ANNUAL REPORT FOR 2006
Roanoke Island Mitigation Site
Dare County
Project No. 8.1052501
TIP No. K-4003
Prepared By:
Natural Environment Unit & Roadside Environmental Unit
North Carolina Department of Transportation
February 2007
TABLE OF CONTENTS
SUMMARY ..................................................................................................................... 1
1.0 INTRODUCTION.................................................................................................. 2
1.1 Project Description..................................................................................... 2
1.2 Purpose ..................................................................................................... 2
1.3 Project History ........................................................................................... 4
2.0 HYDROLOGY....................................................................................................... 4
2.1 Success Criteria......................................................................................... 4
2.2 Hydrologic Description............................................................................... 5
2.3 Results of Hydrologic Monitoring ............................................................... 5
2.3.1 Site Data ......................................................................................... 5
2.3.2 Climatic Data................................................................................. 11
2.4 Conclusions ............................................................................................. 11
3.0 VEGETATION: ROANOKE ISLAND VISITOR CENTER MITIGATION SITE.... 13
3.1 Success Criteria....................................................................................... 13
3.2 Description of Species ............................................................................. 13
3.3 Results of Vegetation Monitoring ............................................................. 13
3.4 Conclusions ............................................................................................. 13
4.0 OVERALL CONCLUSIONS AND RECOMMENDATIONS ................................. 14
LIST OF FIGURES
Figure 1. Site Location Map...................................................................................... 3
Figure 2. Gauge Location Map-North Tract .............................................................. 6
Figure 3. Gauge Location Map-South Tract.............................................................. 7
Figure 4 . Hydrologic Monitoring Results-North Tract ................................................ 9
Figure 5 . Hydrologic Monitoring Results-South Tract.............................................. 10
Figure 6. 30-70 Graph............................................................................................. 12
LIST OF TABLES
Table 1. Hydrologic Monitoring Results ................................................................... 8
APPENDICES
APPENDIX A - GAUGE DATA GRAPHS
APPENDIX B - SITE PHOTOGRAPHS, PHOTO AND VEGETATION PLOT
LOCATIONS, MECHANIZED CLEARING PHOTOGRAPHS,
MECHANIZED CLEARING IMPACT AREA
1
SUMMARY
The following report summarizes the monitoring activities that have occurred in the past
year at the Roanoke Island Mitigation Site. The site was constructed to serve as
mitigation for the Roanoke Island Visitor Center/ Rest Area; approximately 1.77 acres of
impacts are mitigated for onsite and the remaining 1.36 acres of preservation were
debited from the Mashoes Road Mitigation Site. The Roanoke Island Site was
constructed in 2002 and this report details the fifth year of hydrology monitoring and first
year of vegetation monitoring following construction.
There are three gauges located in the north tract with two gauges in the constructed
area and one gauge in the reference area. There are eight gauges located in the south
tract with four gauges in the constructed area and four corresponding gauges in the
reference area. For the three north tract gauges, only one of the gauges met the 20%
saturation period for it’s respective reference gauge. For the eight south tract gauges,
two of the gauges met the 20% saturation period for their respective reference gauges.
The two gauges that failed, would have met the 20% saturation period for it’s
corresponding reference gauge had it not been for gauge malfunctions.
Data from the fifth year of hydrologic monitoring indicates that all eleven monitoring
gauges demonstrated saturation within 12 inches of the surface for at least 12.5% of the
growing season. Gauge RIST-7 (ref) was moved to a more suitable location based on
similar elevation in August 2005, and met saturation within 12 inches of the surface for
57.4% of the growing season.
This site was replanted with bareroot seedlings in March 2006. Due to high soluble salt
levels at the site, the hardwood vegetation is surviving in very low numbers. The
preservation areas that were inadvertently cleared during construction of the site in
2002 were replanted. Photo documentation of the mechanized clearing areas will
continue to be provided to show the progression of the area returning to its original
state.
NCDOT will continue to monitor vegetation and hydrology at the Roanoke Island
Mitigation Site.
2
1.0 INTRODUCTION
1.1 Project Description
The Roanoke Island Site serves as onsite mitigation for the Roanoke Island Visitor
Center/Rest Area, located adjacent to the new US 64-264 Manteo Bypass. The site is
divided into two tracts; the “south” tract is on the same property as the Visitor Center
and the “north” tract is located approximately 600 feet north of the Visitor Center (Figure
1). The mitigation is associated with Project 8.1052501, TIP Numbers K-4003 and R-
2551.
