ENCINA WASTEWATER AUTHORITY YEAR 2015 … EWA Outfall...ENCINA WASTEWATER AUTHORITY YEAR 2015 OCEAN OUTFALL INSPECTION ... Cathodic protection ... Ocean Outfall Inspection and Maintenance

ENCINA WASTEWATER AUTHORITY

YEAR 2015 OCEAN OUTFALL INSPECTION AND MAINTENANCE

Prepared for:

Encina Wastewater Authority Contact: Mr. Jimmy Kearns

6200 Avenida Encinas Carlsbad, CA 92011 Phone: 760-268 8812 Fax: 760-476-9852

E-mail: [email protected]

Prepared by:

EcoSystems Management Associates, Inc. 2166 Avenida de la Playa, Suite E

La Jolla, CA 92037

31 June 2015 ECO-M Reference No. 15-04

Encina Wastewater Authority Year 2015 Ocean Outfall Inspection and Maintenance

EcoSystems Management Associates, Inc. i Technical Report ECO-M Reference No. 15-04

TABLE OF CONTENTS

EXECUTIVE SUMMARY .......................................................................................................... v

FOREWORD............................................................................................................................... vii

1.0 INTRODUCTION.............................................................................................................. 1 1.1 OUTFALL CONFIGURATION ............................................................................ 1

2.0 INSPECTION PROCEDURES ...................................................................................... 12 2.1 VESSEL AND EQUIPMENT .............................................................................. 12 2.2 GENERAL PIPELINE INSPECTION ................................................................. 13 2.3 KELP CLEARING ............................................................................................... 14 2.4 OUTFALL MONUMENTATION ....................................................................... 14 2.5 MANHOLE INSPECTION .................................................................................. 14 2.6 DIFFUSER PORT INSPECTION AND MAINTENANCE ................................ 14 2.7 CATHODIC PROTECTION EVALUATION ..................................................... 15

3.0 RESULTS AND DISCUSSION ...................................................................................... 19 3.1 GENERAL PIPELINE INSPECTION ................................................................. 19 3.2 END STRUCTURE INSPECTION ...................................................................... 20 3.3 DIFFUSER PORT INSPECTION ........................................................................ 20 3.4 DEBRIS CLEARING ........................................................................................... 21 3.5 CATHODIC PROTECTION (CP) ....................................................................... 21 3.6 KELP CLEARING ............................................................................................... 22 3.7 BALLAST LOGGING ......................................................................................... 22 3.8 OUTFALL MONUMENTATION ....................................................................... 23 3.9 MANHOLE INSPECTION .................................................................................. 23

4.0 SUMMARY AND RECOMMENDATIONS ................................................................. 46 4.1 RECOMMENDATIONS ...................................................................................... 47

5.0 REFERENCES ................................................................................................................. 48

LIST OF APPENDICES Appendix A. Video Record of Inspection ................................................................................ A-1 Appendix B. Equipment Used For Surveys and Equipment Specifications .............................B-1 Appendix C. Photos of All 136 Diffuser Ports ..........................................................................C-1 Appendix D. Photos of Typical and Specific Areas of Interest Observed During Surveys ..... D-1

LIST OF FIGURES

Figure 1-1. Project vicinity map ....................................................................................................3 Figure 1-2. Encina Wastewater Ocean Outfall schematic .............................................................4 Figure 1-3 Schematic of shoreward portion of Encina outfall based on diver

investigation of inshore area. ......................................................................................5 Figure 1-4. Sketch of Encina Outfall .............................................................................................6 Figure 1-5. Sketch of Active Diffuser Section of Outfall ..............................................................6


EcoSystems Management Associates, Inc. ii Technical Report ECO-M Reference No. 15-04

Figure 1-6. Sketch of current transition section ...........................................................................10 Figure 1-7. Abandoned 48-inch pipe cap. Photo from Diver survey on 13 June 2015 ...............10 Figure 1-8. Sketch of 48-inch pipe sealing clamp .......................................................................10 Figure 1-9. Sketch of outfall end structure ..................................................................................11 Figure 1-10. Picture of outfall end structure. Photo from 6 December 2012 ROV survey ...........11 Figure 1-11. Sketch of Tie-Rod (found across joints near end of pipe) ........................................11 Figure 1-12. Picture of intact Tie-Rod. Photo from 9 June 2015 ROV survey .............................11 Figure 2-1. M/V Pacific Venture Charter Vessel .........................................................................16 Figure 2-2. Polatrak CP-Gun for cathodic protection measurements ..........................................17 Figure 2-3. Galvanic series ..........................................................................................................18 Figure B-1. Pacific Venture survey vessel and specifications ...................................................B-2 Figure B-2. Seaeye Falcon ROV ................................................................................................B-3 Figure B-3. Seaeye Falcon ROV specifications .........................................................................B-4 Figure B-4. Trackpoint II Plus Navigation System overview ....................................................B-5 Figure B-5. TSS Meridian Surveyor Gyrocompass overview ...................................................B-6 Figure B-6. Trimble Ag GPS 132 overview ..............................................................................B-7 Figure B-7. Hypack Navigation Software overview ..................................................................B-9

