17264 2019 UCC Cheboygan Lock Dive Inspection Report.pdf

WORLDWIDE LEADER IN COMMERCIAL DIVING

FOR OVER FORTY YEARS

AN EQUAL OPPORTUNITY EMPLOYER Page 1 of 17

UCC OFFICES – CONNECTICUT | MICHIGAN | TENNESSEE | WISCONSIN 800-USA-DIVE

5144 DOUGLAS AVENUE – RACINE WI | 53402 | T 877.717.DIVE | F 262-833-5900 UCCDIVE.COM

October 8, 2019

GEI Consultants 109 W. Baraga Avenue Marquette, MI 49855

Attn: Kevin Roell Senior Project Engineer, P.E., PMP Office: (906) 662-4750 Mobile: (906) 282-8959

Subject: Cheboygan Lock Inspection Report UCC Job No: 02-19-102.60, UCC Proposal: L-2522

Dear Mr. Roell, Underwater Construction Corporation is pleased to provide you with this report for the inspection performed on the Cheboygan lock. Attached are the inspection report and pictures illustrating the findings identified during the inspection.

In conclusion:

The lock walls are showing deterioration of the outside layer of shotcrete that was applied in 1977.

There were 9 areas of spalling noted with the deepest being 3 inches deep. When struck with a masonry hammer there was a duller sound. The lock floor had 2 areas of spalling up to 4 inches deep and some debris present. Gates, sluice gates, stop log guides, fill water openings and aprons appeared to be in good condition. The downstream apron toe was unformed with a void underneath.

This is believed to be over pour with the actual location of the toe being at the downstream endpoint of the concrete lock embankment walls. No void beyond that line was detectable. All seawalls were in good condition with no undermining or damaged knuckles, just minor gaps in corners and at interfaces with concrete walls. The rock basket wall was in overall good shape with no major damage to the baskets, however there was some slight undermining of the wall downstream of the power plant discharge and 1 area of deeper undermining where the baskets were beginning to sag.

Thank you, and if you should have any further questions please contact me or Griffin Eckert in the office at 877-717-3483 or through the listings provided below:

Jamison C Marchetti Griffin Eckert Cell: 586-980-7889 Cell: 269-985-3279 jmarchetti@uccdive.com geckert@uccdive.com

Sincerely, Jamison Marchetti Jamison Marchetti, UCC Assistant Foreman mailto:jmarchetti@uccdive.com mailto:geckert@uccdive.com

UCC Job # 02-19-102.60 Page 2 of 17

UNDERWATER CONSTRUCTION CORPORATION UCCDIVE.COM

GEI CONSULTANTS

CITY OF CHEBOYGAN

CHEBOYGAN LOCK

INSPECTION REPORT

Inspection Divers:

Jamison Marchetti, Bryan Tylk

Diving Supervisors:

Bryan Tylk

Boat Captain:

Ben Harvey

Inspected on:

September 25, 2019

Submitted By:

UNDERWATER CONSTRUCTION CORPORATION

5144 Douglas Ave Racine, WI 53402

Phone: (877) 717-DIVE Fax: (262) 833-5900

UCC Job # 02-19-102.60 Page 3 of 17

TABLE OF CONTENTS

SECTION PAGE

1.0 PURPOSE 4

2.0 SITE CONDITIONS 4

3.0 CREW AND EQUIPMENT 4

4.0 FINDINGS 5

4.1 LOCK 5

4.2 SEAWALLS 7

4.3 ROCK BASKET WALL 8

5.0 MAP WITH DIVE LAYOUT AND SITE PHOTOS 9

6.0 UNDERWATER IMAGES 12

7.0 DRAWING 17

7.1 CHEBOYGAN LOCK INSPECTION NOTES 17

UCC Job # 02-19-102.60 Page 4 of 17

PURPOSE

Perform underwater inspection of the following structures:

• Lock o Upstream embankment walls, stop log guides and apron o Lock gates, sluice gates, walls and floor o Downstream embankment walls, stop log guides and apron

• Downstream & upstream sheet pile seawalls o East (right side facing downstream) sheet pile wall – 125 feet long o West (left side facing downstream) sheet pile wall – 90 feet long o East (right side facing downstream) sheet pile wall – 340 feet long o West (left side facing downstream) sheet pile wall – 30 feet long

• Rock basket wall – 290 feet long Note: Wall lengths measured on Google Maps.

