1305M326Q0067_SOW_A1_2024_Manchester_Pier_Inspection_Report.pdf

Manchester Pier Inspection Manchester, WA

Submitted To:

Client:

GoldenWolf, LLC 9100 Conroy Windermere Road, Suite 200 Windermere, FL 34786

Owner:

National Oceanic and Atmospheric Administration 7600 Sand Point Way NE Seattle, WA 98115

Pier Inspection & Report

GOLDW24001

November 27, 2024

Katherine Kelly, ADCI, PE Senior Engineer / Underwater Inspector Professional Engineer: Pennsylvania – No. PE081817 i

November 27, 2024

GOLDW24001

GoldenWolf, LLC Attn: Chris Flowers, Director of Asset Management 9100 Conroy Windermere Road Suite 200 Windermere, FL 34786

RE: FACILITY CONDITION ASSESSMENT AND STRUCTURAL ASSESSMENT

FOR THE NOAA – MULTIPLE SITES, FY24

TASK 4 – MANCHESTER, WA PIER INSPECTION

Dear Mr. Flowers:

We are pleased to submit our preliminary engineering report for the Manchester Pier Assessment in general accordance with the Scope of Services presented in our proposal dated June 26, 2024, and your subsequent authorization to proceed.

As discussed in the proposal, the Load Rating Analysis will be a separate task. A revised report and/or appendix will be provided upon the completion of the analysis, with updates based on the findings to be incorporated where appropriate.

We trust that the information presented in this report is what you require at this time, and we thank you for the opportunity to assist you with this project.

If you have any questions, or if you need any further assistance with this project, please contact this office at your earliest convenience.

Respectfully, PENNONI ASSOCIATES INC.

Katherine Kelly, ADCI, PE Senior Engineer / Underwater Inspector

2024 Manchester Pier Inspection Report i

TABLE OF CONTENTS

Executive Summary

Introduction General Information Site History , Descript ion and Or ientat ion

Inspection Methodology Inspect ion Act iv it ies Inspect ion Approach Inspect ion Metr ics

Inspection Findings Deck/Curb Str ingers Pi le caps Pi les Cross Bracing Other Accessor ies and Attachments

Conclusions and Recommendations

Appendix A: 2024 Drawings

Appendix B: 2024 Condit ion Tables

Appendix C: 2024 Timber Core Sampling

Executive Summary The Manchester Pier is located in Manchester State Park and exposed to the marine environment of Clam Bay. The main portion of the Pier is ±810-feet long and is generally comprised of timber pile bents (piles with a timber pile cap), timber stringers, and timber decking. The pier is owned by the EPA, but National Marine Fisheries Services (NMFS) has an agreement to use and maintain this facility. The Pier was built circa 1930’s and major repairs (piles caps, stringers, deck and curbs) were performed in 1989. No as-built or design drawings were available for review. The last known inspection was performed in 2008.

Pennoni completed a Routine Inspection covering both topside and underwater elements to assess the general condition, assign condition ratings, and provide recommendations for future maintenance. The purpose of this inspection was to document the current defects, analyze the Pier for its current use, and make prioritized repair recommendations based on the current usage, as well as to support the load rating task Pennoni completed a Routine Inspection covering both topside and underwater elements. The inspection was led by a Professional Engineer/Diver with extensive experience in both underwater and topside inspection. The inspection was conducted using a combination of commercial SCUBA and wading techniques. The inspection included the following underwater inspection “levels of effort”:

• 100% Level I – visual / tactile on all elements.

• 10% Level II – cleaning for representative samples on 10% of all underwater elements.

• 5% Level III – non-destructive or partially destructive testing as necessary (timber cores).

The inspection was performed based on guidance from the American Society of Civil Engineering (ASCE) Manuals and Reports on Engineering Practice No. 130 – Waterfront Facilities Inspection and Assessment (ASCE MOP 130).

The Pier is in overall SERIOUS condition, with several areas showing signs of advanced deterioration. The individual components vary from Satisfactory to Critical condition, and are governed by the deteriorated piles and unsupported pile cap spans. The timber elements exhibit widespread deterioration, typically checks, splits, rot and other miscellaneous defects. The surface defects create a potential entry point for water infiltration and rot, which may further impact the long-term structural capacity of the elements. Other medium, low, and maintenance priorities have been included for long-term planning.

The Pier rating is governed by the condition of the piles and pile caps. The timber piles themselves exhibit widespread advanced deterioration and local failures due to advanced rot that has essentially compromised the entire section of the pile. The pile conditions also impact the functionality of the pile caps. Although the pile caps themselves are generally in satisfactory condition, the missing/deteriorated piles below the cap impact the load path. For example, in locations where the end pile is missing/severely deteriorated, the pile cap is now essentially cantilevered. Similarly, in locations where a middle pile is missing/severely deteriorated, the pile caps are now supporting a much longer span.

These conditions result in increased stresses and reduced structural effectiveness, as the configuration is longer than originally designed.

The Manchester Pier has essentially outlived its originally designed useful lifespan. The Pier is approximately 90-years old, is constructed with timber elements with unknown treatment types, and is exposed to an aggressive marine environment. Structures of this age and material require ongoing maintenance and repairs to maintain their use. It is likely that the timber piles will continue to deteriorate over time, requiring an ongoing repair and replacement program.

