September 10, Anne Arundel County Department of Public Works Heritage Office Complex 2664 Riva Road, Mail Stop MS-7301 Annapolis, Maryland 21401

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1 Anne Arundel County Department of Public Works Heritage Office Complex 2664 Riva Road, Mail Stop MS-7301 Annapolis, Maryland Attn: RE: Structural Investigation of the Franklin Manor Bulkhead Chesapeake Drive, Churchton, Maryland AA County Project Number H Purchase Order Number OO Century Project Number Mr. Anderson: Century Engineering, Inc. (CEI) recently visited the Franklin Manor Bulkhead on May 14 th and 15 th, 2014 in order to inspect and document the condition of the structure. This letter provides a brief description of the bulkhead construction, along with our observations, opinions, and recommendations. Additionally, we have provided a list of civil engineering considerations that pertain to the recommendations, as well as an estimation of probable construction costs. Description The timber bulkhead was built in the 1930s and modified in Some repairs were performed in recent years. The bulkhead runs parallel to and is immediately adjacent to Chesapeake Drive. It is approximately 700' in length and 8'-tall with 117 solder piles spaced at 6'. At low tide approximately 3' of the bulkhead is below water. Every sixth solder pile is braced by two 2x10 struts that extend 16' into the bay and connect to plumb piles located 8' and 16' from the bulkhead. Between these three-pile configurations every other plumb pile is buttressed by a battered pile. 6x8 timber wales span between the backsides of the solder piles at the top of the bulkhead and just below the low water line. An additional 6x8 horizontal wale spans between the soldier piles along the top front side of the bulkhead. Original timber sheet piling spans vertically between the horizontal wales to support earth fill and the adjacent roadway. New timber sheet piling has been driven directly behind the original to repair a failure caused by a storm. Continuous 2x alignment boards and cap boards run along the top rear face and top of the sheet piling. Several storm drains extend through the bulkhead. The attached drawing provides more detail on the bulkhead construction. Observations The original timber sheet piling is severely deteriorated and in some places missing, exposing the newer sheet piling behind (See Photos 2 and 3). The newer sheet piling is in satisfactory to good condition. Marine growth is typical at and below the waterline of all structural members. The piles are generally in poor to critical condition. Cross-section reduction or bottlenecking generally ranges from 10% to 75% loss, with local areas of 100% loss (See Photos 4 and 5). Typically this section loss is near the waterline or splash zone, but in some piles it continues

2 Page 2 up to the top of the pile. The underwater portions of the piles were not visually inspected. Ice pick penetrations into the piles are typically ¼"- ½". Core samples were taken from nine original piles and one newer pile. The core samples of the original piles revealed that the outer ½ ± is deteriorated and the interior is in satisfactory condition. We did not observe any significant voids or soft areas that would suggest interior decay or the presence of marine borers. Creosote treatment penetration is good in all of the original piles. The core sample of the one newer pile indicates good preservative penetration and good condition of the wood. Refer to Photos 13 through 24 for pictures of the core samples. The plumb piles are out of alignment with each other by as much as 1' inboard and outboard and several piles are out of plumb by up to 6" outboard over 4'± (See Photo 6). Many vertical piles are bowed due to the lateral earth pressure. The piles are split vertically at many of the hardware connections. Brown rot (macroscopic decay from fungal attack of moist wood) and section loss accompany the splits in many locations. The hardware is heavily corroded and "flowering" at many locations. The hardware connecting the horizontal struts to the three-pile configurations is typically loose and severely rusted or missing. Several of the struts are detached from the pile (See Photos 7 and 8). The condition of the original wales ranges from fair to poor. Several new wales installed during repairs are in satisfactory to good condition (See Photos 9 and 10). The original front and backside wales exhibit splitting and rot with vegetation growing out of the member. Several wales are bowed or deflected outwards between piles. Ice pick penetrations are as much as 4" deep in rotted areas. The wale lap joint conditions range from fair to poor with some completely failed (See Photo 11). Hardware used to connect the wales to the piles is severely corroded (See Photo 12). The lower wale was below the waterline and could not be inspected. Opinions In our opinion, the overall condition of the bulkhead is poor. Although the bulkhead has not failed, its load carrying capacity has been significantly reduced. Brown rot and splitting are prevalent in the wales, but the deterioration of the piles and struts appears to be the result mechanical abrasion wear from wave action, ice, and debris in the water. Given the age of the piles it is likely that soft rot could be present though checking for this was beyond the scope of this report. Soft rot is a slow deterioration of the wood cell structure caused by bacteriological activity inside the wood cells. The fungal microorganism that causes this requires low oxygen levels, low light and cooler water temperatures. The ideal environment for soft rot to occur is below the splash zone down to the mudline. Soft rot is not detectable through normal inspection procedures. Microscopic analysis and strength testing is required to confirm the presence of soft rot. We estimate the remaining service life to be five years under normal circumstances. Extreme weather or heavily loaded trucks on Chesapeake Avenue are likely to create local failures and decrease the service life of the bulkhead. Recommendations Short Term Recommendations: If replacement of the bulkhead is not scheduled to occur with the next year, we recommend replacing the broken or missing timber struts including the