SITE CONDITIONS

Weather: 70°F partly sunny Plant Conditions: Power plant reduced discharge to 40% during rock basket wall inspection. Lock was lowered to downstream water level to equalize DP and eliminate flow during downstream and internal lock inspections.

Elevations: Upstream Cheboygan River: 590.6’ Downstream Cheboygan River: 574.1’

Visibility: 5 - 10 feet Current: Calm Water temp: 66°F Flow conditions: Low flow in areas diver was inspecting Access: Hydro II boat utilized for inspections. Cheboygan Dam boating access just upstream of lock was used to launch boat

CREW AND EQUIPMENT

3-man Dive Crew: 1 Diving Supervisor: Bryan Tylk 1 Boat Captain: Ben Harvey

2 Inspection Divers: Bryan Tylk Jamison Marchetti

Equipment: 1 DOT trucks: R1 1 trailer: Hydro II vessel with two (2) 250’ rigs and video capability

UCC Job # 02-19-102.60 Page 5 of 17

FINDINGS

4.1 LOCK

4.1.1 – LOCK WALLS

The Cheboygan lock was originally constructed in the 1920s. In 1977, the lock walls were resurfaced with shotcrete. The thickness of the shotcrete applied was unknown at the time of the inspection. No reinforcing steel rods, wire mesh nor fibers were visible during the inspection. Nine (9) areas of spalling ranging in depth from ½ inch to 3 inches were noted.

Examples of the spalling can be seen in Images 6.1 – 6.3. An area on the east wall displayed the beginning stages of spalling, with hairline cracking and delamination (Image 6.4). Throughout the lock, the diver encountered areas with linear marine growth (Image 6.5) which usually indicates a crack is below, however when the marine growth was cleaned off no cracking was visible. Perhaps micro cracking was present and undetectable to the diver’s naked eye due to reduced visibility underwater. The diver performed soundings on the lock walls using a masonry hammer and reported a dead sound throughout the lock, excluding the bottom 12 inches of the wall, which created a higher pitch sound when struck.

Overall the walls appeared to be in satisfactory condition, with no undermining nor minor tilting inward or outward of the lock walls detectable by the diver. Freeze/thaw damage with less than 1/8 inch material loss was noted throughout the lock. Refer to Drawing 7.1 for approximate locations and dimensions of noted deteriorations.

4.1.2 – STOP LOG GUIDES

Upstream (south end of the lock) stop log guides were formed concrete with a metal sleeve and appeared to be in good condition. The stop log guides were 100 percent covered with marine growth and sporadic zebra mussels. No spalling on the stop log guide edges was visible. The floor slot was formed concrete with no embedded steel noted and it was in good condition. It was approximately 75 percent filled with sand and debris, and would need to be cleaned prior to stop log installation to get a good seal at the stop log guide and floor interface. There was a formed opening in the concrete apron just downstream of the stop log guide floor slot and slightly off center to the west (with dimensions 10 inches long by 10 inches wide by 6 inches deep, based on existing drawings). The opening accepted a vertical member used as a back brace for the upstream stop logs. This opening was also full of sand and debris and would need to be cleaned prior to use.

Downstream (north end of lock) stop log guides were formed concrete with a metal sleeve and appeared to be in good condition. The stop log guides were 100 percent covered with marine growth and sporadic zebra mussel coverage. No spalling on the stop log guides was visible. On both sides of the lock, the stop log guides had concrete at the bottom. This concrete (12 inches thick on the east side and 3 inches thick on the west side) would need to be removed prior to stop log installation (Image 6.6). The floor slot was formed concrete with no embedded steel noted and was in good condition. This slot had less accumulated sand and debris in it, but should be cleaned prior to stop log installation.

UCC Job # 02-19-102.60 Page 6 of 17

Overall, the stop log guides appeared to be in satisfactory condition and suitable for stop log installation after a pre-installation cleaning of stop log guides and floor slots. Refer to Drawing 7.1 for additional information.