The site is designed to provide 0.11 acres of restoration (1:1) and 1.66 acres of creation
(1:1) of Estuarine Fringe wetlands. The site also includes 1.29 acres (5:1) of estuarine
preservation. In addition, approximately 1,004 feet of riparian buffer was planted with
the same vegetation mix as that used in the wetland zones. The width of the buffer
zone varies between 9 and 65 feet based on NCDOT property limits. The construction
plan for the wetland sites involved grading the former borrow pit areas to meet the
elevations of adjacent jurisdictional wetlands.
1.2 Purpose
In order to demonstrate successful mitigation, hydrologic and vegetative monitoring
must be conducted for a minimum of five years or until success criteria are fulfilled.
Success criteria are based on federal guidelines for wetland mitigation and are
stipulated in the “Roanoke Island Visitor Center/ Rest Area Mitigation Plan” dated May
2001 (revised July 2001). These guidelines stipulate criteria for both hydrologic
conditions and vegetation survival. The following report details the results of hydrologic
and vegetative monitoring during 2006 at the Roanoke Island Mitigation Site.
Activities in 2006 reflect the fifth year of hydrology monitoring and the first year of
vegetation monitoring at the mitigation site. Included in this report are analyses of both
hydrologic and vegetative monitoring results, as well as local climate conditions
throughout the growing season.
3
Figure 1. Site Location Map
Roanoke Island Mitigation Site
US 64/264 Bypass
4
1.3 Project History
March 2002 Construction Completed
March 2002 Monitoring Gauges Installed
March 2002 Site Planted
March- November 2002 Hydrologic Monitoring (Year 1)
June 2002 Vegetation Monitoring (Year 1)
March- November 2003 Hydrologic Monitoring (Year 2)
September 2003 Vegetation Monitoring (Year 2)
February 2004 Site Replanted
March- November 2004 Hydrologic Monitoring (Year 3)
July 2004 Vegetation Monitoring (Year 1 Restart)
March 2005 Site Replanted
March- November 2005 Hydrologic Monitoring (Year 4)
August 2005 Vegetation Monitoring (Year 1 Restart)
March 2006 Applied Soil Amendments and Tilled Site
March 2006 Site Replanted
March- November 2006 Hydrologic Monitoring (Year 5)
August 2006 Vegetation Monitoring (Year 1 Restart)
2.0 HYDROLOGY
2.1 Success Criteria
While a constructed site must typically meet jurisdictional criteria of inundation or
saturation within 12 inches of the surface for at least 12.5% of the growing season,
NCDOT and consulting agencies agreed that other criteria might be the best indicator of
hydrologic success on this particular site. In accordance with the guidelines set forth by
the approved mitigation plans, hydrologic success is dictated by the hydrologic condition
of the reference wetlands adjacent to the sites. Monitoring gauges are located in both
the constructed and reference areas. The site is considered a hydrologic success if the
hydrologic frequency, duration and depth are within 20% of its respective reference
wetland.
The growing season in Dare County begins March 13 and ends November 25. The
dates correspond to a 50% probability that temperatures will drop to 28o F or lower after
5
March 13 and before November 25.1 The growing season is 258 days; therefore the
optimum duration for wetland hydrology is 32 days. While the monitoring gauges record
ground/surface water levels throughout the year, special attention is placed on water
levels during the 258-day growing season. In addition, local rainfall totals are monitored
to ensure that the site is functioning in normal climatic conditions.
2.2 Hydrologic Description
The site was constructed by grading the existing fill material down to meet the
elevations of existing reference wetlands. The removed fill material is associated with
borrow pit/ spoil basins that were previously onsite. Eleven monitoring gauges were
installed on the site in order to monitor the new hydrologic conditions. Three gauges
were located on the north tract and eight gauges were located on the south tract. Of
these, one gauge is located within the north tract reference wetland, while four gauges
are located within reference areas in the south tract. The success of the site is
determined by comparing the groundwater levels in the reference areas with those in
the constructed zones.
Site rainfall is monitored with a rainfall gauge located onsite. In addition, the recorded
data is compared to rainfall data at the Manteo Airport gauge in order to check the
accuracy of the measured data. The NC State Climate Office provided the Manteo
data. Figures 2 and 3 are monitoring gauge maps of the north and south tracts,
respectively.
