Bridge_Inspection_Report_STR_5460-090P.pdf

STRUCTURE SUMMARY STRUCTURE NO. 5460-090P

MINGUS CREEK BRIDGE INSPECTION DATE: 5/23/17

BRIDGE IDENTIFICATION AND DESCRIPTION

MAIN SPAN MATERIAL: ....... CONCRETE NO. OF MAIN SPANS:

MAIN SPAN TYPE: ............... FRAME NO. OF APPR. SPANS:

# OF BEAMS, MAIN SPAN: .. 1 STRUCT. TOTAL LENGTH: .. 44.5 FT (13.6 M)

DECK TYPE: ......................... NOT APPLICABLE MAX. SPAN LENGTH: .......... 20.3 FT (6.2 M)

WEARING SURFACE: .......... NOT APPLICABLE DECK WIDTH: ...................... 35.5 FT (10.8 M)

ABUT. FOUNDATIONS: ........ UNKNOWN CURB TO CURB WIDTH: ..... 32.0 FT (9.8 M)

PIER FOUNDATION(S): ........ UNKNOWN YEAR BUILT:

ABUTMENT / PIER MAT'L: ... CONCRETE YEAR RECONSTRUCTED: .. N/A

PROJ./PLAN REF. NO: ......... 000000000000 / NONE SKEW ANGLE: ..................... 20 °

NPS ROAD CLASS: .............. 1 - PRINCIPAL PARK ROAD FRACTURE CRITICAL: ........ NO

STRUCTURE HISTORY: ...... 2010-ROADWAY REPAVED.

LOCATION

GREAT SMOKY MOUNTAINS NATIONAL PARK MILE POINT: ..................... 29.90 (KM PT 48.12)

STATE: ................................. NORTH CAROLINA LOCATION: 14.5 MILES SOUTH OF NEWFOUND GAP; IMMEDIATELY SOUTH OF MINGUS MILL FACILITY CARRIED: ............ NEWFOUND GAP ROAD

PARKING AREA.

FEATURE INTERSECTED: .. MINGUS CREEK

STRUCTURE EVALUATION SUMMARY

This concrete frame bridge is in fair condition overall, but exhibits some problems that require attention. These include scour along the substructure that has exposed up to 6" of the south abutment footing; moderate deterioration of the parapet and wingwall masonry mortar joints; and silt and debris accumulation at the upstream side of the north span, a condition that is restricting flow under the bridge.

Additional problems include a lack of reflective object markers at the bridge corners, and vegetation growth on and around the structure.

Corrective measures should be taken as outlined in this report to prevent the possible development of more serious or costly problems in the future.

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: 10/4/17

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

RECOMMENDATIONS AND ESTIMATED COSTS STRUCTURE NO. 5460-090P

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.

C226 PRIORITY OF IMPROVEMENT

ITEM

NO.

MAINTENANCE RECOMMENDATIONS

(GENERALLY NOT FLHP ELIGIBLE)

QTY. UNIT COST

UNIT

ESTIMATE

COST

PRELIM.

61.4 REMOVE SILT AND DEBRIS FROM UPSTREAM SIDE OF STRUCTURE, ESPECIALLY

NORTH SPAN.

1 LS

59.8, 60.6 REMOVE VEGETATION GROWTH FROM WINGWALLS AND EXTERIOR SIDES OF

FRAME.

1 LS

222.7 INSTALL REFLECTIVE OBJECT MARKERS AT BRIDGE CORNERS. 4 EA

PRELIM. MAINTENANCE TOTAL :

ITEM

NO.

REHABILITATION/RECONSTRUCTION

(TYPICALLY NEEDED WITHIN 5 YEARS)

QTY. UNIT

UNIT

COST ESTIMATES

PRELIM. COST

REHAB. RECONSTR.

58.6, 60.6 CLEAN AND REPOINT PARAPET AND WINGWALL MASONRY MORTAR

JOINTS.