LIST OF TABLES Table 1-1. Diffuser port location and numbering system .............................................................7 Table 1-2. Encina Wastewater Outfall approximate positions .....................................................9 Table 3-1. Diffuser port inspection results .................................................................................24 Table 3-2. Cathodic protection readings ....................................................................................28

LIST OF PHOTOS Photo 2-1. One of three significantly deteriorated sacrificial zinc anodes attached to

48”sealing clamp. These zinc anodes are still providing adequate cathodic protection (-0.99 to -1.1 VDC) .................................................................................17

Photo 3-1. Encrusted ballast on top of 48-inch pipe section, just east of transition zone. Note abundant marine growth ...................................................................................29

Photo 3-2. 72-inch pipe section just east of diffuser ports. Note lack of marine growth and lack of concrete spalling (14:42:12 of ROV video) ...........................................29

Photo 3-3. Pipe Joint with intact Reaction Tie between Diffuser Port pipe section and end gate structure (13:30:37 of ROV video) .............................................................30

Photo 3-4. Pipe Joint with broken Reaction Tie between Diffuser Port #’s 15 and 17 from 2012 survey (17:24:53 of North Side - Video 1) .............................................30

Photo 3-5. Typical small rock ballast along 72-inch pipe section. Photo near Diffuser Port #133. (12:33:21 of ROV video) ........................................................................31

Photo 3-6. Typical large rock ballast along outfall endgate structure. Large structure in back is side of endgate (13:30:44 of ROV video ......................................................31

Photo 3-7. Ballast size change around Outfall End Structure. Ballast around End Structure is much larger (17:04:12 of South Side – Video 3 – 2012 photo) ............32


EcoSystems Management Associates, Inc. iii Technical Report ECO-M Reference No. 15-04

Photo 3-8. Typical ballast along 48-inch diameter pipe, near transition zone (18:14:40 of North Side – Video 2) ...........................................................................................32

Photo 3-9. Sealing clamp with deteriorated zinc anodes on 48-inch diameter pipe in western part of transition zone (15:010:03 of ROV video ........................................33

Photo 3-10. Abandoned 48-inch Pipe Cap at east end of transition zone (15:10:03 of ROV video) ...............................................................................................................33

Photo 3-11. Transition zone hardware, where CP readings were taken (00:01:30 of Diver video) ........................................................................................................................34

Photo 3-12. Outfall End Structure – Looking from south. From 2012 survey. (17:04:30 of South Side – Video 3) ...........................................................................................34

Photo 3-13. Outfall End Structure – Looking from west. from 2012 survey. (17:05:22 of South Side – Video 3) ...............................................................................................35

Photo 3-14. Slot Cover at west end of Outfall End Structure from 2015 survey. Note absence of effluent coming from bottom end of slot cover ......................................35

Photo 3-15. Port on north side of endgate structure, no flow. (13:31:11 of ROV video) ............36 Photo 3-16. Port on south side of endgate structure, no flow. (13:37:06 of ROV video) ............36 Photo 3-17. Diffuser Port #17. (Round circle). it appears this port was drilled but the

concrete plug was never removed. (13:15:00 of ROV video) ..................................37 Photo 3-18. ROV manipulator pushing in on Diffuser Port #17. Note effluent escaping.

Plug immediately went back in place upon release by manipulator .........................37 Photo 3-19 Beginning of short (approx 15-ft. uncovered section of 48-inch pipe just

west (seaward) of Manhole 4. (00:45 of Diver video) ..............................................38 Photo 3-20 Intersection of 48-inch pipe and Manhole 5. (00:42 of Diver video) .......................38 Photo 3-21 Manhole 6 Station 49+72 (00:14:30 in Diver Video) ...............................................39 Photo 3-22 Exposed Pipe east of Manhole 6. Station 50+00 (00:13:50 in Diver Video) ...........39 Photo 3-23. Manhole 5 Station 42+05 (00:27:59 in Diver Video) ...............................................40 Photo 3-24. Exposed Pipe and joint east of Station 42+05, near Manhole 5 (00:27:30 in

Diver Video) .............................................................................................................40 Photo 3-25. Manhole 4 Station 33+99 (00:45:40 in Diver Video) ...............................................41 Photo 3-26. Exposed Pipe east of Manhole 4 ~Station 34+00 (00:45:22 in Diver Video) ..........41 Photo 3-27. Manhole 3 Station 25+78 (00:57:38 in Diver Video) ...............................................42 Photo 3-28. Exposed Pipe east of Manhole 3 ~Station 26+00 (00:57:30 in Diver Video) ..........42 Photo 3-29. Top of Manhole 2 Station 18+10 (01:15:25 in Diver Video) ...................................43 Photo 3-30. Exposed Pipe east of Manhole 2 ~ Station 18+25 (01:15:09 in Diver Video) .........43 Photo 3-31. Manhole 1 Station 10+42 (01:31:14 in Diver Video) ...............................................44 Photo 3-32. Exposed Pipe east of Manhole 1 ~ Station 12+25(01:28:53 in Diver Video) ..........44 Photo 3-33. Cathodic Protection Reading from transition zone hardware (-0.999 VDC) ............45 Photo 3-34. Cathodic Protection Hardware at 48” sealing clamp transition to 72” pipe .............45 Photo D-1. Station Marker 42+05 – Manhole 5. (00:27 of Diver video) ................................. D-2 Photo D-2. Typical marine life covering outfall pipe in western part of 48-inch pipe

