Engineering Guidelines Training

NJ Living Shorelines Guidelines

Jon K. Miller

Andrew Rella

Amy Williams

May 29, 2015

Objectives

• Provide guidance to engineers and contractors on the engineering components of living shorelines

design

• Provide a common starting place to ensure consistency with GP 29 (N.J.A.C. 7:7-7.29) – “Living

Shorelines GP”

• Reduce the number of failures due to poor engineering/construction

Approach

1. Identify factors relevant to living shoreline

design

• Mix of traditional, traditional evaluated non-

traditionally, and non-traditional

2. Describe approaches for determining those

parameters

3. Provide example applications of those

parameters to design

• Sills*, breakwaters*, joint planted revetment,

reef balls*, living reef*

* It is assumed a marsh is planted behind the structures

Suggested Design Approach

ALTERNATIVE SELECTION

Parameters

Quantitative Interpretation

of Selection Criteria

SYSTEM PARAMETERS

Erosion History

Sea Level

Tidal Rage

Erosion History

• Define the problem

• Desktop Analysis

• Compare historical maps

Sea Level Rise

• Landscape features may drown

in place

• Desktop Analysis

• Alternatives analysis

• USACE and NOAA Guidance

Tide Range

• Determines amount of

overtopping/transmission

• Vegetation is extremely sensitive to

its position with respect to the tide

• Invertebrate growth is sensitive to

position within the water column

HYDRODYNAMIC PARAMETERS

Wind Waves

Wakes

Currents

Ice

Storm Surge

Wind Waves

• Along with wakes, typically the dominant cause of erosion

• Both the maximum and the average wave may be of concern

• Basis for most of the critical structural design parameters

• Fetch Analysis

• SMB Analysis

Wakes

• May represent a force as big or larger than

wind waves

• Can be difficult to discern from wind waves

• Measured vs Modeled

• Desktop Analysis

• Collect observational data

Currents

• Can uproot vegetation

• Transports ice and debris

• Scour

• Desktop Analysis

• NOAA, USGS, USACE, local climatologists

Ice

• Known to be important, but data lacking

• Desktop Analysis

• Ice climatology (US Coast Guard obs)

• Satellite Imagery (no info on thickness)

Storm Surge

• Surge can be less important because water overtops the structure

• Desktop Analysis

• FEMA flood maps

• NOAA tides and currents extreme water level analyses

TERRESTRIAL PARAMETERS

Upland Slope

Shoreline Slope

Width

Nearshore Slope

Offshore Depth

Soil Bearing

Upland Slope

• Measured from approximately spring high water to point at which upland levels off

• Critical for vegetation

• Milder slopes have less scarping

• Desktop Analysis

• DEM’s, LIDAR

Shoreline Slope

• Shoreline or intertidal slope important for marsh/beach development

• Defined from MLLW to Spring High Water Line

• Desktop Analysis

• DEM’s, LIDAR, new USGS seamless topo/bathy

• New USGS seamless topo/bathy

Nearshore Slope

• Influences nearshore waves and currents

• Influence depth at structure

• Stable platform required for structure

• Desktop Analysis

• NOAA, Bathymetric charts/DEM’s

Offshore Depth

• Influences nearshore waves

• Influences size of structure and amount of fill

• Desktop Analysis

• NOAA, Bathymetric charts/DEM’s

• Bathymetric Survey

Soil Bearing Capacity

• Must be sufficient to resist settling

• Desktop Analysis

• Existing maps: topographic, geologic,

groundwater, dredging records, etc

• Site visit (1)

• Walking the site

ECOLOGICAL PARAMETERS

Water Quality

Soil Type

Sunlight Exposure

Water Quality

• Impacts growing conditions for both flora and fauna

• Primary parameters

• Dissolved Oxygen – produced by photosynthesis, consumed during respiration

• Varies seasonally, daily tidally, with depth

• NJ State Surface Water Quality Criteria

• Desktop Analysis

• USGS, EPA, NJDEP, Universities, NGO’s

• Consult a biologist/ecologist

Soil Type

• Soil conditions impact growth rate and root penetration

• Desktop Analysis (1)

• GIS Maps, Existing soil records, Dredge spoil (dumping) records

Sunlight Exposure

• Sunlight is required for photosynthesis which impact water quality

• Terrestrial vegetation also requires sunlight

• Desktop Analysis

• Google earth, bing

Additional Considerations

• End Effects

• Width/Space

• Constructability

• Native/invasive

• Debris Impact

• Monitoring

Additional Considerations

• End Effects

• Width/Space

• Constructability

• Native/invasive

• Debris Impact

• Monitoring

• A marsh requires a minimum amount of space

• Beaches/marshes provide additional energy dissipation

• Most states prohibit fill below MHW

• NJ allows fill to the 1977 tidelands map for restoration activities

Additional Considerations

• End Effects

• Width/Space

• Constructability

• Native/invasive

• Debris Impact

• Monitoring

Additional Considerations

• End Effects

• Width/Space

• Constructability

• Native/invasive

• Debris Impact

• Monitoring

Phragmites australis

Additional Considerations

• End Effects

• Width/Space

• Constructability

• Native/invasive

• Debris Impact

• Monitoring

Additional Considerations

• End Effects

• Width/Space

• Constructability

• Native/invasive

• Debris Impact

• Monitoring

“Build and Maintain”

Websites for Analysis

33

• Google Earth

• www.historicaerials.com

• US Army Corps guidance/procedure

• http://www.corpsclimate.us/docs/EC_1165-2-212%20-

Final_10_Nov_2011.pdf

• NOAA guidance

• http://www.habitat.noaa.gov/pdf/slr_workshop_report_nove

mber_2011.pdf

• NOAA (http://tidesandcurrents.noaa.gov/curr_pred.html)

• USGS (http://waterdata.usgs.gov/nj/nwis/rt)

• US Army Corps of Engineers (http://cirp.usace.army.mil/)

• Local climatologies (https://www.hrnerr.org/hudson-river-

sustainable-shorelines/shorelines-engineering/physical-forces-

statistics/)

• DEM’s (http://www.state.nj.us/dep/gis/)

• Lidar (http://www.csc.noaa.gov/)

• NOAA (http://estuarinebathymetry.noaa.gov/midatlantic.html)

• USGS (http://nj.usgs.gov/infodata/waterquality.html)

• EPA

(http://iaspub.epa.gov/tmdl/attains_state.control?p_state=NJ&p_

cycle=2006)

• NJDEP (http://www.state.nj.us/dep/wms/wqde/)

• Universities (http://www.monmouth.edu/university/coastal-water-

quality-real-time-monitoring-program-ver-2.aspx)

• NGO’s (http://nynjbaykeeper.org/resources-programs/advocacy-

legal-campaigns/how-is-the-water/)