1 LS

60.9,17, 61.2

PLACE SCOUR COUNTERMEASURES ALONG SOUTH ABUTMENT

AND NORTH CHANNEL.

1 LS

CONTRACT COSTS FOR MOBILIZATION, TRAFFIC CONTROL, AND

DESIGN CONSTRUCTION ENGINEERING (APPROXIMATELY 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. 5460-090P

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

CONDITION RATING CODE EQUIVALENTS FOR SUB-ELEMENTS

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 sec ion 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 CODES FOR ITEMS 58 - 62, 222, 223

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.

N

58. DECK ITEM REFERENCE AND REMARKS

OTHER

ALIGNMENT

DEFLECTION AND/OR VIBRATION

FASCIA(E)

DIAPHRAGMS AND BRACING

TRUSSES

FLOOR BEAMS AND STRINGERS

ARCH(ES) OR SLAB(S)

GIRDERS OR BEAMS

BEARING DEVICES

59. SUPERSTRUCTURE

OTHER

DEFLECTION AND/OR VIBRATION

UTILITIES

DRAINS AND DRAINAGE

PARAPETS AND/OR RAILINGS

CURBS, SIDEWALKS, AND MEDIAN

RIDEABILITY

WEARING SURFACE

EXPANSION JOINTS

DECK SLAB

ABUTMENTS

60. SUBSTRUCTURE

1.

10.

2.

3.

4.

5.

6.

7.

8.

9.

10.

9.

8.

7.

6.

5.

4.

3.

2.

1.

PAINT

11.

N

N N G N N N N F G

N G

G G N F G N

N

N

N

N

58.6 MODERATE DETERIORATION OF PARAPET MASONRY MORTAR

JOINTS. MINOR VEGETATION GROWTH ALONG PARAPETS.

59.3,8 MINOR LONGITUDINAL CRACKING OF SLAB UNDERSIDE. MINOR

MAP CRACKING OF SLAB UNDERSIDE, PRIMARILY TOWARD WEST

SIDE. MINOR DELAMINATION OF SLAB UNDERSIDE IN SOUTH SPAN

NEAR SOUTH ABUTMENT. MODERATE EFFLORESCENCE ON SLAB

UNDERSIDE FROM RING STONES IN SOUTH SPAN, WEST SIDE.

MODERATE TO HEAVY EFFLORESCENCE FROM RING STONE

MASONRY MORTAR JOINTS. HEAVY MOSS AND VEGETATION

GROWTH ON EXTERIOR SIDES OF FRAME.

60.1,13 MINOR CRACKING OF ABUTMENT BREASTWALL AND PIER WALL

MASONRY MORTAR JOINTS WITH MINOR EFFLORESCENCE.

MODERATE CRACKING OF NORTH ABUTMENT BREASTWALL AT

BASE OF WEST SIDE RING STONES. 1/4 "W CRACK AT EAST END OF

PIER AT PREVIOUSLY REPAIRED AREA ON NORTH SIDE AND SOUTH

SIDE.

60.5,9,16,17 MODERATE SCOUR ALONG SUBSTRUCTURE HAS EXPOSED TOP OF

SOUTH ABUTMENT FOOTING (UP TO 6" H) TOWARD DOWNSTREAM

SIDE; MODERATE SCALING OF EXPOSED FOOTING.

PIER APPEARS TO BE FOUNDED ON BEDROCK.

MINOR EROSION ALONG WINGWALLS; MODERATE AT SOUTHWEST

WINGWALL.

60.6 MINOR TO MODERATE DETERIORATION OF WINGWALL MASONRY

MORTAR JOINTS; SEVERE AT SOUTHEAST WINGWALL. HEAVY

MOSS AND VEGETATION GROWTH ON WINGWALLS.