2.3 Results of Hydrologic Monitoring
2.3.1 Site Data
Table 1 is a summary of the hydrologic monitoring results for both the north and south
tracts. The mitigation plan states that the hydrologic conditions of the constructed areas
must be within 20% of those in the reference areas. Figures 4 and 5 are
representations of the hydrologic monitoring results.
Appendix A contains a plot of the groundwater depth for each monitoring gauge. While
success of the site is based on reference wetlands and not the percentage of the
growing season that the groundwater is within 12 inches of the surface, the 12-inch line
is provided for reference. The number of days the water level was above this line is
also provided on each graph. Precipitation events, as recorded by the onsite rain
gauge, are included on each graph as bars.
1 Natural Resources Conservation Service, Soil Survey of Dare County, North Carolina, p.69.
6
Figure 2. Gauge Location Map - North Tract
7
Figure 3. Gauge Location Map - South Tract
8
Table 1. Hydrologic Monitoring Results
Monitoring
Gauge
< 5%
5 - 12%
> 12.5%
20% Saturation
Criteria to
Reference
Actual
Consecutive %
Dates of
Success
North Tract
RINT-1 r r 96.9 March 21-Nov 25
RINT-2 r
53.9
March 21-August
6
August 22-Nov
25
RINT-3 (ref) r 100 March 13-Nov 25
South Tract
RIST-1 r 63.2 March 13-Aug 22
RIST-2 (ref) r 100 March 13-Nov 25
RIST-3 (ref) r 100 March 13-Nov 25
RIST-4 r
67.4 March 13- Sept 2
Sept 30-Nov 25
RIST-5 (ref) r
77.9 March 13-Sept
29
RIST-6 r r 100 March 13-Nov 25
RIST-7 (ref) r
57.4 March 13-Aug 7
Aug 18-Nov 25
RIST-8 r r 100 March 13-Nov 25
Notes: “RINT” denotes gauges on the northern tract.
“RIST” denotes gauges on the southern tract.
“ref” denotes gauges in preservation areas of the site, used as reference wetlands.
Specific Gauge Problems:
• RIST-1 experienced gauge and battery malfunctions during (August 23-
September 29) and (October 6-October 26).
• RIST-4 experienced a gauge malfunction during (September 3-September 29).
• RIST-5 experienced a gauge malfunction during (September 30-October 26).
9
10
11
2.3.2 Climatic Data
Figure 6 provides an evaluation of the local climate in comparison with historical data in
order to determine whether 2006 was “normal” in terms of climate conditions. The two
lines represent the 30th and 70th percentiles of monthly precipitation for Manteo, NC. The
bars are monthly rainfall totals for 2006. The historical data was collected from the State
Climate Office of North Carolina.
For the 2006 year the below average rainfall includes; February, March, August, and
October. January, April, May, June, and July experienced average rainfall. The months
of September and November experienced above average rainfall for the year. Overall
the site experienced average rainfall in 2006.
2.4 Conclusions
Data from the fifth year of hydrologic monitoring indicates that all eleven monitoring
gauges demonstrated saturation within 12 inches of the surface for at least 12.5% of the
growing season. Gauge RIST-7 (ref) was moved to a more suitable location based on
similar elevation in August 2005, and met saturation within 12 inches of the surface for
57.4% of the growing season.
RINT-1 met within the 20% saturation period, while RINT-2 did not meet the saturation
period for the corresponding reference gauge RINT-3. RIST-1 and RIST-4 did not
meet the 20% saturation period for their corresponding reference gauges. RIST-5 met
the 20% saturation period, meeting approximately 80% of the growing season with it’s
corresponding reference gauge RIST-6. RINT-8 met the 20% saturation period by
exceeding the corresponding reference gauge. RIST-1 and RIST-4 experienced gauge
malfunctions during the growing season, however these gauges would have met the
20% saturation period for it’s corresponding reference gauge had it not been for gauge
malfunctions.
NCDOT recommends that hydrologic monitoring continue on the Roanoke Island
Mitigation Site.
