1. SOIL-CHOKED STONE KEYS WITH VEGETATION
By Dave Derrick,
Potomologist & VP,
River Research & Design, Inc.

2. KEY ALL STRUCTURES INTO THE BANK
KEY ALL STRUCTURES INTO THE BANK !!!! This includes bank protection, grade control, river training structures, everything!! Cheap insurance!! HERE ARE SOME FAILURES

3. THE KEY TO STABILITY IS THE KEY (stream should be on the other side of the wooden retard)

4. TOTAL FAILURE 2 YEARS AFTER BEING BUILT-9 Mile Run - April 2007
Flanked grade control structure. Water should flow over the structure (blue arrow), not around the end. Key way too short, does not go up to a higher elevation, & is not vegged. Blocky stone rarely works well in this application.
Key failure
“Based on the interagency publication, Stream Corridor Restoration: Principles, Processes, and Practices, this introductory training covers:
Stream corridor ecosystems and their components
Ecological processes, structure & functions
Characterization and analysis of stream corridors
Development of a restoration plan
Design, implementation, monitoring, and
Integrated, iterative, adaptive, flexible approaches”.
TOTAL FAILURE 2 YEARS AFTER BEING BUILT-9 Mile Run - April 2007

5. TOTAL FAILURE 2 YEARS AFTER BEING BUILT-9 Mile Run - April 2007
Flanked grade control structure. Water should be flowing over this structure, not around the end. Key way too short & not vegged.
“Based on the interagency publication, Stream Corridor Restoration: Principles, Processes, and Practices, this introductory training covers:
Stream corridor ecosystems and their components
Ecological processes, structure & functions
Characterization and analysis of stream corridors
Development of a restoration plan
Design, implementation, monitoring, and
Integrated, iterative, adaptive, flexible approaches”.
TOTAL FAILURE 2 YEARS AFTER BEING BUILT-9 Mile Run - April 2007

6. On the landward end (away from the stream), all keys need to go up the hill & tie into roughness (a forest). If no forest is available, one should be planted!!!

7. FAILURE-Looking DS @ flanked structure with massive bank erosion
“Based on the interagency publication, Stream Corridor Restoration: Principles, Processes, and Practices, this introductory training covers:
Stream corridor ecosystems and their components
Ecological processes, structure & functions
Characterization and analysis of stream corridors
Development of a restoration plan
Design, implementation, monitoring, and
Integrated, iterative, adaptive, flexible approaches”.
FAILURE-US AIR FORCE ACADEMY, CO.-PIX BY DERRICK-AUG 2010

8. FAILURE-US AIR FORCE ACADEMY, CO-PIX BY DERRICK-AUG 2010
FAILURE-Looking DS at total failure & active eroding bank. Whatever objects were put in the stream are flanked & destroyed.
“Based on the interagency publication, Stream Corridor Restoration: Principles, Processes, and Practices, this introductory training covers:
Stream corridor ecosystems and their components
Ecological processes, structure & functions
Characterization and analysis of stream corridors
Development of a restoration plan
Design, implementation, monitoring, and
Integrated, iterative, adaptive, flexible approaches”.
FAILURE-US AIR FORCE ACADEMY, CO-PIX BY DERRICK-AUG 2010

9. TOO STUPID – Looking US at gabion keyed inside culvert. Wrong
TOO STUPID – Looking US at gabion keyed inside culvert. Wrong. This gabion should butt up to the culvert header wall (to right, red outline).
“Based on the interagency publication, Stream Corridor Restoration: Principles, Processes, and Practices, this introductory training covers:
Stream corridor ecosystems and their components
Ecological processes, structure & functions
Characterization and analysis of stream corridors
Development of a restoration plan
Design, implementation, monitoring, and
Integrated, iterative, adaptive, flexible approaches”.
TOO STUPID - LONGFELLOW CR., SEATTLE, WA-DERRICK

10. A bank protection project should start & end in stable (usually depositional) areas.

11. FEMME CREEK, ST. LOUIS AREA, MO.
Protection starts late & ends early, resulting in erosion at both ends of project

12. A key has one main function: to connect bank protection works, or river training structures (Rock Vanes, Bendway Weirs, etc.), or grade control structures to the rest of the world, & not let the river “flank” (get behind or bypass) the structures.