60.7 WEST WEEP HOLE AT NORTH ABUTMENT COVERED BY SILT.

BREASTWALLS OR COLUMNS 1. G

PILE BENTS 2. N

CAPS AND/OR BEARING SEATS 3. N

BACKWALLS AND/OR BULKHEADS 4. N

FOUNDATIONS 5. F

WINGWALLS 6. F

WEEP HOLES 7. F

EXPANSION JOINTS 8. N

EROSION AND/OR SCOUR 9. F

SETTLEMENT OR DEFLECTION 10. G

SLOPE PROTECTION 11. N

OTHER 12. N

PIER(S)

F13. WALLS AND/OR COLUMNS

N14. PILE BENTS

N15. CAPS AND/OR BEARING SEATS

F16. FOUNDATIONS

F17. EROSION AND/OR SCOUR

G18. SETTLEMENT OR DEFLECTION

N19. OTHER

INSPECTION DATE: 5/23/17

STRUCTURE NO. 5460-090P FIELD INSPECTION REPORT

MINGUS CREEK BRIDGE

ITEM REFERENCE AND REMARKS

AVERAGE CLEAR OPENING 8.

NORMAL VELOCITY 7.

ADEQUACY OF OPENING 6.

OTHER 5.

WATERWAY OBSTRUCTIONS 4.

CHANNEL PROTECTION 3.

EROSION AND/OR SCOUR 2.

1. ALIGNMENT

61. CHANNEL 6

F F N F N

HIGH

SUFF

7 FT.

9. STREAM BED COMPOSITION :

SAND, ROCK, SILT, STONES

222. APPROACHES 8

OTHER 9.

ALIGNMENT 8.

SIGNS 7.

SETTLEMENT 6.

EROSION 5.

SURFACING 4.

APPROACH GUARDRAIL 3.

RELIEF JOINTS 2.

1. APPROACH SLABS N

N N G G G N F N

223. RETAINING WALL N

OTHER 6.

SETTLEMENT OR DEFLECTION 5.

EROSION AND/OR SCOUR 4.

FOUNDATION 3.

WEEP HOLES 2.

1. WALL

36. TRAFFIC AND SAFETY FEATURES

APPROACH GUARDRAIL ENDS D.

APPROACH GUARDRAILS C.

TRANSITIONS B.

BRIDGE RAILINGSA. 0

N N N

61.1,2 CHANNEL ALIGNMENT CAUSING SCOUR AND EROSION AT

SOUTHWEST WINGWALL. MODERATE EROSION WITH

UNDERMINING ALONG NORTH DOWNSTREAM CHANNEL BANK.

61.4 SILT AND DEBRIS ACCUMULATION AT UPSTREAM SIDE OF

STRUCTURE PARTIALLY BLOCKING NORTH SPAN. LARGE TREE

DOWN ALONG NORTHWEST WINGWALL EXTENDING OVER 1/2 OF

NORTH SPAN. MINOR ACCUMULATION OF DEBRIS AT UPSTREAM

SIDE OF PIER.

222.7 MISSING REFLECTIVE OBJECT MARKERS AT ALL BRIDGE CORNERS.

222.8 ROADWAY ON CURVED ALIGNMENT.

36.A PARAPET HEIGHT VARIES BETWEEN 1'-1" TO 2'-5" AND DOES NOT

MEET CURRENT SAFETY REQUIREMENT OF 2'-3" FOR TRAFFIC

BARRIERS.

TRAFFIC SAFETY RATING CODES

N

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

Meets currently acceptable standards.

Not applicable or a safety feature is not required.

