5140-010P1275_Redacted.pdf

STRUCTURE NO. 5140 010P

OTTER CREEK CULVERT #4 INSPECTION DATE: 11/2/16

STRUCTURE SUMMARY

CULVERT IDENTIFICATION AND DESCRIPTION

MAIN SPAN MATERIAL: ........ CONCRETE CONTINUOUS NO. OF BARRELS:

FOUNDATION: ....................... SPREAD FTG ON BEARING MAT'L

BARREL LENGTH: ............... 121 FT (37 M)

STRUCT. TOTAL LENGTH: ... 104.8 FT (31.9 M) SKEW ANGLE: ..................... 66 °

MAX. SPAN LENGTH: ............ 32.3 FT (9.8 M) 1954

YEAR BUILT:

PROJ./PLAN REF. NO: .......... 1G8 / 3003

YEAR RECONSTRUCTED: .. N/A

NPS ROAD CLASS: ............... 1 - PRINCIPAL PARK ROAD

STRUCTURE HISTORY: ....... 1983-JOINT REPAIR.

LOCATION

BLUE RIDGE PARKWAY MILE POINT: ..................... 59.59 (KM PT 95.90)

STATE: .................................. VIRGINIA LOCATION: 1.9 MILES TO VA ROUTE 130

FACILITY CARRIED: ............. BLUE RIDGE PARKWAY

FEATURE INTERSECTED: ... OTTER CREEK

STRUCTURE EVALUATION SUMMARY

This three barrel concrete box culvert is in fair condition overall. The main problems at this time include accumulation of debris and stone in the center and south barrels which is blocking the flow, and a heavy accumulation of drift at the upstream end of the north barrel and north interior wall. An area of scour exists at the upstream end of the north end wall.

Additional problems include widespread masonry mortar joint deterioration; settlement cracks at the ends of the barrel walls and southwest wingwall; exposed rebar on the slab underside; and heavy vegetation growth along the headwalls and wingwalls.

Corrective action should be taken as outlined in this report to prevent the possible development of more serious or costly problems in the future. In addition, consideration should be given to installing a guardrail system to help improve motorist safety.

INSPECTION TEAM: R. SILVESTRY, L. ELLIS

CONDITION ASSESSMENT:

REINALDO SILVESTRY, FIELD TEAM LEADER 703-404-6251

REPORT REVIEW:

MARCUS MILLER, P.E., BRIDGE INSPECTION ENGINEER 703-404-6252

REPORT APPROVAL: DATE: 3/31/17

JORGOMAI CEESAY, PH.D., P.E., BIP SUPERVISORY ENGINEER 703-404-6244

RECOMMENDATIONS AND ESTIMATED COSTS STRUCTURE NO. 5140 010P

226 PRIORITY OF IMPROVEMENT C

A (Critical) - Structure is closed, in imminent danger of collapse, or presents a critical safety hazard.

B (Major) - Structure exhibits severe deterioration, presents a safety hazard, or is designated a high priority due to age and/or condition.

C (Moderate) - Structure is deficient, functionally obsolete, or requires substantial repairs to prevent a serious deficiency or unsafe condition.

D (Minor) - Structure is generally in good condition. Preventative maintenance may be required.

E (Special) - Structure is under construction or reconstruction.

ITEM

NO.

MAINTENANCE RECOMMENDATIONS

(GENERALLY NOT FLHP ELIGIBLE)

QTY. UNIT COST

UNIT

ESTIMATE

COST

PRELIM.

62.3,4 REMOVE VEGETATION FROM WINGWALLS AND ABOVE HEADWALLS. 1 LS

PRELIM. MAINTENANCE TOTAL :

ITEM

NO.

REHABILITATION/RECONSTRUCTION

(TYPICALLY NEEDED WITHIN 5 YEARS)

QTY. UNIT

UNIT

COST ESTIMATES

PRELIM. COST

REHAB. RECONSTR.

62.9, 222.3 INSTALL GUARDRAIL SYSTEM OVER STRUCTURE AND AT

APPROACHES.

1 LS

61.1,2,4, 62.5,6

REMOVE ACCUMULATION OF DRIFT FROM UPSTREAM SIDE OF

CULVERT. REMOVE ACCUMULATION OF STONE AND SILT FROM

CENTER AND SOUTH BARRELS, THEN REDIRECT CHANNEL AWAY

1 LS

62.1,3,4 CLEAN AND REPOINT MASONRY MORTAR JOINTS AS NECESSARY. 1 LS

62.6 PLACE ENGINEERED RIPRAP AT UPSTREAM END OF NORTH

BARREL.

