Bridge Inspection Summary Memo_9-25-25 (ID 3454891).pdf

Barton & Loguidice

Bridge Inspection Summary Memo (ID 3451582)

Memo To: Travis Ewald, P.E.

Commissioner Orange County Dept. of Parks & Recreation

Date: 9/25/2025

From: Byron Raych, P.E.

Senior Managing Engineer

Project No.: 1724.010.001 Phase No.: 2A

Re: Plum Point Lane over CSXT (BIN 5523830) Bridge Inspection and Repair Recommendations Summary Memo

Introduction

The Plum Point Lane Bridge over CSXT (BIN 5523830) is a 3-span simply supported structure that is located in the Town of New Windsor, Orange County. The bridge carries Plum Point Lane over CSXT’s River Line and serves as the single access point to Orange County’s Plum Point Park, which is located along the west bank of the Hudson River.

The bridge was originally built in 1930, however, a major rehabilitation was completed in 1996 including complete superstructure replacement and widening of the timber piers. The bridge contains multiple steel girders with a concrete filled steel grid deck founded on concrete abutments and timber piers supported on concrete stem walls and footings. Each pier consists of two timber frames, both of which contain five vertical and two diagonal timber columns bearing on a concrete stem wall and footing. The timber columns have various cross-bracing members in the transverse and longitudinal directions. See attached Photos 1 and 2 for the general configuration of the bridge and piers.

The existing bridge sustained damage from a fire during August of 2024. The fire is believed to have started at ground level and a majority of the fire damage was to the timber pier frames at Pier 1. NYSDOT inspected the bridge on September 4, 2024 and they issued a Red Structural Flag which resulted in closure of the bridge until additional inspection, evaluation and/or repairs to the structure could be completed. The bridge has remained closed to traffic since September 2024. Orange County hired Barton & Loguidice (B&L) to inspect the bridge, assess the bridge conditions, complete a Level 1 Load Rating of Pier 1 and provide repair recommendations for the structure. The remainder of this memo will provide a summary of the conditions encountered during the inspection and provide repair recommendations for the structure.

Bridge Inspection and Repair Recommendations Summary Memo 9/25/2025

Bridge Inspection Summary Memo (ID 3451582)

Bridge Inspection Summary

B&L inspected the bridge on June 13, 2025 to further evaluate the damage sustained during the fire and to confirm the overall condition of the structure. The physical inspection was completed from ground level using ladders to inspect the lower portions of the timber pier frames. The upper portions of the piers were not accessible for hands-on inspection. A drone was utilized to obtain video/photographs of the upper portions of the piers and it was noted that the visible fire damage appeared to be fairly consistent throughout a majority of the Pier 1 timber members.

The fire damage occurred at Pier 1. Pier 1 consists of two timber pier frames/trestles with one frame supporting the Span 1 superstructure and the second frame supporting the Span 2 superstructure. Each timber frame consists of five vertical columns (C1, C3-C5 and C7) along with two diagonal columns (C2 and C6). The columns support a steel cap beam that the steel superstructure rests on. The two frames are connected with timber bracing members.

There is evidence of fire damage, rot, cracking and checking of the timbers throughout all of the columns on Pier

1. The most significant area of damage and deterioration encountered during the inspection is at the base of Column C2 Span 1 where 100% section loss exists at the base of the column (See Photo 3). Additionally, there is significant fire damage near to the top of Columns C5 and C6 Span 2 directly beneath the steel cap beam. The fire damage at this location has resulted in approximately 50% section loss to C5 and C6 along with up to 75% section loss of the diagonal cross brace (See Photo 5 & 6). Various other members throughout Pier 1, especially Columns C1, C2, C3, and C4 at Span 1 have vertical checks up to 4 inches deep along much of their total length (See Photo 4). All other timber columns and bracing members at Pier 1 exhibit areas of charring from the fire.

The inspection included visual inspection of the surface conditions; however, non-destructive or forensic testing of the members to determine their load carrying capacity or underlying fire damage was not within the scope of the inspection. It is assumed that several of the columns that have surface charring and deep vertical checks have reduced load carrying capacity.