A summary table of the elements, ratings, repairs and priorities is included on the following page The recommendations in the table were developed to prioritize the worst cases and allow for future budgeting. An updated report will be provided upon the completion of the load rating task. Finalized recommendations and priorities will be updated based on load rating analysis.

max.edwards Highlight max.edwards Highlight max.edwards Highlight max.edwards Highlight max.edwards Highlight

Component Rating Brief Summary of Repairs Priority

Deck 5 - Satisfactory Reset hardware. Medium

Clean and re-treat decking. Maintenance

Curb 4 - Fair

Replace curb base at Bent 83. Medium

Shim non-bearing locations. Medium

Replace missing hardware. Medium

Clean and re-treat curb. Maintenance

Stringers 5 - Satisfactory Clean and re-treat pile stringers. Maintenance

Shim non-bearing locations. Low

Pile Caps 5 - Satisfactory

Clean and re-treat pile caps. Maintenance

Periodically remove sand/debris. Maintenance

No additional loads (equipment, trucks, water tanks, etc.) are placed on the outshore 10-feet of the pier.

High

Piles 2 - Serious

Repair/replace piles with over 75% deterioration. High

Install new piles at Bent 83. High

Repair/replace piles with over 35% deterioration. Medium

Shim all non-bearing locations. Medium

Replace all wire rope wraps. Low

Cross Bracing 1 - Critical Replace all cross bracing. High

Other - Inspection

N/A Inspect the Pier annually until high priority repairs are complete.

N/A

Condition Assessment Rating and Repair Summary Table

Introduction General Information The Manchester Pier is located in Manchester State Park in Manchester, WA on the southern bank of the Rich Passage approximately 10 miles west of Seattle. The pier is exposed to the marine environment of Clam Bay. The pier is owned by the EPA, but National Marine Fisheries Services (NMFS) has an agreement to use and maintain this facility. See Figures 1 and 2 below. The following sections include a detailed facility description and orientation that was used.

Figure 1 – Vicinity Map

Figure 2 – Location Map

Site History, Description and Orientation The Manchester Pier was built circa 1930. According to on-site personnel, the Pier supported one end of submarine net that spanned across the channel to a sister pier during World Ward II to protect the nearby Naval Shipyard. The submarine net was deployed with a large crane located at the outshore end of the Pier. No as-built or repair drawings were available for review. However, according to on-site personnel, substantial work was performed on the pier circa 1989, including: miscellaneous pile repairs and full replacement of the pile caps, stringers and decking. No substantial repairs have been completed since.

Currently, the Pier is located at a shared facility with numerous buildings and other structures for various federal agencies. The Pier is used by personnel to: access the floating docks, access the fish nets/facility at the end of the pier, transport fish from the fish nets in tow-behind water tanks (typically once or twice per year), and to stage the replacement of the intake pumps adjacent to the fish nets (typically 3 to 4 year cycle). See the Load Rating Analysis in the Appendices (pending) for additional discussion of loads and usage.

The main portion of the Pier is ±810-feet long and is generally comprised of timber pile bents (piles with a timber pile cap), timber stringers, and timber decking. The Pier spans from the parking area/former helicopter pad eastward into the Bay. For the purposes of this inspection, the Pier is oriented as inshore/west and outshore/east, with north and south faces.

The inshore ±655-feet of the pier is 25-feet wide, the outshore ±120-feet is 45-feet wide, and there is a flared transition between the two sections. The 2008 inspection noted discrepancies in the original drawings (not available during this work), which indicated 83 pile bents, though only 82 were observed in both the 2008 and 2024 inspections. To maintain consistency with the previous report, Bent 1 and Span 1 were excluded from the numbering system. Note, there appears to be a reflective crack in the asphalt approximately 10-feet from the inshore end of the Pier. It is possible that Bent 1 was buried during previous construction.

Photo 1 - General top of deck near Bent 2 looking east. Photo 2 - General top of deck near Bent 65 looking east.

The Pier substructure consists of 82 pile bents spaced at ±10-feet on center. Bents are sequentially numbered from west to east, inshore to offshore, beginning at Bent 2 and extending to Bent 83. There are a mix of plumb/bearing piles and battered piles. The piles vary in size but are typically 12 to 14-inch diameter. Piles are labeled alphabetically from north to south. Pile configurations vary throughout the pier with the standard configurations listed below. Note that the actual configurations vary, with supplemental and sister piles installed at some locations. See also the drawings in Appendix A for the pile and bent layout.

• Bents 2 – 16 include: 4 piles (D, E, F, and G).

• Bents 17 – 68 include: 6 piles (D-plumb, D-battered, E, F, G-battered, and G-plumb).

• Bent 69 includes: 9 piles (C-plumb, C-battered, D-plumb, D-battered, E, F-battered, F-plumb, G-battered, and G-plumb).

• Bent 70 includes: 10 piles (B-plumb, B-battered, C-plumb, C-battered, D, E, F-battered, F-plumb, G-battered, and

G-plumb).

• Bents 71 – 83 include: 11 piles (A-plumb, A-battered, B-plumb, B-battered, C, D, E, F-battered, F-plumb, G-battered, and G-plumb).

Figure 3 - Pile Orientation.

Photo 3 - Typical 6-pile bent layout.

Photo 4 – Typical 11-pile bent layout (fisheye view).

The timber piles caps also varied in configuration throughout the pier, including: 12” x 16” timber pile caps, and 12” x 14” timber pile caps with 4” x 12” timber top plates. It appears that two of the 12” x 14” caps were installed incorrectly and that an additional top plate was installed to adjust for the height difference without needing to modify the stringers.

From Bents 70 to 83, there is lateral and longitudinal bracing in the tidal zone spanning along and between bents respectively.

Photo 5 - General view of Pile Cap 79 looking southeast. Photo 6 - General view of Pile Cap 26 looking northwest.