12
Figure 6. 30-70 Percentile Graph
Roanoke Island
30-70 Percentile Graph
Manteo, NC
0
2
4
6
8
10
12
14
16
Nov-05 Dec-05 Jan-06 Feb-06 Mar-06 Apr-06 May-06 Jun-06 Jul-06 Aug-06 Sep-06 Oct-06 Nov-06
Date
Precipitation (in)
2005 Rainfall 2006 Rainfall 30th Percentile 70th Percentile
30th Percentile
70th Percentile
13
3.0 VEGETATION: ROANOKE ISLAND VISITOR CENTER
(YEAR 1 MONITORING)
3.1 Success Criteria
The success criteria state that there must be a minimum of 320 trees per acre living for
at least three consecutive years. A minimum of 290 trees per acre living at year 4 and a
minimum of 260 trees per acre living at year 5.
3.2 Description of Species
The following tree species were planted in the Wetland Enhancement Area:
Taxodium distichum, Baldcypress
Myrica cerifera, Wax Myrtle
Persea palustris, Swamp Redbay
Nyssa sylvatica var. biflora, Swamp Blackgum
Gordonia lasianthus, Loblolly Bay
Chamaecyparis thyoides, Atlantic White Cedar
3.3 Results of Vegetation Monitoring
The 2006 vegetation monitoring revealed that very few hardwood species were
surviving. Baldcypress, swamp blackgum, and wax myrtles were noted surviving in
vegetation plots 1, 2, and 3. There were no trees surviving in vegetation plot 4.
Site Notes: Other species noted: Juncus sp., cattail, woolgrass, pine, golden rod, water
grass, Scripus americanus, Pluchea sp., sawgrass, phragmites, marsh-elder, and
Baccharis halimifolia.
3.4 Conclusions
Approximately 1.8 acres of the site were planted in the wetland restoration and creation
areas in March 2002. The site was replanted in February 2004 and March 2005. In an
attempt to achieve greater survival rate of planted hardwood vegetation on the site, the
following steps were conducted in March 2006. NCDOT applied treatment of 1 ton of
gypsum and 1 ton of hydrated lime. The site was tilled and planted with bareroot
seedlings on four-foot centers. The 2006 vegetation monitoring revealed that these
steps failed on the site. The planted hardwood vegetation were surviving in very low
numbers due to the high soluble salt levels on the site, however the baldcypress,
swamp blackgum, and wax myrtle were noted as surviving in small numbers.
14
During construction of the mitigation site in 2002, approximately 0.29 acres of wetland
preservation area was inadvertently cleared. These mechanized clearing areas are
adjacent to the creation areas on the North and South Tracts. This activity was
referenced in a letter to the Corps dated March 6, 2002. Per the letter to the Corps, the
preservation areas have been replanted. NCDOT will continue to provide photo
documentation of the mechanized clearing areas to show the progression of the area
returning to its original state.
NCDOT will coordinate with the resource agencies in 2007 to determine the appropriate
action that needs to be taken to provide the required mitigation at the Roanoke Island
Visitors Center.
4.0 OVERALL CONCLUSIONS/ RECOMMENDATIONS
There are three gauges located in the north tract with two gauges in the constructed
area and one gauge in the reference area. There are eight gauges located in the south
tract with four gauges in the constructed area and four corresponding gauges in the
reference area. For the three north tract gauges, only one of the gauges met the 20%
saturation period for it’s respective reference gauge. For the eight south tract gauges,
two of the gauges met the 20% saturation period for their respective reference gauges.
The two gauges that failed, would have met the 20% saturation period for it’s
corresponding reference gauge had it not been for gauge malfunctions.
Data from the fifth year of hydrologic monitoring indicates that all eleven monitoring
gauges demonstrated saturation within 12 inches of the surface for at least 12.5% of the
growing season. Gauge RIST-7 (ref) was moved to a more suitable location based on
similar elevation in August 2005, and met saturation within 12 inches of the surface for
57.4% of the growing season.
This site was replanted with bareroot seedlings in March 2006. Due to high soluble salt
levels at the site, the hardwood vegetation is surviving in very low numbers. The
preservation areas that were inadvertently cleared during construction of the site in
2002 were replanted. Photo documentation of the mechanized clearing areas will
continue to be provided to show the progression of the area returning to its original
state.
NCDOT will continue to monitor the Roanoke Island Mitigation Site for hydrology and
vegetation. NCDOT will coordinate with the resource agencies in 2007 to determine the
appropriate action that needs to be taken to provide the required mitigation at the
Roanoke Island Visitors Center.
