Jacob_Riis_Park_Seawall_UW_Inspection_Report_DRAFT_-_KBP_comments.pdf

INSPECTION REPORT

JACOB RIIS PARK SEAWALL

JAMAICA BAY, ROCKAWAY, NEW YORK

OCTOBER, 2014

FOR:

VHB, Inc.

50 Main Street

White Plains, NY 10606

ATLANTIC ENGINEERING, LLC

170 KINNELON ROAD, SUITE 39

KINNELON, NJ 07405

Phone (973) 838-3100

Fax (973) 838-2980

PREPARED BY:

“A JMT Company”

DRAFT

TABLE OF CONTENTS

PAGE

LOCATION MAP/AERIAL PHOTO 1

INTRODUCTION 2

SUMMARY OF FINDINGS 2

CONDITION TABLES 3

DRAWINGS 20

SOUNDINGS 40

CONCLUSIONS & RECOMENDATIONS 44

PHOTOGRAPHS 45

-1-

LOCATION MAP

SITE

AERIAL PHOTO

SITE

INTRODUCTION

Atlantic Engineering, LLC was contracted by Vanasse Hangen Brustlin, Inc. (VHB, Inc.) to perform a

Type-1 inspection of the Jacob Riis Park Seawall in Rockaway, Queens, New York. The seawall is located to the north of the Jacob Riis Parking Lot along Beach Channel Drive and faces Jamaica Bay. The wall is part of the Jamaica Bay Unit of the Gateway National Recreation Area.

The purpose of the underwater inspection was to investigate the cause of the reoccurring sinkholes on the landward side of the seawall, document the condition of the seawall and recommend repairs based on analysis of the existing conditions, if necessary. The inspection was visual for all accessible elements of the seawall to the mudline. No testing was performed. The inspection was performed under the supervision of

Bryan J. Juncosa, P.E., and three (3) of his staff over 7 days October 13, 14, 15, 21, 22, 23 & November 3, 2014. The locations and extent of defects was documented. Digital photographs were taken of typical conditions and major defects. A plan and section sketch was prepared depicting the configuration of the seawall. The previous report was reviewed prior to the inspection.

This report includes a summary of findings, conclusions and recommendations, plan and section views, soundings, condition tables, and photographs. Refer to the condition tables and photographs for further information.

SUMMARY OF FINDINGS

The length of the underwater inspection was 4,850 feet of the seawall. The seawall was stationed from the west starting at 0+00 heading east to 48+50.

The wall is constructed of reinforced concrete founded on steel sheeting. There is vertical timber 3” x 12” tongue and groove sheeting with a top 6” x 10” horizontal wale on the bay side that begins 5.2’ below the top of the concrete wall. The hardware connecting the timber sheeting to the wall was in poor condition with heavy corrosion.

The timber sheeting was in poor condition with many loose, missing and rotted boards with up to 2” penetration. There was 27,162 LF of vertical planking deteriorated and missing. The timber sheeting obstructed the inspection of the bottom portion of the concrete wall; however, due to the poor condition and missing and deteriorated boards the concrete was exposed in many places allowing it to be subject to corrosion. The concrete had moderate scaling throughout the tidal zone. There were a total 427 SF spalls along the face of the wall and at many of the vertical joints.

Below the concrete portion of the wall in front of the steel sheeting and behind the timber sheeting there is a voided area. This void was first detected at station 0+70 and continued the length of the wall to station

48+50. The void varied in height from 2’ to 5’ high and was up to 2.5’ deep behind the timber sheeting.

The presence of the void in some areas along the wall could not be determined because the vertical timber sheeting exists to the mudline. The total volume of the void is estimated to be a total of 1,555 CY.

The steel sheeting at the back of the void had several holes from deterioration. The holes were up to 1 SF in size for a total of 9 SF. These holes were exposing fill and in some areas the fill washed out causing sinkholes behind on the landward side of the wall. The total volume of sinkhole behind the seawall is estimated at 206 CY from the ground elevation.

Refer to the following tables and photos for additional information.

