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Stream Restoration Stream Restoration Techniques Techniques Channel Geometry Design and Construction Streamside / Slope Protection Instream Structures

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Page 1: Stream Restoration Techniques  Channel Geometry Design and Construction  Streamside / Slope Protection  Instream Structures

Stream Restoration Stream Restoration TechniquesTechniques

Channel Geometry Design and Construction

Streamside / Slope Protection

Instream Structures

Page 2: Stream Restoration Techniques  Channel Geometry Design and Construction  Streamside / Slope Protection  Instream Structures

Stream Restoration Stream Restoration TechniquesTechniques

Channel Geometry Design and Construction

Objectives: Achieve a Stable Channel Geometry

Bankful Channel Width and DepthSinuositySlope

Page 3: Stream Restoration Techniques  Channel Geometry Design and Construction  Streamside / Slope Protection  Instream Structures

Views of a Views of a RiverRiver

Cross-Sectional View (Dimension)

Plan View (Pattern)

Longitudinal View (Profile)

Page 4: Stream Restoration Techniques  Channel Geometry Design and Construction  Streamside / Slope Protection  Instream Structures
Page 5: Stream Restoration Techniques  Channel Geometry Design and Construction  Streamside / Slope Protection  Instream Structures

Stream Restoration Stream Restoration TechniquesTechniques

Streamside / Slope Protection

Objectives: Restore a Functional Riparian Zone

Stabilize Banks Provide shadingFilter sediments

Page 6: Stream Restoration Techniques  Channel Geometry Design and Construction  Streamside / Slope Protection  Instream Structures

Stream Restoration Stream Restoration TechniquesTechniques

Streamside / Slope Protection

Considerations: Native SpeciesMaterials (hard vs soft)Climate / Soils / Expected InundationWildlife UsesTiming

Page 7: Stream Restoration Techniques  Channel Geometry Design and Construction  Streamside / Slope Protection  Instream Structures

Streamside / Slope ProtectionTECHNIQUESTECHNIQUES FUNCTIONAL APPLICATIONFUNCTIONAL APPLICATION

1. Bank Shaping and Plantings1. Bank Shaping and Plantings Bank stabilization, erosion control, promote vegetative growth, riparian habitatBank stabilization, erosion control, promote vegetative growth, riparian habitat

2. Joint Plantings2. Joint Plantings Bank stabilization, erosion control, promote vegetative growth, riparian habitatBank stabilization, erosion control, promote vegetative growth, riparian habitat

3. Imbricated Riprap3. Imbricated Riprap Bank stabilization, erosion controlBank stabilization, erosion control

4. Vegetated Gabions4. Vegetated Gabions Bank stabilization, erosion controlBank stabilization, erosion control

5. Dormant Post Plantings5. Dormant Post Plantings Bank stabilization, erosion control, promote vegetative growth, riparian habitatBank stabilization, erosion control, promote vegetative growth, riparian habitat

6. Live Stakes6. Live Stakes Bank stabilization, erosion control, promote vegetative growth, riparian habitatBank stabilization, erosion control, promote vegetative growth, riparian habitat

7. Live Fascines7. Live Fascines Bank stabilization, erosion control, promote vegetative growth, riparian habitatBank stabilization, erosion control, promote vegetative growth, riparian habitat

8. Natural Fiber Roles8. Natural Fiber Roles Bank stabilization, erosion control, promote vegetative growth, riparian habitatBank stabilization, erosion control, promote vegetative growth, riparian habitat

9. Brush Mattresses9. Brush Mattresses Bank stabilization, erosion control, promote vegetative growth, riparian habitatBank stabilization, erosion control, promote vegetative growth, riparian habitat

10. Live Crib Walls10. Live Crib Walls Bank stabilization, erosion controlBank stabilization, erosion control

11. Log, Rootwad, and Boulder 11. Log, Rootwad, and Boulder RevetmentsRevetments Bank stabilization, erosion control, instream habitatBank stabilization, erosion control, instream habitat

12. Tree Revetments12. Tree Revetments Bank stabilization, erosion control, instream habitatBank stabilization, erosion control, instream habitat

13. Riparian Forest Buffers13. Riparian Forest Buffers everythingeverything

Page 8: Stream Restoration Techniques  Channel Geometry Design and Construction  Streamside / Slope Protection  Instream Structures

• Appropriate where there is a lack of desired vegetative cover on the face of existing or required rock riprap.

• Root systems provide a mat upon which the rock riprap rests and prevents loss of fines from the underlying soil base.

• Root systems also improve drainage in the soil base.

• Will quickly establish riparian vegetation.

• Should, where appropriate, be used with other soil bioengineering systems and vegetative plantings to stabilize the upper bank and ensure a regenerative source of streambank vegetation.

• Have few limitations and can be installed from base flow levels to top of slope, if live stakes are installed to reach ground water.

