Rowell Branch Tract

Rowel Branch Tract:
Year Four Monitoring Report
Brunswick County, NC
Prepared for:
ECOBANK
Winter Park, FL
Prepared by:
Land Management Group, Inc.
Wilmington, NC
December 2004
Tables, Figures, and Appendices
Table 1. Groundwater monitoring results for gauges located within the Rowel Branch Tract ....... 4
Table 2. Frequency and duration of flooding events for gauges at the Rowel Branch Tract .......... 5
Table 3. Number and type of trees planted at Rowel Branch in the spring of 2000 ........................6
Table 4. Number and species of trees surveyed within two transects at Rowel Branch .................7
Figure 1. Vicinity map ...................................................................................................................12
Figure 2. Topographic map of site and reference area ..................................................................13
Figure 3. Location of monitoring gauges at site ............................................................................14
Figure 4. The cross-section of each gauge transect .......................................................................15
Figure 5. Location of vegetation monitoring transects at site .......................................................16
Appendix A. Hydrographs
Figure B.1. Hydrology Monitoring, Gauge Al
Figure B.2. Hydrology Monitoring, Gauge A2
Figure B.3. Hydrology Monitoring, Gauge B 1
Figure B.4. Hydrology Monitoring, Gauge B2
Figure B.5. Hydrology Monitoring, Gauge C1
Figure B.6. Hydrology Monitoring, Gauge C2
Figure B.7. Hydrology Monitoring, Reference Gauge R1
Figure B.8. Hydrology Monitoring, Reference Gauge R2
Figure B.9. Normal Rainfall Distribution (2004)
Appendix B. Pictures of site
Appendix C. Vegetation data by transect
11
Monitoring Report for the
Rowel Branch Tract:
Year Four
1.0 Introduction
Throughout 2000 and 2001, ECOBANK restored 16.1 acres of bottomland hardwood
wetlands at the Rowel Branch tract (Figure 1) in Brunswick County, North Carolina. This restoration
was used as mitigation for unavoidable wetland impacts associated with the construction of the
Wilmington Bypass by the NCDOT. Details of the mitigation activities are presented in the Revised
Compensatory Mitigation Plan for the Rowel Branch Tract, dated July 21, 2000. Construction
activities were consistent with the mitigation plan.
The Rowel Branch tract consists of a riverine ecosystem, which was bypassed in the 1970's
with the construction of a large water diversion canal (Figure 2). In addition, four areas within this
floodplain were filled to facilitate better tract access during construction of an adjacent railroad yard.
In order to restore this tract, ECOBANK 1) removed the fill from these four different sections of the
site to restore the natural floodplain (winter of 2000), 2) planted trees within the floodplain (spring
of 2000), 3) removed the earthen plug that separated the natural stream and the canal (spring of
2001), and 4) filled the large diversion canal with the previously excavated material in order to
restore hydrology back to the stream and its floodplain (summer of 2001).
2.0 Hydrology
2.1 Success Criteria
According to the Rowel Branch Tract Mitigation Plan, two hydrological success
criteria were established. The first criterion ensures that wetland hydrology for this site is
achieved and requires the establishment of a static water table at or within 12" of the soil
surface, ponded or flooded for 12.5% of the growing season during normal precipitation
conditions. The growing season in Brunswick County extends 265 days, between March 7
and November 28. Normal precipitation is defined as total monthly precipitation falling
within the 30th and 70th percentiles of a 30-year period. Therefore, to meet the first success
criterion, the water table should remain at or within 12" of the soil surface for at least 33
consecutive days between March 7 and November 28. The second criterion deals with
riverine hydrology and requires the establishment of overbank flooding events at a frequency
and duration within 10% of the reference site.
2.2 Methods
Six automated groundwater monitoring gauges were installed throughout the Rowel
Branch site to monitor groundwater hydrology for at least five years (Figure 3). These
gauges were located within three transects, with each transect containing two gauges: one
within the stream channel and one 50' from the channel. Four of these gauges (A1, A2, B1,
and 132) were installed on July 20, 2000 and the remaining two gauges (C 1 and C2) were
installed on November 29, 2000. Two reference gauges located off site were installed on
July 29, 2000 (Figure 2). Each gauge was programmed to read the groundwater level once
a day.
In March of 2000, the channel in the restored wetland was restored to the grade of
the previous streambed, resulting in 2,640 linear feet of stream restoration to be utilized by
NCDOT. In June and July of 2001, the existing diversion canal was filled to divert all flow
back through the restored riverine system. The existing fill was removed and contoured to
natural grade. Topographical data and drainage calculations demonstrated that the restored
floodplain was lower and wider than the old canal; therefore the restoration would not cause
upstream flooding (see Appendix A). Also in July of 2001, NCDOT maintenance contractors
installed a second 7' drainage culvert under Mt. Misery Road to enhance downstream flow.
For this monitoring report, hydrology and riverine data between October of 2003 and
October of 2004 were analyzed. To evaluate the riverine success criterion, the cross-section
of each gauge transect was surveyed in 2002 (Figure 4) and the gauges were calibrated to
mean sea level so that water level data collected on site could be compared to reference
gauge data. The number of events (frequency) and the length of each event (duration) that
gauges documented overbank flooding between October of 2003 and October of 2004 were
calculated and compared to data from the reference gauges to evaluate this success criterion.
It should be noted that the riverine success criteria were not fulfilled during the second or
third year of monitoring (2002 and 2003).
2.3 Results
As in previous years, all six gauges located within Rowel Branch fulfilled the
wetland hydrology criterion of a water table within 12" of the soil surface for 12.5% of the
growing season, or 33 days (Table 1). Four of the six gauges recorded wetland hydrology
from the beginning of the growing season (March 7, 2004) until the last reading taken prior
to submitting this report (November 3, 2004). Two gauges (A2 & 132) located within the
stream at Rowel Branch stopped reading during the growing season. Based on data from
previous years, B2 most likely would have documented standing water throughout the year
had it continued to read. For most of the year, A2 was reading a water level at ground level
but fell below the 12" threshold twice during drier than normal conditions. The two reference
gauges (RI and R2) also exceeded the wetland hydrology criterion and had a water table
within 12" of the soil surface for the entire monitoring period.
The 30-day running total for 2004 shows normal to slightly below normal rainfall for
most of the year, except for late summer, which documented above normal rainfall
(Appendix A). Several hurricanes passed through the region during this time period.
3
Table 1. Groundwater monitoring results for gauges located within the Rowel Branch tract and
the reference site between March 7. 2004 and November 3. 2004.

Type Gauge
Number Serial
Number # of Consecutive Days
above 12"
Restoration Al S353B9B 242
A2 S353A32 80*
B1 S213EB6 242
B2 S369807 48*
C1 S353979 242
C2 S126F6B 242
Reference R1 S3539A7 242
R2 S126F2F 242
* Gauge stopped reading during the monitoring period.
An evaluation of the riverine success criterion determined the frequency and duration
of overbank flooding for all gauges within the tract and within the reference site (Table 2).
The gauge (R1) located in the reference stream documented overbank flooding on 10
occasions. Each flooding event had an average duration of 19.2 days. As in 2002 and 2003,
all three of the stream gauges at Rowel Branch experienced fewer flooding events and at a
shorter average duration than the reference stream gauge. Gauge Al experienced 6 flooding
events with an average duration of 6.2 days and gauge B 1 documented 6 flooding events
with average duration of 8.2 days. The stream gauge located farthest north (Cl) only
recorded 2 flooding events with an average duration of 1 day. None of the mitigation gauges
located at the stream met the success criterion of establishing overbank flooding events at
a frequency or duration within 10% of RI.
The gauge (R2) located 50' away from the reference stream documented flooding on
13 occasions, with an average duration of 8.4 days. The frequency of flooding events
documented at the mitigation gauges were lower (A2 (9), B2 (0), and C2 (6) than the
frequency observed at R2. A2 and C2 recorded longer durations of flooding events than the
4
reference gauge and did not meet the 10% success criterion for duration. B2 did not exhibit
any flooding events because it was malfunctioning during a majority of the monitoring
period.
Table 2. Frequency and duration of flooding events for gauges located within the Rowel Branch
tract and the reference site in 2004.