1 LS

62.1,4 CLEAN AND SEAL SETTLEMENT CRACKS IN BARREL WALLS AND

SOUTHWEST WINGWALL.

1 LS

62.1 CLEAN EXPOSED REBAR ON SLAB UNDERSIDE AND COAT WITH

APPROVED PROTECTIVE SEALANT.

1 LS

CONTRACT COSTS FOR MOBILIZATION, TRAFFIC CONTROL, AND

DESIGN CONSTRUCTION ENGINEERING (70% TOTAL REHAB COST)

PLUS PARK LOCATION FACTOR.

1 LS

PRELIM. REHABILITATION/RECONSTRUCTION TOTAL :

PRELIMINARY ESTIMATE TOTAL* :

(*Includes typical contract costs for mobilization, traffic control, and design/construction engineering; but does not include detour bridges, work beyond the bridge limits, or work not listed above. Estimates are approximate and are for preliminary planning purposes only; they should not be used as a complete or final engineers estimate.)

REMARKS: Cost estimates assume that recommended actions will be combined with similar work being performed on other structures.

FIELD INSPECTION REPORT STRUCTURE NO. 5140 010P

CONDITION RATING CODES FOR ITEMS 58 - 62, 222, 223

N

NOT APPLICABLE

EXCELLENT CONDITION

VERY GOOD CONDITION - no problems noted.

GOOD CONDITION - some minor problems.

SATISFACTORY CONDITION - structural elements show some minor deterioration.

FAIR CONDITION - all primary structural elements are sound but may have minor section loss, cracking, spalling, or scour.

POOR CONDITION - advanced section loss, deterioration, spalling, or scour.

SERIOUS CONDITION - loss of section, deterioration, spalling, or scour have seriously affected primary structural components. Local failures are possible.

Fatigue cracks in steel or shear cracks in concrete may be present.

CRITICAL CONDITION - advanced deterioration of primary structural elements. Fatigue cracks in steel or shear cracks in concrete may be present or scour may have removed substructure support. Unless closely monitored it may be necessary to close the structure until corrective action can be taken.

“IMMINENT” FAILURE CONDITION - major deterioration or section loss present in critical structural components or obvious vertical or horizontal movement affecting structure stability. Structure is closed to traffic but corrective action may return structure to light service.

FAILED CONDITION - out of service; beyond corrective action.

CONDITION RATING CODE EQUIVALENTS FOR SUB-ELEMENTS

G = GOOD (CODES 7 - 9) F = FAIR (CODES 5 - 6) P = POOR (CODES 0 - 4)

61. CHANNEL 5

F ALIGNMENT1.

F EROSION AND/OR SCOUR2.

N 3. CHANNEL PROTECTION

P4. WATERWAY OBSTRUCTIONS

N 5. OTHER

6. ADEQUACY OF OPENING SUFF

NORMAL VELOCITY MED 7.

8 FT.AVG. CLEAR OPENING 8.

ITEM REFERENCE AND REMARKS

61.1, 62.5 NO FLOW IN CENTER AND SOUTH BARRELS DUE TO MODERATE

STONE AND SILT ACCUMULATION, RESULTING FROM NORTHWARD

STREAM MIGRATION.

61.2 MODERATE EROSION OF UPSTREAM CHANNEL BANKS; TREE

UNDERMINING ALONG SOUTH UPSTREAM CHANNEL BANK. MINOR

EROSION OF NORTH DOWNSTREAM CHANNEL BANK.

61.4, 62.6 HEAVY DRIFT ACCUMULATION ALONG UPSTREAM END OF NORTH

INTERIOR WALL AND BARREL. AREA OF SCOUR (8' L X 2' W X 3' D)

ALONG UPSTREAM END OF NORTH ENDWALL. FALLEN TREE IN

UPSTREAM CHANNEL ~50' FROM STRUCTURE.

9. STREAM BED COMPOSITION :

SAND, SILT, ROCK

62. CUL VERT 6

PARAPETS AND/OR RAILINGS 9.

ADEQUACY OF COVER 8.

SETTLEMENT AND/OR DEFLECTION 7.

EROSION AND/OR SCOUR 6.

