Jacob_Riis_Parking_Lot_Engineering_Study_Report_7-21-2014_low_res.pdf

NATIONAL PARK SERVICE - NORTHEAST REGION

JACOb RIIS PARK PARKING LOT ENGINEERING STudy GATEWAy NATIONAL RECREATION AREA JAMACIA bAy uNIT

GATE 195485

GSA CONTRACT NO. GS-10F-0286T

TASK ORdER NO. P14Pb00095

Final Report

Vanasse Hangen Brustlin, Inc.

Submitted To National Park Service

Submitted by

July 21, 2014

Table of Contents

Executive Summary

Background

Previous Projects and Studies

Sinkhole Repair Halcrow Report Ground Penetrating Radar Post Sandy Surface Repair

Evaluation of Existing Conditions

Topographic Survey Storm Drain Video Inspection Hydraulic Analysis Seawall Inspection Pavement Surface Multi-modal Traffic Circulation Accessibility Sustainability

Recommendations and Cost Estimates

Storm Drainage Parking Lot Sinkhole Pavement Surface Seawall Multi Use Trail Beach Channel Drive Storm Drainage Lines Cost Summary

Appendix A Location M ap

Appendix B Study Area M ap

Appendix C Storm Drain Video Inspection Report

Appendix D Drainage Area M ap

Appendix E Detailed Seawall Condition M apping

Appendix F Photo Documentation

Appendix G Cost Estimates

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Table of Contents

Executive Summary

The area of this Engineering Study includes the parking lot serving the Jacob Riis Park within the Jamaica Bay Unit of the Gateway National Recreation Area as well as the seawall facing Jamaica Bay to the north of the parking lot and Beach Channel Drive.

The purpose of this project is to conduct field investigations to identify existing conditions of the storm drainage system, pavement surface, and seawall and develop recommended repairs and estimated costs based on an engineering analysis of the existing conditions.

The evaluation of existing conditions included:

• Conducting a topographic survey of the parking lot and surrounding areas,

• Conducting a close circuit TV inspection of the storm drain lines within the parking lot area as well as the lines leading to Jamaica Bay,

• An inspection of the seawall facing Jamaica Bay to the north of the parking lot, including a walking inspection of the top of the seawall as well as an inspection of the face of the seawall from the water, and

• A visual inspection of the parking lot pavement surface

Recommendations are made for the rehabilitation of five features including:

• Storm Drainage

• Sinkhole in Parking Lot

• Pavement Surface

• Seawall

• Multi Use Path

In addition, recommendations are made concerning the investigation and potential rehabilitation of storm drainage lines serving beach Channel Drive. Total estimated costs associated with all rehabilitation needs are $12,087,349. Details of the evaluation, recommended rehabilitation, and estimated costs are included in the following report and appendices.

1 Executive Summary

Background

The area of this Engineering Study includes the parking lot serving the Jacob Riis Park within the Jamaica Bay Unit of the Gateway National Recreation Area as well as the seawall facing Jamaica Bay to the north of the parking lot and Beach Channel Drive.

Appendix A is a location map for the study and Appendix B is a map of the study area.

The Jacob Riis Park parking lot was inundated during Hurricane Sandy. The Park and the surrounding area sustained major damage during the storm. The parking lot served as a staging area for debris collection and removal in the months following the storm, which resulted in additional damage from associated heavy equipment.

The purpose of this project is to conduct field investigations to identify existing conditions of the storm drainage system, pavement surface, and seawall and develop recommended repairs and estimated costs based on an engineering analysis of the existing conditions.

1 Background

Previous Projects and Studies

Various studies and repairs have been performed in the parking lot and its vicinity since 2004. A summary of those studies and repairs is provided below.

Sinkhole Repair In August of 2004, in response to a sinkhole failure near a catch basin in the north central portion of the parking lot (referenced as catch basin #3 in this report), the FHWA investigated existing conditions and developed schematic plans for the repair of the sinkhole failure. The recommended repairs included excavating the sinkhole area, replacing a failed section of pipe, sealing and grouting connections between existing sections of pipe and between the pipe and the catch basin, wrapping the connections between the pipe and the catch basin with geotexti le, backfill ing the repair area with sand, placing 8’’ of aggregate base material, and finally placing a 6’’ concrete pavement. Subsequent to the schematic plans being developed, these repairs were completed.

Subsequent to the repairs being completed, the sinkhole reappeared in what appears to be the same location. The most likely reason for the second failure is infi ltration of sand into the storm drainage line due to a poor seal between sections of original pipe, a poor seal between the section of pipe that was replaced and the original pipe, a poor seal between the pipe and the catch basin, or failure of the geotextile to perform as intended.

Halcrow Report In December of 2010, Halcrow Engineers, P.C. was commissioned by the New York City Economic Development Commission to conduct a subsurface void detection survey on Beach Channel Drive in the vicinity of and to the east of the Jacob Riis Park parking lot. The report specifically investigated the condition of Beach Channel Drive in the two locations where the storm drain pipes from the Jacob Riis parking lot run under the road. While significant voids were detected to the east of the NPS property, the Halcrow report concluded that there was no pipe failure and no voids evident in the storm drain pipe locations.

2 Previous Projects and Studies

Ground Penetrating Radar In May of 2013, the Federal Highway Administration, through a Small Business Innovation Research project, conducted a void detection study of the Jacob Riis Park parking lot as well as Beach Channel Drive immediately north of the parking lot. In addition to the sinkhole in the north central area of the parking lot, the study identified two possible void locations slightly south of the sinkhole. The report recommended that these locations be monitored for any future signs of distress. In addition, the report noted a possible void location under Beach Channel Drive in the vicinity of the more easterly storm drainage outfall pipe from the parking lot. The report notes that the existence of a void in this location is not certain, as the ground penetrating radar signal in this location was impacted by a change in pavement structure in the same location. The Halcrow report also noted the change in pavement as a potential cause of the transverse crack in the pavement that can be observed in this location.