4.1.3 – FILL WATER OPENINGS

Two (2) fill water channels were present on the upstream side of the lock. The 2 intakes were located on both sides of the lock and in between the lock gate hinges and stop log guides. The intake openings had round steel bars evenly spaced across the opening, providing protection from large debris. All bars were present and securely in place. No large debris was found on either intake. The west intake had some long sea grass wrapped around the steel bars that was easily removed by the diver. The 2 discharge openings were located approximately 4 feet downstream of the upstream lock gates and were flush with the lock floor. The openings were formed concrete with chamfered edges.

All edges looked to be in good condition, with no spalling or scour. Refer to Drawing 7.1 for locations and additional information.

4.1.4 – LOCK FLOOR / APRONS

The upstream lock apron was in overall good condition with no cracking, spalling or undermining noted. The heel of the apron was covered by river bottom and no undermining was visible. The downstream apron was in overall good condition with no cracking or spalling noted. The diver initially noted 3 to 4 feet of undermining at the toe of the apron. After further analysis, this appeared to be concrete over pour. It is believed the true toe of the apron runs across the channel, flush to the downstream endpoint of the concrete lock walls. The end of the assumed concrete over pour extended 4 feet downstream of the concrete lock walls (Image 6.7). This 3 to 4 foot width matches up with the diver’s initial undermining depth of 3 to 4 feet. The diver was able to see the concrete disappear into the channel bottom where the true toe of the apron was believed to be. The diver performed soundings on both aprons using a masonry hammer. The diver reported a high pitch sound while striking the aprons, indicating good concrete condition. Refer to section 4.1.2 Stop Log Guides for details on the floor slot for stop logs.

Overall, the downstream and upstream aprons appeared to be in satisfactory condition, assuming that the void present at the toe of the downstream apron is over pour and not undermining. Refer to Drawing 7.1 for additional information.

The lock floor was fairly flat, with 2 areas of spalling noted, ranging from 3 to 4 inches deep. There was a fair amount of material on the bottom consisting of tree and construction debris and old cable anchor concrete buckets. There was a small diameter conduit pipe and concrete “bridge” that ran across the floor at the downstream endpoint of the lock gate wall slots (Image 6.8). The conduit pipe was approximately 6 inches above the lock floor and did not have any bracing holding it in place. It is unknown why the concrete “bridge” is there. The “bridge” varied in width and thickness. The diver could pass the masonry hammer underneath it in multiple locations.

Overall, the lock floor appeared to be in satisfactory condition with minimal spalling and no cracking or undermining. Refer to Drawing 7.1 for additional information.

UCC Job # 02-19-102.60 Page 7 of 17

4.1.4 – LOCK GATES & SLUICE GATES

The upstream lock gates each had 1 hydraulic operated sluice gate and a timber seal on the vertical edge where the gates meet when closed. Both sluice gates were in good condition with all hardware present. All of the guides were free of debris, allowing full range of motion. The upper left corner of the bottom west sluice gate guide was slightly bent, but this did not appear to affect the travel or sealing of the sluice gate. There were no rubber seals on the sluice gates nor within the guides. All lock and sluice gate steel and hardware had a white protective coating that was in good condition. A Cygnus Ultrasonic testing (UT) device was used to take thickness measurements on this gate. Thickness readings were: 0.355 inch, 0.340 inch, 0.370 inch and 0.370 inch.

The downstream lock gates each had 2 hydraulic operated sluice gates and a timber seal on the vertical edge where the gates meet when closed. All 4 sluice gates were in good condition with all hardware present. All guides were free of debris, allowing full range of motion. There were no rubber seals on the sluice gates nor within the guides. All lock and sluice gate steel and hardware had a white protective coating that was in good condition.

Horizontal timbers ran across the lock, just downstream of the lock gates, providing a bottom seal on the gates. These timbers were in good condition and secured in place. The upstream bottom seal timbers were not accessible during the inspection inside the lock due to the water level being equalized with the downstream river.

Overall, the lock gates appeared to be in satisfactory condition, with intact protective coating and fully functioning sluice gates. Refer to Drawing 7.1 for additional information.