5. DEBRIS AND/OR SILT

4. WINGWALLS

3. HEADWALLS

2. FOOTINGS

1. BARREL(S)

ROADWAY SURFACE10.

11. RIDEABILITY

12. OTHER

F

G

F

F

F

F

F

G

N

G

G

N

222. APPROACHES 8

OTHER9.

8. ALIGNMENT

SIGNS 7.

6. SETTLEMENT

EROSION5.

SURFACING4.

APPROACH GUARDRAIL3.

RELIEF JOINTS 2.

APPROACH SLABS1. N

N

N

G

G

G

N

G

N

223. RETAINING WALL N

6. OTHER

5. SETTLEMENT OR DEFLECTION

4. EROSION AND/OR SCOUR

3. FOUNDATION

2. WEEP HOLES

1. WALL

36. TRAFFIC AND SAFETY FEATURES

C. APPROACH GUARDRAILS

B. TRANSITIONS

A. BRIDGE RAILINGS

D. APPROACH GUARDRAIL ENDS

TRAFFIC SAFETY RATING CODES

0 - Does not meet standards or a safety feature is required and none is provided.

1 - Meets currently acceptable standards.

N - Not applicable or a safety feature is not required. 3 OF 18

FIELD INSPECTION REPORT STRUCTURE NO. 5140 010P

ADDITIONAL ITEM REFERENCE AND REMARKS

62.1,7 WIDESPREAD MINOR TRANSVERSE CRACKING WITH EFFLORESCENCE ON SLAB UNDERSIDE IN ALL BARRELS;

LEAKAGE AND RUST STAINING IN SOME AREAS. WIDESPREAD MODERATE VERTICAL AND HORIZONTAL

CRACKING WITH EFFLORESCENCE ON EXTERIOR FACES OF SLAB.

MODERATE SPALL (24"L X 12"W X 3"D) WITH EXPOSED REBAR ON SLAB UNDERSIDE AT WEST END OF NORTH

BARREL. THREE MINOR SPALLS WITH EXPOSED AND RUSTED REBAR AT WEST END OF CENTER BARREL.

AREAS OF MINOR HONEYCOMBING OF SLAB UNDERSIDE IN CENTER BARREL.

ISOLATED AREAS OF MINOR EFFLORESCENCE ON INTERIOR BARREL WALLS. WIDESPREAD MINOR TO

MODERATE CRACKING AND DETERIORATION OF NORTH AND SOUTH BARREL WALL MASONRY MORTAR JOINTS

WITH EFFLORESCENCE AND MOISTURE SEEPAGE; UP TO FULL DEPTH DETERIORATION OF MORTAR JOINTS AT

WATERLINE IN NORTH BARREL.

1/4" WIDE DIAGONAL CRACK IN MORTAR JOINTS AT WEST END OF SOUTH EXTERIOR WALL EXTENDING

VERTICALLY, 1/16" WIDE, THROUGH TWO STONES AT BASE; CONCENTRATED CRACKING ON SLAB UNDERSIDE IN

VICINITY. 1/4" WIDE DIAGONAL CRACK IN MORTAR JOINTS AT EAST END OF NORTH EXTERIOR WALL EXTENDING

VERTICALLY, 1/16" WIDE, THROUGH TWO STONES AT BASE. MINOR DIAGONAL CRACK AT EAST END OF SOUTH

EXTERIOR WALL.

CRACKING AND SEPARATION BETWEEN TOP OF NORTH INTERIOR WALL AND MORTAR LEVELING COURSE AT

EAST END. 1/2" WIDE HORIZONTAL CRACK AT WEST END OF SOUTH INTERIOR WALL.

62.3 HEAVY VEGETATION GROWTH ABOVE HEADWALLS. MODERATE CRACKING OF HEADWALL MASONRY MORTAR

JOINTS.

62.4,7 MODERATE TO HEAVY VEGETATION GROWTH ON WINGWALLS. MINOR DETERIORATION OF WINGWALL

MASONRY MORTAR JOINTS WITH EFFLORESCENCE. SEVERAL 1/4" WIDE SETTLEMENT CRACKS IN SOUTHWEST

WINGWALL.

62.10 MINOR LONGITUDINAL AND TRANSVERSE CRACKING OF ASPHALT PAVEMENT.

222.5 SEVERAL POCKETS OF MINOR SLOPE EROSION BEHIND HEADWALLS.

222.7 NO HEADWALL MARKERS PRESENT.

36.A,B,C,D NO GUARDRAIL SYSTEM PRESENT.