Post Sandy Surface Repair In the spring of 2014, the Army Corp of Engineers conducted an inspection of the pavement surface condition of the Jacob Riis Park parking lot. The intent of the inspection was to identify pavement distress caused by recent heavy equipment operations in the parking lot connected with clean up and recovery efforts after Hurricane Sandy in the vicinity of Jacob Riis Park. Subsequent to the inspection, plans were prepared and pavement surface repairs were performed including full or partial replacement of failed concrete slabs. These repairs are approximately 80 percent complete as of the writing of this report. Upon completion of these repairs, the large majority of significant surface distress w ill be repaired.

Pavement repair in process

3 Previous Projects and Studies

Evaluation of Existing Conditions

The evaluation of existing conditions w ithin the scope of this study included:

• Conducting a topographic survey of the parking lot and surrounding areas

• Conducting a close circuit TV inspection of the storm drain lines within the parking lot area as well as the lines leading to Jamaica Bay

• Conducting a hydraulic analysis of the existing storm drainage system serving the parking lot

• An inspection of the seawall facing Jamaica Bay to the north of the parking lot, including a walking inspection of the top of the seawall as well as an inspection of the face of the seawall from the water.

• A visual inspection of the parking lot pavement surface

• An evaluation of opportunities to improve multi-modal traffic flow, accessibility, and sustainability in conjunction w ith functional and structural improvements recommended for the parking lot and seawall areas.

A description of each of these inspections and evaluations follows.

Topographic Survey A VHB survey crew conducted a topographic survey of the study area on March 4 through March 12, 2014. The survey was conducted using Real Time Kinematic GPS survey techniques and also conventional total station techniques and equipment. In addition to topography, the location and elevation of drainage features, curbing, sinkholes near the seawall, and the seawall itself were recorded and mapped. A ll data was referenced to the NAVD88 vertical datum and the NAD83 Horizontal Datum. CAD files were developed and delivered to the NPS on the Hurricane Sandy SharePoint site using NPS standard symbology.

Storm Drain Video Inspection Savin Engineers, P.C. conducted a closed circuit TV inspection of the storm drainage system within the Jacob Riis Park parking lot on April 8th and 9th, 2014. The inspection was conducted to document physical defects such as collapsed or broken pipes, offset joints, corrosion, and similar defects. In addition, maintenance needs such as

4 Evaluation of Existing Conditions debris accumulation, root intrusion, and grease accumulation were recorded. A report titled ‘‘Video Inspection of Storm Drains’’ dated April 2014 included as Appendix C of this report summarizes the physical condition of the existing storm drains. The report concludes that the ‘‘drains that were inspected are in relatively poor condition and require significant rehabilitation or maintenance’’. The follow ing summary table is included in the report:

The report identifies two areas with significant structural deficiencies. The first is identified as the 377 linear feet of 30’’ concrete pipe connecting catch basin #10 (the northeastern most catch basin) to the outfall. The second area with significant cracking and structural deficiencies is identified as the 280 linear feet between manhole 4 and catch basin 9. This area is located in the northeastern portion of the parking lot.

Additionally, there is a sinkhole around catch basin 3, located in the northern portion of the parking area. The area impacted by the sinkhole is approximately 5,000 sf. It should be noted that the initial length of pipe in each direction is corrugated metal which then transitions to concrete pipe.

5 Evaluation of Existing Conditions

Sinkhole near Catch Basin #3

Hydraulic Analysis The storm water surface drainage for the approximate 62.5 acre parking lot drains to six catch basins located in the main parking field. Additional basins are located at the Rockaway Beach Boulevard entrance.

For drainage analysis purposes the site may be divided into seven drainage areas varying in size from 2 acres at the entrance to 7 acres within the main parking area.

The largest area w ithin the parking field is over 13 acres. Runoff from each drainage area is collected by one catch basin. The catch basins are connected in series by pipes which discharge to Jamaica Bay in two locations. Appendix D contains a map of the drainage areas used for analysis.

Typically, the contributing area to a single catch basin is limited to half an acre based on the inlet capacity of the catch basin. The existing catch basins within the parking field are currently collecting runoff from much larger areas. However, NPS staff observations over several years have indicated that the parking lot drains without significant issue.

A preliminary hydraulic analysis of the site for a 10 year storm confirms that the contributing runoff to each catch basin exceeds the theoretical hydraulic capacity of the pipes which are conveying flow to the Bay. Calculation would indicate that the contributing drainage areas are producing flows ranging from 9 cubic feet per second (cfs) to 40 cfs to each catch basin. The contributing flows are combined w ithin the pipe system as runoff is directed towards the two ultimate discharge locations. As a result, the ultimate flows at the discharge points are estimated to increase to

6 Evaluation of Existing Conditions approximately 86 to 115 cfs. The maximum capacity of the pipes conveying this flow is approximately 20 cfs. The Rational Method was used to determine the approximate contributing flows and Manning’s Equation was used to determine the capacity of the pipes. Due to the condition of the surface of the parking lot, it is likely that runoff infi ltrates through cracks and other surface imperfections prior to being collected by the catch basins, thus explaining the difference between predicted and observed performance.

Seawall Inspection

Introduction and Background

VHB performed a condition assessment inspection on February 26 and 27, 2014 of the seawall along Jamaica Bay associated the Jacob RIIS Park parking lot. The purpose of the inspection was to identify and quantify structural and functional defects along the entire seawall and drain l ine outlets. The seawall inspection consisted of a landside inspection of the top of the seawall and a waterside inspection of the face of the seawall. The inspection was performed by Kevin Powers, P.E. and A lex Deduck from VHB and supported by the National Park Service Park Police through the use of their patrol boat for the water side inspection.