section .................................................................................................................... D-2 Photo D-3. Typical marine life (sea anemones) around diffuser ports. From 2012

survey. (16:50:09 of South Side – Video 3) .......................................................... D-3 Photo D-4. School of fish above ballast covering 48-inch section of outfall, near

Manhole 5 (00:27 of Diver video) ......................................................................... D-3


EcoSystems Management Associates, Inc. iv Technical Report ECO-M Reference No. 15-04

Photo D-5. Rigging the USBL transducer mount before the ROV survey commenced .......... D-4 Photo D-6. ROV in water. From 2012 survey. Same ROV was used in 2015 ......................... D-4


EcoSystems Management Associates, Inc. v Technical Report ECO-M Reference No. 15-04

EXECUTIVE SUMMARY EcoSystems Management Associates, Inc. (ECO-M) performed the Year 2015 Encina

Ocean Outfall Inspection and Maintenance at the request of the Encina Wastewater Authority (EWA) between 9-15 June 2015. The work first involved a remotely operated vehicle (ROV) inspection of the deeper reaches of the outfall from Manhole 5 (Station 42+05) to the seaward end of the outfall at Station 77+66. These areas were videotaped by means of a SAAB Falcon ROV. The vehicle performed diffuser port inspection and maintenance, as required. The ROV also inspected the end structure at the seaward end of the outfall.

Second, the inspection involved a diver examination of the nearshore sector from

Manhole 1 (Station 10+42) to Station 55+92 of the outfall pipeline, including continuous videography along the outfall, taking cathodic protection readings along the exposed metal portion of the sealing clamp within the transition section, and diver and video evaluation of the six exposed manholes.

Video documentation was collected along the entire outfall. The purpose of the inspection was to look for evidence of spalling of the exposed concrete surfaces, cracks, or other deficiencies in the outfall, joint integrity, leaks or evidence of degradation, diffuser flow rates, potential hazards, and attrition or the loss of efficacy of the ballast material. MAJOR FINDINGS General Inspection

• Overall, the Encina Ocean Outfall was found to be in good condition. • During this survey, no areas of spalling were found; there were no signs of rust staining

or cracking; and there was no leakage from any pipe joints along the outfall. • The six sealed manholes were inspected and found to be in good condition.

End Structure

• The End Structure, Bulkhead and Scour Pad were generally found to be in good shape. • No flow was seen coming from the two side ports on the End Structure, similar to the

results of the 2012 inspection survey. • The ROV videotape did not show any effluent leakage along the base of the slot cover of

the endgate. Minor effluent leakage was seen in the 2012 video inspection. Diffuser Ports

• Almost all of the 136 Diffuser Ports exhibited good flow. • The only entirely obstructed Port was #17, on the north side of the outfall. This Port has

been obstructed in all previous reports reviewed by ECO-M. It appears as though this Port was drilled but that the plug was apparently not removed.

• Diffuser Port #27 exhibited reduced flow. The ROV manipulator was used to clear this port with some success.

• Exterior surfaces of several of the diffuser port openings had soft marine growth, which did not appear to reduce aperture sizes.


EcoSystems Management Associates, Inc. vi Technical Report ECO-M Reference No. 15-04

• Several of the diffuser ports were very close to or within the ballast material; these ports were flowing freely nevertheless. Diffuser port #79 could not be seen by the ROV.

Debris Clearing

• Very little debris was encountered during either the diver survey or the ROV survey, contrary to several previous survey results reviewed by ECO-M.

• No lobster pots or other fishing gear were seen during the survey, contrary to previous surveys.

Cathodic Protection

• No connected zinc anodes were seen during the diver inspection of the six manholes. • Cathodic protection readings were taken with a silver/silver chloride reference cell along

the Transition Zone sealing clamp. The three zinc anodes were significantly deteriorated but after cleaning, gave readings between -0.99 and -1.1 VDC, which represents complete cathodic protection.

Kelp Cleaning

• The divers cleared the moderately heavy kelp growth attached to the outfall pipe and the surrounding ballast rock seaward of Manhole 1. Divers were precluded from working inshore of Manhole 1 by a California State Lifeguard who specifically excluded our vessel.

Ballast Logging

• No significant ballast losses were observed, nor were any sections being undermined, which might result in free spans.