3 Page 3 hardware. Severely corroded hardware at existing struts should be replaced also. Piles that are split or decayed at the connections shall be modified with splints, blocks and/or strapping in order to provide proper transfer of force from the strut. Long Term Recommendations: We recommend replacing the existing bulkhead. Three options are provided below: 1. In-Kind Replacement. Replace existing timber bulkhead with a similar timber system. 2. Stone Revetment. Replace the timber bulkhead with a stone revetment, like those which flank each side of the current bulkhead. The top of existing timber bulkhead would be demolished but the lower portion would be abandoned in place. 3. Steel Sheet Piling. Install new steel sheet piling behind the existing bulkhead and remove the existing timber components. Engineer's Approximation of Probable Construction Costs We have estimated the construction cost of the replacement options using rough quantities and unit prices found on RS Means Online Construction Costs. Option Item Unit Quantity Unit Price Estimated Cost 1 In Kind Replacement Engineering LS 1 $ 30,000 $ 30,000 General Conditions LS 1 $ 25,000 $ 25,000 Mobilization, Demobilization LS 1 $ 25,000 $ 25,000 Demolition SF 5,600 $ 10 $ 56,000 Civil Work LS 1 $ 80,000 $ 80,000 Timber Piles VLF 4,400 $ 50 $ 220,000 Sheeting & Wales SF 5,600 $ 20 $ 112,000 $ 548,000 2 Stone Revetment Engineering LS 1 $ 30,000 $ 30,000 General Conditions LS 1 $ 25,000 $ 25,000 Mobilization, Demobilization LS 1 $ 25,000 $ 25,000 Demolition SF 1,400 $ 10 $ 14,000 Civil Work LS 1 $ 80,000 $ 80,000 Stone TONS 4,000 $ 85 $ 340,000 $ 514,000

4 Page 4 3 Steel Sheet Piling Bulkhead Engineering LS 1 $ 30,000 $ 30,000 General Conditions LS 1 $ 25,000 $ 25,000 Mobilization, Demobilization LS 1 $ 25,000 $ 25,000 Demolition SF 5,600 $ 10 $ 56,000 Civil Work LS 1 $ 80,000 $ 80,000 Steel Sheet Piling (8' retained) LF 700 $ 400 $ 280,000 $ 496,000 Civil Considerations Repair and/or replacement of the bulkhead will require coordination with area residents and with Anne Arundel County. We have identified the following issues that will need to be considered: 1. Traffic and Construction Staging a. The existing pavement width is 20± feet. Residential and emergency access to the existing homes adjacent to the work area will need to be provided during the repair period while all other traffic should be detoured around the work area b. Contractor staging areas can be located at the existing park to the west of the bulkhead 2. Surrounding Properties, Roads, and Utilities a. Existing utilities within the Chesapeake Drive right of way consist of storm drain and sanitary sewer. b. BGE, Verizon and Cable lines are overhead on the landward side of the Chesapeake Drive. c. There are two guy poles that will need to be relocated/adjusted as a result of these repairs. They are located at the intersections of Exeter Street and Chesapeake Drive and Franklin Boulevard and Chesapeake Drive. This work will need to be coordinated with BGE. d. The Contractor will need to contact Miss Utility prior to the start of construction to determine if there are other public utilities are within the work area. e. Existing sanitary sewer and storm drain lines in Chesapeake Drive will need to remain operational and any extensions of the storm culverts discharging into the bay will need to be performed by the Contractor. f. It is our opinion that the sanitary sewer main and house connections will not be impacted as a result of the repairs as they are on the landward side of Chesapeake Drive.