The landside inspection consisted of walking the entire length of the seawall and visually looking for disturbances behind the seawall that would indicate loss of fill through the seawall via the drainage system that penetrate the wall or other types of wall deterioration. The waterside inspection, conducted by boat, consisted of recording observations of the condition of the seawall including damaged or missing timber fendering and damaged railing, intermittent soundings of concrete to determine concrete integrity, and recording conditions at each of the drain pipe outlets. Due to high w inds and rough seas in Jamaica Bay, the afternoon waterside inspection was limited to distance observations and no hands on (concrete sounding) inspection was performed.

Detailed mapping of the observed seawall and sinkhole conditions is provided in Appendix E. Photos of the observed conditions are included in Appendix F.

Observations

Landside (Walking) Inspection

The seawall was stationed from west to east starting at the beginning of the concrete seawall where it transitions from a riprap embankment east of the Gil Hodges Memorial Bridge.

7 Evaluation of Existing Conditions

While stationing the wall, it was observed that the wall timber facing and fendering.

The timber facing consists of 3’’x12’’ tongue and groove vertical boards with a 6’’x10’’ horizontal wale at the top edge of the timber facing. The timbers are anchored back to the seawall with 1’’ diameter bolts spaced approximately every 4 feet. The top of the timber facing and wale start at 5.2 feet below the top of the seawall and extended below the water line. A t various locations, the timber facing has deteriorated at or about the waterline, the wale is missing, or the timber facing and wale are missing.

The wall height was measured from Station 1+00 to Station 27+00 using a weighted tape measure. From station 0+00 to station 2+00 riprap from the adjacent work fi lled in front of the wall and no height measurements were taken. Starting at station 3+00, the wall height varied between 17.6 feet and 18.7 feet.

Beyond Station 27+00, wall heights were not measured.

Beyond Station 36+00, landside observations were not performed due presence of a construction staging area for work being performed in the area.

Sinkholes behind the wall:

• Station 7+40 to 7+50: A sinkhole was observed from (Photo 1). These stations correspond with a drainage structure located at Station 7+50.

• Station 11+40 to 11+80: A sinkhole that appeared to be recently filled was observed (Photo 2). A 24-inch diameter drainage structure is located nearby at Station 12+20.

• Stations 14+75: Small sinkhole was observed.

• Station 18+50 to 19+50: A sinkhole that appeared to be recently filled was observed, (Photo 3). A 12-inch diameter drainage structure is located close by at Station 19+80.

• Station 22+50 to 25+00: A series of small sinkholes, 20 to 30-inches w ide were observed (Photo 4). A 30-inch diameter drainage structure is located nearby at Station 22+50.

• Station 27+50 to 27+75: A sinkhole was observed (Photo 5). A 12-inch diameter drainage structure is located nearby at Station 27+20.

• Station 28+75: A sinkhole was observed (Photo 6).

• Station 29+00 to 29+75: A large sinkhole was observed (Photo 7).

• Station 30+70: A sinkhole was observed (Photo 8).

• Station 31+75: A sinkhole was observed (Photo 9).

• Station 32+60: A sinkhole was observed (Photo 10). An 18-inch diameter drainage structure is located nearby at Station 32+20.

• Station 33+50: A sinkhole was observed (Photo 11).

8 Evaluation of Existing Conditions

• Station 34+80: A sinkhole was observed (Photo 12). An 18-inch diameter drainage structure is located nearby at Station 34+70.

• Station 35+60: A sinkhole was observed (Photo 13).

Seawall Railing:

• Stations 18+60 and 18+80: The rail ing is missing (Photo 14).

• Station 21+00: The railing is displaced.

• Station 25+00: The railing is missing (Photo 15).

• Station 26+50: The railing is missing balusters (Photo 16).

• Station 28+75 to 29+50: Top rail of railing is missing (Photo 6).

• Various railing posts between Stations 0+00 to 27+00 were loose due to cracking in the concrete at the top of the wall or loss of mortar around individual posts at the wall interface.

Waterside (Boat) Inspection

Waterside inspection was performed with the assistance of the National Park Service Park Police patrol boat docked at the Jacob RIIS Landing Marina. Two trips were taken to the site on February 27th to make observations and inspect the seawall. The first trip taken in the morning trip covered Stations 0+00 to 27+00 and began at approximately 8:30am at a mid-tide and fall ing.

The second trip taken in the afternoon covered Stations 27+00 to end of the wall, approximately Station 48+50. Due to high winds and rough seas the afternoon inspection was limited to several ‘‘ride by’’ observations and no hands on (concrete sounding) was performed. The second trip in the afternoon began at approximately 12:45pm. Per NOAA tide records, on February 27th, 2014, low tide at the Beach Channel (bridge) in Jamaica Bay was at 12:39pm.

Morning Inspection:

• Station 7+50: An 18-inch diameter pipe penetrates the seawall at this location. The pipe has a 48-inch x 48-inch headwall that projects 8 inches from the face of the concrete wall. The bottom 12-inches of the headwall had exposed rebar (Photo 17). The headwall was sounded and found to be hollow sounding and in poor condition. The concrete of the wall above the timber facing was sounded and was found to be in good condition.

• Station 8+00: An area of the seawall above the timber wale has spalled concrete along the expansion joint in the wall (Photo 18). The timber facing has separated from the seawall (Photo 19) and the wall joint material is exposed and beginning to pull away from the wall.

9 Evaluation of Existing Conditions

• Station 8+90: Spalled concrete in an area 60-inch wide area with height varying between 30-inch and 20-inch from the top of the seawall. Horizontal crack 12-inches from the top of the wall that runs approximately 12-feet along length. The wall at this location was confirmed to be plumb.

• Station 10+80: An 18-inch wide section of the concrete seawall full height (5-feet) above of the timber facing has spalled and has rust stains, indicating corroded reinforcement (Photo 20). Timber facing deterioration (Photos 21 and 22), looking east and west respectively.

• Station 11+45: Horizontal crack along the top of the seawall at the rail ing anchorage (Photo 23).

