Myrtle Beach Hurricane and Storm Protection Project

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Myrtle Beach Hurricane and Storm Protection
Project

• 2007-2009

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Myrtle Beach Project Getting Started

• Feasibility Study
• Had to be economically justified BCR of 3.7
• EIS completed for 50 year life of project
• -Authorization 1990
• -First nourishment 1996-1998 (65 Federal/35
  Non-Federal)
• -Must be a public beach Public access required
  at least every ½ mile

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Myrtle Beach Project Environmental

• Environmental Effects/Issues
• National Environmental Policy Act
  (Environmental Assessment / Environmental Impact
  Statement)
• Coastal Barrier Resources Act (CBRA)
  restrictions on borrow sites
• Evaluation of general biological effects
• Sea turtle nesting effects
• Benthic organism effects borrow site surf
  zone
• Burrowing macro-invertebrate effects
• Shore bird effects (nesting, foraging, loafing)

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Myrtle Beach Project Environmental

• Environmental features
• Turtle nesting season May 1st thru November
  30th
• Peak nesting activity after June 1st
• Till entire length of new beach
• Flatten escarpments as they form
• Nighttime monitors to protect nesting sea turtles
  (100 ft buffer)
• relocate nests

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Myrtle Beach Project

• Borrow site investigation
• side scan sonar and sub-bottom profiling
• vibracores
• Cultural Resource Survey side scan sonar
  magnetometer

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Myrtle Beach Project Beach Nourishment Basics

• Technical
• Protective dune fronted by a sacrificial berm
• Dune height based on maximizing the level of
  protection (usually a 25 or 50 year storm event)
• Width of sacrificial berm determined by erosion
  rate and renourishment cycle
• Typically 75 yd3 to 100 yd3 per linear foot
• Renourishment cycle based on computer models
  (life cycle analysis using historical erosion
  rates and storm frequencies)
• Borrow source must be compatible with native
  beach

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Myrtle Beach Project
The original beach nourishment project from 1996
to 1998 placed 6.4 million cubic yards of sand at
a cost of 51.3 million. Most recent
renourishment 2007-2009 placed slightly more than
3 million cubic yards Additional renourishment
authorized as needed for 50 years, if funds
appropriated Estimated need for renourishment is
every 8-10 years (unless emergency renourishment
needed)
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Myrtle Beach ProjectPublic Law 84-99 (Emergency
Flood Control Act of 1955)

• Repairing Federally Authorized Hurricane and
  Storm Protection Projects is one of eight major
  items authorized by P.L. 84-99.
• If a major storm and Congress approves emergency
  funding, repairs 100 Federally funded

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Myrtle Beach Project

• Typical periodic renourishment construction cost
  shared 65/35
• Emergency P.L. 84-99 renourishment funded 100
  Federal
• Myrtle Beach most recent renourishment a
  combination of both types of funds

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Myrtle Beach Project Scope and Sponsors
N. Myrtle Beach
Horry County
Reach 1 ¾ M cubic yds
Myrtle Beach
Reach 2 1.5 M cubic yds
Henry E. Brown Jr. (R) 1st Congressional
District, SC
Reach 3 ¾ M cubic yds

• 29M Project,
• Hurricane Ophelia FCCE funds (14.7M)
• Remainder cost shared 65 Federal / 35 State
  Local Sponsors
• 25 miles of Coastline 3 million cubic yards of
  sand
• Enough sand to fill the Empire State Building
• 13 Month Construction Schedule

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Myrtle Beach Project Great Lakes Dredge and Dock
(GLDD) Plan
Reach 1 Last (Jul-Oct)
Reach 2 Second (Mar-Jul)
Reach 3 First (Nov-Feb)

• Work from South to North
• Nov 07 GLDD mobilize 1st dredge
• Dec 07 GLDD mobilize 2nd dredge

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Myrtle Beach Project Before and After Reach 3
(Surfside Beach) February 2008
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Myrtle Beach Project Change to Scope? Are there
Off Shore UXOs in our Borrow Sites?