5 Page 5 g. Any area of paving that are within the work area or damaged as a result of the bulkhead repair should be milled for a depth of 2 and overlaid with a County approved hot mix asphalt section. h. If repairs require the Contractor to work outside of the existing paving section, and onto private property, temporary construction easements may be necessary and must be obtained from the appropriate home owner. This will be the responsibility of Anne Arundel County. 3. Plans and Permitting a. A licensed civil engineer must prepare plans for the repair of the bulkhead. These will include Public Storm Drain Plans, Erosion & Sediment Control Plans, Grading Plan, Site Plan and Stormwater Management Plans. A waiver of stormwater management will be requested as this work is considered maintenance and repair. b. A structural design for the new bulkhead will be needed for permitting and construction purposes. A licensed structural engineer will need to be engaged to provide this service. c. Four to five soil borings must be taken immediately behind the bulkhead to assess subsurface conditions. Soil samples must be collected and evaluated in a laboratory to determine engineering characteristics. A licensed geotechnical engineer will need to review these results and make recommendations to guide the design and construction of the new bulkhead. d. Permits required for the repair of the bulkhead will include a Grading Permit, Building Permit, Maryland Department of the Environment and Army Corp of Engineers permits for work within Chesapeake Bay. Approvals will also be needed from the Chesapeake Bay Critical Area Commission and a National Pollutant Discharge Elimination Permit (NPDES). e. Plan and permitting services will take approximately 9-12 months to obtain approvals necessary to start construction. General Exclusions and Limitations The observations, opinions and recommendations stated in this report are based upon data obtained by visual observation of the building as it existed on the date and time of our inspection. This report does not and can not include any observations, opinions and recommendations for hidden conditions and any uninspected conditions. The nature, extent and effect of any hidden conditions or uninspected conditions may not become evident until a future date and may have a detrimental effect on the building. No evaluation has been made of any other improvements not specifically stated herein. Our scope of work specifically excluded the following items: Disturbing, moving or relocating the property of others.

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7 Page 7 Photographs

8 Page 8 Photo 1: Bird's Eye View from South. Photo 2: Original sheet piling deterioration at east end.

9 Page 9 Photo 3: New sheet piling behind original failed timber sheet piling. Photo 4: Typical pile in poor condition with evidence of bottlenecking.

10 Page 10 Photo 5: Typical timber piles in critical condition with evidence of bottlenecking. Photo 6: Piles out of alignment with one another.

11 Page 11 Photo 7: Broken, detached and loose struts. Photo 8: Loose, failed hardware and section loss in strut & pile. Typical marine growth and deteriorated sheet piling.

12 Page 12 Photo 9: New pile & new frontside horizontal wale at pile line 82. Photo 10: Rotted and missing backside wale.

13 Page 13 Photo 11: Splitting and rot at lap joint of frontside wales. Photo 12: Severely corroded hardware and splitting wood at frontside wale lap joint.

14 Page 14 Photo 13: Core Sample 8A Photo 14: Core Sample 20B Photo 15: Core Sample 32A Photo 16: Core Sample 44B Photo 17: Core Sample 56A Photo 18: Core Sample 68B

15 Page 15 Photo 19: Core Sample 81A Photo 20: Core Sample 82B Photo 21: Core Sample 92B Photo 22: Core Sample 104A, Outer Part Photo 23: Core Sample 104A, Inner Part