• All ballast rock along the pipe was stable and showed no significant signs of movement. RECOMMENDATIONS

• As has been recommended in previous inspection reports, the EWA should continue to

perform “rapid-response” overview inspections after periods of extremely high surf or seismic activity to identify damage and potential for failure due to scour, high-velocity currents, or major seafloor movements. We are not aware that any call-out inspections have ever been conducted.

• The EWA should also continue preventative maintenance, including kelp clearing; and perform detailed periodic inspections of the entire pipeline according to their current practice.

• The EWA may wish to consider future replacement of the zinc anodes on the transition structure between the 48-in. and 72-in. pipes; these anodes appeared to be severely deteriorated, but are still currently providing adequate protection.


EcoSystems Management Associates, Inc. vii Technical Report ECO-M Reference No. 15-04

FOREWORD

The Encina Ocean Outfall, which extends offshore from the coast of Carlsbad, California was completed in 1975 to discharge treated effluent through an 800-ft-long diffuser section into the water column approximately 1.48 miles from the Encina Treatment Plant. The average amount of treated wastewater is 22-million-gallons per day (MGD).

The outfall facilities were constructed in several phases. The original 48-inch diameter

reinforced concrete pipe (RCP) was installed in 1965 and extended approximately 5,500 ft seaward where it discharged effluent at a depth of approximately 100 ft. mean lower-low water (MLLW). In 1974, a 72-inch diameter RCP extension approximately 2300-ft-long moved the discharge diffuser section to water depths between approximately 135 and 170 ft. MLLW. A tapered, bell-shaped transition section connects the 48-inch internal diameter (ID) and 72-inch ID pipes. The diffuser ports in the 48-inch pipeline were sealed at this time.

In order to comply with environmental regulations regarding discharges into marine

waters and increasing demands on the infrastructure over the past four + decades, it has been imperative that the pipeline be maintained and monitored for potential damage. To this end, the EWA Joint Powers Authority (JPA) has contracted numerous inspection surveys of the outfall pipeline.

This report presents the results of the 2015 outfall survey performed by ECO-M. Given

the large volume of information collected during previous monitoring events, we have excerpted pertinent data products from several previous reports. Some of the language, figures, and data presented in this report have been borrowed from previous monitoring reports prepared for the Encina Water Pollution Control Facility (EWPCF) by Thales GeoSolutions Pacific Inc., Pelagos Corporation, Racal Pelagos, Undersea Graphics, Inc. (UGI), and ECO-M. The contributions of individual reports are acknowledged here, as well as cited in this document. The reports and their contents are the property of EWA JPA and are on file in their archive.


EcoSystems Management Associates, Inc. 1 Technical Report ECO-M Reference No. 15-04

ENCINA WASTEWATER AUTHORITY YEAR 2015 OCEAN OUTFALL INSPECTION AND MAINTENANCE

1.0 INTRODUCTION

The Encina Wastewater Authority contracted ECO-M to perform the Year 2015 Ocean Outfall inspection. Shallow-water diving operations were completed between 13-15 June 2015, and the deeper reaches were inspected using a Falcon ROV on 09 June 2015. The inspection effort included the following elements:

1. General diver and ROV overview inspection of the outfall for the following criteria:

evidence of spalling of the exposed concrete surfaces, cracks, or other deficiencies in the outfall; joint integrity; leaks or evidence of degradation; potential hazards; areal extent, type and density of bio-fouling; attrition or the loss of efficacy of the ballast material as a result of physical, biological, or geological processes; scouring of the nearby marine sediments; and manmade debris.

2. Clearing kelp that hindered inspection activities or threatened the protective ballast material.

3. Monumentation along the outfall with station number for positioning by diver inspectors and the video documentation.

4. Inspection of exposed manholes.

5. Evaluation of cathodic protection.

6. Video inspection of 136 diffuser ports along the 800-ft-long diffuser section of the pipe; ROV manipulator clearance attempt of clogged diffuser ports and removal of small obstructions, such as abandoned fishing gear.

7. ROV inspection of the end structure of the pipe.

8. Video documentation of the entire exposed outfall and its protective ballast.

Procedures, results, analyses, and implications are reviewed for all elements comprising this project. Digital video and still images support written descriptions. Full copies of the videography are included with this report. 1.1 OUTFALL CONFIGURATION

The Encina Outfall’s location, approximate GPS coordinates, and configuration are shown in Figures 1-1 to 1-12, and Tables 1-1 and 1-2, below. Figure 1-1 places the pipeline in the context of coastal San Diego County. Figure 1-2 is a schematic illustration of the specific elements of the outfall. Figure 1-3 is an estimated schematic illustration of the inner (shoreward) portion of the outfall based on the diver’s investigation during this survey. Figure 1-4 is a sketch of the outfall and Figure 1-5 is a sketch of the diffuser section of the outfall, both done by UGI. Figure 1-5 shows the numbering system for the diffuser section; odd numbered ports are on the north side of the pipe and even numbers on the south side. The numbers begin at the seaward end



of the outfall and increase towards shore. There are 136 diffuser ports total, 68 on each side of the pipe.