Type Gauge
Number Serial
Number Frequency of
Flooding Events Average Duration
of Flooding Events
(days)
Restoration Al S353B9B 6 6.2
A2 S353A32 9 11.8
B1 S213EB6 6 8.2
B2 S369807
C1 S353979 2 1
C2 S 126F6B 6 29.0
Reference RI S3539A7 10 19.2
R2 S 126F2F 13 8.4
* Gauge malfunctioned during a majority of the monitoring period.
As in previous years, it was observed throughout 2004 that beavers were building
dams in several locations within the creek, causing water levels near these dams to increase.
Because of concern raised by neighbors that these dams were backing up water onto their
property, the dams were periodically monitored and removed. The creek will continue to be
monitored for the reappearance of dams.
3.0 Vegetation
3.1 Success Criteria
The Rowel Branch Mitigation Plan states that the vegetation success criterion for this
project is the survival of 320 trees/acre, including acceptable volunteer species. In addition,
no individual hardwood species may account for more than 20% of the total number of
stems.
3.2 Methods
A list of the tree species that were planted in the spring of 2000 at the Rowel Branch
tract is given in Table 3. These one-year and two-year seedlings were obtained from the NC
Forest Service Nursery and were planted on a ten-foot spacing within the floodplain of
Rowel Branch. The vegetation survey consisted of establishing a circular plot every 25 feet
along two transects within the tract (Figure 5). The center of each plot was marked with a
pink pin flag and the ends of the transects were marked with orange flagging. Each plot had
a radius of 10 feet and an area of 314.2 ft2. Transect 1 contained 7.5 plots and transect 2
contained 6.5 plots. Therefore, the total area surveyed was 4398 ft2, or approximately 0.1
acre. Transect 1 was approximately 200 feet in length and began along the edge of a planted
area that was relatively high in elevation. Progressing along the transect, elevation gradually
dropped until the stream was encountered, which represented the lowest elevation and
wettest point along the transect. Then the elevation rose again as it moved toward the
stockpile area, where it ended. Transect 2 was approximately 175 feet in length. No major
changes in elevation were observed along this transect except for a low ponded spot in the
middle. The transect began at the canal, near where it turns 90E, and ended at the stream.
Table 3. Number and types of trees planted at Rowel Branch on March 15 and April 1 of 2000.
Trees were planted at a densitv of 435/acre.
Common Name Scientific Name # Planted
Atlantic White Cedar (2
yr) Chamaecyparis thyoides 1000
Bald Cypress (1 yr) Taxodium distichum 1600
Green Ash (1 yr) Fraxinus pennsylvanica 800
Water Oak (1 yr) Quercus nigra 1000
Willow Oak (1 yr) Quercus phellos 1300
Yellow Poplar (1 yr) Driodendron tulipifera 600
TOTAL 6300
6
3.3 Results
As in previous years, herbaceous vegetation observed within the drier areas of both
transects included Eupatorium capillifolium, E. hyssopifolium, and Rubus spp. In the wetter
areas, Scirpus cyperinus, Peltandra virginica, Mikania scandens, Juncus effusus, Polyganum
sagittatum, and several sedge species (Cyperus and Carex spp.) were observed. Again, more
herbaceous vegetation was observed in transect 1 than in transect 2, although transect 2 was
becoming dense in vegetation (Appendix Q.
The planted trees that were observed within the transects were in good condition and
continue to grow. Several bald cypress (Taxodium distichum) trees were over 10 feet tall.
Volunteer alder (Alnus serrulata) trees were found in wetter spots, especially near the stream
in transect 1. As in previous years, most of the red maple observed was in transect 2. The
number of red maple seedlings observed within the transects has decreased from 2003 and
the average size of the species has slightly increased.
Table 4. Number and species of trees surveyed within two transects at Rowel Branch (7/30/04)
Common Name Scientific Name Avera a
Height in) Total # of
Trees
Observed # Counted
Towards
Criteria
Alder Alnus serrulata 68.3 114 93.8
Atlantic White Cedar* Chamaec aris th oides 52.0 3 3
Bald C ress* Taxodium distichum 80.6 49 49
Black Willow Salix ni a 91.3 21 21
Eastern Baccharis Baccharis halimi olia 62.0 3 3
Eastern S camore* Platanus occidentalis 39.0 2 2
Green Ash Fraxinus pennsylvanica 75.5 12 12
Loblolly Pine Pinus taeda 51.35 26 26
Overcu Oak uercus 46.5 2 2
Red Maple Acer rubrum 50.2 186 93.8
Sweet um Li uidambar s raci ua 52.4 15 15
Wax Myrtle M rica ceri era 49.4 21 21
Willow Oak* uercus hellos 58.3 9 9
Win ed Sumac Rhus co allina 36.0 6 6
TOTAL 469 356.6
(Data for the individual transects are given in Appendix D.)
*Species was planted in 2000.
A total of 469 trees was observed within the surveyed plots (Table 4), which was
slightly less than the number of trees observed in 2003 (479). The mitigation plan stated that
no single tree species could represent more than 20% of the total number of trees observed.
After factoring in this requirement, the number that was counted towards the vegetation
success criterion was 356.6 trees, which was slightly greater than last year's value of 334.6.
Because the total area of all the plots represented approximately 0.1 acre, the average
number of trees/acre in 2004 was 3566. This was more than 10 times the minimum 320
trees/acre required by the mitigation plan. Therefore, vegetation met the success criterion
during year four monitoring.
4.0 Conclusions
ECOBANK has restored 16.1 acres of bottomland hardwood wetlands at the Rowel Branch
tract in Brunswick County, North Carolina as mitigation for unavoidable wetland impacts associated
with the construction of the Wilmington Bypass by the NCDOT. To restore this area, fill was
removed from the riverine floodplain, trees were planted within the floodplain, and a large diversion
canal was filled to restore hydrology to the stream.
As in previous years, groundwater monitoring data collected from automated gauges during
2004 showed Rowel Branch to support wetland hydrology. All six of the gauges on site and the two
reference gauges demonstrated groundwater levels at or within 12" of the soil surface for at least
12.5% of the growing season (33 days). In fact, four of the gauges located at Rowel Branch recorded
wetland hydrology from the beginning of the growing season (March 7, 2004) until the last reading
taken prior to submitting this report (November 3, 2004). The two gauges that demonstrated a
shorter wetland hydrology stopped working during the monitoring period.
An evaluation of the riverine success criterion determined the frequency and duration of
overbank flooding within the tract and within the reference site. As in 2002 and 2003, this evaluation
did not determine a clear pattern between gauges. The reference gauge located within the stream
(RI) documented flooding on 10 occasions, with an average duration of 19.2 days. All three of the
gauges located within the restored stream at Rowel Branch (Al, Bl, and Cl) experienced fewer
flooding events and shorter flooding durations than this reference and did not meet the 10% success
criterion for frequency or duration.
The reference gauge located 50' away from the stream (R2) documented flooding on 13
occasions, with an average duration of 8.4 days. Because B2 malfunctioned for most of the
monitoring period, it did not record any flooding events and cannot be compared to R2. The other
two gauges located 50' from the stream at Rowel Branch (A2 and C2) recorded fewer flooding
events yet longer durations of flooding than what was recorded at R2. Neither A2 nor C2 met the
10% success criterion for frequency or duration.
The cross-sections showed that the reference stream at its transect location is smaller in area
than the restored stream at those transect locations. Therefore, when comparing these points, the
reference stream gauge floods more frequently. This has been documented in each monitoring
report. However, no clear pattern has been observed for the gauges located 50' from the stream. In
2004, Gauges A2 and C2 (132 malfunctioned) documented fewer flooding events than R2 yet with
longer average durations. In 2003, A2, B2, and C2 documented more or the same number of
flooding events with longer average durations than R2. In 2002, A2 and C2 recorded more flooding
events with a shorter duration and B2 recorded fewer flooding events with a longer average flooding
duration.
Another pattern that has been consistent at Rowel Branch is that the A and C transects have
experienced more frequent flooding events 50' away from the stream than directly adjacent to the
stream even though the gauges 50' away from the stream were at higher elevations than the top of
the bank. This may be because the topography is flatter 50' away from the stream and short-term
rainfall can create ponding in these areas. Closer to the stream, slopes are greater and rainfall is
transported at a fast rate downstream, decreasing overbank flooding.
As discussed in previous monitoring reports, there are several reasons why the riverine
success criterion was largely not achieved. First, the reference stream is located in the middle of
Leland Industrial Park and receives a large amount of stormwater runoff from impervious cover
associated with this development, which may cause additional flooding. Property surrounding Rowel
Branch is mostly small residential units or undeveloped parcels, which contribute less stormwater
flow into the restored stream. In addition, the dimensions of the restored stream were not based on
those of the reference stream. The unchannelized bottomland hardwood reference site was chosen
as a general control for groundwater hydrology. Site selection of the gauge placement was not based
on similar cross-sectional profile data between the reference and the restored sites. Therefore,
overbank flooding results are difficult to compare particularly when the four transects were selected
at random with no pre-project elevation information.
Just like most coastal streams, Rowel Branch's stream bank heights show great variability
and, therefore, overbank flooding events should not be referenced to one spot along an entire stream
gradient. Rack lines, fresh sediment buildup, and compressed herbaceous plant stems are better
indicators of flooding throughout the system. Further compounding the comparative results of
random monitoring points is the braided nature of the coastal floodplain. In one instance, the
reference gauge may be situated near a lower shelf braided branch of the main stream while the
restoration gauge may be on a higher position on the floodplain. It is important to look at the entire
system rather than at individual points. The requirement that all restored gauges must be within 10%
of one sample reference transect is too restrictive and does not account for the high variability of the
coastal bottomland hardwood stream system. A better solution would be to put more importance on
achieving survivability of similar hydrophytic plants and maintaining wetland hydrology over the
course of five years. Flooding events could be modeled with a design storm of a certain event (i.e.
10, 25 or 50-year) and then compare the extent of flooding over the four transects. In this manner
one can project the flooding dissipation function of the floodplain in both reference and restored
sites in a manner similar to FEMA and stormwater/sediment control models.
However, because the Rowel Branch gauges documented frequent flooding events and
because wetland vegetation is flourishing throughout the site, it is achieving its overall goal of
restoring a riverine floodplain system. As stated in previous monitoring reports, the riverine success
criterion appears to be too restrictive and may need to be redefined by the commenting agencies.
The vegetation analysis determined a total of 469 trees within the surveyed plots (Table 4),
a slight decrease from the 479 trees observed in 2003. This decrease was mostly a result of fewer
red maple and alder trees, which are starting to thin out as individuals get older. After factoring in
percentage requirements, the number of trees that were counted towards the vegetation success
10
criterion was 356.6 trees, or 3566 trees/acre. This was more than 10 times the minimum 320
trees/acre required by the mitigation plan and was an increase in number from monitoring performed
in 2001 (205.6), 2002 (214.2), and 2003 (334.6). It should be noted that planted species continue to
grow taller in each successive year, especially bald cypress. The mean height for cypress trees in
2004 was 6.8 feet, up from 5.5 feet observed in 2003. Therefore, vegetation met the success criterion
during year four monitoring.
Based on the data analysis within this report, the conclusion of the year four monitoring is
that the Rowel Branch tract has fulfilled the vegetation and hydrology success criteria established
in the mitigation plan and that the wetland restoration of the tract is thus far successful.
11
Table 1. Number and tune of trees observed in Transect 1 in 2004.
Common Name Scientific Name Avera( nHeight # Observed
Atlantic White Cedar Chamaecyparis thyoides 52.0 3
Bald Cypress Taxodium distichum 82.13 32
Black Willow Salix nigra 85.71 14
Common Alder Alnus serrulata 73.50 48
Eastern Baccharis Baccharis halimifolia 62.0 3
Green Ash Fraxinus pennsylvanica 72.0 6
Loblolly Pine Pinus taeda 34.29 21
Overcup Oak Quercus lyrata 54.0 1
Red Maple Acer rubrum 42.63 38
Sweetgum Liquidambar styraciflua 52.40 15
Water Oak Quercus nigra 36.0 1
Wax Myrtle Myrica cerifera 49.43 21
Willow Oak Quercus phellos 54.86 7
Winged Sumac Rhus copallina 36.0 6
TOTAL 216
Table 2. Number and tune of trees observed in Transect 2 in 2004
Common Name Scientific Name Average Height
in # Observed
Bald Cypress Taxodium distichum 79.06 17
Black Willow Salix nigra 96.86 7
Common Alder Alnus serrulata 63.0 66
Green Ash Fraxinus pennsylvanica 79.0 6
Loblolly Pine Pinus taeda 68.4 5
Overcup Oak Quercus lyrata 18.0 1
Red Maple Acer rubrum 57.69 148
Sycamore Platanus occidentalis 39.0 2
Willow Oak Quercus phellos 84.0 1
TOTAL 253
Figure 1. Hydrology Monitoring, Gauge A 1
Rowel Branch Tract; Restoration
2004
36
beginnin
30
24
18
A 12
xib 6
3
c
0 0
0
O -6
-12
-18
of growing season
-------?-
-----

