2021-11-10 Minutes
November 10, 2021
-
Year 8
2
2021)
-
2021)
-
2021)
-
ay 2021
M
2021)
-
–
Survey TransectsSurvey EquipmentShoreline ChangeVolume ChangeStorm ActivityMaintenance ActivityShoreline & Volume Change (2020 Inlet Conditions (2020 Background Erosion Rates (2005/2006
Nourishment Triggers (2014
Data CollectionProject MethodologyKey Events: March 2020 Summary of FindingsQ&A/Discussion
Presentation Outline
3
2021)
-
2021)
-
2021)
-
ay 2021
M
2021)
-
–
Survey TransectsSurvey EquipmentShoreline ChangeVolume ChangeStorm ActivityMaintenance ActivityShoreline & Volume Change (2020 Inlet Conditions (2020 Background Erosion Rates (2005/2006
Nourishment Triggers (2014
Data CollectionProject MethodologyKey Events: March 2020 Summary of FindingsQ&A/Discussion
Presentation Outline
4
cing)cing)
cing)
2021
2021
2021
7,
spaspa
7, 2021
spa
-
-
ftft
15,
ft
2021
15,
2021
-
-
cing)cing)cing)cing)
15,
Survey Transects
15,
-
-
spaspaspaspa
–
ftftftft
14 Profiles (~500 and 1000 29 Profiles (~ 1000 22 Profiles (~ 2000 10 Profiles (~ 1000 23 Profiles (~ 500 and 1000 21 Profiles (~ 500 and 1000 19 Profiles (~ 1000
•••••••
Mason Inlet Relocation Project: May 2021 (GBA)Wrightsville Beach: January 5 Masonboro Island: January 6 Freeman Park: January 13 Carolina Beach: January 13 Kure Beach: January 13 Fort
Fisher: January 13
2021 Survey Dates:Surveyed Early to Aid in Development of 2022 CSDR Plans
Data Collection
5
Survey Transects
–
Survey Reach Landmarks:
Data Collection
6
Survey Transects
eaches
R
–
-
Survey Transects & Sub
Data Collection
7
Survey Transects
eaches
R
–
-
Survey Transects & Sub
Data Collection
8
Survey Transects
eaches
R
–
-
Survey Transects & Sub
Data Collection
9
Survey Transects
eaches
R
–
-
Survey Transects & Sub
Data Collection
10
–TOPO DATA
ATV AQUISITION
Survey Equipment
–
HYDRO
–
Survey Performed By Geodynamics
RV ECHO DATA AQUISITION
Data Collection
11
2021)
-
2021)
-
2021)
-
ay 2021
M
2021)
-
–
Survey TransectsSurvey EquipmentShoreline ChangeVolume ChangeStorm ActivityMaintenance ActivityShoreline & Volume Change (2020 Inlet Conditions (2020 Background Erosion Rates (2005/2006
Nourishment Triggers (2014
Data CollectionProject MethodologyKey Events: March 2020 Summary of FindingsQ&A/Discussion
Presentation Outline
12
AVD88
Shoreline Change
N
ft
–
AVD88
N
ft
Elevation (ft NAVD88)
Mean High Water (MHW) = +1.4 Recreational Berm = +5.0
Project Methodology
13
Volume Change
–
uter Bar
MHW
O
Depth Of Closure (Upper Bracket)Depth Of Closure (Lower Bracket)
–
Wading Depth
–––
–
AVD88
AVD88 AVD88
AVD88
20 ftN
4 ftN14 ft NAVD88 30 ftN
+1.4 ftN----Calculating Annual Volume ChangesCalculating/Updating Background Erosion Rates
Calculate Volume Above Multiple Elevations:Use Volumes For:
Project Methodology
14
Volume Change
–
ft
14
Volume
NAVD88
Example
Above -
Elevation (ft NAVD88)
Volume Calculation Lenses
Project Methodology
15
2021)
-
2021)
-
2021)
-
ay 2021
M
2021)
-
–
Survey TransectsSurvey EquipmentShoreline ChangeVolume ChangeStorm ActivityMaintenance ActivityShoreline & Volume Change (2020 Inlet Conditions (2020 Background Erosion Rates (2005/2006