4.2 SEAWALLS

Four (4) sections of seawall were inspected: the east and west upstream seawalls and the east and west downstream seawalls. No undermining or dislodged knuckles were noted on any of the sheet piles. All sheet pile walls had minor pitting and a layer of marine growth. The downstream seawalls had minimal zebra mussel growth. The upstream seawalls had 100 percent coverage of zebra mussels on the bottom half of the wall with minimal coverage near the surface. All ladder access points were in good condition. A Cygnus Ultrasonic testing (UT) device was used to take thickness measurements on the seawalls.

4.2.1 – WEST DOWNSTREAM SEAWALL (APPROX. 90 FEET LONG)

The diver noted a 1 inch gap between the sea wall and the power plant concrete wall.

Cygnus readings in this same location were 0.360 inch at 12 inches below the surface and

0.330 inch at 6 inches off the bottom. The engineer mentioned there was soil loss on shore, but the diver did not see any areas of soil deposit on the bottom.

4.2.2 – EAST DOWNSTREAM SEAWALL (APPROX. 125 FEET LONG)

The diver noted a small gap between the seawall and the concrete embankment wall. The diver was able to stick their fingertips inside and wrap them around the edge of the sheet pile. The engineer mentioned there was soil loss on shore, but the diver did not see any areas of soil deposit on bottom.

UCC Job # 02-19-102.60 Page 8 of 17

4.2.3 – WEST UPSTREAM SEAWALL (APPROX. 30 FEET LONG)

This portion of seawall is the oldest. There were horizontal seams where the sheet pile had been stacked on top of each other. All seams were in good condition and had no separation. Holes 2 inches in diameter were present where the inside fill aggregate could be seen. Thickness readings 24 inches below the surface were 0.380 inch, 0.355 inch and

0.375 inch and at the mudline were 0.350 inch, 0.330 inch and 0.340 inch.

4.2.4 – EAST UPSTREAM SEAWALL (APPROX. 340 FEET LONG)

This portion of seawall was in very good condition. The thickness reading 12 inches below the surface was 0.355 inch and at 24 inches off the bottom was 0.350 inch. The inside corner of seawall just upstream of the draw bridge landing had a gap ¼ inch to 3/8 inch wide by 1 inch deep from the mudline and up 1 foot.

Overall, the seawalls appeared to be in satisfactory condition with no undermining or dislodged knuckles. Refer to Drawing 7.1 for additional information.

4.3 ROCK BASKET WALL

The rock basket wall runs along the north shore for approximately 290 feet, across from the power plant discharge (Image 5.4). The diver noted a consistent, slight undermining of less than 1 foot for the portion of this row that was downstream and just upstream of the power plant. The furthest upstream portion of the wall did not have any undermining.

Approximately 30 feet upstream of the downstream endpoint there was a portion of the wall with 12 to 18 inches of undermining. Thirty (30) feet further upstream was a deeper section of undermining measuring 8 feet long by 9 inches wide by 4 feet deep. The diver was unable to see any sagging of the baskets underwater, however upon further investigation from topside, it was noted that some sagging and a gap between that row of baskets and the next outside row of baskets had developed. Directly across from the power plant discharge was a second row of fully submerged baskets. There was a separation between these 2 submerged rows of baskets at the far downstream end of the second submerged row (Image 6.10). This separation disappeared for the majority of this second row’s length. The diver did not report any consistent undermining of this second submerged row. There was a 12 inch diameter outfall pipe discharging in to the river through the rock basket wall, just downstream of the second row upstream endpoint. The diver reported a couple of areas where the chain-link fence basket was damaged, but there was not a large amount of aggregate spilling out of the wall.

Overall, the rock basket wall was in satisfactory condition. Turbulent water from the power plant discharge has begun to undermine the downstream portion of the rock wall. The deepest undermining has caused that portion of the wall to sag down and towards the center of the river.