- -
---------------------------- - ----
--------------------------- -------
242 days
------- ---- ------ -----------------
- - - - - - - - - - - - - - - - - - -
------------ ---------------------------------- ----------

-24
0o pa o° o° cP o° o° cP Q? o?` ct. cP QP- Qp? o° cP` Q;. cp? Q?- d. cP o°`
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6
5
4
3
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2
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0
;,.Al (S35313913)-12"below surfacd!MRainfall (i )
Rainfall information provided by the State Climate Office
of North Carolina at North Carolina State University; Note: 1 reading/day
Wilmington International Airport station.
Figure 2. Hydrology Monitoring, Gauge A2
Rowel Branch Tract; Restoration
2004
36
beginn
30
24
18
12
Q
b 6
3
0
0
Ur -6
-12
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-24
g of growing seas
--------*?
------------- -------------------------------- -
-----------------------------------------------
-------------
------------ -----------------------------------------------
------------------------------y:'---------------
------------ -----------------------------------------------
80 days gauge stoppe
working
------------ -------- „ '-- --- -----------

6
5
4
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>v.
3
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1
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-4 A2 (S353A32)-12"below surfacMIRainfa I
Rainfall information provided by the State Climate Office
of North Carolina at North Carolina State University; Note: 1 reading/day
Wilmington International Airport station.
Figure 3. Hydrology Monitoring, Gauge B1
Rowel Branch Tract; Restoration
2004
36
30
24
18
0 12
6
0
0
-6
-12
-18
-24
6
5
4
3
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1

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171B (S210DA5)-12"below surfacdERainfa I
Rainfall information provided by the State Climate Office
of North Carolina at North Carolina State University;
Wilmington International Airport station.
Figure 4. Hydrology Monitoring, Gauge B2
Rowel Branch Tract; Restoration
2004
36
30
24
18
fl, 12
b 6
3
v
0
5 -6
-12
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-24
-------- - -

-------------
_beginning- of-gro ---------- ----------------- -
242 days
----- -------------
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ng-season _______________________________________
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-----
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Note: 1 reading/day
------------ -----------------------------------------------
-beginning of growl g season
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----------- ----------------------------L-4 --- a -----.
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Rainfall information provided by the State Climate Office
6
5
4
3
1
0
of North Carolina at North Carolina State University; Note: I reading/day
Wilmington International Airport station.
Figure 5. Hydrology Monitoring, Gauge C1
Rowel Branch Tract; Restoration
2004
36
30
24
c 18
12
b 6
3
b
0
0
C5 -6
-12
-18
-24
------------ ---------------------------------------------
beginningotgrow gseason ---------------------------------------
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a 242 days
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6
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?:,,Cl (S353979)-12'below surfacdERainfa 1
Rainfall information provided by the State Climate Office
of North Carolina at North Carolina State University;
Wilmington International Airport station.
Figure 6. Hydrology Monitoring, Gauge C2
Rowel Branch Tract; Restoration
2004
36
30
24
18
12
?ht 6
3
c
? 0
-6
-12
-18
-24
Note: I reading/day
-----------------------------------------------------------
_beginningof_aro ng-season ______________________________________
----------------------------------------------
-------------------------------------------- -----------
242 days
- - - - _ _ - - _ _ 4_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
A-A ---------------
o°`
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?aC2 (5353984)-12"below surfacdERamfall (,I)
Rainfall information provided by the State Climate Office
6
5
4
3
2
1
0
of North Carolina at North Carolina State University; Note: 1 reading/day
Wilmington International Airport station.
Figure 7. Hydrology Monitoring, Gauge Rl
Rowel Branch Tract; Reference
36 2004
30
24
c 18
12
b 6
3
C
7 0
-6
-12
-18
-24
V V \T ?\T ?V11 Ob V QSQ? 4 ?ZT d, V11
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beginning of growl season
----------- ----------------------------- -------------
-----------
242 days
-------------- - ------- --------
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
------------------------------------ -----------
6
5
4
3
o'
2
1
0
Rainfall information provided by the State Climate Office
of North Carolina at North Carolina State University; Note: 1 reading/day
Wilmington International Airport station.
Figure 8. Hydrology Monitoring, Gauge R2
Rowel Branch Tract; Reference
2004
36
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beginning of growl
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-sR2 (S3539A7)-12"below surfacMIRainfall (i )
Rainfall information provided by the State Climate Office
of North Carolina at North Carolina State University; Note: 1 reading/day
Wilmington International Airport station.
A.
ii
ua f 3'
Rowel Branch Tract:
Year Two Monitoring Report
Brunswick County, NC
Prepared for:
ECOBANK
Winter Park, FL
Prepared by:
Land Management Group, Inc.
Wilmington, NC
November 2002
A_16
Table of Contents
1.0 Introduction .......................................................................................................................1
2.0 Hydrology ...........................................................................................................................1
2.1 Success Criteria ..........................................:..............................................................1
2.2 Methods ....................................................................................................................2
2.3 Results .......................................................................................................................3
3.0 Vegetation ..............................................
3.1 Success Criteria ............................
3.2 Methods .......................................
3.3 Results .........................................
........................................................................... 6
........................................................................... 6
........................ ................................................ 6
........................................................................... 7
4.0 Conclusions .....................................................:...................................................................9

Tables, Figures, and Appendices
Table 1. Groundwater monitoring results for gauges located within the Rowel Branch Tract . ...... 4
Table 2. Frequency and duration of flooding events for gauges at the Rowel Branch Tract.......... 5
Table 3. Number and type of trees planted at Rowel Branch in the spring of 2000 ....................... 7
Table 4. Number and species of trees surveyed within two transects at Rowel Branch ................. 8
Figure 1. Vicinity map ...............................................................................................................12
Figure 2. Topographic map of site and reference area ................................................................13
Figure 3. Location of monitoring gauges at site .........................................................................14
Figure 4. The cross-section of each gauge transect ....................................................................15
Figure 5. Location of vegetation monitoring transects at site .....................................................16
Appendix A. Engineering Report performed by Wrightsville Engineering Services
Appendix B. Hydrographs
Figure B.1. Hydrology Monitoring, Gauges Al & A2
Figure B.2. Hydrology Monitoring, Gauges B1 & B2
Figure B.3. Hydrology Monitoring, Gauges Cl & C2
Figure B.4. Hydrology Monitoring, Reference Gauges RI & R2
Figure B.5. Normal Rainfall Distribution (2001-2002)
Appendix C. Pictures of site
Appendix D. Vegetation data by transect
ii

Monitoring Report for the
Rowel Branch Tract:
Year Two
1.0 Introduction
Throughout 2000 and 2001, ECOBANK has restored 16.1 acres of bottomland hardwood
wetlands at the Rowel Branch tract (Figure 1) in Brunswick County, North Carolina. This
restoration was used as mitigation for unavoidable wetland impacts associated with the
construction of the Wilmington Bypass by the NCDOT. Details of the mitigation activities are
presented in the Revised Compensatory Mitigation Plan for the Rowel Branch Tract, dated July
21, 2000. Construction activities were consistent with the mitigation plan.
The Rowel Branch tract consists of a riverine ecosystem, which was bypassed in the
1970's with the construction of a large water diversion canal (Figure 2). In addition, four areas
within this floodplain were filled to facilitate better tract access during construction of an adjacent
railroad yard. In order to restore this tract, ECOBANK 1) removed the fill from these four
different sections of the site to restore the natural floodplain (winter of 2000), 2) planted trees
within the floodplain (spring of 2000), 3) removed the earthen plug that separated the natural
stream and the canal (spring of 2001), and 4) filled the large diversion canal with the previously
excavated material in order to restore hydrology back to the stream and its floodplain (summer of
2001).
2.0 Hydrology
2.1 Success Criteria
According to the Rowel Branch Tract Mitigation Plan, two hydrological success
criteria were established. The first criterion ensures that wetland hydrology for this site is
achieved and requires the establishment of a static water table at or within 12" of the soil
A&__
surface, ponded or flooded for 12.5% of the growing season during normal precipitation
conditions. The growing season in Brunswick County extends 265 days, between March 7
and November 28. Normal precipitation is defined as total monthly precipitation falling
within the 30th and 7e percentiles of a 30-year period. Therefore, to meet the first success
criterion, the water table should remain at or within 12" of the soil surface for at least 33
consecutive days between March 7 and November 28. The second criterion deals with
riverine hydrology and requires the establishment of overbank flooding events at a
frequency and duration within 10% of the reference site.
2.2 Methods
Six automated groundwater monitoring gauges were installed throughout the
Rowel Branch site to monitor groundwater hydrology for at least five years (Figure 3).
These gauges were located within three transects, with each transect containing two
gauges: one within the stream channel and one 50' from the channel. Four of these gauges
(Al, A2, B1, and B2) were installed on July 20, 2000 and the remaining two gauges (C1
and C2) were installed on November 29, 2000. Two reference gauges located off site
were installed on July 29, 2000 (Figure 2). Each automated gauge reads the groundwater
level once a day.
In March of 2000, the channel in the restored wetland was restored to the grade of
the previous streambed, resulting in 2,640 linear feet of stream restoration to be utilized by
NCDOT. In June and July of 2001, the existing diversion canal was filled to divert all flow
back through the restored riverine system. The existing fill was removed and contoured to
natural grade. Topographical data and drainage calculations demonstrate that the restored
floodplain is lower and wider than the old canal; therefore the restoration will not cause
upstream flooding (see Appendix A). Also in July of 2001, NCDOT maintenance
contractors installed a second 7' drainage culvert under Mr. Misery Road to enhance
downstream flow.
2