-2-

-3-

CONDITION TABLES

Project:

Location:

Station

LF of Missing and Deteriorated

Timber

0+00 - 0+49 35'

0+50 - 0+99 145'

1+00 - 1+49 160'

1+50 - 1+99 180'

2+00 - 2+49 90'

2+50 - 2+99 65'

SEAWALL CONDITION TABLE

Jacob Riis Park Seawall Underwater Inspection

Rockaway, Queens, NY

Description

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout. There is a

6"L x 4"H x 3"D spall along the cold joint 5' up from the mudline, located at sta 0+51. There is a 6'L x 12"H x 4'D area of undermining, located at sta 0+70.

There is a 2'L x 12"H x 6"D area of undermining, located at sta 0+90. There is a 50'L x 8"H band of scaling up to 2"D w/ exposed aggregate 4' above the mudline, starting at sta 0+90 heading east.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout. There is a

10'L x 18"W x 6"D corner edge spall along the joint starting at the top of seawall, located at sta 1+94. There is a 18"L x 9"H x 4"D spall w/ exposed rebar 6' above the mudline, located at sta 1+97.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout. There is a 4'L x

1'W x 6"D corner edge spall along the top of seawall, located at sta 2+10.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout. There is a

12"H x 2.5'D void w/ exposed metal sheeting starting at sta 2+55 heading east.

There is a 3.5'L x 4'H insipient spall along the joint, located at sta 2+80.

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Station

LF of Missing and Deteriorated

Timber

3+00 - 3+49 120'

3+50 - 3+99 70'

4+00 - 4+49 20'

4+50 - 4+99 15'

5+00 - 5+49 50'

5+50 - 5+99 20'

6+00 - 6+49 110'

SEAWALL CONDITION TABLE Cont'd

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 2+55 continues with a height ranging from 2' to 5' and ends at sta 3+30.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

There is a 2' to 5'H x 2.5'D void w/ exposed metal sheeting starting at the mudline, located at sta 3+60 heading east. There is a 3'L x 4'H insipient spall along the joint starting at top of the seawall, located at sta 3+66.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 3+60 continuous throughout.

Description

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 3+60 continuous throughout.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 3+60 continuous throughout. There is a 4'L x 18"W x 6"D corner spall along the joint w/ exposed rebar, located at sta 5+38.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 3+60 continuous throughout.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 3+60 continuous throughout. There is a 7'L x 18"W x 9"D corner spall along the joint w/ exposed rebar, located at sta 6+24.

kpowers Highlight kpowers Highlight kpowers Highlight kpowers Highlight kpowers Highlight kpowers Highlight and Deteriorated

Timber

6+50 - 6+99 65'

7+00 - 7+49 100'

7+50 - 7+99 60'

8+00 - 8+49 70'

8+50 - 8+99 60'

9+00 - 9+49 80'

SEAWALL CONDITION TABLE Cont'd

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 3+60 continuous throughout. There is a 5'L x 2'H x 3'W mudline build up at sta 6+80.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 3+60 continuous throughout. There is a 4'L x 1/4"W vertical crack w/ a 4'L x 4"W x 1/2"D corner edge spall starting at the top of the seawall, located at sta 9+20.

Description

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 3+60 continuous throughout. There is a 3'L x 4'H insipient spall along the joint starting at the top of the seawall, located at sta 7+11.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 3+60 continuous throughout.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 3+60 continuous throughout. There is a 2'L x 4'H insipient spall along the joint at the top of the seawall, located at sta 8+00

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 3+60 continuous throughout. There is a 5'L x 18"W x 9"D top corner spall along the joint, located at 8+53.

kpowers Highlight kpowers Highlight kpowers Highlight kpowers Highlight kpowers Highlight and Deteriorated

Timber

9+50 - 9+99 20'

10+00 - 10+49 60'

10+50 - 10+99 120'

11+00 - 11+49 70'

11+50 - 11+99 7'

12+00 - 12+49 60'

12+50 - 12+99 150'

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout. The void from sta 3+60 continuous throughout. There is a

2.5'L x 4'H insipient spall along the joint starting at the top of the seawall, located at sta 12+25.

SEAWALL CONDITION TABLE Cont'd

Description

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout. The void from sta 3+60 continuous throughout.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout. The void from sta 3+60 continuous throughout. There is a

18"L x 4'H x 2"D spall w/ exposed rebar starting at the top of the seawall, located at sta 10+75. There is a 6"L x 4'H insipient spall starting at the top of the seawall, located at sta 10+85.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout. The void from sta 3+60 continuous throughout. There is a 4'L x 2'W insipient spall starting at the top of the seawall, located at sta

11+40.