Nourishment Triggers (2014
Data CollectionProject MethodologyKey Events: March 2020 Summary of FindingsQ&A/Discussion
Presentation Outline
5/25/2021 0:00
16
5/15/2021 0:00
5/5/2021 0:00
4/25/2021 0:00
4/15/2021 0:00
4/5/2021 0:00
3/26/2021 0:00
3/16/2021 0:00
3/6/2021 0:00
2/24/2021 0:00
2/14/2021 0:00
2/4/2021 0:00
1/25/2021 0:00
1/15/2021 0:00
1/5/2021 0:00
12/26/2020 0:00
12/16/2020 0:00
12/6/2020 0:00
11/26/2020 0:00
11/16/2020 0:00
11/6/2020 0:00
10/27/2020 0:00
10/17/2020 0:00
10/7/2020 0:00
9/27/2020 0:00
9/17/2020 0:00
9/7/2020 0:00
8/28/2020 0:00
8/18/2020 0:00
8/8/2020 0:00
7/29/2020 0:00
7/19/2020 0:00
7/9/2020 0:00
6/29/2020 0:00
6/19/2020 0:00
6/9/2020 0:00
5/30/2020 0:00
5/20/2020 0:00
5/10/2020 0:00
4/30/2020 0:00
4/20/2020 0:00
4/10/2020 0:00
3/31/2020 0:00
3/21/2020 0:00
3/11/2020 0:00
2021: Storm Activity
Significant Wave Height (ft)
-
–
airly Quiescent
ffshore Wave Heights
ffshore Wave Heights ffshore Wave Heights
ugust 2020
2021 Fairly Active
2 Events With Elevated OOver 2m (6.56 ft)
6 Events With Elevated OOver 2m (6.56 ft)Hurricane Isaias A8 Events With Elevated OOver 2m (6.56 ft)
airly Active
Spring & Summer 2020 FFall 2020 & Early Winter 2020/Late Winter 2021 & Spring 2021 F
Key Events 2020
17
20 : Approximately 824,216
-
(2020 = 25,312 cy, 2021 = 16,580 cy)
6.5 & 10
arch 2018
-
M
arch 2019
–
M
–
pril 2019
A
-
KB Transects 1
2021: Maintenance Activity
-
23 &
17: Approximately 763,000 cy
Approximately 1,057,267 cy-
Approximately 414,118 cy
14:20:16/
--
-
19: Approximately 41,892 cy
-
Transects 3 Transects 1 CB Transects 21 cyTransects 8
•••
•
Transects 18
Mason Inlet Relocation Project: March 2020Carolina Beach CSDR: February Kure Beach CSDR: March Wrightsville Beach CSDR: February
Carolina Beach Inlet Crossing: 2020 & 2021
Previous Projects:
Key Events 2020
18
2021)
-
2021)
-
2021)
-
ay 2021
M
2021)
-
–
Survey TransectsSurvey EquipmentShoreline ChangeVolume ChangeStorm ActivityMaintenance ActivityShoreline & Volume Change (2020 Inlet Conditions (2020 Background Erosion Rates (2005/2006
Nourishment Triggers (2014
Data CollectionProject MethodologyKey Events: March 2020 Summary of FindingsQ&A/Discussion
Presentation Outline
19
)
)
ft
)
+11.9 ft
+1.6 ft
–
–
*Survey Data Provided by the
Mason Inlet Relocation Project
131.3 ft
-
159.3 ft
-
Range =
Range =
t (
t (
68.4 f
-
43.0 f
-
ft
Shoreline Position Changes (
11,500
–
Accretion
Shoreline Change (ft)
Erosion
Recreational Berm (+5.0 ft NAVD88): Average =
Mean High Water (+1.4 ft NAVD88): Average =
Summary of Findings Mason Inlet Relocation Project
20
)
167,660 cy
-
)
ft
14.6 cy/ft (
-
*Survey Data Provided by the
Mason Inlet Relocation Project
14 ft NAVD88 =
-
ft
Volume Changes (cy/
otentially Some Northern Transport from
11,500
–
P
–
Volume Change Above
Volume Change (cy/ft)
Accretion
Erosion
roject
Significant Erosion Along Southern Portion of MIRP Due to Equilibration of 2020 MIRP PNorthern Portion of MIRP Stable Hurricane Isaias
Summary of Findings Mason Inlet Relocation Project
21
-
14 ft NAVD88
-
& cy)
ft
152,867 cy
167,660 cy
-
-
=
=
179,984 cy
213,330 cy
-
-
=
=
75,645 cy
-
=
13.3 cy/ft