The riverine success criterion was not evaluated in the year one monitoring report
because the diversion canal was not filled until the summer of 2001 and a sufficient
amount of data could not be analyzed. For this monitoring report, data between June of
2001 (when the canal was filled) and September of 2002 were analyzed. To evaluate the
riverine success criterion, the cross-section of each gauge transect was surveyed in 2002
(Figure 4) and the gauges were calibrated to mean sea level so that water level data
collected on site could be compared to reference gauge data. The number of events
(frequency) and the length of each event (duration) that gauges documented overbank
flooding between June of 2001 (when the diversion canal was filled) and September of
2002 was calculated and compared to data from the reference gauges to evaluate this
success criterion.
2.3 Results
All six gauges located within Rowel Branch-fulfilled the wetland hydrology
criterion of a water table within 12" of the soil surface for 12.5% of the growing season,
or 33 days (Table 1). Two gauges (Al & Bl) located within the stream stopped reading
during the growing season and most likely would have documented standing water
throughout the year had they continued to read. Of the two reference gauges, the gauge
within the stream (RI) far exceeded the wetland hydrology criterion and had a water table
within 12" of the soil surface for 190 consecutive days. The other gauge (R2) stopped
reading during part of the 2002 growing season, yet still documented wetland hydrology
for 38 days.
The 30-day running total for 2002 shows below normal rainfall for approximately
five months; January, February, May, June, and part of August (Appendix B). It should be
noted that North Carolina experienced the driest recorded year between September of
2001 and August of 2002. However, rainfall in September of 2002 pushed the running
total far above average during this month. Because the gauges in the Rowel Branch site
have achieved the wetland hydrology criterion for 2002, the rainfall data reveal how wet
this site is, even with below average rainfall for much of the year.
3
A
--- ---------- -
Table 1. Groundwater monitoring results for gauges located within the Rowel Branch tract and the
reference site.
Type Gauge
Number Serial
Number # of Consecutive Days
above 12"
Restoration Al S35313913 91*
A2 S353A32 87
B1 S213EB6 95*
B2 S369807 60
C1 S353979 95
C2 S126F6B 46
Reference R1 S3539A7 190
R2 S126172F 38*
"Gauge stopped reading during the growing season.
An evaluation of the riverine success criterion determined the frequency and
duration of overbank flooding for all gauges within the tract and within the reference site
(Table 2). The reference gauge in the stream (RI) documented overbank flooding on 19
occasions. Each flooding event had an average duration of 10.4 days. All three of the
stream gauges at Rowel Branch experienced fewer flooding events and had shorter
durations. Gauges Al and B1 both documented 10 flooding events with average durations
of 4.3 days and 2.3 days, respectively. The stream gauge located farthest north (C 1) did
not document any flooding events. None of the mitigation gauges met the success
criterion of establishing overbank flooding events at a frequency and duration within 10%
of the reference site.
The reference gauge 50' away from the stream (R2) documented flooding on 7
occasions, with an average duration of 2.7 days. The number of flooding events
documented by the three mitigation gauges located 50' away from the stream were 11
(A2), 2 (B2), and 15 (C2). Again, none of the mitigation gauges met the success criterion
of establishing overbank flooding events at, a frequency and duration within 10% of the
reference site.
4

Table 2. Frequency and duration of flooding events for gauges located within the Rowel Branch
tract and the reference site.
Type Gauge
Number Serial
Number Frequency of
Flooding Events Average Duration of
Flooding Events
(days)
Restoration Al S353B913 10 4.3
A2 S353A32 11 2.3
B1 S213EB6 10 2.0
B2 S369807 2 26.0
C1 S353979 0 -
C2 S 126F6B 15 1.9
Reference R1 S3539A7 19 10.4
R2 S 126F2F 7 2.7
It was observed throughout the year that beavers were building dams in several
locations within the creek, causing water levels near these dams to increase. Because of
concern raised by neighbors that these dams were backing up water onto their property,
the dams were periodically monitored and removed. The dates that the dams were
knocked down can be observed in the hydrographs. It should be noted that in addition to
these dams, the level of the adjacent ditch that runs through the neighbors' property and
ties into the creek was observed. It was never noted to be unusually high or stagnant, even
during heavy rain events. However, the creek will continue to be monitored for the
reappearance of dams.
5

3.0 Vegetation
3.1 Success Criteria
The Rowel Branch Mitigation Plan states that the vegetation success criterion for
this project is the survival of 320 trees per acre, including acceptable volunteer species. In
addition, no individual hardwood species may account for more than 20% of the total
number of stems.
3.2 Methods
A list of the tree species that were planted in the spring of 2000 at the Rowel
Branch tract is given in Table 3. These one-year and two-year seedlings were obtained
from the NC Forest Service Nursery and were planted on a ten-foot spacing within the
floodplain of Rowel Branch. The vegetation survey consisted of establishing a circular plot
every 25 feet along two transects within the tract (Figure 5). The center of each plot was
marked with a pink pin flag and the ends of the transects were marked with orange
flagging. Each plot had a radius of 10 feet and an area of 314.2 ft2. Transect 1 contained
7.5 plots and transect 2 contained 6.5 plots. Therefore, the total area surveyed was 4398
ft2, or approximately 0.1 acre. Transect 1 was approximately 200 feet in length and began
along the edge of a planted area that was relatively high in elevation. Progressing along
the transect, elevation gradually dropped until the stream was encountered, which
represented the lowest elevation and wettest point along the Tansect. Then the elevation
rose again as it moved toward the stockpile area, where it ended. Transect 2 was
approximately 175 feet in length. No major changes in elevation were observed along this
transect except for a low ponded spot in the middle. The tansect began at the canal, near
where it turns 90 °, and ended at the stream.
6

Table 3. Number and types of trees planted at Rowel Branch on March 15 and April 1 of 2000.
Trees were planted at a density of 435/acre.
Common Name Scientific Name # Planted
Atlantic White Cedar (2 yr) Chamaecyparis thyoides 1000
Bald Cypress (1 yr) Taxodium distichum 1600
Green Ash (1 yr) Fraxinus pennsylvanica 800
Water Oak (1 yr) Quercus nigra 1000
Willow Oak (1 yr) Quercus phellos 1300
Yellow Poplar (1 yr) Driodendron tulipifera 600
TOTAL 6300
3.3 Results
For both transects, herbaceous vegetation observed within the drier areas included
Eupatorium capillifolium, E. hyssopifolium, and Rubus spp. In the wetter areas, Scirpus
cyperinus, Peltandra virginica, Mikania scandens, Juncus effusus, Polyganum
sagittatum, and several sedge species (Cyperus and Carex spp.) were observed. Overall,
more herbaceous vegetation was observed in transect 1 than in transect 2 (Appendix Q.
The planted trees that were observed within the transects were found to be in good
condition and most were taller than last year. Several bald cypress (Taxodium distichum)
trees were over 12 feet tall. Volunteer alder (Alnus serrulata) and black willow (Salix
nigra) seedlings were found in wetter spots, especially near the stream in transect 1. Most
of the red maple observed was in transect 2, where the herbaceous layer was not as thick
and sunlight was able to reach the ground. These red maple seedlings were typically 12-18
inches tall. It should be noted that fewer red maple seedlings were observed in 2002 than
in 2001.
7

Table 4. Number and species of trees surveved within two tran sects at Rnwel Rranrh (9/9/09)
Common Name Scientific Name Average Total # of # Counted
Height (in) Trees Towards
Observed Criteria
Alder Alnus serrulata 30.7 57 56.6
Atlantic White Cedar* Chamaecyparis thyoides 5
39.6 5
Bald Cypress* Taxodium distichum 54.3 41 41
Black Willow Salix nigra 52.6 18 18
Eastern Sycamore* Platanus occidentalis 33.0 4 4
Loblolly Pine Pinus taeda 25.0 7 7
Red Maple Acer rubrum 30.4 125 56.6
Sweetgum Liquidambar styraciua 27.8 11 11
Willow Oak* Quercus phellos 43.3 9 9
Winged Sumac Rhus copallina 21.0 6 6
TOTAL 283 214.2
(Data for the individual transects are given in Appendix D.)
*Species was planted in 2000.
A total of 283 trees was observed within the surveyed plots (Table 4). The
mitigation plan stated that no single tree species could represent more than 20% of the
total number of trees observed. After factoring in this requirement, the number of trees
that were counted towards the vegetation success criterion is 214.2 trees. The total
number of trees observed is slightly less than last year (315 trees). However, the number
of trees counted towards the success criteria is higher (205.6 trees vs. 214.2 trees). This is
mostly due to the higher number of red maples observed in 2001, which inflated the first
figure. Because the total area of all the plots represents approximately 0.1 acre, the
average number of trees/acre is 2142. This is more than 6.5 times the minimum 320
trees/acre required by the mitigation plan. Therefore, vegetation meets the success
criterion during year two monitoring.
8

