitt, B.J, M.H. Posey, and T.D.
Alphin. 1999. Effects of edge fragmentation on oyster reef utilization by
transient nekton. J. of Elisha Mitchell
Scientific Society 115:98-103
Hesslein, R.H. 1976. An in situ sampler for
close interval pore water studies.
Hoehler, T.M., M.J. Alperin, D.B. Albert and
C.S. Martens. 1994. Field and laboratory studies of methane
oxidation in an anoxic marine sediment: Evidence for a methanogen‑sulfate
reducer consortium. Global
Biogeochemical Cycles 8:451‑463.
Kelley, C.A., C.S. Marten, and W. Ussler
III. 1995. Methane dynamics across a tidally flooded riverbank margin. Limnology and Oceanography 40:1112‑1129.
National Ocean Survey. 1998. The New Water
Level Measuring System. Oceanographic Products and Services Division. http://www.co-ops.nos.noaa.gov/levlhow3.html.
1990. Functional approaches to
soft-substrate communities: How useful
are they? Reviews in Aquatic Science
Sargent, W.B. and P.R. Carlson, Jr. 1987. Utility of Breder
traps for sampling mangrove and high marsh fish assemblages. Proceedings from the Fourteenth Annual
Conference on Wetland Restoration and Creation. PP 194-205.
Townsend, E. C. 1991. Depth Distribution
of grass shrimp (Palaemonetes pugio) in Two Contrasting Tidal
Creeks in North Carolina and Maryland.
MS Thesis, University of North Carolina at Wilmington.
Wilmington District Corps of Engineers,
Geospatial Data and Systems Standards
The following paragraphs represent the
format for electronic files being delivered as part of any contract. These paragraphs do not specify content or
what the electronic files should contain.
The content or data represented should be specified in the basic Scope
1. Specifications For Digital Data. Any maps, drawings, figures, sketches,
databases, spreadsheets, or text files prepared under the terms of this
contract shall be provided in both hard copy and digital form, unless otherwise
specified in the Scope of Work. The
hard copy deliverables shall be defined in the body of the basic Scope of Work.
2. Text, Spreadsheet, and Database Files: The U.S. Army Corps of Engineers, Wilmington
District standard computing software is Microsoft Office. Reports and other text documents shall be
provided in Microsoft Word 97 format.
Spreadsheet files shall be provided in Microsoft Excel format. Databases shall be provided in Microsoft
Access format, unless otherwise specified in the basic Scope of Work. Prior to database development, the
contractor shall provide the Government with a Technical Approach Document for
approval which describes the contractor's technical approach to designing and
developing the database. All text,
spreadsheet, and database files shall be delivered on 3.5 inch, high density
diskettes, 100mb ZIP Disks, or compact disk read-only memory (CD-ROM) with
Mapping and Data Standards: The U.S.
Army Corps of Engineers, Wilmington District utilizes Microstation for Computer
Assisted Drafting and Design CADD.
Geographic Information System (GIS) Data Delivery Format:
Digital geographic maps and the related digital information shall be
developed using double precision and delivered in uncompressed ARC/INFO export
file format (.e00) using ARC/INFO Release 7.2 or higher. ARC/INFO is a geographic information system
software application produced by the Environmental Systems Research Institute
of Redlands, California, and is the software used by U.S. Army Corps of
Engineers, Wilmington District.
b. Digital geographic maps and the related
digital information shall be usable on a IBM compatible personal computer
system using the Windows NT 4.0 operating system. This data shall be provided on compact disk read-only memory
(CD-ROM) with ISO-9660 format. Digital
information may alternatively be delivered on 100mb ZIP Disks.
General Digital Standard for CADD and GIS Files
a. Geographic data shall be provided in feet
and projected into the North Carolina State Plane coordinate system. The maps shall use the GRS 1980 spheroid and
the North American Datum 1983 (WGS-84).
No offsets shall be used. Each
map layer or coverage shall have a projection file. Map or drawing scales will be determined by the Contracting
Officer's Representative for the contract.