13. Keys are best built of self-adjusting (well-graded), preferably self-filtering stone. If not self-filtering, a granular filter might be needed. Stone in the key can be the same used as bank paving or LPSTP. Keys could be built of large blocky stone that will not adjust (not recommended) & must be choked with smaller stone. Amount of stone in key should equal or exceed the amount of stone used per ft in the bank protection or river training structure.

14. Key designs for continuous bank protection.
20-30 degrees
Longitudinal Peaked Stone Toe Protection
Flow
Inner bank
Upstream key
Outer bank
20-30 degrees
Both the upstream & downstream keys should be angled 20 to 30 degrees to high flow. All stone keys are vegetated, soil-gravel-cobble choked, & overfilled 1.5 ft high with soil (will settle)
Downstream key
Tie-backs (blue lines) will connect the LPSTP to the key. The key, sometimes called the key root, is dug into the bank.
Mid-project keys (red lines) are perpendicular to high flow & connect the tie-back or LPSTP to the bank (the rest of the world)
Key designs for continuous bank protection.

15. On the landward end (away from the stream), all keys need to tie into roughness, or a higher elevation, or hopefully both!! Key crest elevation can be determined by flow elevation (Q-10, Q-100, etc.) or built to top bank, or to top bank & then a distance into the bank (termed a key root). On the Mississippi River key roots are dug 300 ft into the bank, Red River key root is a 100 ft long. Rule of thumb for small streams from Vicksburg Corps District : max. bank height plus max. scour depth = key root length

16. The downstream key on LPSTP in Reach 11, Harland Creek, Tchula, MS
The downstream key on LPSTP in Reach 11, Harland Creek, Tchula, MS., built The key is angled degrees to dominant (high) flow so that flow smoothly transitions & stream width smoothly expands, thus reducing the tendency for powerful recirculation to form (return currents). In this case deposition occurred DS of the key (bank protection for free)!!

17. Looking US on Harland Creek, Tchula, MS at smooth LPSTP (1
Looking US on Harland Creek, Tchula, MS at smooth LPSTP (1.5 tons/ft) with correctly angled downstream key with deposition (free bank protection) right where the photographer is standing. Installed Aug Pix Derrick 1996

18. The key itself should be heavily vegetated so as to slow flow velocities over the key. Slow water on the overbank means less chance of flanking. Vegetation is designed to act like a Living Dike & can be closely spaced adventitious rooting poles, or rooted stock plants, or container plants. In some cases the length of the key can be extended with vegetation alone, or other materials (buried anchored logs with veg).

19. Live Pole Planting Layout for all Keys.
Longitudinal Peaked Stone Toe Protection
Upstream key
Inner bank
Flow
Downstream key
All of the green lines delineate rows of adventitious live poles (willow, dogwood, etc.), planted deep & dense (typically 3 poles per linear ft.)
Adventitious Living Poles of appropriate species. As the key goes up in elevation, the pole species might have to be changed to a species preferring dryer conditions
Live Pole Planting Layout for all Keys.

20. The upstream key on Chenunda Creek, Wellsville NY
The upstream key on Chenunda Creek, Wellsville NY. The key is angled degrees to dominant (high) flow so if the thalweg of the stream meanders into the key, that key “nudges” the stream back into alignment. Never fight nature, it gets expensive when you do that !!

21. Key angle Pix by Derrick
Construction 9/19/ Looking US. Digging the US key at a 20 to 30 degree angle to where if the stream meanders toward the key, the high flow might attack the key
Key angle
High flow angle
Pix by Derrick

22. Looking US. Hoe placing big stone (NYS DOT heavy) in US keyway
Looking US. Hoe placing big stone (NYS DOT heavy) in US keyway. Medium & small stone will be added as a choke.
Pix by Derrick

23. Construction 9/20/2006. Looking at angle of key to stream flow
Construction 9/20/ Looking at angle of key to stream flow. More stone will be added & then soil choked so the landowner can grow a lawn.
High flow angle
Key angle
Pix by Derrick

24. Harvesting Pole-sized Adventitious Rooting Material for the Key
“Based on the interagency publication, Stream Corridor Restoration: Principles, Processes, and Practices, this introductory training covers:
Stream corridor ecosystems and their components
Ecological processes, structure & functions
Characterization and analysis of stream corridors
Development of a restoration plan
Design, implementation, monitoring, and
Integrated, iterative, adaptive, flexible approaches”.