The Pier superstructure is comprised of timber stringers, timber deck planks, and timber curbs. The timber planks are comprised of 12” wide x 4” high timbers that span across the stringers and are secured with varying hardware. The stringers bear on the timber caps and span between adjacent bents. The stringers are typically 4” x 12” timbers, spaced at 1’-9” on center average, and vary from 14 to 29 stringers per span. Stringers in Span 2 through 5 are 4” x 14” timbers while Spans 6 through 83 the stringers are 4” x 12” timbers. Stringers are numbered north to south. Most of the stringers are simply supported (they span from one bent to the adjacent bent), but some cantilever over the caps or are continuous across multiple bents. There is a 10” wide x 12” high timber curb (above the deck) with intermittent blocking along the full perimeter, and a 12” wide x 12” high curb base (below the deck), full length along the north and south faces.

The Pier also has impact protection around the perimeter. From Bents 17 to 83, there are 12-inch fender piles located along the outside perimeter of the Pier at the north and south ends of each bent. The fender piles are secured with U-bolts. There are multi-pile dolphin clusters at the outshore (northeast and southeast) corners. The fender piles and dolphins are non-structural and were generally omitted from the scope of the inspection.

Photo 7 - Northeast dolphin cluster looking west.

The Pier is shared with other on-site agencies. There is a floating dock along the south face approximately 200-ft from the inshore end (between Bents 29 and 39) that is utilized by the National Park Services for boat access. The NPS dock is connected to the Bents 29 and 30 pile caps with two (2) 20’-2” long MC10x28.5 channels, that cantilever 10.6-feet towards the south. There is a combination of fixed and floating docks and a series of fish nets along the south face at the outshore end (between Bents 65 and 83) that are utilized by the NMFS. This dock is independent of the pier structure and self-supported. The permanent structure is supported by multiple concrete piles. The platform/walkways are not connected to the main timber pier. These are independent structures and not included as part of the scope. They were reviewed only for their potential impact on the load rating assessment.

Photo 8 - Overview of docks at outshore end. Photo 9 - Overview of floating dock at Bent 29.

Additional appurtenances and loads observed on the Pier include:

• Life rings at the south side of Bent 24, south side at Bent 48 and north side at Bent 73.

• Mooring cleats at breaks in the curb at Bents 33, 34, 38, and 54 on the south side and bents 33, 38, and 54 on the north side of the pier.

• A 12-inch diameter timber light pole at Bent 80.

• A 4’-4” wide x 4’-4” long x 14” thick concrete pad at Bent 74.

• Multiple electrical boxes at the outshore end along the south face.

• Miscellaneous construction debris (pipe, pallets, etc.).

• A tow-behind 500-gallon water container near the outshore end.

• A chain link fence at Bent 34.

• Monitoring equipment (antennas) mounted at Bents 79 and 82.

Inspection Methodology Inspection Approach The purpose of this inspection was to document the current defects, analyze the Pier for its current use, and make prioritized repair recommendations based on the current usage. The inspection approach was performed based on guidance from the American Society of Civil Engineering (ASCE) Manuals and Reports on Engineering Practice No. 130

– Waterfront Facilities Inspection and Assessment (ASCE MOP 130). Pennoni completed a Routine Inspection covering both topside and underwater elements to assess the general condition, assign condition ratings, and provide recommendations for future maintenance.

The inspection included the following summary of underwater inspection levels:

• 100% Level I – visual / tactile on all elements.

• 10% Level II – cleaning for representative samples on 10% of all underwater elements.

• 5% Level III – non-destructive or partially destructive testing as necessary.

ASCE defines the above mentioned levels of underwater inspection effort levels as follows:

Level I: A close visual examination above and underwater or a tactile examination using large sweeping motions of the hands where visibility is limited underwater. Although the Level I effort is often referred to as a “swim by" inspection, it must be detailed enough to detect obvious major damage or deterioration due to overstress or other severe deterioration. It should confirm the continuity of the full length of all members and system components and detect undermining or exposure of normally buried elements. A Level I effort may also include limited probing of the substructure and adjacent channel bottom.

Level II: A detailed inspection above and underwater that requires wrappings, coatings, corrosion, and/ or marine growth to be removed from portions of the structure. Underwater marine growth removal is sampling of components. For piles, a 12-inch high band should be cleaned at designated locations, generally near the low waterline, at the mudline, and midway between the low waterline and the mudline. On a rectangular pile, the marine growth removal should include at least three sides; on an octagonal pile, at least six sides; and on a round pile, at least three-fourths of the perimeter. On large-diameter piles, 3-feet or greater, 1-foot x 1-foot areas should be cleaned at four locations approximately equally spaced around the perimeter, at each elevation. On large solid faced elements, such as retaining structures, 1-foot x 1-foot areas should be cleaned at these three elevations. The Level II effort should also focus on typical areas of weakness such as connections, attachment points, and welds. The Level II effort is intended to detect and identify damaged and deteriorated areas that may be hidden by surface biofouling, coating, or corrosion, or that which may not be readily accessible for a Level I inspection effort. The thoroughness of marine growth removal should be governed by what is necessary to discern the condition of the underlying material. Removal of all biofouling staining is generally not required.

Means and methods for the removal of growth are not typically defined in a scope of work. However, it may be appropriate for owners to specify particular methods based on environmental and site conditions or on concern for maintaining the integrity of coating materials. Methods may include hand scrapers or mechanical systems ranging from high-pressure water blasters to barnacle busters and pressurized air bubble devices based on the principles of cavitation.

Level III: A detailed inspection above and underwater typically involving nondestructive or partially destructive testing conducted to detect hidden or interior damage, or to evaluate material homogeneity. Typical inspection and testing techniques include the use of ultrasonic, coring and boring, physical material sampling, and in situ hardness testing. Level III testing is generally limited to key structural areas, areas that are suspect or areas that may be representative of the structure or system.