16 Page 16 Photo 24: Timber Pile Core Samples

17 132'± NEWER CONTINUOUS 2x PT CAP BOARD NEWER CONTINUOUS 2x PT ALIGNMENT BOARD NEWER PT T&G TIMBER SHEET PILE A B ORIGINAL FRONTSIDE & C D BACKSIDE TOP WALES ORIGINAL BATTERED TIMBER PILE BEYOND ORIGINAL TIMBER SOLDIER 6' MLW± ORIGINAL LOWER WALE ORIGINAL T&G TIMBER SHEET PILING 3'± AT LOW TIDE ORIGINAL TIMBER BRACING PILES ORIGINAL OR NEWER 2x10 STRUT EACH SIDE OF PILES A B C D 0 STONE REVETMENT 24"ر HDPE PIPE W/ 2-2x10 BOLTED TO SHEET PILING ABOVE PIPE PLUMB TIMBER BRACING ABANDONED SAFE 4 10 PILES & 2x10 STRUTS Sim CORE SAMPLE TAKEN TIMBER SHEET PILING TIMBER WALES, TYP BATTERED TIMBER PILE, TYP PLUMB TIMBER PILE, TYP CORE SAMPLE TAKEN MATCHLINE A B C D S.1 2 Plan 1 1" = 10'-0" 1 Typical Section 3/8" = 1'-0" 288'± A B C D MATCHLINE "ر TCP W/ 2-2x10 BOLTED TO SHEET PILING ABOVE PIPE. INLET LOCATED ACROSS ROAD. CORE SAMPLE TAKEN TIMBER SHEET PILING TIMBER WALES, TYP BATTERED TIMBER PILE, TYP PLUMB TIMBER PILE, TYP CORE SAMPLE TAKEN PLUMB TIMBER BRACING PILES & 2x10 STRUTS CORE SAMPLE TAKEN CORE SAMPLE TAKEN MATCHLINE A B C D 3 Plan 2 1" = 10'-0" 1 S.1 276'± TIMBER SHEET PILING TIMBER WALES, TYP 2 NEWER 2x10s, 1 ABOVE AND 1 BELOW STRUT, EACH SIDE 24"ر RCP JUST BELOW LOWER WALE. 2x10 BOLTED TO SHEET PILING ABOVE PIPE. 18"ر HDPE PIPE W/ 2-2x10 BOLTED TO SHEET PILING ABOVE PIPE, 1-2x10 BOLTED BELOW. DRAINAGE INLET LOCATED ACROSS STREET. 18"ر CMP FROM DRAINAGE INLET ACROSS STREET. A B C D MATCHLINE 4 Plan 3 1" = 10'-0" BATTERED TIMBER PILE, TYP PLUMB TIMBER PILE, TYP CORE SAMPLES TAKEN NEW PLUMB PIPE 18"± FROM A-PILE CORE SAMPLE TAKEN PLUMB TIMBER BRACING 70 PILES & 2x10 STRUTS CORE SAMPLE TAKEN 1 S.1 Sim STONE REVETMENT This sheet is not intended to be an accurate as-built drawing. It is intended to document the general arrangement and structural condition of the bulkhead elements at the time of the inspection. This drawing is part of an inspection report dated 6/9/14. Color Purple Cyan Green Yellow Orange Red Magenta Black Descr. Excellent V. Good Good Satis. Fair Poor Failed/Missing Not Inspected PILE CONDITION RATING KEY Condition Criteria New No problems. Some very minor problems. Minor problems. Capacity unaffected. Minor section loss. Capacity unaffected. Major to severe section loss. Capacity reduced. No capacity, missing or out of service beyond repair. Not inspected or rated. Anne Arundel County, MD Franklin Manor Bulkhead Condition Assessment Designed by: MEP Drawn by: MEP Checked by: WBR Proj. No.: Status: Inspection Issued: June 9, 2014 S.1 6/9/ :36:37 AM

18 CONCEPTUAL DESIGN ONLY - NOT FOR BID OR CONSTRUCTION FILTER FABRIC 2' - 4" 16' - 0"± 2' - 0" CONTINUOUS CHANNEL CAP 2 1 CLASS 3 RIP RAP 4' - 6"± STEEL SHEET PILING 4' - 6"± MLW± MLW± COBBLE -SIZE STONE BEDDING 1' - 6" 3' - 0"± 3' - 0"± CUT-OFF & ABANDONED TIMBER PILE, TYP 4' - 0" CUT-OFF & ABANDONED TIMBER SHEET PILING FILTER FABRIC 4' - 0"± 2 Option 2 - Stone Revetment 3/8" = 1'-0" 3 Option 3 - Steel Sheet Piling 3/8" = 1'-0" Franklin Manor Bulkhead Replacement Options Des: MEP Dwn: MEP Chk: WBR Status: Inspection Issued: June 26, S.2 6/26/14 10:58:11 AM