25. CONSTRUCTION-TOLEDO OHIO PROJECTS. PIX BY KRIS PATTERSON 8-2008
Matt Horvat with safety glasses & ear plugs cutting willows with chainsaw
“Based on the interagency publication, Stream Corridor Restoration: Principles, Processes, and Practices, this introductory training covers:
Stream corridor ecosystems and their components
Ecological processes, structure & functions
Characterization and analysis of stream corridors
Development of a restoration plan
Design, implementation, monitoring, and
Integrated, iterative, adaptive, flexible approaches”.
CONSTRUCTION-TOLEDO OHIO PROJECTS. PIX BY KRIS PATTERSON

26. Renewable resource-willow will grow back multi-stem after cutting
“Based on the interagency publication, Stream Corridor Restoration: Principles, Processes, and Practices, this introductory training covers:
Stream corridor ecosystems and their components
Ecological processes, structure & functions
Characterization and analysis of stream corridors
Development of a restoration plan
Design, implementation, monitoring, and
Integrated, iterative, adaptive, flexible approaches”.
CONSTRUCTION-TOLEDO OHIO PROJECTS. PIX BY KRIS PATTERSON

27. Poles ready to have leaves & side branches removed.
“Based on the interagency publication, Stream Corridor Restoration: Principles, Processes, and Practices, this introductory training covers:
Stream corridor ecosystems and their components
Ecological processes, structure & functions
Characterization and analysis of stream corridors
Development of a restoration plan
Design, implementation, monitoring, and
Integrated, iterative, adaptive, flexible approaches”.
CONSTRUCTION-TOLEDO OHIO PROJECTS. PIX BY KRIS PATTERSON

28. Teen volunteers cutting side branches & leaves from poles
“Based on the interagency publication, Stream Corridor Restoration: Principles, Processes, and Practices, this introductory training covers:
Stream corridor ecosystems and their components
Ecological processes, structure & functions
Characterization and analysis of stream corridors
Development of a restoration plan
Design, implementation, monitoring, and
Integrated, iterative, adaptive, flexible approaches”.
CONSTRUCTION-TOLEDO OHIO PROJECTS. PIX BY KRIS PATTERSON

29. CONSTRUCTION-TOLEDO OHIO PROJECTS. PIX BY KRIS PATTERSON 8-2008
Use stout twine to bind a set number of poles into a manageable bundle. Twine should be looped & tied at one end, then looped & tied at the opposite end, thus providing a carrying handle
“Based on the interagency publication, Stream Corridor Restoration: Principles, Processes, and Practices, this introductory training covers:
Stream corridor ecosystems and their components
Ecological processes, structure & functions
Characterization and analysis of stream corridors
Development of a restoration plan
Design, implementation, monitoring, and
Integrated, iterative, adaptive, flexible approaches”.
CONSTRUCTION-TOLEDO OHIO PROJECTS. PIX BY KRIS PATTERSON

30. CONSTRUCTION-TOLEDO OHIO PROJECTS. PIX BY KRIS PATTERSON 8-2008
Soaking willow, half out of water, half of the pole should be submerged with butt ends underwater. Research by Dr. Doug Shields showed that soaking Black Willow 10 days will increase root production by 2,600%, 100% flushed out, & twice as many survived. Fence is to protect from beaver browse.
“Based on the interagency publication, Stream Corridor Restoration: Principles, Processes, and Practices, this introductory training covers:
Stream corridor ecosystems and their components
Ecological processes, structure & functions
Characterization and analysis of stream corridors
Development of a restoration plan
Design, implementation, monitoring, and
Integrated, iterative, adaptive, flexible approaches”.
CONSTRUCTION-TOLEDO OHIO PROJECTS. PIX BY KRIS PATTERSON

31. Dump truck load level full of Sandbar & Streamco Willow, & Ruby Red osier dogwood, (1,500 poles total).
Pix by Derrick

32. MID-PROJECT KEYS FOR CONTINUOUS PROTECTION MEASURES & KEYS FOR REDIRECTIVE TECHNIQUES, ARE ALMOST ALWAYS ORIENTED PERPENDICULAR TO THE BANK (& roughly to high flow).