4.0 Conclusions
ECOBANK has restored 16.1 acres of bottomland hardwood wetlands at the Rowel
Branch tract in Brunswick County, North Carolina as mitigation for unavoidable wetland impacts
associated with the construction of the Wilmington Bypass by the NCDOT. To restore this area,
fill was removed from the riverine floodplain, trees were planted within the floodplain, and a large
diversion canal was filled to restore hydrology to the stream. In the summer of 2002, a vegetation
and hydrology analysis was performed to evaluate year two conditions at this mitigation site.
Groundwater monitoring data collected from automated gauges during 2002 show Rowel
Branch to support wetland hydrology even during an abnormally dry year. As in 2001, all six of
the gauges on site showed groundwater levels at or within 12" of the soil surface for at least
12.5% of the growing season (33 days). Most gauges greatly surpassed this percentage. In
addition, data from the restoration gauges followed the patterns of the reference gauges.
An evaluation of the riverine success criterion determined the frequency and duration of
overbank flooding within the tract and within the reference site. None of the mitigation gauges
met the success criterion of establishing overbank flooding events at a frequency and duration
within 10% of the reference site. All three of the gauges located within the restored stream at
Rowel Branch (Al, B1, and Cl) experienced fewer flooding events and had shorter flooding
durations than the gauge located within the reference stream (RI). The cross-sections show that
the reference stream at its transect location is smaller in area than the restored stream at those
transect locations. Therefore, when comparing these points, the reference stream gauge floods
more frequently. The number of flooding events and average flood frequency documented by the
three gauges located 50' away from the restored stream (A2, B2, and C2) varied considerably
from the reference gauge (R2). Gauges A2 and C2 documented more frequent flooding than R2,
but with shorter average durations. Gauge B2 had fewer flooding events, but with much longer
average frequency. It should also be noted that the A and C transects experienced more frequent
flooding events 50' away from the stream than directly adjacent to the stream even though the
gauges 50' away from the stream were at higher elevations than the top of the bank. This may be
because the topography is flatter 50' away from the stream and short-term rainfall can create
ponding in these areas. Closer to the stream, slopes are greater and rainfall is transported at a fast
9

rate downstream, decreasing overbank flooding.
There are several reasons why the riverine success criterion was not achieved. First, the
reference stream is located in the middle of Leland Industrial Park and receives a large amount of
stormwater runoff from impervious cover associated with this development, which may cause
additional flooding. Property- surrounding Rowel Branch is mostly small residential units or
undeveloped parcels, which contribute less stormwater flow into the restored stream. In addition,
the dimensions of the restored stream were not based on those of the reference stream. The
unchannelized bottomland hardwood reference site was chosen as a general control for
groundwater hydrology. Site selection of the gauge placement was not based on similar cross-
sectional profile data between the reference and the restored sites. Therefore, overbank flooding
results are difficult to compare particularly when the four transects were selected at random with
no pre-project elevation information.
Just like most coastal streams, Rowel Branch's stream bank heights show great variability
and, therefore, overbank flooding events should not be referenced to one spot along an entire
stream gradient. Rack lines, fresh sediment buildup, and compressed herbaceous plant stems are
better indicators of flooding throughout the system. Further compounding the comparative results
of random monitoring points is the braided nature of the coastal floodplain. In one instance, the
reference gauge may be situated near a lower shelf braided branch of the main stream while the
restoration gauge may be on a higher position on the floodplain. It is important to look at the
entire system rather than at individual points. The requirement that all restored gauges must be
within 10% of one sample reference transect is too restrictive and does not account for the high
variability of the coastal bottomland hardwood stream system. A better solution would be to put
more importance on achieving survivability of similar hydrophytic plants and maintaining wetland
hydrology over the course of five years. Flooding events could be modeled with a design storm of
a certain event (i.e. 10, 25 or 50-year) and then compare the extent of flooding over the four
transects. In this manner one can project the flooding dissipation function of the floodplain in both
reference and restored sites in a manner similar to FEMA and stormwater/sediment control
models.
However, because the Rowel Branch gauges documented frequent flooding events and
10

because wetland vegetation is flourishing throughout the site, it is achieving its overall goal of
restoring a riverine floodplain system The riverine success criterion appears to be too restrictive
and may need to be redefined by the commenting agencies.
The vegetation analysis found a total of 283 trees within the surveyed plots. After
factoring in percentage requirements, the number of trees that can be counted towards the
vegetation success criterion is 214.2 trees, or 2142 trees/acre. This is more than 6.5 times the
minimum 320 trees/acre required by the mitigation plan and is an increase in number from
monitoring performed in 2001. Therefore, vegetation meets the success criterion during year two
monitoring.
Based on the data analysis within this report, the conclusion of the year two monitoring is
that the Rowel Branch tract has fulfilled the vegetation and hydrology success criteria established
in the mitigation plan and that the wetland restoration of the tract is thus far successful.
11
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Land Management Group, Inc. Rowel Branch Tract
Environmental Consultants Wilmington Bypass Project
Figure 1. Vicinity map.
Wilmington, N.C. Brunswick County, NC
November 2002 Year Two Monitoring Report
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Pa map Wilmington Bypass Project
Environmental Consultants
of site and reference area Brunswick County, NC
Leland Wilmington, N.C.
t Quad). November 2002 Year Two Monitoring Report
140
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LAND SURVEYORS ENGINEERS LAND PLANNERS
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Appendix A. Engineering Report performed by Wrightsville Engineering Services

DESIGN CONSIDERATIONS
for
ROWEL BRANCH TRACT
WETLAND RESTORATION PROJECT
MOUNT MISERY ROAD, LELAND
BRUNSWICK COUNTY, NORTH CAROLINA
PREPARED FOR
ECOBANK
1555 Howell Branch Road
Winter Park, Florida 32759
[phone]
June 2001
FILE NO.: 20003
? tc
SE "
141,0 ?
PREPARED BY
WRIGHTSVILLE ENGINEERING SERVICES
3410 Wrightsville Avenue
Wilmington, NC 28403
[phone]
R
1. INTRODUCTION
Wrightsville Engineering Services had been contacted by the office of Land
Management Group, Inc. to review the proposed channel design with respect to
potential- impacts to adjoining properties. We feel that there are two potential
design approaches: providing a minimum cross section to match that of the
existing design; or, providing a minimum cross section to meet estimated
hydraulic conditions. We will expand on both of these approaches from both a
base flow (normal flow) and peak flow rate review.
2. EXISTING CONDITIONS
a. Roadway Culvert I Base Flow Analysis
Base flow was defined as the normal stream flow during non-storm events.
Regarding meeting the existing design, it would appear that the base flow
through the existing roadway culvert gives an easily identifiable cross section. At
the time of our site visit, the culvert had approximately 3.0 feet of standing water
within the 7-foot CMP culvert. Estimation of velocity was approximately 0.25 fps.
For our calculations, we have doubled the velocity which, in turn, gives a safety
factor into the design. With these elements, we estimate the base flow cross-
sectional area (that below the water surface) to be 15.75 square feet (SF) with an
estimated flow of 7.9 cubic feet per second (CFS) (15.75 SF .x 0.5 FPS).
Analysis of a major storm event was made using TR-20 hydrology software with
the 25-year, 24-hour storm event. Review of the existing roadway culvert
indicates the maximum possible flow rate before overtopping of the roadway to
be approximately 550 CFS. Performing a crude approximation of the upstream
watershed topography indicated that the actual flow rate would be closer to 360
CFS taking into account ponding of runoff within the natural terrain.
Calculations for this analysis have been included in the Appendix.
b. Existing Canal Analysis
The existing canal system consists of. a fairly well defined trapezoidal cross-
section which, over time, has sloughed in some areas. Review of a typical cross-
section yields a base flow cross-sectional area (that below the water surface) of
$5.6 SF and a maximum flow rate of 401 CFS before the banks are overtopped.
As backwater becomes more of an issue, the velocity of the base flow must be
reduced considerably conveying the same flow rate. The analysis performed on
these flows has been included in the Appendix.
3. PROPOSED IMPROVEMENTS
a. General
The proposed improvements consist of constructing a meandering channel
through the original low areas to match what had existing prior. Review of the
existing channel indicated that the width and depth varied considerably as one
might expect. Longitudinal slopes, by comparison to the existing channel, are
relatively similar even though the travel lengths vary. This is due to the fact that
little elevation change occurs across each of the travel paths.
lb. Peak Flow Rate
Vlfith respect to proposed design, the current cross section, without any further
improvements, appear to meet or exceed the roadway flood flow of 550 CFS.
Maximum flow rate was defined as that flow which can be handled without
exceeding the elevation of the existing canal sides. Sections taken
approximately 500 feet apart in the new channel, both upper and lower, yielded a
flood flow capacity of 55.8 and 14.20 CFS respectively. Therefore, the capacity of
the channel would exceed the current limiting factor (roadway culvert).
c. Base Flow Rate
Another consideration in the evaluation was review of the base flow. In order to
meet or exceed the limiting design element (existing culvert), we have
recommended using 'a minimum cross-sectional area of 20 SF below the water
line throughout the initial stages of the relocation. This should minimize concerns
regarding possible claims of providing a bottleneck by the project. Actual design
flow considerations indicate that a more realistic cross-section of either a 6' wide
by 2' deep channel or an 8' wide.by 1.5' wide channel would be adequate to
convey the base flow without any increase in the water surface upstream.
Preliminary review of the impacts of reducing the channel to T wide by 1.5' deep
would yield a rise in water elevation of 0.7 inches for each 500 feet of relocated
channel. Similarly, a channel section of 6' wide by 1.0 foot deep would yield a
rise in water elevation of 5" for each 500 feet of relocated channel.
4. CONCLUSION
These results are based on very limited data but they do yield some usable
results. Determination that the roadway culvert appears to be the limiting factor
in the design and that the proposed channel peak flow rate will exceed that of the
current design. Also, the recommended channel cross-section of 20 SF to meet
current design would appear more than adequate for the initial areas; whereas, a
section of 12 SF would appear to be more in line based on actual flow rates at
4
he time of our field visit.