STRUCTURE NO. 5140 010P

INSPECTION DATE: 11/2/16

TRUCK TYPE

TONS

INVENTORY RATING (NORMAL TRAFFIC)

METRIC TONS METRIC TONSTONS

OPERATING RATING (MAXIMUM LOAD)

H

HS

TYPE 3

TYPE 3S2

TYPE 3-3

DESIGN LOADING:

DATE OF LOAD RATING CALCULATION:

LOAD RATING CONTROLLED BY:

REMARKS:

CAPACITY MEETS OR EXCEEDS DESIGN LOAD

CAPACITY IS LESS THAN DESIGN LOAD

ORIGINAL LOAD RATING CALCULATION APPLICABLE

ORIGINAL LOAD RATING CALCULATION REVISED

END SPAN POSITIVE MOMENT

7/16

X

X

STRUCTURE LOAD RATING

OTTER CREEK CULVERT #4

UNKNOWN

STRUCTURE INVENTORY AND APPRAISAL STRUCTURE NO. 5140 010P

STRUCTURE IDENTIFICATION

(201) PARK: BLUE RIDGE PARKWAY (1) STATE: ....................................... 513 - VIRGINIA (VA)

(202) STRUCTURE NAME: .......... OTTER CREEK CULVERT #4 (2) STATE HWY. AGENCY DIST:

(203) STRUCTURE KIND: ............2 - CULVERT (3) COUNTY CODE: ........................ 009 - AMHERST

(4) CITY/PLACE CODE:

(204) STRUCTURE NUMBER: ..... 5140-010P

(205) NPS REGION: .................... 4 - SOUTHEAST (5) INVENTORY ROUTE:

(206) ROUTE CODE NUMBER: ... 1 (6) FEATURES INTERSECTED:....... OTTER CREEK

(207) ROAD SECTION NO: ..........010P (7) FACILITY CARRIED: .................. BLUE RIDGE PARKWAY

(208) NPS ROAD CLASS: ............ 1 - PRINCIPAL PARK ROAD (8) STATE STRUCTURE NO: .......... 5140010P0000000

(209) WITHIN NPS BNDRY?: ....... YES (9) LOCATION: ................................ 1.9 MILES TO VA ROUTE 130

(210) OPERATING UNIT: ............. JAMES R. (10) INV. RTE. - MIN. VERT. CLR: .. 99.99 FT (99.99 M)

(211) PROJECT NO(S): ................ 1G8 (11) MILE POINT: ............................. 59.59 (KM PT 95.90)

(212) DRAWING NUMBERS: ....... 3003 (27) YEAR BUILT:

(21) MAINTAINED BY: ................. 66 - NATIONAL PARK SERVICE (106) YEAR RECONSTRUCTED: .... N/A

(22) OWNER: ............................... 66 - NATIONAL PARK SERVICE (20) TOLL: ........................................ 3 - FREE ROAD

(37) HISTORICAL DESIGNATION: .. 5 - NOT ELIGIBLE

STRUCTURE DESCRIPTION, FOUNDATION, AND DECK TYPE

(43A) MAIN STR. MATERIAL: ..

(43B) MAIN STR. TYPE:

(45) NO. OF MAIN SPANS:

(48) MAX. SPAN LENGTH:

(49) STRUCTURE LENGTH:

(216A) ABUTMENT #1 FDN:

(216B) ABUTMENT #2 FDN:

(217A) PREDOM. PIER FDN.: ..

(217B) SECOND. PIER FDN: ...

(107) DECK TYPE:

2 - CONCRETE CONTINUOUS

19 - CULVERT

32.3 FT (9.8 M)

104.8 FT (31.9 M)

2 - SPREAD FTG ON BEARING MAT'L

2 - SPREAD FTG ON BEARING MAT'L

2 - SPREAD FTG ON BEARING MAT'L

2 - SPREAD FTG ON BEARING MAT'L

N - NOT APPLICABLE

(44A) APPR. STR. MATERIAL: ........ 0 - OTHER

(44B) APPR. STR. TYPE: ................ 00 - OTHER

(46) NO. OF APPROACH SPANS: .. 0

(108) WEAR SURFACE/PROTECT SYSTEM:

A) TYPE WEARING SURFACE: .. N - NOT APPLICABLE

B) TYPE MEMBRANE: ................. N - NOT APPLICABLE

C) TYPE PROTECTION:

