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RANDOM BOULDER FIELDS {RBF} (For bank protection) 2 EXAMPLES

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Presentation on theme: "RANDOM BOULDER FIELDS {RBF} (For bank protection) 2 EXAMPLES"— Presentation transcript:

1 RANDOM BOULDER FIELDS {RBF} (For bank protection) 2 EXAMPLES

2 Typically a Random Native Boulder Field is built in-channel adjacent to the bank of concern to strengthen that area, increase hydraulic roughness, increase turbulence, partially block flow, decrease flow velocities, dissipate energy, & shift velocities & the thalweg toward the center of the stream. RBF increase habitat diversity, & can increase aeration & dissolved oxygen. Aesthetics can be anywhere from natural appearing to soothing & stupendous!!

3 Taking the classic concept of making the bank of concern hydraulically rougher & tougher, & the opposite bank smoother & weaker, the RBF also increases the bed roughness near the bank of concern!!!

4 By the stream dream team
POPLAR RIVER, LUTSEN, MN. SEPARATING THE MEGA-SLIDE FROM THE RIVER (AND MORE) By the stream dream team

5 Stream stabilization/restoration: Conceptually we will separate the stream from the 90+ ft tall hill, & in the channel we will make the inside of the bend smoother & the outer section of the bend & bank hydraulically rougher & tougher.

6 PRE-PROJECT PHOTOS by Dave Derrick AUGUST 13, 2007 (Lowest flow in almost 30 years)

7 From top of mega slump looking US
From top of mega slump looking US. In some sections the outer section of the channel was smooth & inner section boulder strewn, that will be reversed!!! Derrick lowest flow in 30 yrs

8 THE PLAN “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”.

9 Stream Project Functions:
Bendway Weirs move scour & the thalweg away from attacked bank, with velocities reduced within weir field & on bank. Randomly placed native boulder field increases roughness, increases turbulence & complexity, & decreases flow velocities. Vegetation roughness reduces near-bank flow velocities. Roots strengthen bank & bind soil. Mini-swale captures colluvium. “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”.

10 Not shown on the next slide, but a Random Boulder Field (RBF) will be installed within the Bendway Weir field.

11 Mega- Slump Stream Project Planform
Keys Boulder Revetment Mega- Slump Stream Project Planform Bendway Weir Pre-dug Scour Holes Mini Swale Bridge Transplanted Veg

12 CONSTRUCTION-POPLAR RIVER @ MEGA-SLUMP-PIX BY DERRICK 8/5-8/2008
A couple pebbles to be used for the keys & Bendway Weirs. Boulder specifications: D-100: max 54 inches, min 40 inches; D-50: max 38 inches, min 32 inches; D-35: max. 28 inches, min 22 inches. “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-POPLAR MEGA-SLUMP-PIX BY DERRICK 8/5-8/2008

13 CONSTRUCTION PHOTOS by Dave Derrick and Jay Michels AUGUST 5-8, 2008

14 CONSTRUCTION-POPLAR RIVER @ MEGA-SLUMP-PIX BY DERRICK 8/5-8/2008
Looking constructed mini-weir & Bendway Weir #1. Note constructed boulder field & pool riffle-pool complex on right side of channel “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-POPLAR MEGA-SLUMP-PIX BY DERRICK 8/5-8/2008

15 CONSTRUCTION PIX OF RANDOM SCATTERING OF BOULDERS TO CREATE THE BOULDER FIELDS BETWEEN THE BENDWAY WEIRS “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”.

16 Looking DS @ boulder flying though air
“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-POPLAR MEGA-SLUMP-PIX BY DERRICK 8/5-8/2008

17 Looking DS @ the big boulder splash
“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-POPLAR MEGA-SLUMP-PIX BY DERRICK 8/5-8/2008

18 Looking DS @ 2 more boulders flying though air
“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-POPLAR MEGA-SLUMP-PIX BY DERRICK 8/5-8/2008

19 CONSTRUCTION-POPLAR RIVER @ MEGA-SLUMP-PIX BY DERRICK 8/5-8/2008
Looking completed boulder field & Bendway Weir & stone toe & Jay. Does it look natural???? I would say so… Smooth on inside of bend “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-POPLAR MEGA-SLUMP-PIX BY DERRICK 8/5-8/2008