• Station 12+20: 36-inch diameter drainage outfall pipe with a 72-inch x 72-inch headwall (Photo 24). The headwall concrete above the top of the pipe is severely deteriorated.

• Station 12+00 to 13+00: Horizontal crack 12-inches from the top of the seawall at the railing anchorage (Photo 25).

• Station 16+20: 18-inch diameter clay pipe with a 52-inch x 49-inch headwall.

The headwall was sounded and found to be in fair condition with some minor concrete spalling along the edges (Photos 26).

• Station 17+00: Areas efflorescent was observed above of the timber facing on the seawall. Timber facing deterioration (Photos 27 and 28), looking east and west respectively.

• Station 17+50: deteriorated joint in seawall including spalled concrete, (Photo 29).

• Station 18+25: deteriorated joint in seawall (Photo 30)

• Station 19+80: A 12-inch diameter pipe with a 48-inch x 52-inch headwall (Photo 31).

• Station 19+70 to 20+00: concrete seawall full height (5-feet) above of the timber facing has large spalls rust staining, indicating corroded reinforcement, and when sounded was found to be hollow, indicating delamination of the concrete and future spalls. Horizontal crack 12-inches from the top of the seawall at the railing anchorage (Photos 32, 33, and 34).

• Station 22+30: 16-inch diameter clay pipe with a 53-inch x 47-inch headwall, (Photos 35). The headwall around pipe was sounded and was found to be in good condition with minor scaling along the lower edge. Timber facing deterioration (Photos 36 and 37), looking east and west respectively.

• Station 22+70: 30-inch diameter pipe with a 53-inch x 75-inch headwall. The headwall was sounded and found to be good condition with minor scaling along the lower edge (Photo 38). Several of the vertical timbers are missing (Photo 39) and the condition of the concrete behind them was observed to be on good condition.

10 Evaluation of Existing Conditions

• Station 24+30: 36-inch w ide section of the concrete seawall full height (5-feet) above of the timber facing spalled and w ith exposed reinforcement (Photos 40).

• Station 27+20: 12-inch diameter pipe with a 50-inch x 48-inch headwall, (Photos 41). The headwall around pipe was sounded and was found to be in fair condition w ith spalls on all edges and scaling along the lower edge.

Afternoon Inspection/Observations

• Station 29+40 to 37+40: Majority of the timber facing missing or heavily deteriorated (Photo 42, Photo 43, Photo 46, Photo 47, and Photo 48). Station 37+40 is where the railing type changes.

• Station 29+70: 12-inch diameter pipe with estimated 48-inch x 48-inch headwall (Photo 44). Headwall appears to have only scaling on the lower half.

• Station 32+30: 18-inch diameter pipe with estimated 60-inch x 54-inch headwall (Photo 45). Headwall appears to have scaling on the lower half, and few spalls on the lower edge.

• Station 34+70: 16-inch diameter pipe with estimated 66-inch x 66-inch headwall (Photo 46). Headwall appear to have only scaling on the lower half.

• Station 36+10: 48-inch w ide section at the seawall joint full height (5-feet) above of the timber facing spalled and w ith exposed reinforcement (Photo 47).

• Station 36+60: 18-inch diameter pipe with estimated 55-inch x 52-inch headwall (Photo 48). Headwall appears to have scaling on the lower half, and a significant spall on the lower east corner.

• Station 38+50: 16-inch diameter pipe, (Photo 49). Headwall size and condition could not be estimated. Headwall appears to be recessed into the wall.

• Station 39+70 to 40+80: Timber facing missing. Concrete appears to have some scaling.

• Station 41+00: 18-inch diameter pipe, (Photo 50). Headwall size and condition could not be estimated. Headwall appears to be recessed into the wall.

• Station 43+50 to 43+75: Outfall of three drainage pipes, 18-inch diameter, 48-inch diameter, and 24-inch diameter (Photo 51), west to east respectively.

The 48-diameter pipe has a trash rack over the opening. The timber facing around the 24-inch diameter and the 18-inch diameter completely missing.

• Station 45+00: 18-inch diameter pipe, (Photo 52). Headwall size could not be estimated, but appears to have heavy scaling on the exposed face. Headwall appears to be recessed into the wall.

11 Evaluation of Existing Conditions

• Station 46+50 (144th Street): Outfall of two drainage pipes, 18-inch diameter, 48-inch diameter, (Photo 53), west to east respectively. Headwall sizes and condition could not be estimated. Headwalls appears to be recessed into the wall.

• Station 48+30: 18-inch diameter pipe, (Photo 54). Headwall size and condition could not be estimated. Headwall appears to be recessed into the wall.

• Photos 55 to 57: Various location where timber facing has deteriorated completely. Marine growth and concrete scale on the face of the wall below the high tide line. Photo 57 shows a suspected horizontal crack in the wall.

The wall did not show any other signs of distress (tipping, bulging) at this location. The line may be a shadow within the marine growth.

Pavement Surface Prior to the current pavement surface restoration project, the pavement surface of the parking lot exhibited several distress types including broken slabs, deteriorated patch areas, joint damage, cracking, surface wear, and spall ing. The current pavement restoration project will correct the majority of the areas of broken slabs, deteriorated patch areas, and some of the other observed distress. The topographic survey shows that overall, the surface of the parking lot has not distorted significantly from planar surfaces that are properly graded toward the limited number of catch basins within the parking lot area (See photos 58 and 63 in Appendix F). An example of the broken concrete slabs that have now been repaired is shown in photo 64 in Appendix F. Other areas of spall ing and surface wear as shown in photos 59 and 60 have also been repaired. Finally, some areas of concrete curbing surrounding the grass median within the parking lot area need to be replaced (see photo 62).

Repaired pavement surface near parking lot entrance

12 Evaluation of Existing Conditions

In part due to the sinkholes described above along the top of the seawall, and in part due to deterioration over time, the surface of the multi-use trail that runs parallel to the top of the seawall is in very poor condition, and is impassible in certain locations.