• On 8 Nov 1943, the Myrtle Beach Airstrip was
  renamed Myrtle Beach Army Air Field (MBAAF).
• It consisted of two bombing ranges and three
  gunnery ranges.
• There was a secondary airstrip at Surfside Beach,
  about 10 miles south of MBAAF known as Wampee
  Flight Strip.

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Myrtle Beach Project Change to Scope? Off Shore
UXOs

• Possible Courses of Action
• COA 1 Do nothing and hope no UXOs are found
• COA 2 Ask contractor to screen for UXOs off
  shore
• (most expensive and will slow down rate of sand
  to beach)
• COA 3 Ask contractor to screen for UXOs at
  beach
• (will slow work down but not as much as COA 2)
• Corps asks Contractor for a cost/scope proposal
  for new requirement
• Jan 08 Proposal received from GLDD for 1M-2M
• Feb 08 Corps decides cost does not outweigh the
  risk/benefit

15
Myrtle Beach Project Change to Timeline? New
Orleans District must respond to Midwest Floods

• New Orleans District Newsletter (10 April 2008)
• The Corps is currently running five dredges 24
  hours a day, seven days a week in the Southwest
  Pass near the mouth of the river to maintain
  river navigation.
• During high river conditions, shoaling is rapidly
  occurring near the mouth of the Mississippi River
  where surveys are taken daily and dredge
  assignments are constantly being issued to keep
  pace with the dynamic changes in the river.

16
MYRTLE Beach Project Change to Timeline?25
March 2008

• 0900hrs GLDD tells Charleston District they
  want to bid on Mississippi Emergency dredging.
• Bids due in two hours!
• GLDD says they will cut off the contract if
  we allow them 4-6 week extension on the project
  completion date.
• GLDD will return to Myrtle Beach in early July
• 0930 Corps meeting to discuss courses of action
  -
• COA 1 Accept GLDD offer knowing that
• if GLDD is awarded the New Orleans contract, the
  dredge will be off the Myrtle Beach project over
  4 months
• Reaches 1 and 2 will be undernourished during
  Hurricane Season
• COA 2 Tell GLDD we will hold them to our
  contract
• 1000 Charleston asks GLDD to request a 1 hour
  delay
• 1000 PM calls Horry County, Myrtle Beach and N
  Myrtle Beach to explain situation and to get
  their input.
• 1100 Corps approves GLDDs proposal to bid on
  New Orleans work

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Myrtle Beach Project - GLDDs New Plan
Reach 1 Second (Jul Aug 08)
Reach 2 Last (Sep - Nov 08)
Reach 1 Last (Jul-Oct 08)
Reach 2 Second (Mar-Jul 08)

Reach 3 First (Nov 07- Feb 08)

• The Change to Schedule results in
• Bad Press from N Myrtle Beach (height of tourist
  season)
• Myrtle Beach is happy beach remains untouched
  over summer
• Lesson in public information about impacts during
  construction

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Myrtle Beach Project What Happens?

• Chocolate Milkshake
• Shaped by bulldozers
• Where did all the sand go? settling period
• Sacrificial sand and protective berm

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Myrtle Beach Project Profile
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Myrtle Beach Project
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Myrtle Beach Project
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Myrtle Beach ProjectCutterhead Pipeline not
suitable for borrow area
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Myrtle Beach Project
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Myrtle Beach Project Hopper Dredge
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Myrtle Beach Project
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Myrtle Beach Projectexample of contrast-
Virginia Beach
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Myrtle Beach Project Survey Marks
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Myrtle Beach Project
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Myrtle Beach Project
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Myrtle Beach Project
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Myrtle Beach Project
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Myrtle Beach Project - note shielded nightlight
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Myrtle Beach Project
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Myrtle Beach Project Fencing Grassing

• Fences trap sand and build dunes.
• Native dune grasses planted immediately behind
  fences.
• Eventually grasses grow over dune and help
  stabilize it

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Myrtle Beach Project
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Myrtle Beach Project Fencing and Grassing
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Myrtle Beach Project
QUESTIONS?