the Paul S. Sarbanes Ecosystem Restoration Project at Poplar Island

Wetland Development in Dredged
Material at the Paul S. Sarbanes
Ecosystem Restoration Project at
Poplar Island
Doldon Moore
Maryland Board of Public Works
Wetlands Administration
27 th International Submerged Lands Management Conference
Traverse City, MI October 26-29, 2008
Maryland Port Administration
USACE Baltimore District
Maryland Environmental Service

Overview
• Background
• Wetland Development
• Lessons Learned
• Monitoring

Paul S. Sarbanes Ecosystem Restoration
Project at Poplar Island
• Dredged material placed from Baltimore Harbor Approach
Channels
• Island restoration will re-establish the approximate 1847 footprint

Project Location
Mid-
Chesapeake Bay,
Maryland
Talbot County

Tilghman Island
Poplar Island
2000
Coaches Island
Jefferson Island
South Central
Poplar Island
Middle
Poplar Island
Sunken Barges
North Point
South

Landmass Comparison 1847-1993

Poplar Island Specifications
• Size: 1,140 acres
• Perimeter dike: 40,000 ft
• Capacity: 42 mcy
• Cost: $407 million
• Uplands: 570 acres (50%)
• Wetlands: 570 acres (50%)
• To date, approximately 13 mcy
dredged material placed
• Projected placement life until 2015

Poplar Island Site Development
EAST
Cell 6
west
• 6 Large Containment Cells: 4 Wetland Cells & 2 Upland Cells
• Wetland Cells Temporarily Divided via Interior Dikes
• Wetland Cells- 80% Low Marsh & 20% High Marsh

• Wetland Cell “3D”
• 32 acres
Wetland Cell Development

Wetland Cell Development
Wetland Cell Development is a
Four Phase Process:
• Inflow and Crust Management
• Grading and Channel Development
• Inlet Structure Construction
• Planting

Wetland Cell Development
Inflow and Crust Management: April ‘01-Nov. ‘03
•0.35 million cubic yards
(mcy) of dredged material
inflowed into Cell 3D
•Crust develops from
dewatering methods
•Goal was to maximize
consolidation and achieve the
appropriate elevations

Crust Management
Desiccation Cracks
Pontoon trencher
Pontoon Excavator

Wetland Cell Development
Grading & Channel Development: Dec. ‘03-Oct. ‘04
Channel Excavation
•Material excavated from channels was redistributed by grading
•High Marsh elevations: Approximately +2.2 ft
•Low marsh: Approximately +1.5 ft

Wetland Cell Development
Inlet Structure Construction: Dec. ’04 – Jan. ‘05
Pipes allow
tidal interaction
Weir boards

Spillways
Interior of spillway,
pipes lead to the
Bay
Spillway
boarded up with
weir boards

Wetland Cell Development
Inlet Structure – Opening to Tidal Flow: March ‘05
Removing Weir boards
Cell 3D during 1 st opening
•Opened to tidal flow in March to note any areas of erosion before planting
•Eventually structure will be removed in addition to the road above so that
tidal inlet resembles a natural channel

Wetland Cell Development
Planting: Planning
Cell 3D Features:
DESIGN
TREATMENTS
FEATURE
Wetland Species Spartina patens,
Spartina alterniflora
Density of Geese 100’ x 100’, 75’ x 75’,
Fencing
50’ x 50’ and 25’ x
25’
Wetland Plant 1’, 2’, 3’, 4’, 6’
Density
Addition of None, 0.5 oz., 1.0 oz.
Fertilizer
Method of Planting Volunteer,
Contractor
Type of Planting Seed, Container,
Plug and Bare Root
Type of Substrate Dredged,
Sandy/Dredged,
Sandy
USACE, 2004

Wetland Cell Development
Marsh Planting: April - July 05’
•Total area planted: 897,500 sq ft
•Total Spartina alterniflora plugs: 312,560
•Total Spartina patens plugs: 174,160
•Planting conducted by a contractor and volunteers
organized by the National Aquarium in Baltimore
(6 acres).

Cell 3D October 2002 Cell 3D July 2006

Cell 3D Time Sequence
(view looking east)
June 2005 August 2005
June 2006

Monitoring Elements
• Vegetation surveys
• Plant chemical composition
• Photo-documentation
• Visual inspections
• Soil composition

Lessons Learned
Method of Planting
200
Poplar Island Cell 3D Stem Height
October 2006
•Areas planted by the volunteers
had similar biomass in
comparison to contractor
plantings
Height (cm)
150
100
50
0
High Marsh
Low Marsh
Contractual
Volunteer
•Volunteers are suitable to use for
marsh plantings at Poplar in
terms of success
Percent
120
90
60
30
Poplar Island Cell 3D Percent Cover
Poplar Island Cell 3D Percent Cov
October 2006
October 2006
0
High Marsh
Low Marsh
Contractual
Volunteer
UMCES, 2007