14.6 cy/ft
-
-
Total Volume Loss Above
y/ft
15.7 cy/ft
18.6 cy/ft
-
Volume Changes (cy/
-
6.6 c
–
-
46.3 cy/ft
+82.0 cy/ft+99.8 cy/ft+84.9 cy/ft+82.8 cy/ft
+
––––
–
y/ft y/ft y/ft y/ft
t NAVD88 (Offshore Bar) = t NAVD88 (Closure) =
11.9 c13.7 c28.7 c34.6 c
----
ft NAVD88 (Wading Depth) =
ft NAVD88 (Offshore) =
4.0 14.0 f20.0 f30
----
Range = +5.3 cy/ft Range = Range = Range = Range =
167,660 cy Which is Equivalent to 40% of the Placement Volume from the
Above +1.4 ft NAVD88 (MHW) = Above Above Above Above Overall Volume Loss Along The MIRP:of -2020 MIRP Project. Accelerated Losses are Expected in the First Year PostConstruction. It
Should be Noted that the Northern Portion of the Project was Very Stable and Most Losses Occurred Adjacent to the Inlet.
Summary of Findings Mason Inlet Relocation Project
22
+67.4 ft)
+68.0 ft)
–
–
)
43.3 ft
-
41.9 ft
-
ft
(Range =
(Range =
t
t
6.1 f
-
6.3 f
-
ft
21,703
Shoreline Position Changes (
–
Accretion
Shoreline Change (ft)
Erosion
Recreational Berm (+5.0 ft NAVD88): Average = Mean High Water (+1.4 ft NAVD88): Average =
Summary of Findings Wrightsville Beach
23
)
229,143 cy
-
Typical Behavior
Typical Behavior
Not Typical
–
–
–10.6 cy/ft (
-
14 ft NAVD88 =
-
)
ft
ft
21,703
Volume Change Above
orth/Mason Inlet Experienced Volume Gains
Volume Changes (cy/
entral Experienced Significant Volume Losses
outh Experienced Significant Volume Losses
CSN
–
–––
Volume Change (cy/ft)
Accretion
Erosion
Wrightsville Beach Wrightsville Beach BehaviorWrightsville Beach
Summary of Findings Wrightsville Beach
24
yr)
yr
=
Average
14 ft
yr
-
8.5 cy/ft/
Background
-
Erosion Rate
184,679 cy/
16
(-
Subreach
229,143 cy
-
30,618 cy
-
=
=
373,966 cy
& cy)
753,450 cy
-
-
=
: Volume Losses Above
ft
=
47,241 cy
-
Due to Quiescent Weather After
:
=
1.4 cy/ft
10.6 cy/ft
-
-
y/ft
17.2 cy/ft
34.7 cy/ft
-
-
2.2 c
-
+13.2 cy/ft+17.4 cy/ft+17.3 cy/ft+14.5 cy/ft+3.4 cy/ft
–––––
Volume Changes (cy/
–
y/ft y/ft y/ft y/ft y/ft
229,143 cy Which is Slightly Higher than the Background
-
t NAVD88 (Offshore Bar) = t NAVD88 (Closure) =
11.1 c13.4 c26.5 c36.4 c63.4 c
-----
ft NAVD88 (Wading Depth) =
ft NAVD88 (Offshore) =
4.0 14.0 f20.0 f30
----
Range = Range = Range = Range = Range =
Above +1.4 ft NAVD88 (MHW) = Above Above Above Above Overall Volume Loss Along Wrightsville BeachNAVD88 Totaled Erosion Rate, Impacted Mostly by Higher Losses in the South Time Period
Between Surveys = 10 Months2021 Survey, It Is Likely That Majority of Annual Changes Have Been Captured In This Analysis
Summary of Findings Wrightsville Beach
25
Volume Change (cy/ft)
–
Elevation (ft NAVD88)
Borrow Source For The Wrightsville Beach CSDR Project
Summary of Findings Wrightsville Beach (Masonboro Inlet)
26
Volume Change (cy)
–
USACE Hydrographic Surveys
-
nlet
I
Masonboro
Summary of Findings Wrightsville Beach (Masonboro Inlet)
27
Volume Change (cy)
–
eodynamics Lase Scanner Surveys
G
-
Wrightsville Beach Spit
Summary of Findings Wrightsville Beach (Masonboro Inlet)
28
cy
Volume Change (cy)
–
= +193,439
Inlet)
2021 2021 = +587,999 cy
––
Masonboro
Change 2018
ach Laser Scanner Data Within the Permitted Borrow Area