Table 1-1 lists the diffuser ports and their relation to the pipe joints, as well as showing

their locations. Table 1-2 list the approximate GPS locations and water depths for the various portions of the outfall. The GPS coordinates are from the survey vessel’s onboard Furuno GPS system. They are approximate.

Figure 1-6 is a drawing created by UGI showing the current configuration of the

transition section of the outfall where the ID increases from 48 inches to 72 inches. Figure 1-7 is a video capture photo from the June 13 diver survey, showing the transition section, specifically the abandoned 48-inch (in.) pipe cap. Figure 1-8 is a drawing by UGI showing the 48-in. pipe sealing clamp. The transition section was covered by sediment and heavy marine growth, so the transition section and sealing-clamp details could not be identified by the videography. Figure 1-9 is a drawing created by UGI showing the configuration of the end structure of the outfall pipe, and Figure 1-10 is a video capture photo from the December 2012 survey by ECO-M, showing the end structure. Figure 1-11 is a UGI sketch of a reaction-tie (tie-rod) assembly, which is used to assist in holding two sections of pipe together across a joint, especially important, immediately post- installation. Figure 1-12 is a still capture taken from the 9 June 2015 survey, showing an in-place reaction-tie assembly. Reaction ties were installed across the seven seaward-most offshore pipe joints.

The outfall pipe is buried in the cobbles and sand as it proceeds offshore from the Encina

Treatment Plant. It currently emerges from the littoral sand near Station 7+50, at approximately 15 ft. below MLLW. This emergence point varies between years and seasons, depending on the strength of the waves. The pipe’s elevation generally follows the natural seafloor slope to its terminus, approximately 8,000 ft from shore. Treated effluent is diffused through the 136 ports (68 per side), 12 feet apart, in an 800-ft-long diffuser section at the seaward end of the outfall. The end of the outfall is at approximately 175 ft below MLLW.



Figure 1-1. Project vicinity map.



Figure 1-2. Encina Wastewater Ocean Outfall schematic.



Figure 1-3. Schematic of shoreward portion of Encina outfall-based on diver investigation of close inshore area.



Figure 1-4. Sketch of Encina Outfall (from UGI, 2011).

Figure 1-5. Sketch of Active Diffuser Section of Outfall (from UGI, 2011).



Table 1-1. Diffuser port location and numbering system. (Joint data from Table 1 – 1999 Outfall Inspection – by Racal Pelagas, Inc.)

Joint # (From

Extension)

Diffuser Number

Location (Side of

Pipe)

Joint #

(From Ext.)

DiffuserNumber

Location(Side of

Pipe)

Joint #

(From Ext.)

Diffuser Number

Location(Side of

Pipe)

94

1 North 87

31 North

79

61 North 2 South 32 South 62 South 3 North

86

33 North 63 North 4 South 34 South 64 South

93

5 North 35 North

78


85


92

9 North 39 North

77


84


91

13 North 43 North

76


83


90

17 North 47 North

75


82


89

21 North 51 North

74


81


88

25 North 55 North

73


80


87 29 North 59 North

72 89 North

30 South 60 South 90 South



Joint # (From

Extension)

Diffuser Number

Location (Side of

Pipe)

Joint #

(From Ext.)

DiffuserNumber

Location(Side of

Pipe)

Joint #

(From Ext.)

Diffuser Number

Location(Side of

Pipe)

72 91 North

68 107 North

64 123 North

92 South 108 South 124 South

71

93 North

67

109 North

63

125 North 94 South 110 South 126 South 95 North 111 North 127 North 96 South 112 South 128 South

70

97 North

66

113 North

62


69

101 North

65

117 North

61


68 105 North

64 121 North

106 South 122 South



Table 1-2. Encina Wastewater Outfall approximate positions.

Encina Wastewater Outfall Approximate Positions

Description Station NumberSeafloor depth

(ft) aprox. Lat-NAD83 Long-NAD83UTM-m-northing

NAD83UTM-m-easting

NAD83Start of 48" outfall 0+00Transition Joint 7+09 15

Pipe Emerges from sand

9+70 to 11+70 (depending on

year) 20 to 24Manhole 1 10+42 22 33 06.8677460 117 19.6882378 3664024.3 469386.4Manhole 2 18+10 34 33 06.8338570 117 19.8325784 3663962.4 469161.7Manhole 3 25+78 47 33 06.8007171 117 19.9782925 3663901.8 468935.0Manhole 4 33+99 60 33 06.7615056 117 20.1326500 3663830.2 468694.7Manhole 5 42+05 73 33 06.7353950 117 20.2869279 3663782.7 468454.7Manhole 6 49+72 86 33 06.6997673 117 20.4331777 3663717.6 468227.0Transition Zone from 48-inch to 72-inch pipe 54+90 to 55+92 96 33° 06.671' 117° 20.530' 3663664.9 468076.9Reaction Ties 76+08 170End Structure 77+76 175 33° 06.561' 117° 20.960' 3663463.9 467407.3