Lessons Learned
Fertilizer Additions
• Quadrants with no
fertilizer amendments
had the same, if not more
biomass than the
quadrants with fertilizer
Height (cm)
180
150
120
90
60
30
0
Poplar Island Cell 3D Stem Height
July 2006
High Marsh
Low Marsh
a
• Dredged material
contains high amounts of
ammonium and
phosphorus
120
90
No Fert.
Fert.
Poplar Island Cell 3D Percent Cover
July 2006
b
• Fertilizer should not be
used in future plantings
Percent
60
30
0
High Marsh
Low Marsh
No Fert.
Fert.
UMCES, 2007

Lessons Learned
Type of Planting, Goose Fencing Density, Planting Density
•Plugs appear to be the most reliable means of marsh establishment
•Proper seed prep (pre-wet, chilled seeds) may help yield better
results in dredged material
•Seeds have a much lower cost, so we will continue to experiment
with using them
•Plant spacing can be increased to 3 feet spacing except on channel
edges where more erosion is likely to occur
•Geese were able to fly into the 100’ X 100’ grid and predate on
plants; the 75’ X 75’ grid for fencing will be utilized in the future

Lessons Learned
Mineral Nutrition – Too much of a good thing
• Sediments were characterized as having an abundance of
available nitrogen (as ammonium).
• In 2007 some portions of the low marsh had much less growth
in comparison to 2006.
• It is speculated that the high nitrogen content in the dredged
material caused the plants to have much more above than
belowground biomass; this causes lodging which can inhibit
plant growth during the next growing season.
• As nitrogen accumulates in plant tissue it becomes more
attractive to bugs and fungus and may make the plants more
susceptible to infection.

Lessons Learned
Mineral Nutrition – Too much of a good thing
• The vegetation will
gradually remove
nitrogen from the
sediments and over
time Cell 3D should
have a more typical
growth pattern.
•Ongoing studies will
continue track
progress of Cell 3D.
Including tissue
sampling and above
and belowground
biomass surveys.
July 2007

• Fertilization is not needed
Lessons Learned
Summary
•Volunteers plant just as well as contractors (with the
proper oversight)
• Plant spacing can be increased to 3 foot spacing except on
channel edges
•Though plugs are more efficient at marsh establishment
seeds can still be used in moderation to cut costs as long as
they are prepped properly
•75 X 75 foot grid for goose fencing works fine
•Nitrogen levels in plant tissue needs to be monitored
closely as well as above to belowground biomass ratios.

“POP”ular Destination
Sandpiper
Great Blue Heron
American Avocet
Willet
Tree Swallow
Gulls
Red-winged Blackbird
Snowy Egret
Black Skimmer

Working Group
• Meet with Working Group semi-annually in May and
November
• HSG meets every February and in August, if needed
• MSG meets in August
• Electronically transmit monthly newsletters to the WG
members
• Communicate with Working Group and sub-groups
electronically when need advice, proposal review, or to
address specific site conditions
• Group members are very responsive & play an active role
in site development

Framework Monitoring
• Exterior sediment
quality
• Exterior water quality
• Benthics – community
and tissue
• Discharge monitoring
• Construction turbidity
monitoring
• Shellfish bed
sedimentation
• Interior water quality-
algae monitoring
• Wetland vegetation
• Wetlands use by fish
• Fisheries use of
exterior proximal
water
• Wetlands use by
wildlife
• Bird utilization counts
• Submerged aquatic
vegetation
• Diamondback terrapin
monitoring
• Wetland cell soil and
vegetation

Framework Monitoring
• Principal Investigators prepare annual reports detailing the
results of Framework Monitoring elements
• These are summarized and included in a comprehensive
Annual Report
• Recommendations regarding changes to the monitoring
elements are reviewed with the HSG every February
• These recommendations are then used to update the
Adaptive Management Plan
• The recommendations are also added to the Habitat
Development Framework, which is updated annually and
details how to develop the desired habitat

Example of Working Group
Coordination
• One of the EIS goals is to maintain sparsely vegetated
habitat islands for colonial water birds, such as terns
• These islands were originally constructed of oyster shell on
top of sand
• These shell covered islands are not staying sparsely
vegetated
• A significant amount of time and effort was going into
cutting down the vegetation and applying pre-emergent
emergent
herbicide before the terns arrive each year
• However, the vegetation was growing back during the
nesting season and HSG was concerned that this re-growth
could cause nesting failure

Shell Covered Nesting Islands
Shell island
approximately 1 year
after construction
Shell island in 2003,
after weed-whacking

Reconstructing Nesting Islands
• The maintenance issue was discussed with the HSG to
determine what needed to be done to make the islands
sparsely vegetated and as maintenance free as possible
• Looked at various substrates and treatments to apply on
top of the existing substrate
• Determined that whole oyster or clam shell were not
available, so group suggested pea gravel as the cover
• A plan was developed where geo-textile, rock salt and pea
gravel are being tested in various combinations on 2 of the
original shell covered islands
• A monitoring plan was also developed to determine the
success of these various treatments

Island Re-construction

Terns!!
Final Result

Questions