20 Stream Project Functions::::::::
Longitudinal toe stone provides scour protection Toe stone protection completely separates stream from Mega Slump Willow poles provide vegetative roughness, increase height of “soft protection”, shades stone & water, & has many wildlife functions {everything from carbon input to structure cover to insect production, beneficial to pollinators, etc.} Mini-Swale provides a storage area for colluvium from Mega Slump Bendway Weirs increase stream roughness, reduce toe scour, provide diversity & complexity of depth, velocity (horizontal & vertical) & substrate, plus they move the thalweg away from the toe of the eroding bank. The dug pools at the ends of the Bendway Weirs provide mini pool-riffle-pool sequences throughout the bend. Boulder fields provide additional roughness, plus a “natural” look

21 CONSTRUCTION COMPLETE (going from upstream to downstream) Photos by Dave Derrick AUGUST 8, 2008

22 Looking DS. Boulder field to left, dug pools & riffles on right
CONSTRUCTION COMPLETE-POPLAR MEGA-SLUMP-PIX BY DERRICK

23 CONSTRUCTION-POPLAR RIVER @ MEGA-SLUMP-PIX BY DERRICK 8/5-8/2008
Looking constructed mini-weir & Bendway Weir #1. Note constructed boulder field & pool riffle-pool complex on right side of channel “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-POPLAR MEGA-SLUMP-PIX BY DERRICK 8/5-8/2008

24 Looking DS @ toe stone & Bendway Weirs 2 - 4.
BW#4 BW#3 BW#2 CONSTRUCTION COMPLETE-POPLAR MEGA-SLUMP-PIX BY DERRICK

25 Looking DS @ Bendway Weirs # 4 & 5. Diversity & complexity of flow
CONSTRUCTION COMPLETE-POPLAR MEGA-SLUMP-PIX BY DERRICK

26 CONSTRUCTION COMPLETE-POPLAR R. @ MEGA-SLUMP-PIX BY DERRICK 8-8-2008
Looking at constructed natural appearing random boulder field (foreground) & random chaotic stone toe CONSTRUCTION COMPLETE-POPLAR MEGA-SLUMP-PIX BY DERRICK

27 Looking US @ pool & colorful boulder assemblage.
CONSTRUCTION COMPLETE-POPLAR MEGA-SLUMP-PIX BY DERRICK

28 Watching the river flow, looking US @ Bendway Weir #5 & boulder field
CONSTRUCTION COMPLETE-POPLAR MEGA-SLUMP-PIX BY DERRICK

29 CONSTRUCTION COMPLETE-POPLAR R. @ MEGA-SLUMP-PIX BY DERRICK 8-8-2008
Watching the river flow, looking BW #5 & boulder field, fantastic diversity of depth, velocity, turbulence, substrate, holding water (refugia) CONSTRUCTION COMPLETE-POPLAR MEGA-SLUMP-PIX BY DERRICK

30 Looking US @ placed boulders dissipating stream energy
CONSTRUCTION COMPLETE-POPLAR MEGA-SLUMP-PIX BY DERRICK

31 Looking DS @ stone toe, boulder field, & Bendway Weirs 7 & 8.
CONSTRUCTION COMPLETE-POPLAR MEGA-SLUMP-PIX BY DERRICK

32 CONSTRUCTION COMPLETE-POPLAR R. @ MEGA-SLUMP-PIX BY DERRICK 8-8-2008
Looking Bendway Weir #7 & stone toe, smooth on inside of bend, rough on outside of bend. CONSTRUCTION COMPLETE-POPLAR MEGA-SLUMP-PIX BY DERRICK

33 CONSTRUCTION COMPLETE-POPLAR R. @ MEGA-SLUMP-PIX BY DERRICK 8-8-2008
Looking Key #8 (with veg) & BW #8. Note pools & flow at end of weir CONSTRUCTION COMPLETE-POPLAR MEGA-SLUMP-PIX BY DERRICK

34 Looking DS @ stone toe, boulder field, & Bendway Weirs 7 & 8.
CONSTRUCTION COMPLETE-POPLAR MEGA-SLUMP-PIX BY DERRICK

35 SITE 4: MINIMAL BANK STABILIZATION TO REDUCE THE SEDIMENT LOAD INTO DINGMANS CREEK FROM THE SMALL SLIDE DELAWARE WATER GAP NATIONAL RECREATION AREA, NATIONAL PARK SERVICE PROJECT CONSTRUCTED SEPTEMBER 24, 2009

36 PROBLEMS For approximately 200 ft Dingmans Creek is flowing against & eroding the left valley wall (estimated height 35 ft). The amount of fine sediment delivered to the stream is significant. This entire colluvium slide is very unstable. If erosion progresses at this site it may kick the stream back toward the park road downstream and create a threat to road stability (Johnny B. Mountain Road). The point bar (right side) of the channel is very rough with a number of boulders increasing the hydraulic roughness & impeding flow.