0 - NONE

NO(218) IS SALT USED?:

LOAD RATING AND POSTING

(31) DESIGN LOAD:

0 - UNKNOWN (41) LOAD RESTRICTION:

R - POSTED (OTHER)

(66) INVENTORY RATING: ...... 99.9 TONS (99.9 METRIC TONS) (70) BRIDGE POSTING: .............. 5 - NO POSTING REQUIRED

(64) OPERATING RATING: ...... 99.9 TONS (99.9 METRIC TONS)

INSPECTION DATES

(90) INSPECTION DATE: 11/16 (91) FREQ. OF INSP: 24 MONTHS (92 / 93) CRITICAL FEATURE INSPECTION (CFI):

(219) ADD. STUDIES NEEDED: N - 0 - NONE (A) FRACTURE CRITICAL: ... NO

INSP. EVERY: MONTHS - LAST INSP. : (220) SPECIAL STUDY TYPE: 0 - NONE

(B) UNDERWATER: .............. NO

(221) SPECIAL STUDY DATE:

INSP. EVERY: MONTHS - LAST INSP. :

(C) SPECIAL INSPECTION: .. NO

INSP. EVERY: MONTHS - LAST INSP. :

STRUCTURE INVENTORY AND APPRAISAL STRUCTURE NO. 5140 010P

GEOMETRY, TRAFFIC, AND NAVIGATIONAL DATA

(16) LATITUDE: ............................. 37°35'20.60" (51) CURB TO CURB WIDTH: ........... 0.0 FT (0.0 M)

(17) LONGITUDE: ......................... 79°19'37.80" (52) DECK WIDTH: ............................ 0.0 FT (0.0 M)

(19) DETOUR LENGTH: ............... 25 MI (40 KM) (32) APPR. ROADWAY WIDTH: ........ 28.5 FT (8.7 M)

(28A) LANES ON STRUCT: .......... 02 (213) APPR. PAVEMENT WIDTH: ..... 20.5 FT (6.2 M)

(28B) LANES UNDER STRUCT: ... 00 LEFT SHOULDER: .................. 4.0 FT (1.2 M)

(42A) SERVICE ON: ..................... 1 - HIGHWAY RIGHT SHOULDER: ................ 4.0 FT (1.2 M)

(42B) SERVICE UNDER: .............. 5 - WATERWAY (33) BRIDGE MEDIAN: ....................... 0 - NO MEDIAN

(29) AVG. DAILY TRAFFIC: .......... 474 (34) SKEW ANGLE: ............................ 66 °

(30) YEAR OF ADT: ...................... 2012 (35) DECK FLARE?: ........................... NO

(114) FUTURE ADT: ..................... 521 (47) TOTAL HORIZ. CLEARANCE: .... 28.5 FT (8.7 M)

(115) YEAR OF FUTURE ADT: ..... 2032 (50) SIDEWALKS:

(101) PARALLEL STRUCTURE: ... N - NONE LEFT : ...................................... 0.0 FT (0.0 M)

(38) NAVIGATION CONTROL?: ... 0 RIGHT : ................................... 0.0 FT (0.0 M)

(39) VERTICAL CLEARANCE: ...... 0.0 FT (0.0 M) (214) BRIDGE RAIL TYPE:

(40) HORIZ. CLEARANCE: ........... 0.0 FT (0.0 M) RAIL CONFIGURATION: ......... 0 - N/A

(111) ABUT. OR PIER PROT: ....... MATERIAL: .............................. 0 - N/A

DESIGN TYPE: ........................ 0 - N/A

LATERAL UNDERCLEARANCE:

(55) RIGHT: ....................... 0.0 FT (0.0 M) (215) BRIDGE RAIL HEIGHT: ............ 0.00 FT (0.00 M)

(56) LEFT: ......................... 0.0 FT (0.0 M) (53) MIN. VRT. CLEAR. OVER DECK: 99.99 FT (99.99 M)

(54) MIN. VRT. UNDERCLEARANCE: 0.00 FT (0.00 M)

CONDITION AND APPRAISAL DATA, PROPOSED IMPROVEMENTS, AND COST

(58) DECK: .................................N

(59) SUPERSTRUCTURE: .........N

(60) SUBSTRUCTURE: ..............N

(61) CHANNEL:

(62) CULVERT:

(222) APPROACHES:

(223) RETAINING WALL: ........... N

(36) TRAFFIC SAFETY FEAT: ... 0000

(75A) TYPE OF WORK:

(75B) WORK DONE BY:

(76) IMPROVEMENT LENGTH: ..