The remainder of the bridge is in fair condition with a majority of the bridge conditions found to be similar to as described in the most recent NYSDOT Biennial Bridge Inspection. The concrete bridge deck has some cracking and spalling along the top wearing surface and on the underside of the deck. The steel superstructure beams and steel cap beams exhibit some paint failure with minor steel corrosion at the bearings and beam ends. There is no measurable deterioration of the timber and steel elements at Pier 2.

Recommended Repairs

Due to the conditions of the timber columns at Pier 1, the results of the Level 1 Load Rating, and the assumed reduction of the structural capacity of the timbers due to the fire damage, temporary or permanent repairs are recommended prior to reopening the bridge to limited vehicular traffic.

Bridge Inspection Summary Memo (ID 3451582)

Temporary Pier Repairs:

The temporary repairs would include installation of temporary columns to supplement the capacity of Columns C1 through C4 at Pier 1 Span 1 and Columns C5 through C7 at Pier 1 Span 2. The temporary columns would be structural steel shapes (HSS, HP or similar) or a pre-fabricated steel shoring frame placed directly on the concrete pier stem wall. The temporary columns would be shimmed and attached to the existing steel cap beam. The following preliminary repair procedure is recommended, however, additional analysis, design and detailing of the temporary columns by a NYS Professional Engineer is required prior to construction of the repairs.

1. Install additional timber or steel bracing between Columns C1 and C3 on Pier 1 Span 1 and Pier 1 Span 2 pier frames

2. Remove Column C2 and timber cross bracing between C1 and C3 at Pier 1 Span 1

3. Install Temporary Columns on inboard Side of C1 and C3

4. Install Temporary Cross Bracing Between Temporary Columns

5. Repeat Steps 1 thru 3 for Column C4 at Pier 1 Span 1 and Columns C5, C6 and C7 at Pier 1 Span 2

The estimated construction cost for the temporary repairs is $ 150,000. It is noted that additional costs for Engineering and Railroad Permitting/Flagging are not included in this cost.

Temporary Pier Repair Sketch

Bridge Inspection Summary Memo (ID 3451582)

Permanent Pier Repairs:

Permanent repair of the piers would include complete replacement of both timber pier frames, including all columns and cross bracing, at Pier #1. It is recommended that the timber pier frames be replaced with steel pier frames to provide a longer service life and to minimize the potential for future fire damage. The replacement pier frames could consist of structural steel columns (HSS, HP or similar shape) with steel cross braces or pre-fabricated steel pier frames. It is anticipated that the pier replacement could be completed sequentially using temporary columns placed on top of the concrete pier stem walls to provide temporary shoring without encroaching into the railroad clearance window. In addition to complete replacement of Pier #1, additional longitudinal braces need to be installed at Pier #2 to increase the capacity of the timber frames. Additional analysis, design and detailing of the temporary columns by a NYS Professional Engineer is required prior to construction of the repairs.

The estimated construction cost for the permanent repairs is $ 450,000. It is noted that additional costs for Engineering and Railroad Permitting/Flagging are not included in this estimated construction cost.

Town of New Windosr, Orange County, NY

June 2025

Plum Point Lane over CSXT River Line Bridge Inspection Photos

Photo 1 - Bridge Elevation View

Photo 2 - Pier Elevation View

Plum Point Lane over CSXT River Line Bridge Inspection Photos

Photo 3 - Column C2, Pier 1, Span 1 - 100% Section Loss at Base of Column

Photo 4 - Column C4, Pier 1, Span 1 - Charred Conditions and Longitudinal Checks/Cracks

Plum Point Lane over CSXT River Line Bridge Inspection Photos

Photo 5 - Columns C5 & C6, Pier 1, Span 2 - Fire Damage and Section Loss at Columns and Bracing

Photo 6 - Columns C5 & C6 Pier 1, Span 2 (on right) - Column and Cross Bracing Fire Damage and Deterioration