APPENDIX A
GAUGE DATA GRAPHS
APPENDIX B
SITE PHOTOGRAPHS
PHOTO AND VEGETATION PLOT LOCATIONS
MECHANIZED CLEARING PHOTOGRAPHS
MECHANIZED CLEARING IMPACT AREAS
ROANOKE ISLAND VISITOR CENTER
Photo 1 Photo 2
Photo 3 Photo 4
Photo 5 Photo 6
August 2006
ROANOKE ISLAND VISITOR CENTER
Photo 7
August 2006
ROANOKE ISLAND VISITOR CENTER
Mechanized Clearing Photographs
Photo 1 Photo 2
Photo 3 Photo 4
Photo 5 Photo 6
January 2007
ROANOKE ISLAND VISITOR CENTER
Mechanized Clearing Photographs
Photo 7 Photo 8
January 2007
Mechanized Clearing Impact Areas – South Tract
Mechanized Clearing Impact Areas – North Tract
APPENDIX A
GAUGE DATA GRAPHS
GROUND WATER GAUGES
Roanoke Island (North Tract) RINT-1
40" Groundwater
-30
-25
-20
-15
-10
-5
0
5
10
01-Jan-05
12-Jan-05
23-Jan-05
03-Feb-05
14-Feb-05
25-Feb-05
08-Mar-05
19-Mar-05
30-Mar-05
10-Apr-05
21-Apr-05
02-May-05
13-May-05
24-May-05
04-Jun-05
15-Jun-05
26-Jun-05
07-Jul-05
18-Jul-05
29-Jul-05
09-Aug-05
20-Aug-05
31-Aug-05
11-Sep-05
22-Sep-05
03-Oct-05
14-Oct-05
25-Oct-05
05-Nov-05
16-Nov-05
27-Nov-05
08-Dec-05
Date
Depth to Groundwater (in)
0
1
2
3
4
5
6
7
8
Precipitation (in)
Rainfall RINT-1 S448A7C Required Depth
Beginning of
growing season
End of
growing season
221 days
Gauge Malfunction
Gauge malfunction
unreliable rainfall data
Roanoke Island (North Tract) RINT-2
40" Groundwater
-30
-25
-20
-15
-10
-5
0
5
10
01-Jan-05
11-Jan-05
21-Jan-05
31-Jan-05
10-Feb-05
20-Feb-05
02-Mar-05
12-Mar-05
22-Mar-05
01-Apr-05
11-Apr-05
21-Apr-05
01-May-05
11-May-05
21-May-05
31-May-05
10-Jun-05
20-Jun-05
30-Jun-05
10-Jul-05
20-Jul-05
30-Jul-05
09-Aug-05
19-Aug-05
29-Aug-05
08-Sep-05
18-Sep-05
28-Sep-05
08-Oct-05
18-Oct-05
28-Oct-05
07-Nov-05
17-Nov-05
27-Nov-05
07-Dec-05
Date
Depth to Groundwater (in)
0
1
2
3
4
5
6
7
8
Precipitation (in)
Rainfall RINT-2 S448955 Required Depth
182 days
74 days
Beginning of
growing season End of
growing season
Gauge malfunction
unreliable rainfall data
Roanoke Island (North Tract) RINT-3
40" Groundwater Reference Gauge
-30
-25
-20
-15
-10
-5
0
5
10
01-Jan-05
11-Jan-05
21-Jan-05
31-Jan-05
10-Feb-05
20-Feb-05
02-Mar-05
12-Mar-05
22-Mar-05
01-Apr-05
11-Apr-05
21-Apr-05
01-May-05
11-May-05
21-May-05
31-May-05
10-Jun-05
20-Jun-05
30-Jun-05
10-Jul-05
20-Jul-05
30-Jul-05
09-Aug-05
19-Aug-05
29-Aug-05
08-Sep-05
18-Sep-05
28-Sep-05
08-Oct-05
18-Oct-05
28-Oct-05
07-Nov-05
17-Nov-05
27-Nov-05
07-Dec-05
Date
Depthto Groundwater (in)
0
1
2
3
4
5
6
7
8
Precipitation (in)
Rainfall RINT-3 S4489CD Required Depth
258 days
Beginning of
growing season
End of
growing season
Gauge malfunction
unreliable rainfall data