Inspection Metrics ASCE MOP 130 also provides a structured framework for evaluating the condition of waterfront structures, focusing on both above-water and underwater components. The rating system used for this report is based on the ASCE MOP 130 Condition Assessment Rating definitions, as seen in Table 1. These ratings assess structural elements based on the severity of deterioration and their impact on load-bearing capacity. This goal of this common rating framework is to ensure consistency in evaluating the structural integrity of the various pier elements between cycles and across inspectors/companies. Observations from all inspection efforts are utilized to assign these ratings, guide load rating analysis, prioritize maintenance, and recommend repairs.

Rating Description

6 – Good No visible damage or only minor damage noted. Structural elements may show very minor deterioration, but no overstressing observed. No repairs are required.

5 – Satisfactory Limited minor to moderate defects or deterioration observed but no overstressing observed. No repairs are required.

4 – Fair

All primary structural elements are sound but minor to moderate defects or deterioration observed.

Localized areas of moderate to advanced deterioration may be present but not significantly reduce the load-bearing capacity of the structure. Repairs are recommended, but the priority of the recommended repairs is low.

3 – Poor Advanced deterioration or overstressing observed on widespread portions of the structure but does not significantly reduce the load-bearing capacity of the structure. Repairs may need to be carried out with moderate urgency.

2 – Serious

Advanced deterioration, overstressing, or breakage may have significantly affected the load-bearing capacity of primary structural components. Local failures are possible, and loading restrictions may be necessary. Repairs may need to be carried out on a high priority basis with urgency.

1 – Critical

Very advanced deterioration, overstressing, or breakage has resulted in localized failure(s) of primary structural components. More widespread failures are possible or likely to occur, and load restrictions should be implemented as necessary. Repairs may need to be carried out on a very high-priority basis with strong urgency.

Table 1 - Condition Assessment Rating Definitions (Based on ASCE MOP 130)

Inspection Activities The inspection was conducted on between October 15 – 22, 2024 by a 3-person dive team as follows: Katherine Kelly, PE, ADCI – Team Leader / Dive Supervisor / Inspection Diver; Matthew Houtmann, PE, ADCI – Team Member / Inspection Diver; Spencer Hoagland, EIT, ADCI – Team Member / Inspection Diver. The inspection was led by a Professional Engineer/Diver with extensive experience in both underwater and topside inspection, including the FHWA Underwater Bridge Inspection Course (NHI-130091).

All diving was conducted in accordance with current Association of Diving Contractors International (ADCI) consensus standards. A site specific safety plan was developed and approved in advance of the work. The safety plan was based on USACE EM-385-1-1 format with staffing levels as per ADCI requirements. The inspection was conducted using a combination of commercial SCUBA and wading techniques. Dive operations were staged from shore, floating docks, or a 12-feet long heavy-duty inflatable boat (zodiac style) as determined for best access based on location and tasks. The note takers utilized the previous report drawings and numbered signs attached to the bents to track Bent and Pile numbers throughout the inspection.

Water levels varied greatly based on tidal swings, which can vary up to 12-feet high. Daily tides during this inspection typically included: a low-low tide, high-low tide, and low-high tide, and high-high tide, see Figure 4 below. Accordingly, the diving was staged around the tides when possible. Low tides were primarily utilized to document conditions within the tidal zone, which were then accessible for the topside personnel via boat. High tides were primarily utilized to document the superstructure, pile caps, bearing conditions and other defects at the upper elevations. Continuously submerged and continuously dry elements were primarily inspected during tidal shifts.

Figure 4 - NOAA Tide Chart at the Time of Inspection

On-site conditions varied daily. Weather was typically partly cloudy, with scattered rain and sun. Air temperatures were seasonal – 50 to 60°F during the day, with water temperatures around 50°F near the surface. The current varied based on the tides but was typically less than 1 knot with steady sea states. Underwater visibility was good, 5-feet to 15-feet typical. See Table 2 below for additional details.

Date Weather Air Temp.

(°F) Water

Temp. (F) Visibility

(ft) Currents (knots)

10/15/24 Partially Cloudy 61 54.5 5+ <1

10/16/24 Partially Cloudy 62 54.1 5+ <1

10/17/24 Partially Cloudy/Scattered Rain

54 54.5 5+ <1

10/18/24 Partially Cloudy/Scattered Rain

53 54.1 5+ <1

10/21/24 Partially Cloudy 62 52.9 5+ <1

10/22/24 Sunny 56 53.4 5+ <1

Table 2 - Inspection conditions (water depths, visibility, tidal range, currents, weather, etc.)

Additional on-site safety hazards included: an electrified rail around portions of the fish nets/floating docks, intake pipes near the outshore end and boat traffic from the NPS vessels. The rail was turned off and on as needed during dive operations. The intake pipes were offset from the areas of inspection. The NPS boat generally goes underway or returns at the beginning and end of the day, and dive ops near the dock were staged between this schedule.

Inspection Findings This section documents the inspection findings and condition ratings based on ASCE MOP 130 guidance for the combined above water and underwater routine inspection of the Manchester Pier. The section is organized into subsections by element type, including a brief description of the elements, defect descriptions and an overall assessment of each element. The sections are organized starting from the top of the structure (deck and curbs) to the bottom (piles), with a supplement section at the end for miscellaneous other elements.

Deck The timber deck is in overall 5 – Satisfactory condition, due to the random minor to moderate defects throughout. The deck planks typically exhibit minor checks and splits, with no significant defects noted. There are random locations with splits near the corners of a board, resulting in minor section loss (see Photo 10). There are random locations with splitting at hardware.