each Laser Scanner Data and Missing Edges/Corners of Borrow Area
Volume Change 2020 Volume
Calculate Volume of the USACE Hydrographic Surveys & Wrightsville BeFilled in Data Gaps Between USACE Hydrographic Surveys & Wrightsville B
Summary of Findings Wrightsville Beach (
29
+46.0 ft)
+36.3 ft)
–
–
70.1 ft
26.3 ft
-
-
(Range =
(Range =
t
4.3 f
-
ft
39,293
Shoreline Position Changes (ft)
–
Shoreline Change (ft)
Accretion
Erosion
Recreational Berm (+5.0 ft NAVD88): Average = Mean High Water (+1.4 ft NAVD88): Average = +9.4 ft
Summary of Findings Masonboro Island
30
)
65,754 cy
-
1.7cy/ft (
Reaches
-
-
Reach
-
14 ft NAVD88 =
-
rth Sub
No
entral & South Sub
–
C
–
ft
39,293
Volume Change Above
Volume Changes (cy/ft)
–
Erosion
Accretion
Volume Change (cy/ft)
Moderate Erosion Along Masonboro Island Moderate Accretion Along Masonboro Island
Summary of Findings Masonboro Island
31
yr)
yr
=
Average
yr
14 ft
2.2 cy/ft/
-
87,254 cy/
Background
-
Erosion Rate
16
(-
+3,426 cy
65,754 cy
-
=
=
370,441 cy
18,983 cy
-
: Volume Losses Above
+
177,035 cy
-
=
=
Due to Quiescent Weather After
=
:
1.7 cy/ft
+0.1 cy/ft
-
4.5/ft
9.4cy/ft
-
-
+0.5 cy/ft
+17.0 cy/ft+18.4 cy/ft+21.5 cy/ft
+6.9 cy/ft+8.6 cy/ft
–––
––
Volume Changes (cy/ft & cy)
y/ft y/ft y/ft
65,754 cy Which is Slightly Lower than the Background
–
y/ft y/ft
-
t NAVD88 (Offshore Bar) = t NAVD88 (Closure) =
4.3 c7.3 c16.9 c22.2 c36.3 c
-----
ft NAVD88 (Wading Depth) =
ft NAVD88 (Offshore) =
4.0 14.0 f20.0 f30
----
Range = Range = Range = Range = Range =
Above +1.4 ft NAVD88 (MHW) = Above Above Above Above Overall Volume Loss Along Masonboro IslandNAVD88 Totaled Erosion RateTime Period Between Surveys = 9 Months2021 Survey & Low Background
Erosion Rates, It Is Likely That Majority of Annual Changes Have Been Captured In This Analysis
Summary of Findings Masonboro Island
32
Volume Change
–
; Therefore, Shoreline Change & Volume
Beachface
Ex: Transect 2)
nclude A Dune, Berm, & Aerial
Due To The Alignment Of The Transects Across Carolina Beach Inlet, Not All Profiles IChange Calculations Were Not PerformedShoaling & Use Of The Inshore Dredge Material Management Site
For CSDR Project(
Summary of Findings Freeman Park (Carolina Beach Inlet)
33
)
ft
Volume Change (cy/
–
Elevation (ft NAVD88)
Borrow Source For The Carolina Beach CSDR Project
Summary of Findings Freeman Park (Carolina Beach Inlet)
34
Volume Change (cy)
–
SACE Hydrographic Surveys
U
-
Carolina Beach Inlet
Summary of Findings Freeman Park (Carolina Beach Inlet)
35
cycy
Volume Change (cy)
–
+636,587
= +328,322 =
2021 2021
––
2019
Change
rea
ermitted Borrow Area
Volume Change 2020 Volume
Calculate Volume of the USACE Hydrographic Surveys Within the PFilled in Data Gaps Between Along Missing Edges/Corners of Borrow A
Summary of Findings Freeman Park (Carolina Beach Inlet)
36
21.1ft)
15.4 ft)
–-
–-
58.9 ft
-
27.5 ft
-
)
(Range =
(Range =
ft
t
t
38.2 f
-
23.3 f
-
ft
5,510
Shoreline Position Changes (
–
Accretion
Erosion Shoreline Change (ft)
Recreational Berm (+5.0 ft NAVD88): Average = Mean High Water (+1.4 ft NAVD88): Average =
Summary of Findings Freeman Park