Data for Rowell Page 6
TYPE II 24-HOUR RAINFALL= 8.00 IN
Prepared by Wrightsville Engineering Services 25 Jun 01
HydroCAD 5.11 001707 (c) 1986-1999 Applied Microcomputer Systems
SUBCATCHMENT 1 Upstream Drainage Basin
PEAK= 716.1 CFS @ 15.22 HRS, VOLUME=271.20 AF
ACRES CN SCS TR-20 METHOD
1074.00 65 Class B, 2 acre residential TYPE II 24-HOUR
RAINFALL= 8.00 IN
SPAN= 10-20 HRS, dt=.1 HRS
Method Comment Tc (min)
CURVE NUMBER (LAG) METHOD Segment ID: 259.1
L=5280' s=.005 '/'
SUBCATCHMENT 1. RUNOFF
Upstream Dr-ca i nc,geB Bas i n
700
650
600
550
500
450
U 400
`-? 350
300
a 250
LL_ 208
ISO
109
50"
9m -
AREA= 1074 AC
T== 259.1 MIN
CN= 65
S TR-20 METHOD
T E ZI 24-HOUR
RRINF L= 8.00 IN
PEAK= 1 CF5
15. HRS
UOLUME= 271.-2
N M C- LO m Ol
TIME C}-hoLAr-r.)

Data for Rowell Page 7
TYPE II 24-HOUR RAINFALL= 8.00 IN
Prepared by Wrightsville Engineering Services 25 Jun 01
HydroCAD 5.11 001707 (c) 1986-1999 Applied Microcomputer Systems
POND I
Roadway Grossing
Qin = 737.1 CFS @ 15.22 HRS, VOLUME=288.73 AF,- INCL. BASE FLOW= 21 CFS
Qout= 362.4 CFS @ 18.15 HRS, VOLUME=171.07 AF, ATTEN= 51%, LAG= 175.8 MIN
ELEVATION AREA INC.STOR CUM.STOR
(FT) (AC) (AF) (AF)
17.5 1.00 0.00 0.00
18.0 1.50 .63 .63
20.0 5.00 6.50 7.13
22.0 10.00- 15.00 22.13
24.0 20.00 30.00 52.13
26.0 40.00 60.00 112.13
28.0 80.00 120.00 232.13
29.8 150.00 207.00 439.13
STOR-IND METHOD
PEAK STORAGE =
PEAK ELEVATION=
FLOOD ELEVATION=
START ELEVATION=
SPAN= 10-20 HRS,
Tdet= 142.6 MIN
128.91 AF
26.3 FT
29.8 FT
17.5 FT
dt=.1 HRS
(171.07 AF)
# ROUTE INVERT OUTLET DEVICES
1 P 17.5' 84" CULVERT
n=.021 L=76' S=.0012'/' Ke=.2 Cc=.9 Cd=.75 TW=20.9'
POND 1 DISCHARGE
Rocadwcay Crass i ng

rt ?

Z 24.5 -
'
j
W
_
L
r
L
=>
J 20.5 - ??
LLJ
1 9 . 5
IB.S
17.5- - 611" CUL-UERT
m m m m m m co m m m
m LS') m N m ? m C ? It
DISCHARGE Ccf s?
POND 1 INFLOW & OUTFLOW
Roadway Crossing
708
650 STOR-=ND METHOD
600 ASE FLOW= 21 CFS

550 PEA STOR= 12B.9t AF
PE ELEU= 26.3 FT
.. 500
450 n= 737, CFS
u 400 Qou - 362.4 CF=` MAX
ZZ5 R -LIiIN 7
"'
O 30H ? ?
\
20e
15B i?
1 00 i'
50 /

Ln ?D rl- co Ql p

TIME Chour-a
Existing - Section 1
Worksheet for Irregular Channel
Project Description
Project File d:lprojfile12000fi-1120003--11ditches.fm2
Worksheet Row-ex1
Flow Element Irregular Channel
Method Manning`s Formula
Solve For Discharge
Input Data
Channel Slope 0.02%
Water Surface Elevation 20.90 ft
Elevation range: 17.73 ft to 28.42 ft
Station (ft) Elevation (ft) Start Station End Station Roughness
0.00 28.42 0.00 200.00 0.024
37.00 28.14
77.00 27.60
123.00 26.97
132.00 19.78
140.00 17.73
147.00 19.75
169.00 25.50
200.00 26.77
Results
Wtd. Mannings Coefficient 0.024
Discharge 43.10 fts/s
Flow Area 35.60 ft. cYZ or"s- SE C-Tko+.JfAL.
Wetted Perimeter 21.89 ft
Top Width 20.80 ft
Depth 3.17 ft
Critical Water Elev. 19.26 ft
Critical Slope 0.009615 ft1ff
Velocity 1.21 ft/s
Velocity Head 0.02 ft
Speck Energy 20.92 ft
Froude Number 0.16
Full Flow Capacity 709.84 ft3/s
Flow is subcritical:
Jun 26, 2009 Klein Engineering and Associates FlowMaster v4.1 c
11:0436 Haestad Methods, Inc_ 37 Brookside Road Waterbury, CT 06708 [phone] Page 1 of 1
? xL SZ'tNC:?

Existing - Sta 1
Cross Section for Irregular Channel
Project Description
Project File d:\projfiie\2000F-4\20003=-1\ditches.fm2
Worksheet Row-exl
Flow Element Irregular Channel
"MiAhbd Manning's Foot iul i
Solve For Discharge
Section Data
Wtd. Mannings Coefficient 0.024
Channel Slope 0.02 %
Water Surface Elevation 25.50 ft
Discharge 401.30 fF/s ?---- M>4X • ?t-ow ??
30.0
28.0
26.C
i 24.C
C
0
22. C
LU.
20.C
i B.C
Jun 25, 2001
07:35:07
46.
0.0
4
1
J SY+ tc- ?46-, 111 A*
C,
}
S?U•?
?w R•ti2.?
ST?2E ? c?2.
Yl ? PS'E.ti
LEV.
Z5.5
?

d

0
20.0 40.0 60.0 80.0 100.0 120.0 140.0 i 60.0 180.0 200.0
Station (it)
Klein Engineering and Associates FlowMaster v4.1 c
Haestad Methods. Inc. 37 Brookside Road Waterburv, CT 06708 ,2= 755 1666 Paoe i of 1

New Ditch - Upper
Cross Section for Irregular Channel
Project Description
Project File d:lprojfiie12000fi--1120003--1\ditches.fm2
Worksheet New Channel - Upper
Flow Element lrregula?r Channel
Method Manning's Formula
Solve For Discharge
Section Data
Md. Mannings Coefficient 0.030
Channel Slope 0,02 %
Water Surface Elevation 25.50 ft
Discharge 557.76 T/s woo LAS

C
0
ca
5
m
[!1
Jun 25, 2001 i Jein Engineering and Associates FlowMaster v4-1 c
07:48:42 Haestad Methods, Inc. 37 Brookside Road 1Naterbury, CT 06708 [phone] Page 1 of 1

0.0 50.0 100.0 150.0 200.0 250.0 300.0 350.0 400.0
Station (ft)
Proposed - lower
Cross Section for Irregular Channel
Project Description
Project File d:\projfie\2000ft-1120003-1\ditches.fm2
Worksheet New Channel - Lower
Flow Element Irregular Channel
Method Manning`s Formula
Solve For Discharge