The top face of the timber decking exhibits minor to moderate deterioration throughout. This surface wear is more pronounced between Bents 68 and 83, which can be used as a turnaround for vehicles. It is likely that the wear has also removed much of the deck’s preservative treatment, leaving the wood vulnerable to further deterioration. In many locations, the surface deterioration has exposed the head of the fasteners, typically 1/4-inch high. There are random locations where the hardware has come loose and protrudes 1 to 2-inches above the decking. There are random locations of missing hardware.

Photo 10 - Timber decking with moderate surface wear, and exposed hardware at outshore end.

Decking near Bent 71 shown. Note also the board with splitting at the corner.

Photo 11 - Top of deck looking east.

Photo 12 - Typical cracking of timber decking.

Photo 13 - Typical fasteners not fully seated.

Curb The timber curb (or “bull rail”) is in overall 4 – Fair condition due to the widespread minor to moderate defects with areas of localized major deterioration. The curbs (above the deck planks) typically exhibit minor checks and splits throughout. These defects allow water and vegetation to penetrate beyond the preservative protection and into the member, resulting in localized rot. There is widespread minor to moderate vegetation growth (grasses, moss, etc.)

throughout, typically found at splits or along the top surface (see Photo 14). There are random localized areas of moderate deterioration, such as wide splits at hardware penetrations with heavy vegetation growth. There is random missing connection hardware at isolated locations. The curb support chocks are typically in-place and connected.

The curb base (below the deck planks) exhibits similar minor checks and splits throughout with isolated moderate to major defects. A wide split, 50” long x 6” high x 2” deep is present at a thru-bolt on the north side of Bent 83 (see Photo 17). There are also 10 locations on the pier where the shims between the curb base and timber cap have failed due to various issues, including partial, rotted, split, or missing shims. This has resulted in bearing loss for those sections of the curb base, as follows:

• North curb base: Bent 12 (See Photo 20), Bent 22, Bent 56.

• South curb base: Bent 9, Bent 10 (See Photo 18), Bent 11(See Photo 19), Bent 12, Bent 78, Bent 81(See Photo

21), Bent 82.

Photo 14 - Typical cracking and vegetation in south curb in Span 46.

Photo 15 - Missing bolt in 8th curb from west end.

Photo 16 - Typical cracking and splitting in curb at connection hardware.

Photo 17 - North curb base split, 50" L x 6" H x 2", at Bent 83.

Photo 18 - South curb base is 75% non-bearing due to misaligned shim at Bent 10.

Photo 19 - South curb base shim 100% rotted at Bent 11.

Photo 20 - North curb base is 100% non-bearing due to failed shim at Bent 12.

Photo 21 - South curb base shim is split and failed at Bent 81.

Stringers The timber stringers are in overall 5 – Satisfactory condition, due to the random minor defects throughout (See Photo 22). The stringers exhibit random minor checks, splits and surface staining, with no areas of major deterioration noted.

As mentioned in the Structural Description and Orientation section, the stringers vary slightly in size and orientation.

The stringers in Spans 2 through 5 and 26 are 4” wide x 14” high timbers, while those in Spans 6 through 25 and 27 to 82 are 4” wide x 12” high timbers. To accommodate this difference, pile caps at Bents 6 through 83 have a 4” high x 12” wide timber top “plate” installed above the cap. At Bent 26, an additional 4” high x 12” wide top plate was installed due to a misaligned pile cap (see discussion in next Pile Cap section); due to the combination of the two top plates and two stringer sizes, the top plates were notched as needed to maintain a consistent top of deck elevation. Similarly, shims were installed as needed at the shorter timber strings at Bents 25 and 27 to compensate for the height difference. There is an isolated area where Stringer 1 is slightly tilted over 10-feet with 2” wide x 4” high x 6” long section loss, likely an as-built, at Bent 40 (See Photo 23).

Photo 23 - Stringer 1 tilted at Bent 40 with 2" wide x 4" vertical x 6" long section loss.

Photo 22 - General view of timber stringers in Span 59.

Photo 24 - Stringer 14 end at bent 6 looking west.

Photo 25 – Stringers are of unequal depths at Bent 26 with extra top plate present.

Photo 26 - Some stringers at Bent 27 has timber shim in place.

At Bent 36 and Bent 41, adjustments in timber stringer alignment were observed, indicating that the contractor corrected the stringer spacing during construction. Specifically, in Spans 35 and 40, the stringer spacing had begun to deviate from the standard 1'-9" interval. However, at Bent 36 and 41, the stringers for Spans 36 and 41 were realigned to restore the standard 1'-9" spacing (see Photo 27).

Photo 27 - Stringer correction at Bent 36 looking east (fisheye view).

At Bent 23, Stringer 1 is not bearing on the pile cap; the top plate does not extend beneath the stringer leaving a 2-inch gap and exposing the drift pins. Similarly, at Bent 82, Stringers 1, 3, 5, 25, 27, and 29 have exposed drift pins with gaps of up to 1.5-inches due to a missing top plate at this location (See Photo 28).

Photo 28 - Missing shim for Stringer 1 exposing drift pins at Bent 82.

Pile caps The timber pile caps are in overall 5 – Satisfactory condition, due to the random minor to moderate defects. The pile caps typically exhibit splitting up to 1/4-inch wide and checking up to 1/2” wide x 2” deep (See Photo 33). There are splits and checks that continue intermittently, up to full length, along the pile caps but are not thru-splits based on pick probes and pile cap ends.

As mentioned in the Structural Description and Orientation section, the pile caps vary slightly in size and configuration, as follows:

• Bents 2 – 9 and 13: Pile caps are comprised of 12” wide x 16” high nominal timbers.

• Bents 10 – 12 and 14 – 83: Pile caps are comprised of 12” wide x 14” high nominal timbers.

• Bents 6 – 83: Supplemental 4” high x 12” wide timber top plate above the pile cap.