Description Length (ft) Seafloor depth

(ft) aprox. Lat-NAD83 Long-NAD83UTM-m-northing

NAD83UTM-m-easting

NAD83Depth

Range (ft)

Port Sections Quanitity DiameterLength (ft)

(aprox) odd #'s North even #"s SouthPorts Inshore 43 44 (#'s 93-136) 2.5" 252.8 93-135 94-136Ports Mid 43 44 (#'s 49-92) 2.75" 252.8 49-91 50-92Ports Last 48 48 (#'s 1-48) 3" 282.2 1-47 2-48

467642.1 135-170Start of Diffuser Ports - 136 Total 800 165 33° 06.605' 117° 20.809' 3663544.4



Figure 1-6. Sketch of current transition Figure 1-7. Abandoned 48-inch pipe cap. section (from UGI, 2011). Photo from Diver survey on 13 June 2015.

Figure 1-8. Sketch of 48-inch pipe sealing clamp (from UGI, 2011).



Figure 1-9. Sketch of outfall end structure Figure 1-10. Picture of outfall end structure. (from UGI, 2011). Photo from 6 December 2012 ROV survey.

Figure 1-11. Sketch of Tie-Rod (found across Figure 1-12. Picture of intact Tie-Rod. joints near end of pipe) (from UGI, 2011). Photo from 9 June 2015 ROV survey.



2.0 INSPECTION PROCEDURES Numerous techniques were incorporated in executing the inspection tasks, which were

tactically arranged to maximize efficiency. The ROV survey was performed first (on June 9th) and proceeded along the north side to the end structure, beginning just west of the transition section, near Manhole 6, and surveying westerly out to the end. The diffuser ports on the north side were surveyed first starting with # 135 and ending with # 1. Next the endgate structure was inspected, followed by the south side diffuser ports, beginning with # 2 and proceeding easterly. After inspecting all the southside diffuser ports; the transition zone, Manhole 6 and Manhole 5 were attempted to be inspected by the ROV. Because of the growth around the pipe, this outer portion of the 48-inch wide section of pipe was difficult to delineate clearly using the ROV videography.

Starting on June 13, the diver survey was performed beginning with the transition zone and working shoreward. The dive staff worked from deep water to shallow in the interest of optimizing daily bottom time. The diver video of the transition zone and manholes is much clearer than the ROV video of these sections, as well as being much clearer than during the 2012 survey, due to better water visibility conditions this time. 2.1 VESSEL AND EQUIPMENT

For both the ROV and dive surveys, the M/V Pacific Venture (Figure 2-1), a 42-ft charter

vessel, was employed. The vessel was equipped with all essential diving, navigational, and inspection equipment. The vessel is harbored at the Oceanside Marina, from which all surveys began. A 500-lb capacity davit was installed on the vessel and used to deploy and recover the ROV. The large cabin and bridge housed the crew and all the equipment used for navigation (both vessel and ROV), and ROV controls and video monitors.

The following navigation equipment was used to vector the ROV along the outfall and

acquire positioning data throughout the ROV inspection: one acquisition computer capable of running the Trackpoint II Plus navigation system; one Trimble Ag GPS 132 Receiver, one TSS Meridian Surveyor Gyrocompass (vessel heading and position), as well as Hypack Navigation Software.

For the ROV survey, the survey team included: the vessel operator, the ROV operator,

the navigation specialist, a deckhand, and the ECO-M supervisor, Mr. William Speidel. For the diver survey, the survey team included: the vessel operator, four experienced divers, a deckhand and Mr. Speidel.

The navigation specialist operated the integrated surface/USBL acoustic Trackpoint

navigation software, which was used to monitor the position of the surface vessel and the ROV, and to provide a USBL (ultrashort baseline acoustic tracking) derived position to the vessel master and ROV pilot; this system also logged all position data during the entire underwater inspection. During mobilization, the ECO-M team measured offsets (via tape measurements) of the CRP (common reference point), the USBL head, the surface vessel outline, and any other necessary locations, as well as performing a dockside calibration of the USBL system.



The Trimble 132 was configured to accept OmniSTAR corrections and provide G2

positioning. G2 combines the navigation satellites of both the American GPS constellation and the Russian GLONASS constellation to produce a composite GPS/GLONASS position solution. The horizontal datum was ITRF08. During survey operations, the integrated surface/acoustic systems provided GPS position, heading, and ZDA (GMT) time stamp to the surface vessel and ROV positions. The navigation operator monitored the integrity of the Trimble’s position and heading, as well as the USBL-derived position throughout the survey. Data logging was setup to record position fixes at one-second intervals; in addition, the operator acquired manual fixes upon demand, as needed. All navigation equipment was calibrated on the Pacific Venture before beginning the ROV survey.

Specification sheets and pictures of the equipment used can be found in Appendix B of this report. 2.2 GENERAL PIPELINE INSPECTION

ECO-M conducted a general overview inspection of the entire exposed portion of the

outfall. During operations, diving staff were attentive to the criteria cited earlier in the introduction.