Multi-modal Traffic Circulation Jacob Riis Park has been accessible by mass transit (bus service) for many years, at least in part due to the intended use of the Park as a recreation area for New York City residents. As such, Rockaway Beach Boulevard is designed to smoothly circulate traffic destined for the parking lot as well other traffic destined to drop off people at the front of the bathhouse. The traffic circle northeast of the bathhouse allows a continuous flow of this mix of traffic.

Bus service arriving at Jacob Riis Park

The bus service serving the Park connects to the New York City subway system. In addition, ferry service is provided to Riis Landing to the northwest of the Park. As the highlighted green lines in the image below show, access to the Park by bicyclists and pedestrians is provided via a network of trails, including the multi-use trail running parallel to and just south of the seawall. Bicycle storage accommodations are provided at the bathhouse.

13 Evaluation of Existing Conditions

As shown below, guidance signs w ithin the parking lot direct pedestrians to the intended pedestrian walking lanes. The striping that is being renewed as part of the current Corp of Engineers project has improved the definition of the pedestrian walkways.

14 Evaluation of Existing Conditions

Accessibility A 20 space parking lot designated for administrative and handicap accessible use only exists just to the east of the bath house, immediate adjacent to the bath house promenade. This lot provides accessibility to the promenade and adjacent facilities.

Additional parking spaces have been marked for handicap accessible parking in the southwest and southeast portion of the main parking lot. Access to the promenade and other facilities from the spaces in the southeastern portion of the lot requires the use of a staircase, which does not comply with current Federal accessibility standards. Access to the promenade and other facilities is provided from the spaces in the southwestern portion of the lot (shown below) by a sidewalk with multiple pedestrian accessibility ramps. If there is an observed demand for additional handicap accessible parking spaces, it would be prudent to consider providing additional spaces in the southwest portion of the lot.

Handicapped parking spaces in southwest portion of parking lot

Regarding the multi-use trail along the seawall, given the sinkholes observed along the seawall, many being in the vicinity of the multi-use trail, as well as the poor pavement condition of the trail, the trail is not currently accessible to all potential users.

15 Evaluation of Existing Conditions

Sustainability The parking lot has been inundated during multiple storms, including during Hurricane Sandy. FEMA has estimated the flood elevation during Sandy at 11 feet.

The elevation of the parking lot ranges from a low of 6.3 feet above mean sea level at the northeastern most catch basin and a high of 10.1 feet near the southwest corner of the lot.

Multiple flood events have not resulted in catastrophic failure to the parking lot or seawall; however, damage such as acceleration of the sinkholes at the top of the seawall has occurred. Raising the elevation of the parking lot is not economically feasible or desirable. Facilities designed to continue to survive inundation during intermittent flood events would seem to be most prudent. This would imply that continuing to maintain the existing hard surfaced lot will provide a more resilient surface than options involving removal of portions of the existing concrete.

16 Evaluation of Existing Conditions

Recommendations and Cost Estimates

The follow ing section identifies rehabil itation treatment options and estimated costs for five components of the study area including:

• Storm Drainage

• Sinkhole

• Pavement Surface

• Seawall

• Multi Use Trail

In addition, recommendations are made concerning the investigation and potential rehabilitation of storm drainage lines serving beach Channel Drive. Finally, a summary of estimated costs for the five project components is provided.

Storm Drainage The Savin report mentions two potential rehabilitation methods for the storm drainage system --- first, excavating and replacing defective pipe and secondly, l ining the pipe. Significant structural defects should be repaired by excavation and replacement, while functional defects may be repaired by use of a l iner.

The report identified two areas with significant structural deficiencies. The first is identified as the 377 linear feet of 30’’ concrete pipe connecting catch basin #10 (the northeastern most catch basin) to the outfall. Replacement of this pipe will involve excavation within Beach Channel Drive and impact to the sea wall. The second area with significant cracking and structural deficiencies is identified as the 280 linear feet between manhole 4 and catch basin 9. This area is located in the northeastern portion of the parking lot. Excavation and replacement is recommended for both of these sections of the storm drainage system.

The use of a resin liner was mentioned as an alternative to pipe replacement. Cost for this resin conduit liner varies and could exceed $400 per linear foot. This includes the cost of the lining process but does not include the pipe cleaning and pipe preparation that is required prior to l ining the pipe. The results of the Savin report indicate that several portions of the pipe network are covered with marine growth and penetrated by roots. The resin is best applied to a smooth pipe surface. Pipe sections to be lined will need to be thoroughly cleaned to remove sediment. The marine growth can be difficult to remove. To eliminate the possibility of soil infi ltration through existing

17 Recommendations and Cost Estimates cracks or pipe joints, it is recommended to l ine the section of 30’’ pipe between CB#3 and the outfall. Cured in place resin l iners result in minimal flow capacity reduction.

Parking Lot Sinkhole The area impacted by the sinkhole around catch basin 3 (as identified in the Savin report) is approximately 5,000 sf. Repairing this area should include excavating an area sufficient to replace a length of pipe in the upstream and downstream direction of the catch basin. This is required to replace the catch basin. It should be noted that the initial length of pipe in each direction is corrugated metal which then transitions to concrete pipe. The corrugated metal pipe should be removed and replaced with reinforced concrete pipe, thereby reducing the opportunity for infiltration where two dissimilar pipe materials join. Once the pipe upstream and downstream from the catch basin has been replaced, the pipe should be backfilled with suitable material and the concrete pavement should then be reconstructed in the excavated area.

The majority of broken and severely spalled slabs or slab sections w ill be repaired at the conclusion of the current Corp of Engineers project. In addition, the current project wil l restriped parking space and crosswalk pavement markings. In addition to the current surface repairs, all joints and cracks in the pavement surface should be repaired by cleaning, routing the cracks, and sealing to prevent future spalling, faulting, and breaking. Broken sections of concrete curb should be replaced.