33. A MID-PROJECT LIVING KEY ON CHENUNDA CREEK Vegetated & soil-choked stone key is perpendicular to high flow (& the bank)

34. Cross-section for keyway
Detail for key
Cross-section for keyway
Flow

35. Place granular filter if not using a self-filtering stone
Detail for key
Flow
Place granular filter if not using a self-filtering stone

36. Place Willow Poles against one or both sides of trench
Detail for key
Place Willow Poles against one or both sides of trench
Flow
Make sure the butt ends of poles are either in the water or in the capillary (or vadose) zone (all the way to the bottom).

37. Construction 9/19/ Digging a mid-project key perpendicular to the bank. Some veg (willow poles) in place
Pix by Derrick

38. Place soil to cover at least the butt ends of the poles
Detail for key
Place soil to cover at least the butt ends of the poles
Flow

39. Detail for key
Place stone in trench
Flow

40. Construction 9/19/2006. Looking @ key
Construction 9/19/2006. key. Butt ends of willow & dogwood poles down deep. Some large stone placed, needs choke stone.
Pix by Derrick

41. Choke stone with gravel-cobble (white areas) & water in
Detail for key
Choke stone with gravel-cobble (white areas) & water in
Flow

42. Detail for key
Backfill and overfill with native soils, then compact (some settling will still occur)
Flow

43. Construction 9/21/2006. Key stone is now soil-gravel choked.
Pix by Derrick

44. Detail for key
Seed
Flow
DONE

45. 13 MONTHS LATER-low flow. Veg in key is robust.
Pix by Derrick 10/15/2007
13 MONTHS LATER-low flow. Veg in key is robust.

46. 2 YEARS 9 MONTHS AFTER CONSTRUCTION-CHENUNDA CR.-DERRICK 6-18-09
2.75 YEARS LATER-Lush growth from 2 rows of live poles on mid-project key.
2 YEARS 9 MONTHS AFTER CONSTRUCTION-CHENUNDA CR.-DERRICK

47. VEGETATION IN KEY ACTING AS A LIVING DIKE ON ONONDAGA CREEK (Veg oriented perpendicular to high flow)

48. Looking toward stream. Key vegetation is 4 ft deep
Looking toward stream. Key vegetation is 4 ft deep. Key stone buried to right of veg.
Onondaga Nichol Road Bridge, LaFayette, NY – project planted
Pix by Derrick

49. July 10, {middle of second growing season} Key vegetation is over 7 ft tall. Willow & dogwood. Will act as a Living Dike.
Onondaga Creek-Year 2
Pix by Derrick

50. DESIGN CONSIDERATIONS FOR LPSTP KEYS
LPSTP must be deeply keyed into the bank at both the upstream and downstream ends and at regular intervals along its entire length. Charlie Elliott’s spacing rules-of-thumb for keys in flat-sloped sand bed water bodies: 50 to 100 ft intervals on smaller streams, 1 to 2 bankfull widths on larger waterways.
Keys at the upstream and downstream ends of LPSTP should not be at a 90 degree angle to the LPSTP structure, but at 20 to 30 degrees to HIGH FLOW.
Keys should go far enough back into the river bank so river migration will not flank the key & the LPSTP. Analyze the meander belt width of the stream or river to determine if the key can get flanked.
Keys should be vegetated if possible. Key length can be extended with vegetation alone in some cases.
Volume of material per ft of key should equal or exceed the volume of material per ft in the LPSTP
Minimum key width should be two times the D-100 of the stone used

51. TURKEY CREEK, KANSAS CITY, MO –PIX BY DERRICK-2/5/2009
A short one-stone 90 degree key at the US end of the stacked stone wall. With erosion US, flanking is imminent.
Attack flow
TURKEY CREEK, KANSAS CITY, MO –PIX BY DERRICK-2/5/2009

52. This PowerPoint presentation was developed & built by Dave Derrick
This PowerPoint presentation was developed & built by Dave Derrick. Any questions or comments or improvements, call my personal , or Enjoy the information!!
“Based on the interagency publication, Stream Corridor Restoration: Principles, Processes, and Practices, this introductory training covers:
Stream corridor ecosystems and their components
Ecological processes, structure & functions
Characterization and analysis of stream corridors
Development of a restoration plan
Design, implementation, monitoring, and
Integrated, iterative, adaptive, flexible approaches”.

53. NAP TIME FOR CLEOPHUS !!!