The vertical timber is in poor condition with up to 2" penetration. The concrete has 2'H moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout. The void from sta 3+60 continuous throughout.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout. The void from sta 3+60 continuous throughout. There is a 36" dia concrete outfall 7' up from the mudline w/ a 6'L x 6'H concrete headwall, located at sta 12+20. There is 1/4"D scaling on the face of the headwall.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout. The void from sta 3+60 continuous throughout. There is a

2.5'L x 3.5'H x 6"D spall w/ exposed rebar along the joint at the top of the seawall, located at sta 9+69.

kpowers Highlight kpowers Highlight kpowers Highlight kpowers Highlight kpowers Highlight kpowers Highlight and Deteriorated

Timber

13+00 - 13+49 600'

13+50 - 13+99 400'

14+00 - 14+49 600'

14+50 - 14+99 600'

15+00 - 15+49 600'

15+50 - 15+99 540'

SEAWALL CONDITION TABLE Cont'd

Description

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 3+60 continuous throughout. There is a 25'L horizontal cut in the vertical timber 2' up from the mudline, starting at sta 13+75 heading east.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 3+60 continuous throughout.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 3+60 continuous throughout. There is a 2'L x 1'H x 6"D top edge spall w/ exposed rebar, located at sta 14+83. There is a 6"L x 1'H hole 3' above the mudline in the exposed steel sheeting with a 1'L x 1'H x

2'D void behind the sheeting exposing fill, located at sta 14+90.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 3+60 continuous throughout. There is a 6"L x 6"H hole

3.5' above the mudline in the exposed steel sheeting with a 3'L x 1'H x 3'D void behind the sheeting exposing fill, located at sta 15+30.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 3+60 continuous throughout. There is a 6"L x 6"H hole

3.5' above the mudline in the exposed steel sheeting with a 3'L x 1'H x 3'D void behind the sheeting exposing fill, located at sta 15+50. There is a 1'L x

4'H x 2"D corner spall along the joint starting at the top of the seawall, located at sta 15+70. There is a 3'L x 4'H insipient spall located 4' below the top of seawall, at sta 15+70.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 3+60 continuous throughout.

kpowers Highlight kpowers Highlight kpowers Highlight kpowers Highlight kpowers Highlight kpowers Highlight kpowers Highlight kpowers Highlight and Deteriorated

Timber

16+00 - 16+49 300'

16+50 - 16+99 420'

17+00 - 17+49 180'

17+50 - 17+99 360'

18+00 - 18+49 420'

18+50 - 18+99 120'

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 18+25 continues throughout. There is a 18"L x 18"H x

2"D spall w/ exposed rebar starting 2' below the top of the seawall, located at sta 18+55. There is a 3'L x 4'H insipient spall starting at the top of the seawall, located at sta 18+85.

SEAWALL CONDITION TABLE Cont'd

Description

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 3+60 continuous throughout. There is a 18" dia concrete outfall 10' above the mudline, with a 4'L x 4'H concrete headwall. There is

2"D scaling on the face of the headwall.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 3+60 continuous throughout. There is a 2.5'L x 4'H x 6"D corner spall along the joint w/ exposed rebar starting at the top of the seawall, located at sta 16+55.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 3+60 continuous throughout. There is a 4'L x 6"H insipient spall along the joint starting at the top of the seawall, located at sta

17+15. There is a 4'L x 4'H x 6"D spall along the joint w/ exposed rebar starting at the top of the seawall, located at sta 17+44.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 3+60 continuous throughout.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 3+60 ends at sta 18+10. There is a 2' to 5'H x 2'D void with exposed steel sheeting starting at the mudline, located at sta 18+25 heading east. There is 3'L x 4'H x 4"D spall along the joint w/ exposed rebar starting at the top of the seawall, located at sta 18+30.

kpowers Highlight kpowers Highlight kpowers Highlight kpowers Highlight kpowers Highlight and Deteriorated

Timber

19+00 - 19+49 120'

19+50 - 19+99 420'

20+00 - 20+49 120'

20+50 - 20+99 110'

21+00 - 21+49 600'

21+50 - 21+99 600'

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 18+25 continues throughout.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 18+25 continues throughout.