STRUCTURE LOAD RATING STRUCTURE NO. 5460-090P

TRUCK TYPE

INVENTORY RATING (NORMAL TRAFFIC) OPERATING RATING (MAXIMUM LOAD)

TONS METRIC TONS TONS METRIC TONS

H 15 14 25 23

HS 27 24 45 41

TYPE 3 21 19 35 32

TYPE 3S2 34 31 56 51

TYPE 3-3 41 37 69 63

DESIGN LOADING: UNKNOWN

X CAPACITY MEETS OR EXCEEDS DESIGN LOAD

CAPACITY IS LESS THAN DESIGN LOAD

ORIGINAL LOAD RATING CALCULATION APPLICABLE

ORIGINAL LOAD RATING CALCULATION REVISED

DATE OF LOAD RATING CALCULATION:

LOAD RATING CONTROLLED BY:

REMARKS: RATING IS BASED ON ENGINEERING JUDGEMENT IN ACCORDANCE WITH AASHTO MANUAL FOR BRIDGE

EVALUATION (MBE).

STRUCTURE INVENTORY AND APPRAISAL STRUCTURE NO. 5460-090P

STRUCTURE IDENTIFICATION

(201) PARK: GREAT SMOKY MOUNTAINS NATIONAL PARK (1) STATE: ....................................... 374 - NORTH CAROLINA (NC)

(202) STRUCTURE NAME: .......... MINGUS CREEK BRIDGE (2) STATE HWY. AGENCY DIST:

(203) STRUCTURE KIND: ............ 1 - BRIDGE (3) COUNTY CODE: ........................ 173 - SWAIN

(204) STRUCTURE NUMBER: ..... 5460-090P (4) CITY/PLACE CODE:

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

(206) ROUTE CODE NUMBER: ... 10 (6) FEATURES INTERSECTED:....... MINGUS CREEK

(207) ROAD SECTION NO: .......... 090P (7) FACILITY CARRIED: .................. NEWFOUND GAP ROAD

(208) NPS ROAD CLASS: ............ 1 - PRINCIPAL PARK ROAD (8) STATE STRUCTURE NO: .......... 5460090P0000000

(209) WITHIN NPS BNDRY?: ....... YES (9) LOCATION: ................................ 14.5 MILES SOUTH OF NEWF

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

(211) PROJECT NO(S): ................ 000000000000 (11) MILE POINT: ............................. 29.90 (KM PT 48.12)

(212) DRAWING NUMBERS: ....... NONE (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: .. 3 - POSSIBLY 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:

1 - CONCRETE

07 - FRAME

20.3 FT (6.2 M)

44.5 FT (13.6 M)

0 - UNKNOWN

0 - UNKNOWN

0 - UNKNOWN

0 - UNKNOWN

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: ................. 0 - NONE

C) TYPE PROTECTION: .............. 0 - NONE

(218) IS SALT USED?: ..................... NO

LOAD RATING AND POSTING

(31) DESIGN LOAD: ................. 0 - UNKNOWN (41) LOAD RESTRICTION: ......... A - OPEN, NO RESTRICTION

(66) INVENTORY RATING: ...... 27.0 TONS (24.5 METRIC TONS) (70) BRIDGE POSTING: .............. 5 - NO POSTING REQUIRED

(64) OPERATING RATING: ...... 45.1 TONS (40.9 METRIC TONS)

INSPECTION DATES

(90) INSPECTION DATE: 5/17 (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. 5460-090P

GEOMETRY, TRAFFIC, AND NAVIGATIONAL DATA

(16) LATITUDE: ............................. 35°31'12.50" (51) CURB TO CURB WIDTH: ........... 32.0 FT (9.8 M)

(17) LONGITUDE: ......................... 83°18'28.20" (52) DECK WIDTH: ............................ 35.5 FT (10.8 M)

(19) DETOUR LENGTH: ............... 90 MI (145 KM) (32) APPR. ROADWAY WIDTH: ........ 32.0 FT (9.8 M)

(28A) LANES ON STRUCT: .......... 02 (213) APPR. PAVEMENT WIDTH: ..... 22.0 FT (6.7 M)

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

(42A) SERVICE ON: ..................... 1 - HIGHWAY RIGHT SHOULDER: ................ 6.0 FT (1.8 M)