Seawall The seawall inspection performed addressed only the portion of the wall that was visible above the waterline at the time of inspection. From the observations, there were no indications of distress to the wall due to instabil ity or severe compromise to structural integrity of the wall. However, since this investigation was limited to what was visible above water, an underwater investigation should be performed to inspect the base of the wall for localized scour and undermining, and signs that the wall is losing fill below the waterline.

There were no indications (remnants of broken anchor bolts or valve flanges) that check valves existed on the outfalls that penetrate the wall. There are a total of twenty (20) outfalls along the 4750+ feet of the seawall. It has been observed that there is a correlation between the location of the outfall pipes and sinkholes that have been forming behind the wall. Backflow into the outfall pipes due to the changing

18 Recommendations and Cost Estimates tides contribute to deterioration of the outfall pipes and potentially the loss of fines from behind the wall through joints in the pipes. Two (2) of the outfall, 30’’ diameter at station 12+20 and 36’’ diameter at 21+70 tie into the drainage system of the Jacob RIIS Park parking lot.

In conjunction w ith repairs to the outfall pipes coming from the Jacob RIIS Park parking lot, ‘‘duckbil l’’ check valves should be installed to prevent the backflow into the pipe by seawater during each tide cycle. The check valves should be attached to the outfall pipes and the concrete headwalls with stainless steel flanges. Check valves should be considered for the other eighteen (18) outfall pipes if they are repaired as fill from immediate behind the seawall may be being lost at those locations as well.

Several of the concrete headwalls of the outfall pipes have spalling and scaling deterioration. For the check valve to be installed and function properly, the headwall will be required to be repaired and/ or replaced, by removing the existing concrete headwall to sound concrete and replacing it in kind including epoxy coated or galvanized reinforcement.

The timber facing that was observed on the seawall face does not appear to be structural in nature due to the material type, size, install configuration, and it current state of deterioration with respect to the existing wall condition and stability. The timber facing may have served as form work when the seawall was built, as well as fendering for vessels and other object that may come in contact with the wall. Areas where the timber facing has completely deteriorated are showing signs of marine growth and concrete scaling. The timber facing may or may not be replaced;

however, by not replacing it, the seawall wil l be subject to direct exposure to the bay and subject to increased marine growth and wearing of the concrete surface due to the daily tidal shifts.

The concrete at several locations along the seawall above the timber facing is spalling, cracking with efflorescence, and has rust staining. Some of the cracking and spalls had resulted in failure of railing anchorage. Areas where the railing anchorage has failed and the areas where the top of the wall is cracked horizontally 12-inches +/ - below the top of the wall, the concrete should be removed and replaced including epoxy coated or galvanized reinforcement, and the rail ing anchorage reset.

Areas w ith spalled concrete, efflorescence, and rust staining should be further investigated/ sounded to define the extent of unsound concrete. The rust staining is a sign of corroded reinforcement. Area with rust staining are potential future spalls and will comprise the railing anchorage. If there is rust staining in areas where that require concrete repair due to railing anchorage damage and replacement, the concrete repair should be extended to include the rust stained areas. For safety purposes, all railing that is broken or loose should be repaired or replaced.

19 Recommendations and Cost Estimates

Multi Use Trail While intermittent sections of the multi-use trail along the top of the seawall are in serviceable condition, sections are in very poor condition due to deterioration of the pavement surface and the sinkholes that have formed behind the seawall. In addition, it is anticipated that some excavation in the vicinity of the multi-use trail may be required to repair storm drainage lines that run under the multi-use trail.

Therefore, it is recommended that the multi-use trail be reconstructed in its entirety after all of the drainage system repairs are complete and the adjacent sinkholes are permanently filled.

Beach Channel Drive Storm Drainage Lines A total of 20 pipes were observed to penetrate the Jamaica Bay seawall. Two of these pipes are confirmed to be outfalls from the Jacob Riis Park parking lot storm drainage system. The remaining 18 pipes are believed to be outfalls from Beach Channel Drive or other drainage systems. The location of most of the sinkholes observed along the seawall, including all large sinkholes, are in close proximity to one of the pipe outfalls. These locations are plotted on the detailed seawall mapping in Appendix E. As it is recommended that the storm drain lines from the parking lot be either replaced or l ined to prevent future soil infiltration from around the pipes, it is recommended that the other storm drain lines that penetrate the seawall be inspected using closed circuit TV, and appropriate measures be taken to prevent future soil infiltration from these lines as well. This work should be coordinated w ith any repairs to the seawall and the multi-use trail to assure a system wide solution.

20 Recommendations and Cost Estimates

Cost Summary A summary of the estimated costs associated with each of the recommended repairs described above is shown in the table below. Class C Cost Summaries for each feature shown in the table below are provided in Appendix G.

Feature Estimated Cost Storm Drainage

Replace 377 lf of 30’’ RCP between CB10 and Outfall $194,566 Replace 280 lf of 24’’ RCP between MH4 and CB9 112,024 Line 294 lf of 30’’ RCP between CB3 and the Outfall 289,470 CCTV Inspection of 18 Beach Channel Drive Drainage Lines 25,000

Storm Drainage Sub-total $621,060

Sinkhole Repair sinkhole by excavating, replacing pipe, backfi lling, and repaving

$131,279

Joint and Crack Repair and Curb Repair $2,784,849

Seawall Underwater Inspection $120,327 Install Check valves on NPS Outfalls on Seawall 185,118 Install Check valves on Other Outfalls on Seawall 814,518 Timber Facing 4,525,102 Concrete Repair 1,542,648 Railing Repair and Replacement 822,746 Seawall Sub-total $8,010,459

M ulti-Use Trail Remove and Reconstruct $539,702

Grand Total $12,087,349

21 Recommendations and Cost Estimates

The improvements outlined above are grouped in the table below into categories of Structural and Safety Improvements, Visitor Experience Improvements, and Infrastructure Preservation Improvements. It is recommended that the Structural and Safety Improvements receive the highest priority. The Visitor Experience Improvements are focused on restoring the condition of the top of the seawall, the seawall railing, and the multi-use trail, all of which will improve the usability and aesthetics of the seawall area. The Infrastructure Preservation Improvements are intended to prolong the need for additional future rehabilitation or maintenance to the seawall and parking lot.