Section Data
Wtd. Mannings Coefficient 0,030
Channel Slope 0.020%
Water Surface Elevation 25.50 ft
Discharge 1.420.55 fills - 50 cp>-
27.0
26.C
25.C
24.C
23.C
C
0
w
> 22. C
W
Jun 25, 2001
07:53:18
21.(
20.(
19.(
18.0 L--
0.0
50.0 100.0 150.0 200.0 250.0 300.0
Station (ft)
Klein Engineering and Associates FlowMaster v4.1c
Haestad Methods, Inc. 37 3rookside Road Waterbury, C706708 [phone] Page 1 of t
TIR C)?oc??
8'x 1.5' Ditch
Cross Section for Rectangular Channel
Project Description
Project File untitled
Worksheet New Ditch Calcs
Flow Element Rectangular Channel
Method Manning's Formula
Solve For Channel Slope
Section Data
Mannings Coefficient 0.030
Channel Slope 0.016 % }-? r'ZKE t tJ WATE.SP- ELP-V .
Depth 1.50 ft
Bottom Width 8.00 ft
Discharge 7.90 ft3ts ?--- $ASt o?-J
1.50 ft
8.00 ft
1?
V
H 1
NTS
Jun 26, 2001 Klein Engineering and Associates FlowMaster v4.1c
10:18:24 Haestad Methods, Inc- 37 Brookside Road Waterbury, CT 06708 (203) 7555-1666 Page 1 of 1
1?owNSTR EAc?'l
6' x 2' Ditch
Cross Section for Rectangular Channel
Project Description
Project File untitled
Worksheet New Ditch Calcs
Flow Element Rectangular Channel
Method ' Manning's Formula
Solve For Channel Slope
Section Data
Mannings Coefficient 0.030
Channel Slope 0.014 % < p -07-/a NO ;U--,E tN W AT Ev-- ELr=V •
Depth 2.00 ft
Bottom Width 6.00 ft
Discharge 7.90 ftNs -?-- BASS Fr_.o"J
77
2.00 ft
6.00 ft
V N
H 1
NTS
Jun 26, 2001 Klein Engineering and Associates FlowMaster v4.1c
10:16:57 Haestad Methods, Inc. 37 Brookside Read Waterbury, CT OMB [phone] Page 1 of 1
??. cUt`?ST42i=14t`?
Figure B.1. Hydrology Monitoring, Gauges Al & A2
Rowel Branch Tract: Restoration
42
36
30
24
.s
18
A 12
g 6
D
-6
12
-18
-24
----------------------- -------------------------------------------
-------------------------------------------------------------------
----------- ---------------------
------------
---------- ,? ------------- ---------------------I --- - -- --- ----------
r.'..----?- - `may ?--------------------- - - ---------
----- L-1
O1 O~ O1 O1 O~ O~ O1 O1 O1 O1 O~ O~ O1 O1 O1 O~ O1 O~
bhp q?J` 1,J` PJ4i QJ? PJQ' eJ? PJ? ?s4Q p?4Q 1SGQ ?S°?
pti q? 1h' ryti rya O 1 ry ry q9' 10' 1Y r,¢ ?~ O 1 ry ry
-?-AI (S353B9B) -kA2(S353A32) -12"below surfacelRainfall
Rainfall information provided by the National Climatic
Data Center: Wilmington international Airport station. Note: 1 reading/day
42
36
30
24
$ 18
Ca 12
w
3 6
0
-6
-12
-18
-24
Figure B.1 contd. Hydrology Monitoring; Gauges AI & A2
Rowel Branch Tract-, Restoration
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
.--------------------------------------- - -------------------------
----------- - ------------------------------------------------------
--------.'---------------------------------------------------- - - --
---------------------- --------------------------------------------
Ift
---------------
---------------------------------- ------- -
10
8
6
0
4 5.
2
0
to
8
6
w
4 5.
2
0
O1 O1 O1 O1 O1 Q1 O1 O1 O1 O1 Al O1 01 O1 Off' Off' 01' Off'
O°1 O' O' O?
01 p?' 15' ryti ryq' Oy 1'Y 1°i' ryb O"r' 1Cf ?1' ryd ,y1.' p1 ?b ry1 ry6
b At <S353B9B> 4c A2 <S353A32> ¦Rainfall (in) -12" below surface
Rainfall information provided by the National Climatic
Data Cents Wilmington International Airport station. Note. 1 ieadiuefday

Figure B.1 contd. Hydrology Monitoring, Gauges Al &A2
Rowel Branch Tract; Restoration
42 10
36 --------------------- ------ -------------------- ---------
beaver dam removed
30 ---- y--??a+------------- ------- 8
24 - - -,'erewcw -
5
18 -- - -------------------------------------------------------------
6 Q 12 --------------------------------------------------- - ----------
d
v
a 0
-6 ------------------------------------------- - -------------'< 2
-12
-18 ----------- ----- ------------------------------- -----------
-24 0
01' OR' ' O.1' 01' Off' ?1?' 01' OR' Off' 01' Off' 01' Off' 01' 01' Off' OR' n, g?
01' O? \5 titi 01 O? \5 tiry Iy°t OS" \`L \O ryb Ong \p \1• • y ^1'
-a Al <S353B9B> * A2 <S353A32> SRainfall (in) -12" below surface
Rainfall information provided by the National Climatic
Data Center; Wilmington International Airport station. Note: I readingiday
Figure B.l contd. Hydrology Monitoring. Gauges Al & A2
Rowel Branch Tract; Restoration
42
36
30
24
.5
18
w
Q 12
3 6
0 0
-6
-12
-18
24
------------------------------------------------------------ ------
---------------------
a
------------------------ -beat' r
--------------------------------------' -
---------------------------
-----
* -- ---
- ----- ------------- -----
10
dam removed
8
6
4 5.
2
0
01' 01' Off' Off' 01' O'ff' Off' 01' Off' OR' Off' OR' Off' 01' O'1'
?q O$ Oda JC vC 4
-AI <S353B9B> *A2 <S353A32> MRainfall (in) -12" below surface
Rainfall information provided by the National Climatic Note: 1 readirra?doy
Data Center, Wilmington International Airport station.
a
Figure B.2. Hydrology Monitoring, Gauges BI & B2
Rowel Branch Tract_ Restoration
42
36
30
24
18
d
Q 12
3 6
b
0
-6
-12
-18
-24
10
8
6
w
w
4 5.
2
0
01' Off' O1' O~ O? O? O? O~ O1 01 01 Ol 01
Ory' 1A ryti •y6 ?' 11 .`0 ryh Ory 09' tib .1,'9 n?O
b-B] (S213EB6)A-B2 (5369807) -12" from surface IeRainfall
Rainfall information provided by the State Climate Cffce
of North Carolina at North Carolina State University; Note: 1 readiogiday
Wilmington International Airportstation.
Figure B.2 contd. Hydrology Monitoring, Gauges B1 & B2
Rowel Branch Tract; Restoration
42
36
30
24
is
d
Q 12
m 6
c
0 0
r5
-6
-12
-18
-24
'---------- ------------------------- ------------------------------
---- -------------------------------------------------------
-- - -----------------
----- o-' ` ------------------------------------------------------------
------------------- ----------- --------------------q?------ A
------------------ - -- ------------------------------------------- - ----
- -------------
------------
---------------
o-
-------------
A
- - --------------------------------
?IAA i`i
------------------- ---------------------
--- 0?- ?? ------------------- ] ------------------------------