Roanoke Island (South Tract) RIST-1
40" Groundwater
-45
-35
-25
-15
-5
5
01-Jan-05
12-Jan-05
23-Jan-05
03-Feb-05
14-Feb-05
25-Feb-05
08-Mar-05
19-Mar-05
30-Mar-05
10-Apr-05
21-Apr-05
02-May-05
13-May-05
24-May-05
04-Jun-05
15-Jun-05
26-Jun-05
07-Jul-05
18-Jul-05
29-Jul-05
09-Aug-05
20-Aug-05
31-Aug-05
11-Sep-05
22-Sep-05
03-Oct-05
14-Oct-05
25-Oct-05
05-Nov-05
16-Nov-05
27-Nov-05
08-Dec-05
Date
Depth to Groundwater (in)
0
1
2
3
4
5
6
7
8
Precipitation (in)
Rainfall RIST-1 S44890F Required Depth
258 days
Beginning of
growing season
End of
growing season
Gauge malfunction
unreliable rainfall data
Roanoke Island (South Tract) RIST-2
40" Groundwater Reference Gauge
-30
-25
-20
-15
-10
-5
0
5
10
01-Jan-05
12-Jan-05
23-Jan-05
03-Feb-05
14-Feb-05
25-Feb-05
08-Mar-05
19-Mar-05
30-Mar-05
10-Apr-05
21-Apr-05
02-May-05
13-May-05
24-May-05
04-Jun-05
15-Jun-05
26-Jun-05
07-Jul-05
18-Jul-05
29-Jul-05
09-Aug-05
20-Aug-05
31-Aug-05
11-Sep-05
22-Sep-05
03-Oct-05
14-Oct-05
25-Oct-05
05-Nov-05
16-Nov-05
27-Nov-05
08-Dec-05
Date
Depth to Groundwater (in)
0
1
2
3
4
5
6
7
8
Precipitation (in)
Rainfall RIST-2 S448958 Required Depth
258 days
Beginning of
growing season End of
Gauge malfunction growing season
unreliable rainfall data
Roanoke Island (South Tract) RIST-3
40" Groundwater Reference Gauge
-30
-25
-20
-15
-10
-5
0
5
10
01-Jan-05
11-Jan-05
21-Jan-05
31-Jan-05
10-Feb-05
20-Feb-05
02-Mar-05
12-Mar-05
22-Mar-05
01-Apr-05
11-Apr-05
21-Apr-05
01-May-05
11-May-05
21-May-05
31-May-05
10-Jun-05
20-Jun-05
30-Jun-05
10-Jul-05
20-Jul-05
30-Jul-05
09-Aug-05
19-Aug-05
29-Aug-05
08-Sep-05
18-Sep-05
28-Sep-05
08-Oct-05
18-Oct-05
28-Oct-05
07-Nov-05
17-Nov-05
27-Nov-05
07-Dec-05
Date
Depth to Groundwater (in)
0
1
2
3
4
5
6
7
8
Precipitation (in)
Rainfall RIST-3 S448888 Required Depth
129 days
Beginning of
growing season
End of
growing season
Gauge Malfunction
88 days
Gauge malfunction
unreliable rainfall data
Roanoke Island (South Tract) RIST-4
40" Groundwater
-30
-25
-20
-15
-10
-5
0
5
10
01-Jan-05
11-Jan-05
21-Jan-05
31-Jan-05
10-Feb-05
20-Feb-05
02-Mar-05
12-Mar-05
22-Mar-05
01-Apr-05
11-Apr-05
21-Apr-05
01-May-05
11-May-05
21-May-05
31-May-05
10-Jun-05
20-Jun-05
30-Jun-05
10-Jul-05
20-Jul-05
30-Jul-05
09-Aug-05
19-Aug-05
29-Aug-05
08-Sep-05
18-Sep-05
28-Sep-05
08-Oct-05
18-Oct-05
28-Oct-05
07-Nov-05
17-Nov-05
27-Nov-05
07-Dec-05
Date
Depth to Groundwater (in)
0
1
2
3
4
5
6
7
8
Precipitation (in)
Rainfall RIST-4 S4488D6 Required Depth
188 days
Beginning of
growing season End of
growing season
43 days
Gauge Malfunction
Gauge malfunction
unreliable rainfall data