General pipeline inspection was achieved with a combination of visual and video techniques. Divers visually inspected the entire pipeline from the transition section to the point where the pipe becomes buried near shore. Dive teams set temporary location monuments and then swam with a hand-held video camera documenting the condition of the pipeline and ballast. The divers operated a GoPro Hero HD video system in an underwater housing illuminated by an Underwater Kinetics light source.

Two-person dive teams were used. For each team, one diver checked the cathodic

protection (CP), took notes, and assisted with the positioning tags, while the other diver videotaped. Diver video content used for this report was downloaded from the Go Pro to a laptop computer. Station markers were deployed by the divers to help with their underwater navigation and to orient the video viewer. Still images, which were captured to highlight typical and specific areas of interest observed during the survey, are included at the end of Section 3.

For video inspection of the deeper sections of the outfall, ECO-M deployed a Saab

Seaeye Falcon ROV. It has a maximum depth rating of 1,000 meters. The specifications are included in Appendix B. The ROV was installed on the M/V Pacific Venture using the installed davit. The ROV was remotely maneuvered along the outfall by the pilot, with its underwater position being tracked using USBL acoustic beacons mounted on the ROV. The acoustic transmissions (range and bearing) and responses were processed by the Trackpoint II Plus navigation system with the vessel and ROV positions displayed on the navigation monitors on the host vessel.



2.3 KELP CLEARING

Kelp clearing serves two important functions. First, clearing kelp (Macrocystis sp.) reduces the attrition of the ballast stones because large swells are able to lift the kelp, which is attached to the ballast rocks, causing the ballast to be “rafted” away from the outfall corridor. Secondly, removing kelp permits relatively unobstructed videography of the outfall and ballast pile and allows faster traverses by the divers.

2.4 OUTFALL MONUMENTATION

Vessel-based differential GPS was used to navigate to each (of the six) manholes where a

temporary buoy was deployed. Temporary monument tags were laid at 100-ft intervals between manholes along the top of the pipe from Station 55+92 (seaward of Manhole 6) toward shore until arriving at Manhole 1 (Station 10+42). A ground line was laid between each manhole to assist the divers in maintaining known positions on top of the pipeline while videotaping the pipeline corridor. The floating station markers served to directly identify the location of the video coverage.

2.5 MANHOLE INSPECTION

The following actions were completed for each of the six exposed manholes along the

outfall, located at stations 10+42, 18+10, 25+78, 33+99, 42+05, and 49+72.

• Visual inspection of each cover and riser for mechanical/structural integrity (leaks, fractures, gasket failure, concrete spalling, etc.).

• Inspection of the condition of the ballast and ocean bottom in the immediate vicinity of the manhole.

2.6 DIFFUSER PORT INSPECTION AND MAINTENANCE

During the deep water survey, the ROV was flown slowly along the 800-ft diffuser

section on both sides of the outfall and conditions monitored and recorded by the ECO-M team. The mother ship was outfitted with several video screens to allow for close monitoring of all areas surveyed by the ROV. All 136 diffuser ports were closely inspected and video recorded. If ports encountered were partially blocked, then the manipulator on the ROV attempted to clear the blockage.



2.7 CATHODIC PROTECTION EVALUATION

Corrosion potential of exposed metal surfaces were measured using a Polatrak CP-Gun, which uses two silver/silver chloride (Ag/AgCl) reference cells connected to two independent voltmeters, all housed in a rugged underwater housing (Figure 2-2). Measurements could be obtained along metal portions of the 48-in. sealing clamp within the transition section. At the transition zone, three sacrificial zinc anodes were observed, although significantly deteriorated (Photo 2-1), they were cleaned and still showed adequate protection (-0.99 to -1.1 VDC) (volts direct current). These zinc anodes are protecting the stainless steel slot covers which conceal a slot in the reinforced concrete pipe (RCP) which transitions to the 48-inch outfall. The slot covers were placed on the outfall when the old concrete cover was found to be leaking in 1991.

No zinc anodes were observed on any exposed portion of the Manholes. The lift bales

were the only steel structures visible on the manholes and these were not cathodically protected (-0.51 VDC). The sealing clamp and attached upper vent were the other transition zone structures that could be measured, and they displayed readings indicative of cathodic protection. There are very few metallic sites accessible on this pipeline because this outfall is constructed of RCP.

Many ocean structures are protected from the ocean’s corrosive environment by the use

of either an impressed-current cathodic protection system or by affixing sacrificial anodes to the structure. Forcing or impressing a direct current between an inert anode and the structure to be protected retards electrochemical corrosion of the metallic components of the outfall. Since electrons flow to the structure, it is protected from becoming the source of electrons (anode). Generally, in impressed current systems, a large anode bed is buried, and a low voltage direct current (DC) is impressed between the anode and the cathode (the metal being protected). This forces the electrochemical potential of exposed metal surfaces to be out of the voltage range within which electron loss (the anodic reaction) occurs. The electro-chemical series chart is shown in Figure 2-3.