37
77,709 cy)
-
14.1 cy/ft (
-
14 ft NAVD88 =
-
)
ft
ft
5,510
Volume Change Above
Volume Changes (cy/
–
Erosion Volume Change (cy/ft)
Accretion
Volume Losses Along Entire Reach Above All Elevations AnalyzedLargest Losses Near Carolina Beach Inlet
Summary of Findings Freeman Park
38
yr
yr)
=
Average
yr
66,900 cy/
Background 12.1 cy/ft/
Erosion Rate
-
15
(-
14 ft NAVD88
-
77,709 cy
-
31,652cy
-
=
=
137,219 cy
207,499 cy
-
-
=
=
25,892cy
-
& cy)
=
5.7cy/ft
14.1 cy/ft
-
Due to Quiescent Weather After 2021
-
ft
:
: Volume Losses Above
y/ft
24.9 cy/ft
37.7 cy/ft
-
-
4.7c
-
6.3 cy/ft19.2 cy/ft
+0.5 cy/ft
0.9 cy/ft
+2.2 cy/ft
––-–-
––-
y/ft y/ft y/ft
y/ft y/ft
Volume Changes (cy/
t NAVD88 (Offshore Bar) = t NAVD88 (Closure) =
7.4 c9.6 c41.8 c56.6 c63.7 c
–
-----
ft NAVD88 (Wading Depth) =
ft NAVD88 (Offshore) =
77,709 cy Which is Slightly Higher than the Background Erosion Rate
4.0 14.0 f20.0 f30
-
----
Range = Range = Range = Range = Range =
Above +1.4 ft NAVD88 (MHW) = Above Above Above Above Overall Volume Loss Along Freeman ParkTotaled Time Period Between Surveys = 8 MonthsSurvey, It Is Likely That Much of the Annual
Changes Have Been Captured In This Analysis but High Background Erosion Rates Indicate Potential for Additional Erosion Even with Quiescent Weather
Summary of Findings Freeman Park
39
+0.0 ft)
2.3 ft)
–
–-
47.8 ft
-
40.4 ft
-
)
ft
(Range =
(Range =
t
t
22.1 f
-
16.8 f
-
ft
18,089
Shoreline Position Changes (
–
Erosion
Accretion
Shoreline Change (ft)
Recreational Berm (+5.0 ft NAVD88): Average = Mean High Water (+1.4 ft NAVD88): Average =
Summary of Findings Carolina Beach
40
253,732 cy)
-
14.0 cy/ft (
-
14 ft NAVD88 =
-
)
ft
ft
18,089
Volume Change Above
rth & Central Experienced Significant Volume Losses As is Typical
outh Also Experienced Volume Losses (Typically Some Transects
Volume Changes (cy/
NoS
––
–
Subreaches
Accretion
Erosion
Volume Change (cy/ft)
Carolina Beach for These Carolina Beach Experience Accretion)
Summary of Findings Carolina Beach
41
yr)
yr
=
Average
yr
Background 16.4 cy/ft/
Erosion Rate
296,563 cy/
-
15
(-
14 ft NAVD88
-
253,732 cy
-
115,845 cy
-
=
=
305,481 cy
514,696 cy
-
-
=
=
81,535 cy
-
& cy)
=
6.4 cy/ft
ft
14.0 cy/ft
-
Due to Quiescent Weather After 2021
-
: Volume Losses Above
:
y/ft
16.9 cy/ft
28.5 cy/ft
-
-
4.5 c
-
0.2 cy/ft2.7 cy/ft
+1.4 cy/ft+1.9 cy/ft+0.1 cy/ft
––––-–-
y/ft y/ft y/ft y/ft y/ft
Volume Changes (cy/
–
t NAVD88 (Offshore Bar) = t NAVD88 (Closure) =
17.1 c23.1 c39.8 c47.1 c71.2 c
-----
ft NAVD88 (Wading Depth) =
ft NAVD88 (Offshore) =
253,732 cy Which is Slightly Lower than the Background Erosion Rate
4.0 14.0 f20.0 f30
-
----
Range = Range = Range = Range = Range =
Above +1.4 ft NAVD88 (MHW) = Above Above Above Above Overall Volume Loss Along Carolina BeachTotaled Time Period Between Surveys = 8 MonthsSurvey, It Is Likely That Much of the Annual
Changes Have Been Captured In This Analysis but High Background Erosion Rates Indicate Potential for Additional Erosion Even with Quiescent Weather
Summary of Findings Carolina Beach
42
+8.6 ft)
+13.0 ft)
–
–
51.1 ft
-
34.9 ft
-
(Range =
(Range =