37 METHODS EMPLOYED 35 Vegetated Traffic Control Stones (TCS)
Every 4th TCS is keyed 10 ft into the bank (perpendicular) with rooted Black Willow whips & other live poles planted at a rate of 3 plants per ft. Every 4th TCS has a Single Stone Bendway Weir (SSBW) to move the thalweg away from the left bank & toward the center of the channel approximately 5-8 ft. The space between & behind the TCS is heavily vegetated with a variety of species of rooted-stock trees & shrubs. The loose eroding talus slope slide was heavily planted with several species of rooted-stock shrubs & trees Native boulders from the point bar were placed as a random boulder field streamward of the TCS & SSBW.

38 PRE-PROJECT PHOTOS by Dave Derrick (HIGH WATER)

39 HIGH WATER-Looking DS @ fast water (smoother bed) near bank.
PRE-PROJECT DINGMANS CR-SITE 4 PIX BY DERRICK

40 PRE-PROJECT DINGMANS CR-SITE 4 PIX BY DERRICK 7-24-2008
HIGH WATER-Looking smoother bed near bank, rougher toward inside of bend!! PRE-PROJECT DINGMANS CR-SITE 4 PIX BY DERRICK

41 PRE-PROJECT DINGMANS CR-SITE 4 PIX BY DERRICK 12-15-2008
HIGH WATER-Looking project bank. Erosion of bank is contributing significant sediment to the system. Bed is rough on the inside of the bend, but smooth near eroding bank PRE-PROJECT DINGMANS CR-SITE 4 PIX BY DERRICK

42 PRE-PROJECT DINGMANS CR-SITE 4 PIX BY DERRICK 12-15-2008
HIGH WATER-Looking DS toward DS end of project, smoother bed near bank, rougher toward inside of bend!! PRE-PROJECT DINGMANS CR-SITE 4 PIX BY DERRICK

43 SOLUTIONS (THE PLAN) This project is designed to stabilize 200 ft of the bank at the present location by increasing roughness of the entire bank with 3 gallon container rooted-stock trees & shrubs. Hard protection is limited to the toe & includes 35 vegetated Traffic Control Stones (TCS). TCS were typically 3 ft by 3 ft by 4 ft & spaced 3 to 6 ft apart. Every 4th TCS was keyed 8 to 10’ into the bank & had a Single-Stone Bendway Weir (SSBW) placed at the stream end. Live poles were placed in the key trench before stone was placed. Eight SSBW were built. A random natural bedload boulder field was placed around & in front of the SSBW & TCS’s.

44 Courtesy of Ecological Restoration, Inc
“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”.

45 Courtesy of Ecological Restoration, Inc.
Correction: There should be 3 Traffic Control Stones between each Single Stone Bendway Weir, not 2. Courtesy of Ecological Restoration, Inc. “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”.

46 Courtesy of Ecological Restoration, Inc.
TCS SSBW 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”. Courtesy of Ecological Restoration, Inc.

47 Two healthy Single Stone Bendway Weir (SSBW) stones.
“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 DINGMANS CR-SITE 4 PIX BY DERRICK

48 PLANTS PLANTED Common Name # Size Gray Birch 50 2 gallon pots
Gray Birch unrooted poles Buttonbush bare root Silky Dogwood bare root Ninebark bare root Rhododendron gallon pots White Pine gallon pots

49 Key Traffic Control Stones (TCS) with Single Stone Bendway Weirs (SSBW) & vegged keys & pole plantings Key Key Key TCS TCS TCS Key TCS TCS Key TCS SSBW TCS TCS SSBW Key Thalweg TCS SSBW Traffic Control Stones (TCS) sized about 3 ft by 3 ft by 4 ft, dug into the bed & bank, designed to stabilize & roughen the bank, are spaced 3 to 6 ft apart. Every 4th TCS is keyed into the bank & has a Single Stone Bendway Weir attached. 8 SSBW total

50 Scoop a hole into the bed & bank for the Traffic Control Stone (TCS), then place live poles against bank, push the TCS into position, then backfill. TCS were typically 3 ft by 3 ft by 4 ft & spaced 3 to 6 ft apart. Every 4th TCS was keyed 8 to 10’ into the bank & had a Single-Stone Bendway Weir (SSBW) placed at the stream end. Live poles were placed in the key trench before stone was placed. A random natural bedload boulder field was placed around & in front of the SSBW & TCS’s. All bare areas of the slide area were planted with 3 gallon container rooted-stock trees & shrubs.