O? O~ O? Off' 01 O? O? O? O~ O? O?
O\ 04' 15 ,y`l% ryq O(i tih .10• .11' O,h,P 1O.F'
o-BI (S213EB6) -A-B2(S369807) -12"@omsurface?Rainfall
Rainfall rfermafiar provided by the National Climatic
Data Center; Wilmington international Airport station. Nole: 1 readingday
1 6.
42
36
30
24
.S
$ 18
q
12
d
3 6
0 0
6
-6
-12
-18
-24
Figure B.2 contd. Hydrology Monitoring, Gauges B1 & B2
Rowel Branch Tract; Restoration
1
Off' Off' 01' OR' OZ' 01' 01' OR' Off'
4`ro 4° 4`ro 4` 4? 4? 4`? 4` 4?
O°I? 1? 1? 15? '?^ 1q 'L? rY? rYb
1-131 (S210DA5) -12 from surface -Rainfall
Rainfall information provided by the National Climatic
Data Center, Wilmington international Airport station.
10
8
6
ro
4 5
2
0
Now 1 rmdbtgrday
Figure B.2 contd. Hydrology Monitoring, Gauges B1 & B2
Rowel Branch Tract; Restoration
42
36
30
24
18
w
12
3 6
b
0
.6
-12
-I8
-24
10
8
6 m
4
2
0
Off' Off' & Off' & Off' Off' & Off' Off' Off' 03'
01' 1K ti~ r1O 05 ti'L 19 rob 01% Oq. 1b rti'S' „O Ob
-BI (S210DA5) I,-B2 (S44877B) -12" from surface SRainfall
Rainfall information provided by the National Climatic
Data Center, Wilmington International Airport station.. Note: 1 r.dingrday
----------------------------------------------------------
----------------------------------------------------------
1
I --
--------------------------- -- - - - /q'?---------------
???° ?a "o? ° o^?ooa?voaoooe?
°-? -o.aO"
------0"2.oeo" - -- - - - - - --------------------
---------------s-----
1 ?_? ?---_- L? ®? a ® J- 1A-.---
y
42
36
30
24
.6
$ 18
a
A 12
d
3 6
v
5 0
-6
-12
-18
-24
Figure B.3. Hydrology Monitoring, Gauges C I & C2
Rowel Branch Tract; Restoration
----------------------------------------------- ------------------
------------------------------------------------------------------ - ----
------------------------------------------------------------------------
------ -
----------------------------------------------- - ---------------------
-------------------' -------------------- --- -- ----- ¢ -------------
d ?
.
"---------------a-----0'--------A---------III, ------ W-1111 ---------------
01 t~ 1?1 Off' ON 1?1 lz?, O` O~ O~ O?, A? O~ O,
JJ Jr J9 ?? ?J~ ?? ?J? J? J? Ja' J? J? t4 e4 e4 e4
O,'JJ OR'sJJ
tih? ryry? ry?;s Ob '?^? ryO `11 O,?.R' ,OQ' ,1 Q' ,?•Q' '+1e' OHO tip, 'y?? `YQ,?
-CI (5353979) C2 (S126F6B) -12" below surface ®Rainfall
Rainfall information provided by the National Climatic
Data Center. Wilmington intonational Avpart station. Note: I readinglday
42
36
30
24
,s l8
A 12
3 6
a
0
-6
-12
-18
24
Figure B.3 contd. Hydrology Monitoring, Gauges C 1 & C2
Rowel Branch Tract: Restoration
k_____________________________?- ___?.__ o____ - ?,_____-._11-__
4____________________________________________________t_____________-
Sb
10
8
6 1
5'
w
S'
4
2
0
01' O~ O? 01 01' O1 O~ O~ O? A~ O~ O, Oti O? 01' Off' Off' Off'
o?Cc?o??`^'tiSCL`r'LtiOCN`IQOL`' S?c41'1+?o-rAryoaO"?9c°tiO9o`c`°'y19c` O^,ac
>Cl (S353979) G C2 (SI26F6B) -12" below surface MRainfall (in)
Rainfall irdornatien provided by the National Climatic
Data Center; Wilmington International Airport station. Note: 1 readmgday
42
36
30
24
.5
18
a
Q 12
d
3 6
0 0
-6
-12
-18
-24
Figure B.3 contd. Hydrology Monitoring, Gauges C I & C2
Rowel Branch Tract; Restoration
'-------------------------------------------'------'----------- ---
- ----------
-------------------------------------------------------------------
----'
---------------------------------- ---------------------------------
--------------------------------------------------------------------
ey g a
I ?aq
-A
- ; to - ?° ? - F ay a?
10
8
6
4 5.
2
0
Ory' & & & & P? Qry Off' & 19 & & Off' %9 Off' & Off' &
o,? O?• ,t?• ry.1; p1. Og ,r-r, ryti ryq? OS' 11' .lq• ry6 p„?. ,p? ?^. _p` ?y1
-C I (5353979) A C2 (S 126F6B) --12" below surface ®Rainfall (in) p
Rainfall irformation provided by theNatitmal Climatic
Data Center; Wilmington International Airport station. Note I rcadineday
42
36
30
24
d
U
.5 18
v 12
m 6
3
v
0
o
0
-6
-12
-18
-24
10
8
6
m
w
4
2
0
01' Off' Off' OR' Off' 01' Off' Off' Orl' OR' Off' ?' Off' Ory' 01'
???$ ??? ?.,?? O?? Ob?3 ?q?O? ry?,? ry^SO? ?F°? bCO? `Co^S
0 ti ry ry p ? p," ` ,\ -
, ry q
o
?C I (5353979) t C2 (S 126F6B) -12" below surface !Rainfall (in)
Rainfall information provided by the National Climatic
Data Center, Wilmington International Airport station. Note: I readingday
Figure B.3 contd. Hydrology Monitoring, Gauges C 1 & C2
Rowel Branch Tract_ Restoration
----------- --- --- ------- --------------------
I - - ---
1 1 ._ ?® -------- 1 0 l 1 e
Figure B.4. Hydrology Monitoring, Gauges R1 & R2
Rowel Branch Tract; Reference
42
36
30
24
S
18
a
A 12
d
3 6
0
c7
-6
-12
-18
-24
-------------------------------------1------------------------------
------------ - -----------------------1 --- -- ---- ?- -------------
-------- -------- tr - - -
`- - a - x ,
?l
i -iq-h llcka ?fit?kk
8
6
4 _
5'
2
0
O~ 01 O,' O? O~ O~ Off' 3, Off' O~ O~ O, S' O~ O~ O? O' O?
??o ?,c 1? ,10 ?0o ?3 53 ??v 1? o? a? J? o? uV ScQ Sc4 5c4 5c4
Oti 00 .?S' .y'V ti0 Ob lnr• .10 'L1 On.Q' ??Q' 1,?.F` ?F' ?lC' O^ 1l*' ry> ,yQi
?Rl (S126F2F) * R2 (S3539A7) -12" below surface ®Rainfall
Rainfall information provided by the National Climatic
Data Center, Wilmington International Airport station. NMe: 1 read'utgtday
Figure B.4 contd. Hydrology Monitoring; Gauges R 1 & R2
Rowel Branch Tract, Reference
42
36
30
24
.S
l8
a
A 12
3 6
0 0
c7
-6
-12
-18
-24
10
8
6 =
4 S
2
0
O? O? O~ O1 O, s, O, O~ &, O~ 01 O? O~ O? & & Off' Off'
O,Oca,O?O 1SO?'L?•0 lrll4111+0 ??'$o ti°i?ca•yb?oaOS?cc?O?tol??cu`lp9c •y??cc O^'?p ?p',op11,QO??,?o
?-R) (SI26F2F) 4. R2 (S3539A7) --12" below surface ®Ra nfall
Rainfall infarmatim provided by the Nationat Climatic
Data Center: Wilmington Intonational Airport station. Nore: 1 reudin¢Jay'
------------'------ - ------------ ---------------------------------
---------------
------------------------------ %------- - ? y _
------------- -----------------------
r---------------
kkh-
Figure BA contd. Hydrology Monitoring, Gauges R I & R2
Rowel Branch Tract; Reference
42
36
30
24
.5
r 18
A 12
3 6
0 0
-6
-12
-18
-24
-------------------- '---------------------------------------------
---------------------------------------------------------- '
- - - - - - - - - - - - - - - - - - - - - - - - - --------------------------------------
e -
-- --
-° - -------------------------
----------------- - ------- ---------------------- ---------
-- --------- ----- ------------------------------ -----------
-
01' OR' Off' 01' 01' SJ?' OR' Off' 01' O1' 01' 01' 01' 01' OR' O'1' 01' Off'
44' 44' 4? 4G fie`' ??? ?? ?? ,?? apt e4` e?` e?` ???' ??? ??°?' ?°?' ?a?
o? o? ?5" titi of o? ?5' tiff rye' o`? ?ti ?°?" ryb" o'?' ?O' ??' tia ?,?
10
8
6
4 5.
2
0
-a RI (S126F2F) *-R2(S3539A7) -12" below surface eRainfall
Rainfall inrormatim provided by IhoNatimal Climatic
Data Cmtc, VAlmitglm Intonational Airport station. Nae: I reading-'6y
Figure B.4 contd. Hydrology Monitoring, Gauges RI & R2
Rowel Branch Tract; Reference
42
36
30
24
.s
r,,. 18
m
A 12
3 6
v
0
-6
-12
-18
24
-------------------------------------------------------------------
------------------------------- - - ------- - ------------------ - ---
R.
----------------------------------------------- -
----------------------- I-r
-j------------- '?7kT. % A? ----
----------------------- - ?-?-------------- ?i ? -
l0
8
6 m.
4
2
0
oh' & oti oti Oti oti oti oti oti ory oti oti oti oti oti oti & oti oti
?S? ??? ??? ??? ??3'??0~,,?;So?ryo?°?ry,???~ ?o?oQo?^e???Qo??Qo?^SCQ 0.04 ??c4 ?ScQ ?pov
SRI(S126F2F) *R2(S3539A7) --12"belowsurface Rainfall
Rainfall infatuation provided by thcNatimal Climatic
Data Center, Wilmingtm international Airport station. Noe 1 r.dimg'd.y
Figure B.5. Normal Rainfall Distribution
Wilmington International Airport
2001
12
io ------------------------------------------- -------------------------------
a ------------------------------------ ' -----------------------------
6 ----------------------------- --------- --- --------- ----------------
z
4 ------ ----------- f--- ?- - -- -------------- - --
_'^ ---_?
c+?e
0
O? O, O1' O, O~ O~ O~ O? O? O? 01 O~ O,
4v Soo pGN oip' ,Sao' Grp cr
rye' 11' O? ' p
®rainfall b-30-day running total -25th percentile -75th percentile
Based on 50.ycar data.
Rainfall ido oration provided by the National Climatic Data Center; 30th %calculated from precipitation probabilities based on
Wilmington Intematimal Airport station. gamma distribution at 76 North Carolina locations.
Figure B.5. Normal Rainfall Distribution
Wilmington Intemational Airport
2002
12
10 __________________________________________________________ ______ ______-
Q
I JJ??
6 --------------------------------------- ---- -------- --?-----------------d
2?? - ------ ---- -
-----
4
0
Off' 01' & Ory Off' Sl1 o, 01' Z1' Off' Off' 01' Off' 01' 01' 01' 01' Off' Off' 01'
O??o°lq?m° y??o°114c ?b4e0`ryct'etrybcte;O?FgS??PQO111a??o9'??3????Ory?°?lb?o?41??Q°K1QoK?gc4ryp5o4
rainfall 430-day running total -25th percentile -75th percentile
Based an 50 year data.
Rainfall information provided by the National Climatic Data Center; 30th %calculated from precipitation probabilities based on
Wilmington Intemational Airport station. gamma distribution at 76 North Carolina locatiams.
Pictures of site.
Land Management Group, Inc.
Environmental Consultants
Wilmington; N.C.
November 2002
Rowel Branch Tract
Wilmington Bypass Project
Brunswick County, NC
Year Two Monitoring Report
i Reference stream showing gauge located in stream.
? Reference area 50' from the stream.
Bald cypress growing within transect 41.
Land Management Group, Inc.
Pictures of site. Environmental Consultants
.
' ilminaton. N.C.
November 2002
Rowel Branch Tract
Wilmington Bypass Project
Brunswick County, NC
Year Two Monitoring Report
Vegetation growing along stream at bowel Branch.
Pictures of site.
Land Management Group, Inc.
Environmental Consultants
Wilmington. N C.
?.November 20,92
Rowel Branch Tract
Wilmington Bypass Project
Brunswick County, NC
Year Two Monitoring Report
Vegetation monitoring within transect #2.
? Vegetation near transect #2.
T.M. 1 RT,,,I% anA tcmP nftraac nhePrvPti in Trancect 1
Common Name Scientific Name Avera(enHeight # Observed
Atlantic White Cedar Chamaecyparis thyoides 36.6 5
Bald Cypress Taxodium distichum 52.2 27
Black Willow Salix nigra 52.6 18
Common Alder Alnus serrulata 36.5 21
Loblolly Pine Pinus taeda 26.0 5
Red Maple Acer rubrum 27.8 23
Sweetgum Liquidambar styraciua 27.8 11
Willow Oak Quercus phellos 43.3 9
Winged Sumac Rhus copallina 21.0 6
TOTAL 125
T?1,1P Ah,mhar and tvnP of trees nhcerved in Transect 2.
Common Name Scientific Name Avera(enHeight # Observed
Bald Cypress Taxodium distichum 56.4 14
Common Alder Alnus serrulata 24.9 36
Loblolly Pine Pinus taeda 24.0 2
Red Maple Acer rubrum 33.0 102
Sycamore Platanus occidentalis 33.0 4
TOTAL 158