t
t
)
ft
20.2 f
-
12.2 f
-
ft
15,342
Shoreline Position Changes (
–
Shoreline Change (ft)
ErosionAccretion
Recreational Berm (+5.0 ft NAVD88): Average = Mean High Water (+1.4 ft NAVD88): Average =
Summary of Findings Kure Beach
43
152,157 cy)
-
9.9 cy/ft (
-
14 ft NAVD88 =
-
)
ft
ft
15,342
Volume Change Above
rth & South Experienced Significant Volume Losses As is Typical for
entral Also Experienced Volume Losses (Typically Several Transects
NoC
Volume Changes (cy/
––
–
Volume Change (cy/ft)
Erosion
Accretion
Kure Beach These SubreachesKure Beach Experience Accretion)
Summary of Findings Kure Beach
44
yr)
yr
=
Average
yr
8.8 cy/ft/
Background
-
Erosion Rate
134,776 cy/
15
(-
14 ft NAVD88
-
74,447 cy
152,157 cy
-
-
=
=
210,412 cy
401,001 cy
-
-
=
=
69,537 cy
-
=
4.9 cy/ft
9.9 cy/ft
-
Due to Quiescent Weather After 2021
-
& cy)
:
y/ft
ft
: Volume Losses Above
13.7 cy/ft
26.1 cy/ft
-
-
4.5 c
-
8.5 cy/ft
+0.9 cy/ft+3.7 cy/ft+8.0 cy/ft+5.7 cy/ft
–––––-
y/ft y/ft y/ft y/ft y/ft
t NAVD88 (Offshore Bar) = t NAVD88 (Closure) =
13.9 c18.3 c29.0 c38.3 c53.7 c
-----
Volume Changes (cy/
ft NAVD88 (Wading Depth) =
ft NAVD88 (Offshore) =
–
152,157 cy Which is Slightly Higher than the Background Erosion Rate
4.0 14.0 f20.0 f30
-
----
Range = Range = Range = Range = Range =
Above +1.4 ft NAVD88 (MHW) = Above Above Above Above Overall Volume Loss Along Kure BeachTotaled Time Period Between Surveys = 8 MonthsSurvey, It Is Likely That Much of the Annual Changes
Have Been Captured In This Analysis but High Background Erosion Rates Indicate Potential for Additional Erosion Even with Quiescent Weather
Summary of Findings Kure Beach
45
+29.1 ft)
+47.2 ft)
–
–
39.4 ft
20.1 ft
-
-
(Range =
(Range =
t
)
ft
3.4 f
-
ft
16,799
Shoreline Position Changes (
–
Shoreline Change (ft)
Accretion
Erosion
Recreational Berm (+5.0 ft NAVD88): Average = Mean High Water (+1.4 ft NAVD88): Average = +7.3 ft
Summary of Findings Fort Fisher
46
33,391 cy)
-
2.0 cy/ft (
-
14 ft NAVD88 =
-
)
ft
ft
16,799
Volume Change Above
isher Central Experienced Volume Gains
F
-
Volume Changes (cy/
–
Accretion
Volume Change (cy/ft)
Erosion
Mostly Volume Losses Along the Entire ReachSmall Portion of Fort
Summary of Findings Fort Fisher
47
yr)
yr
=
Average
yr
Background
Erosion Rate+2.4 cy/ft/
15
(+40,176 cy/
14 ft NAVD88
-
+34,761 cy
33,391 cy
-
=
=
509,346 cy
141,736 cy
-
-
=
3,408 cy
=
-
=
2.0 cy/ft
+2.1 cy/ft
Due to Quiescent Weather After 2021
-
:
& cy)
y/ft
ft
: Volume Losses Above
8.4 cy/ft
30.3 cy/ft
-
-
0.2 c
-
+17.2 cy/ft+22.7 cy/ft+20.6 cy/ft+21.0 cy/ft
+7.4 cy/ft
––––
–
y/ft y/ft y/ft y/ft
y/ft
t NAVD88 (Offshore Bar) = t NAVD88 (Closure) =
8.0 c13.8 c24.5 c31.0 c73.5 c
-----
ft NAVD88 (Wading Depth) =
ft NAVD88 (Offshore) =
Volume Changes (cy/
–
33,391 cy Which is Atypical Given Background Erosion Rates are
4.0 14.0 f20.0 f30
-
----
Range = Range = Range = Range = Range =
Above +1.4 ft NAVD88 (MHW) = Above Above Above Above Overall Volume Loss Along Fort FisherTotaled AccretionalTime Period Between Surveys = 8 MonthsSurvey & Historically Accretional Trends,
It Is Likely That Much of the Annual Changes Have Been Captured In This Analysis