UCC Job # 02-19-102.60 Page 9 of 17

MAP WITH DIVE LAYOUT AND SITE PHOTOS

N

FLO

W

FLO

LO

CK

EAST U

PSTREAM

SEAW

ALL

W

EST U

PSTREAM

SEAW

ALL

PO

W

ER

PLAN

T

EAST DO

W

N

STREAM

SEAW

ALL

W

EST DO

W

STREAM

SEAW

ALL

RO

CK BASKET

W

ALL

M

AP 5.1 – SITE LAYO

U T &

STRU

CTU

RE IDEN

TIFICATIO

PO

ER PLAN

T DISCHARG

E

DIVE 1 – Inspection of rock basket w all. Diver began at dow nstream end and traveled upstream

. Pow er plant discharge w as reduced to 40% during the inspection dive.

DIVE 2 – Inspection of dow nstream sea w alls and dow nstream apron of lock. Diver started w here the sea w all m eets the pow er plant. W ater level inside the lock w as equalized w ith the dow nstream river to elim inate w ater flow from leak by through lock gates and sluice gates.

DIVE 3 – Inspection of lock w alls, gates, sluice gates and floor. Diver started in N W corner follow ing perim eter of lock and finished w ith the floor inspection.

DIVE 4 – Inspection of upstream sea w alls and upstream apron of lock. Diver started at upstream endpoint of East upstream sea w all and traveled dow nstream to the upstream lock apron and finished traveling upstream along the W est upstream sea w all. W ater level inside the lock w as equalized w ith the upstream river to elim inate possible differential pressure at the lock gates, sluice gates and w ater fill intakes.

UCC Job # 02-19-102.60 Page 10 of 17

IMAGE 5.1 – LOOKING AT UPSTREAM

LOCK GATES FROM INSIDE LOCK

IMAGE 5.2 – LOOKING AT DOWNSTREAM

LOCK GATES FROM INSIDE LOCK

IMAGE 5.3 – LOOKING AT DOWNSTREAM

LOCK GATES FROM OUTSIDE LOCK

POSSIBLE

CONCRETE

OVER POUR

ASSUMED TOE OF

DOWNSTREAM APRON

UCC Job # 02-19-102.60 Page 11 of 17

IMAGE 5.4 – LOOKING UPSTREAM AT

ROCK BASKET WALL

UCC Job # 02-19-102.60 Page 12 of 17

IMAGE 6.1 – TYPICAL SPALLING ON LOCK WALL

UNDERWATER IMAGES

IMAGE 6.2 – 3” DEEP SPALLING ON LOCK WALL (KEYNOTE #8)

UCC Job # 02-19-102.60 Page 13 of 17

SPALL

DISCOLORATION

IMAGE 6.3 – 3” DEEP SPALLING ON LOCK WALL

(KEYNOTES #16 & #17)

IMAGE 6.4 – HAIRLINE CRACKING WITH DELAMINATION

(KEYNOTE #8)

UCC Job # 02-19-102.60 Page 14 of 17

IMAGE 6.6 – CONCRETE AT BOTTOM OF

DOWNSTREAM STOP LOG GUIDE

IMAGE 6.5 – LINEAR MARINE GROWTH

UCC Job # 02-19-102.60 Page 15 of 17

IMAGE 6.7 – DOWNSTREAM TOE OF APRON (KEYNOTE #1)

POSSIBLE OVER POUR

8” THICK IN CENTER &

THICKENS TO >36” AT SEA

WALLS

DOWNSTREAM APRON

VOID

18” – 24” WIDE

CONCRETE STRIP

SITTING ABOVE

LOCK FLOOR

LOCK FLOOR

LOCK

FLOOR

IMAGE 6.8 – CONCRETE SITTING ABOVE LOCK FLOOR

(SECTION A-A)

UCC Job # 02-19-102.60 Page 16 of 17

IMAGE 6.9 – TIMBER BOTTOM SEAL OF LOCK GATE

EAST DOWNSTREAM LOCK GATE

DOWNSTREAM APRON

IMAGE 6.10 – DOWNSTREAM ENDPOINT OF 2ND ROW OF SUBMERGED

ROCK BASKETS DIRECTLY ACROSS FROM POWER PLANT DISCHARGE

SECOND ROW OF

SUBMERGED

ROCK BASKETS.

DOWNSTREAM

END HAS

SEPARATED FROM

FIRST ROW AS

SHOWN

UCC Job # 02-19-102.60 Page17 of 17

DRAWING

4.3 ROCK BASKET WALL