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

(29) AVG. DAILY TRAFFIC: .......... 6300 (34) SKEW ANGLE: ............................ 20 °

(30) YEAR OF ADT: ...................... 2009 (35) DECK FLARE?: ........................... NO

(114) FUTURE ADT: ..................... 6930 (47) TOTAL HORIZ. CLEARANCE: .... 32.0 FT (9.8 M)

(115) YEAR OF FUTURE ADT: ..... 2029 (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: ......... 3 - PARAPET ONLY

(111) ABUT. OR PIER PROT: ....... MATERIAL: .............................. 9 - OTHER

DESIGN TYPE: ........................ 1 - CONTINUOUS RAIL

LATERAL UNDERCLEARANCE:

(55) RIGHT: ....................... 0.0 FT (0.0 M) (215) BRIDGE RAIL HEIGHT: ............ 1.08 FT (0.33 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:

(60) SUBSTRUCTURE:

(61) CHANNEL:

(62) CULVERT: ........................... N

(222) APPROACHES:

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

(36) TRAFFIC SAFETY FEAT: ... 0NNN

(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

4 - Stable; action required to pro

2 - REHAB/RECONSTRUCTION

C - MODERATE

ADDITIONAL INFORMATION

(230) STRUCTURE HISTORY:

2010-ROADWAY REPAVED.

(231) ADDITIONAL CONSIDERATIONS:

(330) ADDITIONAL CONFIG. INFO.:

APPENDIX STRUCTURE NO. 5460-090P

PHOTOGRAPHS STRUCTURE NO. 5460-090P

PHOTO #1 - LOOKING SOUTH TOWARD NEWFOUND GAP

FLOW

PHOTO #2 - GENERAL TOPSIDE VIEW LOOKING SOUTH

PHOTO #3 - WEST (UPSTREAM) SIDE

PHOTO #4 - GENERAL UNDERSIDE VIEW OF NORTH BARREL LOOKING

DOWNSTREAM;TYPICAL LONGITUDINAL CRACKING OF SLAB

UNDERSIDE

PHOTO #5 - TYPICAL MOSS GROWTH ON

SURFACE OF PARAPET WALLS

DETERIORATING MASONRY JOINTS; WEST

SIDE SHOWN

PHOTO #6 - TYPICAL EROSION AROUND END

OF PARAPET WALLS; SOUTHEAST END

SHOWN

PHOTO #7 - GENERAL UNDERSIDE VIEW OF SOUTH BARREL LOOKING

DOWNSTREAM

PHOTO #8 - TYPICAL EFFLORESCENCE ON NORTH WALL MASONRY

MORTAR JOINTS, NOTE BUILD-UP OF EFFLORESCENCE ON EAST SIDE

RING STONES

PHOTO #9 - TYPICAL BUILD-UP OF EFFLORESCENCE ALONG RING

STONES OF NORTH BARREL, UPSTREAM SIDE; NOTE ACCUMULATION

OF VEGETATION AND SEDIMENT BUILD-UP ON UPSTREAM SIDE

PHOTO #10 - GENERAL VIEW OF SOUTH WALL OF SOUTH BARREL;

NOTE BUILD-UP OF EFFLORESCENCE ALONG MORTAR JOINTS AND

INSIDE FACE OF RING STONES; ALSO NOTE VEGETATIVE GROWN ON

PHOTO #11 - TYPICAL EFFLORESCENCE BUILD-UP ON INTERMEDIATE

WALL ALONG MORTAR JOINTS; NORTH FACE SHOWN; NOTE COBBLE

ACCUMULATION ALONG BASE OF WALL AND BARREL FLOOR

PHOTO #12 - TYPICAL VEGETATIVE GROWTH ALONG WEST HEADWALL

PHOTO #13 - GENERAL VIEW OF CHANNEL LOOKING UPSTREAM FROM

DECK

PHOTO #14 - GENERAL VIEW OF CHANNEL LOOKING DOWNSTREAM

FROM DECK