SEAWALL CONDITION TABLE Cont'd

Description

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 18+25 continues throughout. There is a 4'L x 4'H insipient spall along the joint starting at the top of the seawall, located at sta 19+20.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 18+25 continues throughout. There is a 18"L x 2'H x 2"D spall w/ exposed rebar starting at the top of the seawall, located at sta 19+78.

There is a 12" dia concrete outfall 10' above the mudline, with a 4'L x 4'W concrete headwall, located at sta 19+90. There is 1"D scaling on the face of the headwall.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 18+25 continues throughout. There is a 3'L x 4'H x 3"D spall w/ exposed rebar along the joint starting at the top of the seawall, located at sta 20+00.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 18+25 continues throughout. There is a 8"L x 4'H x 3"D spall along the joint starting at the top of the seawall, located at sta 20+87.

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LF of Missing and

Deteriorated

Timber

22+00 - 22+49 70'

22+50 - 22+99 50'

23+00 - 23+49 600'

23+50 - 23+99 600'

24+00 - 24+49 600'

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 18+25 continues throughout. There is a 3'L x 2'W x 18"H mudline buildup, located at sta 24+10. There is a 15'L x 4'W x 2'H mudline buildup, located at sta 24+35. There is a 4'L x 4'W x 9"D spall along the joint w/ exposed rebar starting at the top of the seawall, located at sta

24+30.

SEAWALL CONDITION TABLE Cont'd

Description

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 18+25 continues throughout. there is a 18" dia concrete outfall 11' above the mudline with a 3.5'L x 4'H concrete headwall, located at sta 22+30. There is light scaling on the face of the headwall.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 18+25 continues throughout. There is a 6'L x 6'H x 12"D spall w/ exposed rebar 3' above the mudline, located at sta 22+50. There is a

3'L x 4'H insipient spall starting at the top of the seawall, located at sta

22+59. There is a 30" dia outfall 9.5' above the mudline, with a 4.5'L x 6'H concrete headwall, located at sta 22+75.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 18+25 continues throughout.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 18+25 continues throughout. There is a 4'L x 2.5'W x 2'H mudline buildup, located at sta 23+50. There is a 20'L x 18"W x 6"D spall w/ exposed rebar on top of the seawall, located at sta 23+65.

kpowers Highlight kpowers Highlight kpowers Highlight kpowers Highlight and Deteriorated

Timber

24+50 - 24+99 600'

25+00 - 25+49 150'

25+50 - 25+99 180'

26+00 - 26+49 150'

26+50 - 26+99 20'

27+00 - 27+49 80'

27+50 - 27+99 140'

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 18+25 continues throughout. There is a 4'L x 3'W x 18"H mudline buildup, located at sta 27+10. There is a 30'L x 6"W x 4"D top edge spall with exposed rebar, located at sta 27+20. There is a 12" dia outfall pipe with a 3.5'L x 4'H concrete headwall, located at sta 27+40. The concrete headwall has up to 3"D scaling throughout.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 18+25 continues throughout. There is a 6"L x 4"H hole in the steel sheeting 5' above the mudline, with a 2'L x 1'H x 3'D void behind the sheeting exposing fill, located at sta 27+55.

SEAWALL CONDITION TABLE Cont'd

Description

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 18+25 continues throughout. There is a 9'L x 4'W x 18"H mudline buildup, located at sta 25+00.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 18+25 continues throughout.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 18+25 continues throughout.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 18+25 continues throughout.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 18+25 continues throughout.

kpowers Highlight kpowers Highlight kpowers Highlight kpowers Highlight kpowers Highlight kpowers Highlight kpowers Highlight and

Deteriorated

Timber

28+00 - 28+49 40'

28+50 - 28+99 40'

29+00 - 29+49 200'

29+50 - 29+99 60'

30+00 - 30+49 60'

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 18+25 stops at sta 30+40. There is a 4'L x 2'W insipient spall starting at the top of the seawall, located at sta 30+33. There is a 2' to

5'H x 2'D void with exposed steel sheeting starting at the mudline, located at sta 30+50 heading east.