Live stakes taped into joints or openings between rock which have previously been installed on a slope or while rock is being placed on the slope face.

• Survival rates can be low due to damage to the cambium or lack of soil/ stake interface.

• Thick rock riprap layers may require special tools for establishing pilot holes.

Applications and Effectiveness

Page 9: Stream Restoration Techniques  Channel Geometry Design and Construction  Streamside / Slope Protection  Instream Structures

• Provide protection to the streambank in areas with near vertical banks where bank sloping options are limited.

• Afford a natural appearance, immediate protection and accelerate the establishment of woody species.

• Effective on outside of bends of streams where high velocities are present.

• Appropriate above and below water level where stable streambeds exist.

• Don’t adjust to toe scour.

• Can be complex and expensive.

• Should, where appropriate, be used with soil bioengineering systems and vegetative plantings to stabilize the upper bank and ensure a regenerative source of streambank vegetation.

Hollow, box-like interlocking arrangements of untreated log or timber members filled above baseflow with alternate layers of soil material and live branch cuttings that root and gradually take over the structural functions of the wood members.

Applications and Effectiveness

Page 10: Stream Restoration Techniques  Channel Geometry Design and Construction  Streamside / Slope Protection  Instream Structures

• Will tolerate high boundary shear stress if logs and rootwads are well anchored.

• Suited to streams where fish habitat deficiencies exist.

• Should, where appropriate, be uses with soil bioengineering systems and vegetative plantings to stabilize the upper bank and ensure a regenerative source of streambank vegetation.

• Will give limited life depending on climate and tree species used. Some species, such as cottonwood or willow, often sprout and accelerate colonization.

• Might need eventual replacement if colonization does not take place or soil bioengineering systems are not used.

• Use of native materials can sequester sediment and woody debris, restore streambanks in high velocity streams, and improve fish rearing and spawning habitat.

• Site must be accessible to heavy equipment.

• Materials might not be readily available at some locations.

• Can create local scour and erosion.

• Can be expensive.

Boulders and logs with root masses attached placed in and on streambanks to provide streambank erosion, trap sediment, and improve habitat diversity.

Applications and Effectiveness

Page 11: Stream Restoration Techniques  Channel Geometry Design and Construction  Streamside / Slope Protection  Instream Structures

Charles N. Greene

Page 12: Stream Restoration Techniques  Channel Geometry Design and Construction  Streamside / Slope Protection  Instream Structures
Page 13: Stream Restoration Techniques  Channel Geometry Design and Construction  Streamside / Slope Protection  Instream Structures

BioengineeringBioengineering

Charles N. Greene

Page 14: Stream Restoration Techniques  Channel Geometry Design and Construction  Streamside / Slope Protection  Instream Structures
Page 15: Stream Restoration Techniques  Channel Geometry Design and Construction  Streamside / Slope Protection  Instream Structures
Page 16: Stream Restoration Techniques  Channel Geometry Design and Construction  Streamside / Slope Protection  Instream Structures

Stream Restoration Stream Restoration TechniquesTechniques

Instream Structures

Objectives: Maintain efficient sediment transport and channel geometryProtect vulnerable banksDirect flow towards or away from critical areas (e.g., road grade, bridge abutment)Create natural hydraulic channel unitsRestore habitat complexity

Page 17: Stream Restoration Techniques  Channel Geometry Design and Construction  Streamside / Slope Protection  Instream Structures

Stream Restoration Stream Restoration TechniquesTechniques

Instream Structures

Considerations: Overall Design

Appropriate Materials (size and type)Placement Location

MachineryTiming of Construction

Page 18: Stream Restoration Techniques  Channel Geometry Design and Construction  Streamside / Slope Protection  Instream Structures

Instream StructuresInstream StructuresTECHNIQUESTECHNIQUES FUNCTIONAL APPLICATIONFUNCTIONAL APPLICATION

1. Boulder Clusters1. Boulder Clusters protect stream bed, instream habitat, channel complexityprotect stream bed, instream habitat, channel complexity

2. Log and Rock Vanes2. Log and Rock Vanes protect stream bed, bank erosion control, instream habitat, channel protect stream bed, bank erosion control, instream habitat, channel complexitycomplexity

3. J-Hook Vanes3. J-Hook Vanes protect stream bed, bank erosion control, instream habitat, channel protect stream bed, bank erosion control, instream habitat, channel complexitycomplexity

4. W-Weirs4. W-Weirs protect stream bed, bank erosion control, instream habitat, channel protect stream bed, bank erosion control, instream habitat, channel complexitycomplexity

6. Rootwad / Logvane / J-Hook 6. Rootwad / Logvane / J-Hook Combo Combo

protect stream bed, bank erosion control, instream habitat, channel protect stream bed, bank erosion control, instream habitat, channel complexitycomplexity

5. Stream Deflectors5. Stream Deflectors bank erosion control, instream habitat, channel complexitybank erosion control, instream habitat, channel complexity