Roanoke Island (South Tract) RIST-5
40" Groundwater Reference Gauge
-30
-25
-20
-15
-10
-5
0
5
10
01-Jan-05
11-Jan-05
21-Jan-05
31-Jan-05
10-Feb-05
20-Feb-05
02-Mar-05
12-Mar-05
22-Mar-05
01-Apr-05
11-Apr-05
21-Apr-05
01-May-05
11-May-05
21-May-05
31-May-05
10-Jun-05
20-Jun-05
30-Jun-05
10-Jul-05
20-Jul-05
30-Jul-05
09-Aug-05
19-Aug-05
29-Aug-05
08-Sep-05
18-Sep-05
28-Sep-05
08-Oct-05
18-Oct-05
28-Oct-05
07-Nov-05
17-Nov-05
27-Nov-05
07-Dec-05
Date
Depth to Groundwater (in)
0
1
2
3
4
5
6
7
8
Precipitation (in)
Rainfall RIST-5 S4488EC Required Depth
258 days
Beginning of
growing season End of
growing season
Gauge malfunction
unreliable rainfall data
Roanoke Island (South Tract) RIST-6
40" Groundwater
-30
-25
-20
-15
-10
-5
0
5
10
01-Jan-05
11-Jan-05
21-Jan-05
31-Jan-05
10-Feb-05
20-Feb-05
02-Mar-05
12-Mar-05
22-Mar-05
01-Apr-05
11-Apr-05
21-Apr-05
01-May-05
11-May-05
21-May-05
31-May-05
10-Jun-05
20-Jun-05
30-Jun-05
10-Jul-05
20-Jul-05
30-Jul-05
09-Aug-05
19-Aug-05
29-Aug-05
08-Sep-05
18-Sep-05
28-Sep-05
08-Oct-05
18-Oct-05
28-Oct-05
07-Nov-05
17-Nov-05
27-Nov-05
07-Dec-05
Date
Depth to Groundwater (in)
0
1
2
3
4
5
6
7
8
Precipitation (in)
Rainfall RIST-6 S44886F Required Depth
258 days
Beginning of
growing season
End of
growing season
Gauge malfunction
unreliable rainfall data
Roanoke Island (South Tract) RIST-7
40" Groundwater Reference Gauge
-30
-25
-20
-15
-10
-5
0
5
10
01-Jan-05
12-Jan-05
23-Jan-05
03-Feb-05
14-Feb-05
25-Feb-05
08-Mar-05
19-Mar-05
30-Mar-05
10-Apr-05
21-Apr-05
02-May-05
13-May-05
24-May-05
04-Jun-05
15-Jun-05
26-Jun-05
07-Jul-05
18-Jul-05
29-Jul-05
09-Aug-05
20-Aug-05
31-Aug-05
11-Sep-05
22-Sep-05
03-Oct-05
14-Oct-05
25-Oct-05
05-Nov-05
16-Nov-05
27-Nov-05
08-Dec-05
Date
Depth to Groundwater (in)
0
1
2
3
4
5
6
7
8
Precipitation (in)
Rainfall RIST-7 S448998 Required Depth
Beginning of
growing season
End of
growing season
Gauge relocated
relative to RIST-8
elevation
258 Days
Gauge malfunction
unreliable rainfall data
Roanoke Island (South Tract) RIST-8
40" Groundwater
-30
-25
-20
-15
-10
-5
0
5
10
01-Jan-05
12-Jan-05
23-Jan-05
03-Feb-05
14-Feb-05
25-Feb-05
08-Mar-05
19-Mar-05
30-Mar-05
10-Apr-05
21-Apr-05
02-May-05
13-May-05
24-May-05
04-Jun-05
15-Jun-05
26-Jun-05
07-Jul-05
18-Jul-05
29-Jul-05
09-Aug-05
20-Aug-05
31-Aug-05
11-Sep-05
22-Sep-05
03-Oct-05
14-Oct-05
25-Oct-05
05-Nov-05
16-Nov-05
27-Nov-05
08-Dec-05
Date Depth to Groundwater (in)
0
1
2
3
4
5
6
7
8
Precipitation (in)
Rainfall RIST-8 S4487E0 Required Depth
258 days
Beginning of
growing season
End of
growing season
Gauge malfunction
unreliable rainfall data