Mapping accuracy for the agreed scales will conform to the American
Society for Photogrammetry and Remote Sensing (ASPRS), "Accuracy Standards
for Large-Scale Maps" and “Interim Accuracy Standards for Large-Scale
Maps” (ASPRS, 1991). Copies of the
ASPRS Accuracy Standards can be obtained by contacting:
American Society for Photogrammetry and
5410 Grosvenor Lane, Suite 210
Bethesda, MD 20814-2160
ASPRS accuracy standards can also be found
on the Internet at:
Geographic data must be provided in a form that does not require
translation, preprocessing, or postprocessing before being used in the U.S.
Army Corps of Engineer’s System.
However, the Contractor shall consult with the Government (specifically
the Geographic Information Systems Office) concerning the use of alternative
delivery formats such as MicroStation SE or higher to provide design drawings,
sketches, or figures. The Government
may approve the use of AutoCAD when it is determined that the format will not
compromise the spatial accuracy or structure of the delivered data and that the
data will easily integrate with the U.S. Army Corps of Engineers, Wilmington
District’s System. All digital files
provided in Microstation shall be in the same projection and use the same
coordinate system, datum, and units as stated above, and shall be provided on
3.5 inch, high density diskettes, 100mb Zip Disks, or CD-ROMs.
c. Geographic Data Structure: All geographic information shall be
developed in a structure consistent with the Spatial Data Standards (SDS),
Version 1.9, released in December 1999, or a higher version if available at the
time of this project. The Contractor
shall consult with the Government concerning modifications or additions to the
SDS. The Government may approve
modifications to the Standard if it is determined that SDS does not adequately
address subject data sets. Copies of
the SDS may be obtained by contacting:
Director, U.S. Army Engineer Waterways
Tri-Service CADD/GIS Technology Center
3909 Halls Ferry Road
Vicksburg, MS 39180-6199
Electronic copies of the Standards are also
available from the Tri-Service CADD/GIS
Technology Center's Internet homepage at URL
Geographic Data Documentation: For each digital file delivered
containing geographic information (regardless of format), the Contractor shall
provide documentation consistent with the "Content Standards for Digital
Geospatial Metadata, June 1998" published by the Federal Geographic Data
Committee. The documentation shall
include but is not limited to the following:
the name and description of the map layer or coverage, the source of the
data and any related data quality information such as accuracy and time period
of content, the type of data coverage (point, line, polygon, etc.), the field
names of all attribute data and a description of each field name, the
definition of all codes used in the data fields, the ranges of numeric fields
and the meaning of these numeric ranges, the creation date of the map layer and
the name of the person who created it.
A point of contact shall be provided to answer technical questions. A metadata generation software, called
Document.aml, is available from ESRI for use with ARC/INFO to help in the
production of the required metadata.
Copies of the FGDC metadata standard can be obtained by contacting:
c/o U.S. Geological Survey
590 National Center
Reston, Virginia 22092
FGDC metadata standards can also be found on
the Internet at:
Geographic Data Review: The
digital geographic maps, related data, and text documents shall be included for
review in the draft and final contract submittals. The reviews may include a visual demonstration of the geographic
data on the Windows NT computer system in the Environmental Resources Section
GIS Unit’s. Actual installation of the
digital data from the CD-ROM onto the computer will be conducted by GIS Unit
personnel. However, the Contractor
shall have a technical consultant available at each review to assist with any
digital data discrepancies. The data
will be analyzed for subject content and system compatibility. Review comments to data and text shall be
incorporated by the Contractor prior to approval of the final submittal.
Ownership: All digital files,
final hard-copy products, source data acquired for this project, and related
materials, including that furnished by the Government, shall become the
property of U.S. Army Corps of Engineers, Wilmington District and will not be
issued, distributed, or published by the Contractor.
Prepared by the Environmental Resources
Section GIS Team (910/251-4755)