51 Key Key Key TCS TCS TCS Key TCS TCS Key TCS SSBW TCS TCS SSBW Key Thalweg TCS SSBW Rooted–stock container shrubs & trees added to Traffic Control Stones at toe & all bare areas of the entire eroding bank

52 CONSTRUCTION PHOTOS by Dave Derrick, September 19-20, 2009

53 CONSTRUCTING THE VEGETATED KEY, TRAFFIC CONTROL STONES, & SINGLE STONE BENDWAY WEIRS # 4 & 5.
“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”.

54 CONSTRUCTION DINGMANS CR-SITE 4 PIX BY DERRICK 9-19-2009
Looking stone being placed in the key for Bendway Weir #4. Live poles have already been placed in the key trench. “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 DINGMANS CR-SITE 4 PIX BY DERRICK

55 Key TCS SSBW Close-up of a Single Stone Bendway Weir (SSBW) & vegged key & pole plantings Thalweg

56 Looking DS @ many live pole plantings landward of the TCS.
“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 DINGMANS CR-SITE 4 PIX BY DERRICK

57 Looking across @ live poles & key stones in BW #5.
“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 DINGMANS CR-SITE 4 PIX BY DERRICK

58 Looking across @ Single Stone Bendway Weir #5.
“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 DINGMANS CR-SITE 4 PIX BY DERRICK

59 Weir construction complete, looking across @ Bendway Weir #5.
“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 DINGMANS CR-SITE 4 PIX BY DERRICK

60 CONSTRUCTION COMPLETE Photos by Dave Derrick SEPT. 24, 2009

61 CONSTRUCTION COMPLETE DINGMANS CR-SITE 4 DERRICK 9-24-2009
Construction complete, looking Bendway Weir #3, vegetated key, hillside plantings, TCS US & DS, & Random Boulder Field. CONSTRUCTION COMPLETE DINGMANS CR-SITE 4 DERRICK

62 CONSTRUCTION COMPLETE DINGMANS CR-SITE 4 DERRICK 9-24-2009
Construction complete, looking Bendway Weir #7, along with a vegetated key, hillside plantings, TCS, & Random Boulder Field. CONSTRUCTION COMPLETE DINGMANS CR-SITE 4 DERRICK

63 CONSTRUCTION COMPLETE DINGMANS CR-SITE 4 DERRICK 9-24-2009
Construction complete, looking DS. Left side hydraulically rough (and will become rougher as plantings grow), right side smooth. CONSTRUCTION COMPLETE DINGMANS CR-SITE 4 DERRICK

64 CONSTRUCTION COMPLETE DINGMANS CR-SITE 4 DERRICK 9-24-2009
Construction complete, looking toe & bank roughness due to TCS, Single Stone Bendway Weirs, Random Boulder Field, many pole plantings & rooted-stock plants provide roughness CONSTRUCTION COMPLETE DINGMANS CR-SITE 4 DERRICK

65 CONSTRUCTION COMPLETE DINGMANS CR-SITE 4 DERRICK 9-24-2009
Construction complete-Looking US. The secret to bank stabilization: smooth the opposite bank (point bar area), & roughen & toughen the eroding bank (toe & entire slide area) & bed using a Random Boulder Field. CONSTRUCTION COMPLETE DINGMANS CR-SITE 4 DERRICK

66 1 YEAR AFTER PROJECT COMPLETION Photos by Dave Derrick SEPT. 12, 2010
“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”.

67 1 YEAR LATER-DINGMANS CR.-SITE 4-PIX BY DERRICK 9-12-2010
1 YEAR LATER-Mid project Bendway Weirs, Traffic Control Stones, vegged floodplain bench, & Random Boulder Field. 1 YEAR LATER-DINGMANS CR.-SITE 4-PIX BY DERRICK

68 1 YEAR LATER-DINGMANS CR.-SITE 4-PIX BY DERRICK 9-12-2010
1 YEAR LATER-Mid-project Bendway Weirs, Traffic Control Stones, vegged floodplain bench, & Random Boulder Field. 1 YEAR LATER-DINGMANS CR.-SITE 4-PIX BY DERRICK

69 This PowerPoint presentation was developed & built by Dave Derrick
This PowerPoint presentation was developed & built by Dave Derrick. Any questions or comments, 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”.

70 Cleophus says “Geaux Saints”
“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”. Cleophus says “Geaux Saints”


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