Structural and Safety Improvements Estimated Cost Storm Drainage

Replace 377 lf of 30’’ RCP between CB10 and Outfall $194,566 Replace 280 lf of 24’’ RCP between MH4 and CB9 112,024 Line 294 lf of 30’’ RCP between CB3 and the Outfall 289,470 CCTV Inspection of 18 Beach Channel Drive Drainage Lines 25,000

Sinkhole Repair sinkhole by excavating, replacing pipe, backfi lling, and repaving

$131,279

Seawall Underwater Inspection $120,327 Install Check valves on NPS Outfalls on Seawall 185,118 Install Check valves on Other Outfalls on Seawall 814,518 Structural and Safety Improvement Sub-total $1,872,302

Visitor Experience Improvements Seawall Concrete Repair 1,542,648 Railing Repair and Replacement 822,746

M ulti-Use Trail Remove and Reconstruct $539,702 Visitor Experience Improvement Sub-total $2,905,096

Infrastructure Preservation Improvements Seawall Timber Facing 4,525,102

Pavement Surface Joint and Crack Repair and Curb Repair 2,784,849 Infrastructure Preservation Improvement Sub-total $7,309,951

22 Recommendations and Cost Estimates

Appendix A Location Map

Site Location

Jamaica Bay

Riis Landing

Floyd Bennet Field

Source: Esri, DigitalGlobe, GeoEye, i-cubed, USDA, USGS, AEX, Getmapping, Aerogrid, IGN, IGP, swisstopo, and the GIS User Community

\\ctmiddat\projects\xx\graphics\figures\figure_1.pdf

2,000 0 2,0001,000 Feet

Vanasse Hangen Brustlin, Inc.

Site Location Map Jacob Riis Park 157 Rockaway Beach Boulevard Queens, New York

E

Quadrangle Location

Appendix B

Study Area Map

ST

O

P

EXIT

BEACH CHANNEL DRIVE

ROCKAWAY BEACH BOULAVARD

ROCKAWAY BEACH BOULEVARDNEPONSIT AVENUE

NEWPORT AVENUE

IRIS AVENUE

CRONSTON AVENUE

BEACH 149TH STREET

BEACH 147TH STREET

BEACH 142TH STREET

BEACH CHANNEL DRIVE

Vanasse Hangen Brustlin, Inc.

\\CTMIDDAT\projects\33259.18 Riis_Parking\cad\ld\Planmisc\Riis_Overview Map.dwg

Jacob Riis Parking Lot Study Area Overview 157 Rockaway Beach Boulevard Queens, New York

July 25, 2014

Sheet 1 of 1

Appendix C Storm Drain Video Inspection

Report

Appendix D

Drainage Area Map

BEACH CHANNEL DRIVE

ROCKAWAY BEACH BOULAVARD

Vanasse Hangen Brustlin, Inc.

0 125 250 Feet

Drainage Area Map Jacob Riis Park - 157 Rockaway Beach Blvd.

Queens, New York

June 16, 2014

Appendix E Detailed Seawall Condition

Mapping

Vanasse Hangen Brustlin, Inc.

\\CTMIDDAT\projects\33259.18 Riis_Parking\cad\ld\Planmisc\33259.18 Riis_Seawall rev1.dwg

Jacob Riis Parking Lot Engineering Study - Seawall Inspection 157 Rockaway Beach Boulevard Queens, New York

Sheet 1 of 6

Jacob Riis Parking Lot Engineering Study - Seawall Inspection 157 Rockaway Beach Boulevard Queens, New York

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Jacob Riis Parking Lot Engineering Study - Seawall Inspection 157 Rockaway Beach Boulevard Queens, New York

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Jacob Riis Parking Lot Engineering Study - Seawall Inspection 157 Rockaway Beach Boulevard Queens, New York

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Jacob Riis Parking Lot Engineering Study - Seawall Inspection 157 Rockaway Beach Boulevard Queens, New York

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Jacob Riis Parking Lot Engineering Study - Seawall Inspection 157 Rockaway Beach Boulevard Queens, New York

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Appendix F Photo Documentation

Jacob Riis Park Parking Lot Engineering Study Seawall Inspection Photographs

Photo 1: Station 7+40 to 7+50 ‐ Small Existing Sinkhole

Photo 2: Station 11+40 to 11+80 ‐ Filled Sinkhole

Photo 3: Station 18+50 to 19+50 ‐ Filled Sinkhole

Photo 4: Station 22+50 to 25+00 – Series of Small Existing Sinkholes

Photo 5: Station 27+50 to 27+75 Existing Sinkhole

Photo 6: Station 28+75 – Large Existing Sinkhole

Photo 7: Station 29+00 to 29+75 – Large Existing Sinkhole

Photo 8: Station 30+70 – Existing Sinkhole

Photo 9: Station 31+75 ‐ Existing Sinkhole

Photo 10: Station 32+60 ‐ Large Existing Sinkhole

Photo 11: Station 33+50 ‐ Existing Sinkhole

Photo 12: Station 34+80 ‐ Existing Large Sinkhole

Photo 13: Station 35+60 ‐ Existing Sinkhole

Photo 14: Station 18+60 to 18+80 ‐ Missing Railing

Photo 15: Station 25+00 ‐ Railing with Missing Balusters

Photo 16: Station 26+50 ‐ Missing Railing and Balusters

Photo 17: Station 7+50 – Outfall Headwall for 18‐inch Pipe

Photo 18: Station 8+00 – Spalled Concrete

Photo 19: Station 8+00 ‐ Timber Separating from Wall

Photo 20: Station 10+80 – Spalled Concrete with Corroded Reinforcement

Photo 21: Station 10+80 –Typical Timber Facing Deterioration (looking east)