• Bents 26 and 83: Pile caps are rotated 90 degrees in comparison to the other caps of the same size. Instead of

12” wide x 14” high, the pile caps are 14” wide x 12” high. There is a second 4” high x 12” wide timber top plate at these locations. It is likely that this was installed at the time of construction to adjust for the elevation differences caused by the incorrect pile cap orientation.

Photo 29 - Typical end of pile cap looking at south end of Pile Cap 8.

Photo 30 – Typical condition of pile caps, west face of Bent 10 shown.

Although no significant structural issues were in the bent 83 pile cap member itself, it should be noted that pile cap is significantly cantilevered (up to 11.4-feet) beyond the nearest bearing pile due to the two missing piles at the south end (see Photo 31). See the Pile finding section for additional discussion.

Photo 31 – Pile Cap 83 cantilevers 11.4-feet on south end due to missing G piles. Note the dolphin cluster visible in the background.

Other isolated pile cap deficiencies and observations included:

• Bents 2, 6, 7, 8, and 9: Five pile caps were partially buried and in direct contact with the ground at the time of the inspection. Most of these caps (Bents 6, 7, 8 and 9) exhibit localized moisture staining at the base (See Photo 30).

• Bent 22: Pile cap is partially saw cut near the end.

• Bent 23 and 82: 4” x 12” timber top plate does not extend full length of cap, exposing drift pins.

• Bent 26: Additional 4” x 12” timber top plate has been notched for approximately half of the stringers (See Photo

34 and Photo 25).

• Bent 73: 1.5-inch wide gap at the pile cap splice (See Photo 34).

Photo 32 - Bent 7 Pile Cap in contact with ground.

Photo 33 – Typical check in pile cap, south face of Pile Cap 3 shown.

Photo 34 - Pile Cap 26 misoriented 90 degrees with extra 4”x12” top plate that has been notched.

Photo 35 – 1.5-inch gap in Pile Cap 73 at splice plate.

Piles The timber piles are in overall 2 – Serious condition due to the advanced deterioration and local failures that govern the overall pile element rating. The piles exhibit a variety of defects and conditions, such as: heart rot, section loss, splits and checks, non-bearing piles, and deteriorated hardware. There are localized failed/broken piles, abandoned piles and apparent “new” piles of an unknown age (additional piles installed at a bent or “sister” piles installed immediately adjacent to another pile). As per the scope, Pennoni also performed 5% destructive testing (timber cores) to better assess the timber conditions. Each of the defect types and the timber coring process are discussed separately in the subsections below. Note that the piles were covered in advanced marine growth (hard and soft) and marine life along the full height, from the high-high waterline to the channel bottom, including barnacles, mussels, starfish, anemones, algae, etc.

See also Appendix B for a comprehensive table of pile defects and locations, and Appendix A for an updated drawing with the layout of the pile locations.

Section Loss / Heart Rot

Heart rot is a type of deterioration that causes deterioration originating from the center of the pile and proceeding out radially, often leaving a fully intact outer shell. The outer shell often appears to be in good condition with normal pick penetrations, which can make heart rot very difficult to identify in the field. Depending on the severity of the rot, these piles can sometimes sound hollow when sounded with a hammer. Heart rot is usually first observed at pile ends or in areas of advanced deterioration that has extended through the outer shell. For the purposes of this report and ease of field investigation, the section loss due to heart rot was measured as an estimated percentage of the pile diameter, not the estimated cross section remaining.

The piles at Manchester Pier exhibit widespread heart rot throughout the structure, causing advanced deterioration and localized pile failures. A total of approximately 542 piles were inspected, of which 109 exhibited notable defects.

• Over 15% of the piles exhibit a minimum of 30% section loss due to heart rot.

• 73 piles exhibit between than 30% to 95% section loss due to heart rot.

o Of these piles 53 exhibit over 75% section loss (See Photo 38 to 45).

o Of these piles 13 exhibit between 50% to 75% section loss (See Photo 36).

o Of these piles 22 exhibit between 30% to 50% section loss (See Photo 37).

• 11 piles exhibit 100% section loss (see Photo 41).

Please see Appendix B for a comprehensive table of pile defects and locations.

As mentioned above, heart rot cannot typically be observed on the outside pile shell. Furthermore, the piles at Manchester Pier are covered nearly full height with advanced hard and soft marine growth, which also obscures visual identification of defects and reduces the effectiveness of sounding the timber piles for hollows with a hammer, as the hard marine growth dulls the echo. Heart rot was typically identified at areas of extreme deterioration where the outer shell was failing, non-bearing or offset piles (the top of the piles and interior heart rot were exposed), and at piles with splits, checks or other section loss that penetrated into the heart rot from the outer surface. The heart rot was predominantly identified by the last method - probing smaller checks and splits visible from the outside. Inspectors use stick rulers and picks (awls) to penetrate into and laterally at the defects (see Photo 37 and Photo 36). It should be noted that some of these defects were very small and would not be fully measured/probed. The inspectors used engineering judgement to assign an estimated section loss at these locations. At some locations, the piles sounded hollow but there were no surface defects to expose or confirm the heart rot.

Photo 38 – Bent 29, Pile G-Battered: 100% section loss at low water line.

Photo 39 –Bent 16, Pile D: Rotted with 90% section loss at channel bottom.

Photo 40 – Bent 34, Pile D-Plumb: 1” shell remaining for full height, estimated 90% section loss.

Photo 41 –Bent 51, Pile G-Plumb: 100% section loss.

Photo 36 - Bent 20, Pile D-Plumb: 1/2-inch wide split with 9-inches of penetration, estimated 30% section loss.

Photo 37 – Bent 26, Pile F: Estimated 60% section loss in tidal zone.