6. Tree Kickers6. Tree Kickers bank erosion control, instream habitat, channel complexitybank erosion control, instream habitat, channel complexity

7. Log / Rock Check Dams7. Log / Rock Check Dams protect stream bed, instream habitat, channel complexityprotect stream bed, instream habitat, channel complexity

8. Log Sills / Check Dams8. Log Sills / Check Dams protect stream bed, instream habitat, channel complexityprotect stream bed, instream habitat, channel complexity

9. Step Pools9. Step Pools protect stream bed, instream habitat, channel complexityprotect stream bed, instream habitat, channel complexity

10. Lunker Structures10. Lunker Structures instream habitat, channel complexityinstream habitat, channel complexity

11. Stream Meander Restoration11. Stream Meander Restoration protect stream bed, bank erosion control, instream habitat, channel protect stream bed, bank erosion control, instream habitat, channel complexitycomplexity

12. Hydraulic Connection 12. Hydraulic Connection RestorationRestoration

protect stream bed, bank erosion control, instream habitat, channel protect stream bed, bank erosion control, instream habitat, channel complexitycomplexity

Page 19: Stream Restoration Techniques  Channel Geometry Design and Construction  Streamside / Slope Protection  Instream Structures

Groups of boulders placed in the base flow cannel to provide cover,create scour holes, or areas of reduced velocity.

Applications and Effectiveness

• Can be used in most stream habitat types including riffles, runs, flats, glides and open pools.

• Greatest benefits are realized in streams with average flows exceeding 2 feet per second.

• Group placement of these boulders are desirable in larger streams. Whereas single boulder placement in smaller streams might have the same effect.

• Boulder clusters are most effective in wide, shallow streams with gravel or rubble beds.

• Also useful in deeper streams for providing cover and improving substrate.

• Not recommended for sand bed (and smaller bed materials) streams because they tend to get buried.

• Added erosive forces might cause channel and bank failures.

• Not recommended for streams which are aggrading or degrading.

• May promote bar formation in streams with high bed material.

Page 20: Stream Restoration Techniques  Channel Geometry Design and Construction  Streamside / Slope Protection  Instream Structures

• Appropriate along outside bends of streams where water depths can be maintained at or above the top of the structure.

• Suited to streams where fish habitat deficiencies exist.

• Should, where appropriate, be used with soil bioengineering systems and vegetative plantings to stabilize the upper bank and ensure a regenerative source of streambank vegetation.

• Are often used in conjunction with wing deflectors and weirs to direct and manipulate flows.

• Are not recommended for streams with heavy bed material loads.

• Most commonly used in streams with gravel-cobble beds.

• Heavy equipment may be necessary for excavating and installing the materials.

• Can be expensive.

Cell constructed of heavy wooden planks ad blocks which are imbedded into the toe of streambanks at channel bed level to provide covered compartments for fish shelters, habitat, and prevention of streambank erosion.

Applications and Effectiveness

Page 21: Stream Restoration Techniques  Channel Geometry Design and Construction  Streamside / Slope Protection  Instream Structures

• Should be designed and located far enough downstream from riffle areas to avoid backwater effects that would drown out or otherwise damage the riffle.

• Should be sized based on anticipated scour.

• The material washed out of scour holes is usually deposited a short distance downstream to form a bar or riffle area. These areas of deposition are often composed of clean gravels that provide excellent habitat for certain species.

• Can be installed in series on alternative streambanks to produce a meandering thalweg and associated structural diversity.

• Rock and rock-filled log crib deflector structures are most common.

• Should be used in channels with low physical habitat diversity, particularly those with a lack of stable pool habitat.

• Deflectors placed in sand bed streams may settle or fail due to erosion sand, and in these areas a filter layer or geotextile might be needed underneath the deflector.

Structures that protrude from either streambank to provide overhead cover, aquatic organism substrate and habitat, stream current deflection, scouring, deposition, and drift catchment.

Applications and Effectiveness

Page 22: Stream Restoration Techniques  Channel Geometry Design and Construction  Streamside / Slope Protection  Instream Structures
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Page 26: Stream Restoration Techniques  Channel Geometry Design and Construction  Streamside / Slope Protection  Instream Structures

Rock Vane

W Weir

Page 27: Stream Restoration Techniques  Channel Geometry Design and Construction  Streamside / Slope Protection  Instream Structures
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Page 30: Stream Restoration Techniques  Channel Geometry Design and Construction  Streamside / Slope Protection  Instream Structures

Photo 7/ 8 0025Photo 7/ 8 0025UTM 451341mEUTM 451341mE

4150501mN4150501mN

Indian Crk., Rt 16, S of Indian Crk., Rt 16, S of Woosley, Woosley, Wyoming Co., 8 July 2002Wyoming Co., 8 July 2002

S. Kite Photo