SEAWALL CONDITION TABLE Cont'd

Description

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 18+25 continues throughout.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 18+25 continues throughout. There is a 4'L x 2'W x 1'H mudline buildup, located at sta 28+80.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 18+25 continues throughout. There is a 20'L x 18"W x 6"D top edge spall w/ exposed rebar, located at sta 19+18. There is a 6"L x 7"H hole in the sheeting 6' above the mudline, w/ a 3'L x 1'H x 2'D void behind the sheeting exposing fill, located at sta 29+40.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 18+25 continues throughout. There is a 6"L x 6"H hole in the steel sheeting 6' above the mudline, w/ a 3'L x 1'H x 2'D void behind the sheeting exposing fill, located at sta 29+50. There is a 12"dia outfall 12' above the mudline w/ a 3.5'L w 4'H concrete headwall. There is a 2.5'L x 2'W x 8"D spall along the joint exposing rebar starting at the top of the seawall, located at sta 29+50.

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Timber

30+50 - 30+99 120'

31+00 - 31+49 180'

31+50 - 31+99 180'

32+00 - 32+49 540'

32+50 - 32+99 600'

33+00 - 33+49 240'

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 30+50 continues throughout. There is a 6"L x 4"H hole in the steel sheeting 4.5' above the mudline w/ a 1'W x 6"H x 1'D void behind the sheeting exposing fill, located at sta 32+70. There is a 8"L x 18"H hole in the steel sheeting 4' above the mudline w/ a 3'W x 1'H x 2.5'D void behind the sheeting exposing fill, located at sta 32+75.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 30+50 continues throughout.

SEAWALL CONDITION TABLE Cont'd

Description

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 30+50 continues throughout.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 30+50 continues throughout. There is a 3'L x 2.5'H x 4"D spall along the joint starting at the top of the seawall, located at sta 31+20.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 30+50 continues throughout. There is a 10'L x 8"W x 6"D top edge spall w/ exposed rebar, located at sta 31+50. There is a 5'L x 2.5'H x 3"D spall starting at the top of the seawall, located at sta 31+62.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 30+50 continues throughout.

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Deteriorated

Timber

33+50 - 33+99 600'

34+00 - 34+49 600'

34+50 - 34+99 600'

35+00 - 35+49 600'

35+50 - 35+99 600'

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 30+50 continues throughout. There is a 8'L x 3'W x 18"H mudline buildup, located at sta 35+50.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 30+50 continues throughout. There is a 7"L x 5"H hole in the steel sheeting 6' above the mudline w/ a 1'L x 2'H x 1'D void behind the sheeting exposing fill, located at sta 33+70. There is a 7"L x 8"H hole in the steel sheeting 4.5' above the mudline w/ a 3'L x 1'H x 1.5'D void behind the sheeting exposing fill, located at sta 33+80. There is a 7"L x 4"H hole in the steel sheeting 4.5' above the mudline w/ a 2'L x 8"H x 1.5'D void behind the sheeting exposing fill, located at sta 33+85. There is a 8"L x 1'H hole in the steel sheeting 4.5' above the mudline exposing fill, located at sta 33+90.

SEAWALL CONDITION TABLE Cont'd

Description

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 30+50 continues throughout. There is a 7'L x 4'W x 18"H mudline buildup, located at sta 34+00. There is a 6"L x 6"H hole in the steel sheeting exposing fill, located at sta 34+05.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 30+50 continues throughout. There is a 2'L x 18"W x 9"D spall along the joint starting at the top of the seawall, located at sta 34+75.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 30+50 continues throughout. There is a 9'L x 4'W x 18"H mudline buildup, located at sta 35+00.

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Deteriorated

Timber

36+00 - 36+49 600'

36+50 - 36+99 540'

37+00 - 37+49 600'

37+50 - 37+99 540'

38+00 - 38+49 360'

38+50 - 38+99 360'

39+00 - 39+49 60'

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 30+50 continues throughout.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 30+50 continues throughout. There is a 18" dia outfall 5' above the mudline.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 30+50 continues throughout.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 30+50 continues throughout. There is a 12'H x 5'L x 6"D spall with exposed rebar starting at the top of the seawall, located at sta

36+37. There is a 9'L x 6'W x 3'H mudline buildup, located at sta 36+40.

SEAWALL CONDITION TABLE Cont'd

Description

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 30+50 continues throughout. There is a 10'L x 3'W x 2'H mudline buildup, located at sta 36+65.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 30+50 continues throughout.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 30+50 continues throughout.