Non-bearing Piles

Over 60 piles at Manchester Pier exhibit non-bearing or partially bearing conditions, primarily due to misalignment and deterioration. The piles are non-bearing due to gaps between the pile and the cap. The gaps are typically small, less than 1-inch, but varying in height up to 3-inches high at random locations. There were 2 locations, Bent 82, Pile B and Bent 83, Pile B, where piles were non-bearing and missing the drift pin, allowing the pile to sway in the current (See Photo 49). The larger gaps typically extend across the full cross section of the pile, while smaller gaps may only create a partial-bearing conditions where only a percentage of the pile is disengaged.

Some of the piles are also non-bearing due to being installed off-center from the pile cap. The piles are typically 12-inch diameter. However, pile sizes vary throughout and piles with larger diameters (for example, 14-inch piles) sometimes extend beyond the face of the pile cap on one or both sides, but are not considered non-bearing.

Please see Appendix B for a comprehensive table of pile defects and locations.

Photo 42 –Bent 56, Pile F: 90% section loss.

Photo 43 – Bent 60, Pile F-Original: 100% section loss in tidal zone with sistered pile.

Photo 45 – Bent 75, Pile E-Original: Failed and disconnected with 80% section loss.

Photo 44 –Bent 64, Pile D-Battered: Estimated 90% section loss in tidal zone.

Photo 48 - Bent 37, Pile D-Battered: 100% non-bearing with 3-inch gap exposing drift pin.

Photo 49 - Bent 83, Pile B-Plumb and Battered: 100% non-bearing with 2" gap with no drift pin.

Photo 50 – Bent 3, Pile E: Partially-bearing pile, approximately 50% bearing due to misalignment.

Photo 47 - Bent 46, Pile D-Plumb and D-Battered: Non-bearing stub pile.

Photo 46 - Bent 45, Pile F: Partially bearing stub, approximately 20% bearing.

Other Piles Defects and Conditions

The timber piles exhibit splits, checks, crushing, rot and other defects throughout, typical for timber piles of this age exposed to the elements. These defects are typically minor to moderate in severity. The other defect types and examples of each are listed below. As described above, these defects are sometimes associated with heart rot and partially bearing condition due to loss of section of the top of the pile. See Appendix B for a comprehensive list of defects and locations.

• Splits/checks – There are seven piles that exhibit minor to wide splits and thru splits up to nearly the full height of the pile (See Photo 51 and Photo 52).

o Bent 18, Pile G; Bent 44, Pile E; Bent 47, Pile E; Bent 47, Pile G; Bent 65, Pile G; Bent 82, Pile C; Bent 83, Pile C.

• Crushing – There are three piles that exhibit minor crushing to the top of the pile (See Photo 53).

o Bent 53, Pile G; Bent 61, G-Plumb and G-Battered.

• Shakes – Bent 44, Pile F has minor to moderate shakes with peeling of the outer pile shell.

• Cut piles – Three piles have been cut in the tidal zone, presumably to install the adjacent sister pile.

o Bent 28, Pile D-Battered; Bent 43, Pile D-Battered; Bent 77, Pile G-Battered.

• Jackets – There is a single jacketed pile at Bent 15, Pile G. The steel jacket extends approximately 3-feet above the channel, has an approximately 7-inch wide annulus filled with concrete, and exhibits moderate deterioration at the top.

The pile hardware exhibits varying degrees of deterioration. There are wire rope wraps at the top of the plumb and battered piles. The wraps exhibit widespread deterioration and failure throughout the pier. Many wire wraps are in severe condition, with up to 100% section loss, compromising the alignment and connection. Bolts securing the plumb and battered piles exhibit surface corrosion with minor section loss throughout the pier.

There are 21 piles connected to the pile cap with a “pile stub” at the top. Although this is not a defect itself, it is a condition of note as this type of detail is commonly used when repairing/replacing deteriorated pile sections. It is likely that these stubs are part of past repairs to previously observed defects (non-bearing or deteriorated piles), but this cannot be confirmed as there no original or repair drawings available. The stubs vary in configuration and size, but typically consist of a short length of a square timber. Similar to the other piles, some of the stubs are not fully bearing due to gaps or misalignment (see Photo 47).

Photo 51 - Bent 44, Pile E: Top of pile split, 15% section loss and bearing loss.

Photo 52 - Bent 82, Pile C: Split, 1/2" W x 6" D, at top of pile.

Photo 53 - Bent 61, Pile G-Plumb and Battered: Crushing at top causing 10% section loss and bearing loss.

Photo 54 – Bent 28, Pile D-Battered: Pile cut in tidal zone.

Photo 55 – Bent 77, Pile G-Battered: Pile cut in tidal zone.

Photo 56 - Bent 29, Pile E: Stub, 18" high.

Timber Core Sampling

As part of the inspection scope, Pennoni completed a minimum of 5% Level III inspection by timber core sampling. The purpose of the partially destructive evaluation was to better understand and assess the condition of the piles, which are critical to the structural integrity of the pier. The inspectors collected “pencil core” samples for visual assessment of the extent of deterioration. The scope excluded laboratory testing, which typically requires larger samples. The inspection scope included sampling on 10-15 piles, or approximately 5% of the 275 in-water piles.

The Pennoni inspection team collected a total of 22 samples from the 12-inch (typical) diameter piles. The samples were spread across various environmental zones (inshore, inter-tidal, and offshore), as well as throughout the water column (dry, high waterline, tidal zone, mid-height, channel bottom). The cores were 0.200” diameter x 7” long and were obtained using a standard increment borer. The cores were analyzed visually while on-site for length, discoloration, and visible deterioration. These parameters allude to the presence of rot, decay, and marine borer damage. Additional scientific testing would be necessary to confirm the exact cause (type of rot, mariner borer, etc.) of the observed pile deterioration and was beyond the scope of this inspection. Each parameter was assigned a corresponding rating, and the individual ratings were summed for a maximum total sample rating of 10 at each pile. See the summary table included here and also in Appendix C.