Summary of Findings Fort Fisher
48
17.5 ft
8.9 ft
-
-
)
ft
Recreational Berm (+5.0 ft NAVD88) = Mean High Water (+1.4 ft NAVD88) =
Shoreline Position Changes (
–
Accretion
Shoreline Change (ft)
Erosion
Summary of Findings Pleasure Island
49
516,990 cy)
-
9.3 cy/ft (
-
)
ft
14 ft NAVD88 =
-
Volume Change Above
Volume Changes (cy/
–
Volume Change (cy/ft)
ErosionAccretion
Summary of Findings Pleasure Island
50
MIRP F8 South
MIRP F8 Mason Inlet
North/Mason Inlet
Wrightsville Beach North
Wrightsville Beach Central
)
Wrightsville Beach South
ft
Masonboro Island North
Masonboro Island Central
Masonboro Island South
Freeman Park
Carolina Beach North
Carolina Beach Central
Carolina Beach South
Kure Beach North
Unit Volume Change (cy/
Kure Beach Central
–
Kure Beach South
Fort Fisher North
Fort Fisher Central
Fort Fisher South
Accretion
Erosion
Average Volume Change (cy/ft)
Summary of Findings New Hanover County
51
MIRP F8 South
MIRP F8 Mason Inlet
North/Mason Inlet
Wrightsville Beach
Wrightsville Beach Central
Wrightsville Beach South
Masonboro Island North
Masonboro Island Central
Masonboro Island South
Freeman Park
Carolina Beach North
Carolina Beach Central
Carolina Beach South
Kure Beach North
Kure Beach Central
Cumulative Volume Change (cy)
–
Kure Beach South
Fort Fisher North
Fort Fisher Central
Fort Fisher South
Accretion
Erosion
Cumulative Volume Change (cy)
Summary of Findings New Hanover County
52
–
Could
–
–
South
-
Slightly Less Than Background Erosion RateSlightly Higher Than Background Erosion Rate
-
Uncharacteristic Based on Historical Accretion Trends
Annual Volume Change (cy/ft)
–
: Overall Moderate Volume Losses (Slightly Higher Than Background Erosion Rate)
: Minor Volume Losses
: Overall Substantial Volume Losses (Slightly Lower than Background Erosion Rate
: Significant Volume Losses -
: Overall Significant Volume Losses (Slightly Higher Than Background Erosion Rate
: Minor Volume Losses –
South Subreach
Subreach
–
MIRP Confined to Southern Portion of Project and Stable Northern Portion of Project Wrightsville Beach With Much Higher Than Typical Losses in Wrightsville Beach Masonboro IslandFreeman
ParkCarolina Beach Could be Impacted by 8 Month Timeframe), Including Losses in Historically More Stable Carolina Beach Kure Beach be Impacted by 8 Month Timeframe), Including Losses
in Historically More Stable Kure Beach Central Fort Fisher
Summary of Findings Overall Summary
53
Target is 0
-2021
Essential For
Volume Losses =
CSDR Projects Are
Volume Placement
Maintaining Beaches
for NHC
–2021
yr
y/ft/
6.3 c
t NAVD88 From 2005/2006
-
14.0 f
-
Calculate Volume Change Above Subtract Out Placement Volumes From 2005/2006 Annualized Background Erosion Rate =
Summary of Findings Background Erosion Rate
54
yr,
NOT
ome
S
t NAVD88
i.e.2-
14 f
-
unds were to ever
M&N Performed
-
Federal F
tart the Process of Planning for and
S
Level of Protection
yr) Using SBEACH
-
pproach to
Design
A
yr, & 100
ourishments Projects if
-
N
Level of Protection
hore Transport for Various Return Period Storms (
S
-
yr, 50
-
esign
uture
yr, 25
-
each?
