adventure gut presentation may 2010 comp

ADVENTURE GUT RESTORATION DEMONSTRATION PROJECT

• Michael Shaffer, EIExtension Associate, Biological & Agricultural EngineeringNorth Carolina State University

• Julie Wright,RC&D Coordinator, USDA NRCS, USVI RC&D Council, Inc.

• Greg Jennings, PhD, PEProfessor, Biological & Agricultural EngineeringNorth Carolina State University

First, lets cover some stream and watershed basics

•Precipitation

•Infiltration

•Runoff

Stream Corridor Restoration: Principles, Processes, and Practices. 1998. Federal Interagency Stream Restoration Working Group.

Sediment Transport

Flowing water performs

work through:

• Overcoming Friction

• Erosion

• Movement & Deposition

(of stream materials)

http://www.uwsp.edu/gEo/faculty/ritter/geog101/textbook/fluvial_systems/geologic_work_of_streams.html

Bankfull Stage“corresponds to the discharge at which channel maintenance is the most effective, that is, the discharge at which moving sediment, forming or removing bars, forming or changing bends and meanders, and generally doing work results in the average morphologic characteristics” (Dunne and Leopold,1978)

Stream Corridor Restoration: Principles, Processes, and Practices. 1998. Federal Interagency Stream Restoration Working Group.

What are stable streams?Accessibility to a floodplain connection for any flows greater than bankfull allows the dissipation of stream energy, reducing erosive forces

What are unstable streams?Lack of a floodplain connection for the majority of stream flow,

concentrates the force of the water, putting all of the stream energy into the stream bed and banks.

Using a flood plain:Low flow and Flood

flow

Little Garvin Creek, Clemson, SC

• Dimension (bankfull & flood flow)• Pattern (meander)• Profile (bed profile)• Floodplain connection

Channel Morphology & Floodplain Connection

2005 NCSU Rocky Branch 2006

What did Adventure Gut look like?• Extremely incised

• Exposed raw earth banks• Fallen and falling trees

What problems do impaired streams cause?

Bank ErosionSediment Movement

2002

2002

1997

How does a stream become impaired?• Development or land use changes.

How does a stream become impaired?• Inappropriate agricultural and logging practices

How does a stream become impaired?

• Poor construction practices

How does a stream become impaired?

• Livestock impact

How does a stream become impaired?

• Roads, culverts and bridges

How does a stream become impaired?• Water impoundments and changes in water use

Irrigation

Impoundments

How do we reduce stream impairment?

• Maintain adequate riparian veg buffer• Low Impact Development (LID)• Livestock exclusion• Stream restoration

What is stream restoration?

• Recreating or modifying a stream channel to approximate a stable situation suited to the site and site conditions.

Channel Evolution(Succession)

Stream response to incising forces

Stream Corridor Restoration: Principles, Processes, and Practices. 1998. Federal Interagency Stream Restoration Working Group.

Why Do Stream Restoration?

• Water quality improvements

• Groundwater impact

• Habitat gains

• Ecosystem improvement

• Stop land loss

• Safety concerns reduced

• Less infrastructure damage

• Reduced flood damage

• Aesthetic improvments

Adventure Gut Demonstration Project

Adventure Gut demonstration project

• Basic design and background data• Determining bankful elevation• Locate and identify manmade constraints• (power lines, water lines sewage lines, etc.)• Plan for erosion and sediment control during

the project.

Adventure Gut Demonstration Project

Excavation begins with invasive removal

Adventure Gut Demonstration Project

Sadly, the necessary removal of a large mature tree

Adventure Gut demonstration project

Grading a new bankful level

Adventure Gut Demonstration Project

Adventure Gut Demonstration Project

Adventure Gut Demonstration Project

Adventure Gut Demonstration Project• Temporary bank stabilization

– Coir matting at toe of bank– Temporary seeding

Adventure Gut Demonstration Project

Adventure Gut Demonstration Project

Adventure Gut Demonstration Project

• Steep gully from field runoff– Geotextile liner– Stone sizing for stability

• Resetting the bridge for the nature trail.

Adventure Gut Demonstration Project

• REVEGETATION• This is the key step.• Plant selection and plant density• Early nursery notification• Proper planting methods• Plan for animal impact• Continuing invasive plant control

Adventure Gut Demonstration ProjectPerformance monitoring

• Fixed cross sections surveyed annually.

• Fixed photo points captured annually.

• Adjustments, repairs as required.

• Vegetation survival count annually.

• Exotics and invasive vegetation removed as required.

Adventure Gut Demonstration ProjectField Day

Adventure Gut Demonstration Project

August, 2009 during construction

Adventure Gut Demonstration Project

August, 2009 after planting

Adventure Gut Demonstration Project

April, 2010

Adventure Gut Demonstration Project

August, 2009 during construction

Adventure Gut Demonstration Project

August, 2009 during planting

Adventure Gut Demonstration Project

April, 2010

August, 2009 before construction

Adventure Gut Demonstration Project

August, 2009 before construction

Adventure Gut Demonstration Project

August, 2009 during construction

Adventure Gut Demonstration Project

August, 2009 during construction

Adventure Gut Demonstration Project

April, 2010

Adventure Gut Demonstration Project

Some issues unique to the Virgin Islands.

• Seasonal rainfall, dry season, wet season.• Dramatic rainfall shadow areas on each island.• Major flow events from hurricanes and intense

rainstorms.• Only intermittent streams, no perennial

streams.• Historic land use impacts are very large.• Thin clay soils are easily eroded.

What’s the next step?

• Reference streams• Public awareness• Find other impaired streams• Develop support coalitions• Funding sources• Investigate the appropriate selection of

native vegetation

For more information• USVI RC&D Council, Inc. www.usvircd.org/

• USDA NRCS National Engineering Handbook, Part 654 Stream Restoration Design

• Stream Corridor Restoration by the Federal Interagency Stream Corridor Restoration Working Group www.nrcs.usda.gov/technical/stream_restoration/

• Watershed Assessment of River Stability & Sediment Supply (WARSSS), http://www.epa.gov/warsss/

• NCSU BAE Stream Restoration Program www.bae.ncsu.edu/programs/extension/wqg/srp/

• Michael Shaffer, NCSU Bio and Ag Engr. Mike_Shaffer@ncsu.eduCampus Box 7612

Raleigh, NC 27695-7612

Thank you for your attention

Are there any questions?

Photo courtesy of Coral Bay Community Council