Env.

Zone Bent Pile*

Height in water column

Length of sample

(in)

Discoloration

(in)

Visible

Deterioration

(in)

Length

Discoloration

Visible

Deterioration

Overall

Rating

Inshore 9 G Dry 7.0 1.25 0.75 100 17.9 10.7 10

Inter-tidal

Zone

13 F Dry 7.5 6.25 1.75 107 83.3 23.3 7

14 D HWL 7.0 3.75 2.25 100 53.6 32.1 7

14 G HWL 0.875 0.875 0.875 12.5 100 100 0

15 G HWL 7.25 5.0 4.25 104 69.0 58.6 6

16 G CB 7.25 2.5 1.75 104 34.5 24.1 9

17 F TZ 7.25 6.25 4.5 104 86.2 62.1 5

17 F HWL 7.5 5.0 4.0 107 66.7 53.3 6

17 F CB 7.25 1.5 0.5 104 20.7 6.9 10

17 E HWL 6.0 5.25 4.75 85.7 87.5 79.2 3

17 E CB 0.625 0.625 0.625 8.93 100 100 0

Offshore

30 G-P WL 4.5 4.5 3.25 64.3 100.0 72.2 3

38 F CB 5.0 4.5 4.5 71.4 90.0 90.0 3

42 D-B MH 5.0 4.25 3.75 71.4 85.0 75.0 3

47 E MH 4.75 4.75 4.5 67.9 100 94.7 3

52 E MH 6.0 4.5 3.0 85.7 75.0 50.0 5

58 E CB 6.0 4.0 4.25 85.7 66.7 70.8 5

64 E HWL 5.25 5.25 5.25 75.0 100 100 2

70 E CB 4.25 4.25 2.5 60.7 100 58.8 3

76 A-P HWL 5.0 3.75 3.75 71.4 75.0 75.0 4

79 G-B HWL 4.75 3.5 3.75 67.9 73.7 78.9 4

82 D MH 4.25 4.25 4.25 60.7 100 100 1

Table 3 - Timber Core Sample Rating Calculation

Overall, the timber core sampling correlated well with the other inspection findings. The samples demonstrate a range of defect conditions throughout the majority of the pier length as well as vertically through the water column. They confirm the presence of interior deterioration and likely timber treatments. The limited inshore sampling correlated with the field observations at the inshore piles, which were generally in good condition and are protected from the tidal swings (See Photo 57). The inter-tidal zone piles, subject to daily wet-dry cycles, demonstrated a wider range of conditions (see Photo 58). The average rating for the tidal zone piles was 5.30, reflecting the harsh environmental conditions and variable structural health of the timber in this zone. These piles exhibited deterioration levels varying from minor discoloration with a rating of 10 to significant section loss with a rating of 0. This range of conditions was also observed throughout the water column. These variations demonstrate how the isolated timber cores may not capture a partial height internal defect. The outshore piles, continuously submerged in water, were the most deteriorated among the three zones, with an average rating of 3.27 and no sample rated over a 5. These findings indicate more extensive deterioration in the offshore piles compared to those in other zones. The absence of high-rated samples in this zone supports the conclusion that on-going repairs will likely be required of the future lifespan of the Pier.

The pile condition ratings were determined based solely on visual indicators, including length, discoloration, and signs of deterioration such as fraying or crumbling. The precise nature and extent of the degradation cannot be confirmed without further laboratory analysis, as these ratings cannot provide the underlying causes of deterioration. While this visual assessment process provides a standardized method to translate qualitative observations into quantifiable data, it is inherently limited in scope. To fully understand the structural capacity of the piles and the impact of the observed deterioration, additional scientific testing, such as light and stereo microscopy, is recommended.

See Appendix C for additional discussion of the coring methodology, coring procedure, coring assessment, findings, discussion and conclusions, as well as photos of all the pile samples.

* P = Plumb pile, B = Battered pile

Photo 59 - Diver taking timber core sample underwater.

Photo 58 - Bent 64, Pile E at HWL timber core sample.

Photo 57 - Bent 9, Pile G timber core sample.

Fender Piles

Although the fender piles were not included in the scope of the inspection, we have included the basic notes below and sample photos for completeness and comparison to the other pile conditions. Field observations indicate that they exhibit many of the same defects identified in the main structural piles. Significant deterioration was observed, particularly related to heart rot, structural connections, and hardware integrity to the fender piles and dolphin clusters.

• Heart Rot: Extensive heart rot was evident across most fender piles. Only four fender piles along the south side of the pier were unaffected. Along the north side, only one pile was found without heart rot present.

• Wire Wraps and Connection Hardware: Throughout the fender piles and dolphin clusters, wire wraps displayed 100% section loss, indicating complete failure. The U-bolts securing the fender piles to the pier were often either broken or missing.

• Dolphin Clusters: The two dolphin clusters, located at the north and south outshore corners of the pier, also demonstrated significant deterioration. Specifically, all but two piles in the north dolphin cluster had visible heart rot, while all in the south dolphin cluster had heart rot present.

Photo 60 - Top of piles in the south dolphin. Note: All piles have heart rot present.

Photo 61 - Typical fender pile conditions - missing hardware, missing piles, sistered piles.

Cross Bracing The timber cross bracing is in overall 1 – Critical condition due to widespread advanced deterioration and local failures.

As mentioned previously, the cross bracing is located at the outshore end of the Pier, with a combination of lateral…