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Deteriorated

Timber

39+50 - 39+99 60'

40+00 - 40+49 600'

40+50 - 40+99 570'

41+00 - 41+49 450'

41+50 - 41+99 600'

42+00 - 42+49 600'

42+50 - 42+99 600'

43+00 - 43+49 600'

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout. The void from sta 30+50 continues throughout.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout. The void from sta 30+50 continues throughout.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout. The void from sta 30+50 continues throughout.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout. The void from sta 30+50 stops at sta 43+50.

SEAWALL CONDITION TABLE Cont'd

Description

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout. The void from sta 30+50 continues throughout.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout. The void from sta 30+50 continues throughout.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout. The void from sta 30+50 continues throughout.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout. The void from sta 30+50 continues throughout. There is an 18" dia outfall 5' above the mudline, w/ a 4'L x 6'H concrete headwall, located at sta 41+25. There is light scaling on the face of the headwall.

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Deteriorated

Timber

43+50 - 43+99 210'

44+00 - 44+49 390'

44+50 - 44+99 570'

45+00 - 45+49 570'

45+50 - 45+99 360'

46+00 - 46+49 60'

46+50 - 46+99 60'

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 30+50 continues throughout.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 30+50 continues throughout.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 30+50 continues throughout.

SEAWALL CONDITION TABLE Cont'd

Description

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 30+50 continues throughout. There is a 24" dia outfall 5' above the mudline w/ a 4'L x 6'H concrete headwall, located at sta 43+90. The concrete headwall has light scaling throughout.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 30+50 continues throughout. There is a 48" dia outfall 6' above the mudline, located at sta 44+10. There is a 24" dia outfall 6' above the mudline, located at sta 44+30. There is up to 4"W x 2"D spall w/ exposed rebar around the exterior of the pipe.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 30+50 continues throughout.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout.

The void from sta 30+50 continues throughout.

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Deteriorated

Timber

47+00 - 47+49 60'

47+50 - 47+99 120'

48+00 - 48+50 10'

Description

SEAWALL CONDITION TABLE Cont'd

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout. The void from sta 30+50 continues throughout.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout. The void from sta 30+50 continues throughout.

The vertical timber is in poor condition with up to 2" penetration. The concrete has a 2'H band of moderate scaling in the tidal zone. There are fine horizontal and vertical cracks with efflorescence and rust stains throughout. The void from sta 30+50 continues throughout.

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DRAWINGS

-20-

-40-

SOUNDING DATA

Date: 10/13/2014

Station Clear Dimension Water Depth

0+00 0' 0'

1+00 13' 6'

2+00 13'9" 6'9"

3+00 17' 9'11"

4+00 16'9" 9'8"

5+00 16'9" 9'7"

6+00 17' 9'10"

7+00 17'2" 9'11"

8+00 17'3" 9'11"

9+00 17'4" 10'

10+00 17'5" 10'1"

11+00 17'4" 10'

12+00 16'8" 9'4"

13+00 17'4" 9'11"

14+00 17'11" 10'6"

15+00 17'2" 6'7"

16+00 17'9" 7'2"

17+00 17'10" 7'3"

18+00 17'7" 7'

19+00 17'5" 6'11"

SOUNDINGS AND MUDLINE DESCRIPTION

Note: Clear dimension= top of concrete wall to mudline.

Jacob Riis Park Seawall Underwater Inspection

Rockaway, Queens, NY

Sand and silt, 2" penetration

Mudline Description

8" to 2' diameter stone riprap

Sand, silt and shells, 0" penetration

Sand, silt and shells, 6" penetration

Sand, silt and shells, 6" penetration

Sand and shells, 6" penetration

Sand and shells, 2" penetration

Sand and shells, 2" penetration

Sand and shells, 2" penetration

Sand and shells, 2" penetration

Sand and shells, 2" penetration

Sand, silt and shells, up to 3" penetration

Sand and shells, 0" penetration

Sand and silt, 2" penetration

Sand and silt, 2" penetration

Sand and silt, 2" penetration

Sand and silt, up to 2" penetration

Sand and silt, up to 2" penetration

Sand and silt, up to 2" penetration

Sand and silt, up to 4" penetration

Date: 10/22/2014

Station Clear Dimension Water Depth

20+00 17'3" 6'9"

21+00 17'2" 6'9"

22+00 16'11" 6'6"

23+00 17'7" 7'2"

24+00 17'5" 7'

25+00 16'7" 6'2"