What is the Largest Return Period Storm the Beach can Withstand?What Level Storm do we want to Ensure Protection Against for the Entire BVolume of Sand Required from the First Row of
Structures out to to Protect Against the
yr, 10
New Topic to be Included in the Monitoring Report Modeling as a Proactive Optimizing Fcome to Fruition.The Concept Of Nourishment Triggers Aims to Provide Equal Protection to all Parts
of the BeachModeled Cross5-Determined the Existing “Level of Protection” for the BeachDetermine DDeveloped Nourishment Triggers Based on Desired Level of Protection
Summary of Findings Nourishment Triggers
55
10 YR Level of Protection
esign
xisting Level of Protection
E
––D
Wrightsville Beach Wrightsville Beach
Summary of Findings Nourishment Triggers
56
2021
2020
2019
2018
2017
2016
2015
2014
olume Status
V
–
14 ft NAVD88 (cy/ft)-Volume Above
Wrightsville Beach
Summary of Findings Nourishment Triggers
57
25 YR Level of Protection
esign
xisting Level of Protection
E
––D
Carolina Beach Carolina Beach
Summary of Findings Nourishment Triggers
58
2021
2020
2019
2018
2017
2016
2015
2014
olume Status
V
–
14 ft NAVD88 (cy/ft)-Volume Above
Carolina Beach
Summary of Findings Nourishment Triggers
59
25 YR Level of Protection
esign
xisting Level of Protection
E
––D
Kure Beach Kure Beach
Summary of Findings Nourishment Triggers
60
2021
2020
2019
2018
2017
2016
2015
2014
olume Status
V
–
14 ft NAVD88 (cy/ft)-Volume Above
Kure Beach
Summary of Findings Nourishment Triggers
61
Final Thoughts
–
erm Trends
T
-
Project PerformanceNatural Erosion/Accretion PatternsRefinement Of Hotspot & Nodal Point LocationsProvides Data For Model Calibration (Shorelines, Bathymetry, etc.)Provides Current Conditions
From Which To Assess Alternatives
olumes And Cycles
Assessment Of Specific Sand Placement Locations And VolumesAssessment of Beach Conditions With Respect to Nourishment TriggersEstablishment Of Long
Assessment Of Background Erosion Rates With Respect To Maintenance VDetermination Of Longshore Extent Of Inlet InfluencesAssessment Of Borrow Area Volumes Throughout Nourishment CycleAnnual
Monitoring Works In Conjunction With Coastal Modeling
Summary of Findings Future Datasets Will Improve Analyses
62
2021)
-
2021)
-
2021)
-
ay 2021
M
2021)
-
–
Survey TransectsSurvey EquipmentShoreline ChangeVolume ChangeStorm ActivityMaintenance ActivityShoreline & Volume Change (2020 Inlet Conditions (2020 Background Erosion Rates (2005/2006
Nourishment Triggers (2014
Data CollectionProject MethodologyKey Events: March 2020 Summary of FindingsQ&A/Discussion
Presentation Outline
63
Q&A / Discussion