Photo 22: Station 10+80 ‐ Typical Timber Facing Deterioration (looking west)

Photo 23: Station 11+45 – Cracked Concrete along Top of Wall

Photo 24: Station 12+20 – Outfall Headwall for 36‐inch Pipe

CKelsey Typewritten Text

CKelsey Typewritten Text

Photo 25: Station 12+00 to 13+00 – Cracked Concrete along Top of Wall

Photo 26: Station 16+20 ‐ Outfall Headwall for 18‐inch Pipe

Photo 27: Station 17+00 ‐ Typical Timber Facing Deterioration (looking west)

Photo 28: Station 17+00 ‐ Typical Timber Facing Deterioration (looking east)

Photo 29: Station 17+50 – Deteriorated Wall joint with Spalled Concrete

Photo 30: Station 18+25 ‐ Deteriorated Wall Joint

Photo 31: Station 19+80 ‐ Outfall Headwall for 12‐inch Pipe

Photo 32: Station 19+70 to 20+00 ‐ Spalled Concrete with Corroded Reinforcement

Photo 33: Station 19+70 to 20+00 ‐ Spalled Concrete with Corroded Reinforcement

Photo 34: Station 19+70 to 20+00 ‐ Spalled Concrete with Corroded Reinforcement

Photo 35: Station 22+30 ‐ Outfall Headwall for 16‐inch Pipe

Photo 36: Station 22+30 ‐ Typical Timber Facing Deterioration (looking east)

Photo 37: Station 22+30 ‐ Typical Timber Facing Deterioration (looking east)

Photo 38: Station 22+70 ‐ Outfall Headwall for 30‐inch Pipe

Photo 39: Station 22+70 to 23+40 – Missing Timber Facing (looking east)

Photo 40: Station 24+30 – Spalled Concrete with Exposed Reinforcement

Photo 41: Station 27+20 ‐ Outfall Headwall for 12‐inch Pipe

Photo 42: Station 29+40 to 37+40 – Heavily Deteriorated Timber Facing (Sta. 31+00 shown)

Photo 43: Station 29+40 to 37+40 – Heavily Deteriorated Timber Facing (Sta. 33+00 shown)

Photo 44: Station 29+70 ‐ Outfall Headwall for 12‐inch Pipe

Photo 45: Station 32+30 ‐ Outfall Headwall for 18‐inch Pipe

Photo 46: Station 34+70 ‐ Outfall Headwall for 16‐inch Pipe

Photo 47: Station 36+10 – Spalled Concrete with Exposed Reinforcement at Wall Joint

Photo 48: Station 36+60 ‐ Outfall Headwall for 18‐inch Pipe

Photo 49: Station 38+50 ‐ Outfall of a 16‐inch Pipe, No Distinct Headwall

Photo 50: Station 41+00 ‐ Outfall of a 16‐inch Pipe, No Distinct Headwall

Photo 51: Station 43+50 to 43+75 ‐ Outfall of Three Pipes, No Distinct Headwalls

Photo 52: Station 45+00 ‐ Outfall of an 18‐inch Pipe, No Distinct Headwall

Photo 53: Station 46+50 (144th Street) ‐ Outfall of Two Pipes, No Distinct Headwalls

Photo 54: Station 48+30 ‐ Outfall of an 18‐inch Pipe, No Distinct Headwall

Photo 55: Various Locations ‐ Missing Timber with Marine Growth and Concrete

Photo 56: Various Locations ‐ Missing Timber with Marine Growth and Concrete

Photo 57: Station 44+00 ‐ Missing Timber with Marine Growth and Concrete

Pavement Condition Photographs

Photo 58: General Pavement Condition.

Photo 59: Deteriorated patch near entrance.

Photo 60: Patched and deteriorated slabs near entrance.

Photo 61: Pavement and median condition east of CB #1.

Photo 62: Deteriorated curb near CB #1.

Photo 63: Pavement and median near CB #2.

Photo 64: Broken and depressed slab near CB #9.

Photo 65: Beach Channel Drive transverse crack north of CB #3.

Appendix G Cost Estimates

United States Department of the Interior

Class C Construction Cost Estimate

BASIS OF ESTIMATE

195485 6/20/2014

GRD

860-807-4300

The purpose of this project is to conduct field investigations to identify existing conditions of the storm drainage system, pavement surface, and seawall and develop recommended repairs and estimated costs based on an engineering analysis of the existing conditions.

See additional sheet for details of estimate assumptions

2006 RSMeans Heavy Construction Cost Data and the 2006 RSMeans Site Work and Landscape Cost Data.

NYSDOT online Pay Item Catalog Manufacture's material quote General information from local contractors

Wethersfield, CT

Jacob Riis Park Parking Lot & Seawall - Storm Drain SystemProject:

Company:

Address:

City, State Zip:

Phone:

Park:

PMIS Number:

Estimate Date:

Park Alpha: GATE

PROJECT INFORMATION

BACKGROUND SUPPORTING MATERIAL (Scope of Work):

SOURCE OF COST DATA:

ESTIMATE ASSUMPTIONS:

MAJOR CHANGES FROM PREVIOUS ESTIMATE:

VHB

100 Great Meadow Road

Prepared By:

Gateway National Recreation Area

ClassCConstCostEstimate - Riis Storm Drainage Basis of Estimate Page 1 of 3 Print Date: 6/20/2014

Class C Construction Cost Estimate

BASIS OF ESTIMATE

195485 6/20/2014

Jacob Riis Park Parking Lot & Seawall - Storm Drain SystemProject:

Park:

PMIS Number:

Estimate Date:

Park Alpha: GATE

PROJECT…