26+00 17'5" 7'1"

27+00 18' 10'2"

28+00 18' 10'2"

29+00 18' 10'2"

30+00 18' 10'6"

31+00 19' 12'

32+00 19'6" 12'6"

33+00 19'6" 12'6"

34+00 20' 13'

35+00 18'9" 11'9"

36+00 18'5" 11'5"

37+00 19' 12'6"

38+00 19' 10'7"

39+00 20' 8'6"

Sand and shells, 7" penetration

Sand and shells, 4" penetration

Sand and shells, 6" penetration

Sand and shells, 2" penetration

Sand and shells, 2" penetration

Sand and shells, 2" penetration

Sand and shells, 6" penetration

Sand and shells, 2" penetration

Sand and shells, 2" penetration

SOUNDINGS AND MUDLINE DESCRIPTION

Note: Clear dimension= top of concrete wall to mudline.

Jacob Riis Park Seawall Underwater Inspection

Rockaway, Queens, NY

Sand and shells, 1" penetration

Mudline Description

Sand and stones, 2" penetration

San and shells, 2" penetration

San and shells, 2" penetration

San and shells, 2" penetration

San and shells, 2" penetration

Sand and shells, 2" penetration

Sand and shells, 1" penetration

Sand and shells, 4" penetration

Sand and shells, 1" penetration

Sand and shells, 1" penetration

Date: 10/23/2014

Station Clear Dimension Water Depth

40+00 20' 8'6"

41+00 20' 8'6"

42+00 20' 8'6"

43+00 20' 8'6"

44+00 20' 8'6"

45+00 20' 8'6"

46+00 20' 8'6"

47+00 20' 8'6"

48+00 20' 8'6"

48+75 20' 8'6"

Sand and shells, 2" penetration

Sand and shells, 4" penetration

Sand and shells, 4" penetration

Sand and shells, 3" penetration

Sand and shells, 4" penetration

Sand and shells, 2" penetration

Sand and shells, 2" penetration

Sand and shells, 2" penetration

Sand and shells, 2" penetration

Sand and shells, 3" penetration

SOUNDINGS AND MUDLINE DESCRIPTION

Note: Clear dimension= top of concrete wall to mudline.

Jacob Riis Park Seawall Underwater Inspection

Rockaway, Queens, NY

Mudline Description

CONCLUSIONS & RECOMENDATIONS

The overall condition of the seawall is poor due to the voids below the concrete wall in front of the steel sheeting, holes in the steel sheeting with voids behind, sinkholes on the landward side of the wall, spalls in the concrete wall, and severely deteriorated, loose and missing timber sheeting boards.

We recommend the following course of action.

1. Repair spalls in concrete wall with epoxy concrete 427 SF.

2. Repair holes in steel sheeting 9 SF.

3. Fill voids behind steel sheeting with concrete 2.2 CY.

4. Fill voids behind vertical timber sheeting with concrete 1,555 CY.

5. Replace missing and deteriorated 3” x 12” tongue and groove timber sheeting 27,162 LF.

6. Fill sinkholes on the landward side of the seawall with select structural fill 206 CY.

-44-

PHOTOGRAPHS

-45-

-46-

PHOTO 1 - Station 0+50, diver in action, looking down.

PHOTO 2 - Station 0+90, missing and deter iorated 3” x 12” ver tical timber planks (typ), Nor th looking Southeast.

-47-

PHOTO 3 - Station 1+15, 2’H band of moderate scaling in the tidal zone, Nor th looking Southwest.

PHOTO 4 - Station 1+50, heavily corroded and missing timber sheeting hardware (typ), North looking South.

PHOTO 6 - Station 14+90, 6"L x 1'H hole 3' above the mudline in the exposed steel sheeting with a 1'L x 1'H x 2'D void behind the sheeting exposing fill. North looking South.

PHOTO 5 - Station 7+40, 2’ to 5’H x 2.5’D void star ting at the mudline (typ), Nor th looking South.

-48-

-49-

PHOTO 8 - Station 20+00, deteriorated timber sheeting with up to 2” penetration (typ).

Elevation view, East looking West.

PHOTO 7 - Station 19+90, 12" dia concrete outfall 10' above the mudline, with a 4'L x 4'W concrete headwall. There is up to 1"D scaling on the face of the headwall. North looking South.