(67) STRUCTURAL EVALUATION:

(68) DECK GEOMETRY:

(69) UNDERCLEARANCES:

(71) WATERWAY ADEQUACY:

(72) APPROACH ALIGNMENT:

(113) SCOUR CRITICAL:

(225) PURPOSE OF IMPROVEMENT:

(226) PRIORITY OF IMPROVEMENT:

(227) MAINTENANCE COST:

(228) REHAB./RECONSTR. COST: ...

(229) CONSTRUCTION COST:

N

8 - Stable; scour above top of fo

2 - REHAB/RECONSTRUCTION

C - MODERATE

ADDITIONAL INFORMATION

(230) STRUCTURE HISTORY:

1983-JOINT REPAIR.

(231) ADDITIONAL CONSIDERATIONS:

(330) ADDITIONAL CONFIG. INFO.:

CULVERT LENGTH = 118'.

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APPENDIX STRUCTURE NO. 5140 010P

PHOTOGRAPHS STRUCTURE NO. 5140 010P

FLOW

PHOTO #1 - LOOKING SOUTHBOUND TOWARD ROANOKE

PHOTO #2 - EAST (UPSTREAM) SIDE

PHOTO #3 - GENERAL TOP SIDE VIEW LOOKING SOUTH

PHOTO #4 - GENERAL UNDERSIDE VIEW LOOKING WEST, BARREL #3

STRUCTURE NO. 5140 010P

PHOTO #5 - TYPICAL LONGITUDINAL

CRACKING WITH EFFLORESCENCE ON SLAB

UNDERSIDE; BARREL #1 NEAR WEST END

SHOWN

PHOTO #6 - FULL LENGTH LONGITUDINAL

CRACKING WITH EFFLORESCENCE NEAR

CENTER OF NORTH BARREL; NOTE ALSO

EVIDENCE OF ACTIVE WATER LEAKAGE

PHOTOGRAPHS

PHOTO #7 - SPALL WITH EXPOSED REBAR ON SLAB UNDERSIDE AT

WEST END OF NORTH BARREL; NOTE ALSO CRACKING OF

HORIZONTAL MORTAR JOINTS

PHOTO #8 - SPALLING WITH EXPOSED REBAR ON SLAB UNDERSIDE AT

WEST END OF BARREL #2

STRUCTURE NO. 5140 010PPHOTOGRAPHS

PHOTO #9 - TYPICAL CRACKING WITH EFFLORESCENCE ON EXTERIOR

FACES OF SLAB; EAST FACE OF BARREL #2 SHOWN

PHOTO #10 - EFFLORESCENCE BUILD-UP THROUGHOUT LENTH OF

SOUTH WALL OF BARREL #3

PHOTO #11 - TYPICAL CRACKING AND SEPARATION ALONG TOP OF

INTERIOR WALLS AT MORTAR JOINT LEVEL COURSE; NORTH FACE OF

WALL BETWEEN BARRELS #2 AND #3 SHOWN

PHOTO #12 - DIAGONAL CRACK IN MORTAR JOINTS AT WEST END OF

SOUTH EXTERIOR WALL EXTENDING VERTICALLY THROUGH TWO

STONES AT BASE; BARREL #3 SHOWN

PHOTO #13 - ACCUMULATION OF DEBRIS, SILT

AND STONES IN CENTER BARREL

PHOTO #14 - TYPICAL DETERIORATION OF

WINGWALL MASONRY MORTAR JOINTS;

NORTHEAST WINGWALL SHOWN

PHOTO #15 - SETTLEMENT CRACKS IN

SOUTHWEST WINGWALL (PHOTO FROM

10/18/10 INSPECTION)

PHOTO #16 - FALLEN TREES AT UPSTREAM

END OF BARREL #2

PHOTO #17 - DRIFT ACCUMULATION ON UPSTREAM END OF BARREL #3

PHOTO #18 - AREA OF SCOUR ALONG UPSTREAM END OF BARREL #3

ENDWALL

PHOTO #19 - LOOKING UPSTREAM; NOTE FALLEN TREE AND DEBRIS

ALONG CHANNEL

PHOTO #20 - LOOKING DOWNSTREAM THROUGH BARREL #3