The paragraph above is a generic treatise on the subject, but which does not particularly

pertain to the Encina outfall because it is RCP construction. During the early evolution of the Encina outfall design, several metallic elements were incorporated in the construction. Later improvements capped the metallic areas, reducing or eliminating the need for sacrificial anodes. It is possible that portions of the original inspection criteria have been carried forward to this day, even though they may not apply to the present configuration.



Figure 2-1. M/V Pacific Venture Charter Vessel.



Figure 2-2. Polatrak CP-Gun for cathodic protection measurements.

Photo 2-1. One of three significantly deteriorated sacrificial zinc anodes attached to 48”sealing clamp. These zinc anodes are still providing adequate cathodic protection (-0.99 to -1.1 VDC).



Figure 2-3. Galvanic series.



3.0 RESULTS AND DISCUSSION 3.1 GENERAL PIPELINE INSPECTION

The pipeline was originally covered with either beach sand, beach cobbles, or ballast from its origin to the end of the transition section near Station 55+00. Ballast covered the pipeline from the point where the pipe originally daylighted from the beach sand/cobbles near Station 9+20 to the transition zone, with beach sand and cobbles covering the pipeline shoreward from Station 9+20. Since that time, two general areas of the top of the pipeline have become exposed. One begins approximately 200-ft. west of Manhole 1 (near Station 12+50) and continues east for a few hundred feet. Only the top of the pipeline is exposed in this area. The other areas of exposed pipe are approximately 15 ft. sections in which the top of the pipe is exposed on the seaward (west) side of each manhole.

No spalling of the concrete was seen along any exposed portions of the outfall. All

exposed portions of the outfall support heavy encrustation by marine life, both plant and animal. A minor dusting of sediment covers the pipeline and ballast rock in most areas of the original portion of the pipeline (shoreward of Station 55+92), and algal growth obscures many of the details of the transition area. All six of the manholes are clearly visible and exposed along the original portion of the outfall (Figure 1-2). Except for those areas mentioned above, only the manholes are exposed along this 48-inch corridor. West of Station 55+00, the pipeline is generally well exposed and with fewer encrusting organisms, enabling easier examination for spalling or joint leaks by the ROV survey. Neither of these conditions was seen.

It is known that concrete immersed in seawater typically fails from chloride penetration

over time. This penetration weakens concrete bonds at the molecular level, resulting in a net loss of material strength. Concrete failure along ocean outfalls typically occurs where the outfalls have been serviced or where hybrid concrete mixes were used to help cure concrete. For these reasons, regular inspection of the RCP outfall should be continued.

Biofouling, or the undesirable accumulation of encrusting organisms, plants, and animals

on surfaces of the deeper pipeline sections was relatively sparse in most areas; most notable was the pink anemone Corynactis californica. These organisms are not expected to have an impact on the pipeline. Past surveys have shown substantial biofouling by giant kelp (Macrocystis pyrifera) in deeper sections; however, during this survey only occasional smaller plants were observed (juvenile and sub-adults with fewer than 8 stipes) in the deeper sections. The dominant fouling organisms are Corynactis californica and three gorgonians: Muricea californica, Muricea fruticosa, and Lophogorgia chilensis. These species should have no impact on the pipe or ballast and may actually be of benefit, by having such dense populations; they reduce the available substrate on which the giant kelp can become established.

There are reaction-tie-rods at the western end of the outfall pipe, which were installed to

help hold the pipe together at its most westerly joints. The ROV survey observed reaction tie-rods at the most westerly joints of the pipe. As with previous surveys, the reaction ties between diffuser ports 3 and 5, 7 and 9, 11 and 13, and 19 and 21 were still attached on each side of the joint. The ties between diffuser ports 15 and 17, and 23 and 25 were no longer attached across



the joints as one of the anchor brackets (Figures 1-11 and 1-12) was no longer attached to the pipe. This is not considered a situation that requires rectifying, as the ties are typically needed only immediately post-construction.

Visualization of the pipe sections and attributes discussed above and below are included

at the end of this section of the report (Photos 3-1 through 3-34), as well as on the two videos (Appendix A). 3.2 END STRUCTURE INSPECTION

The ROV was used to closely examine the endgate structure of the outfall (Figures 1-9

and 1-10), including the Bulkhead and Scour Pad. Overall, the endgate structure was observed to be in good condition. The ports seen in Figure 1-9, which are located on the north and south sides of the end structure, were not flowing (Photos 3-15 and 3-16). These ports were reported as having little or no flow in past inspection reports reviewed by ECO-M (See References – Section 5.0). The reaction tie that helps reinforce the connection between the end gate structure and the beginning of the diffuser ports section of pipe is still attached (Photo 3-3). The endgate structure lifting bail also appeared to be intact.

The slot cover at the very western end of the pipe was closely inspected by the ROV.

Unlike in the 2012 survey, no effluent was seen flowing from the endgate itself (Photo 3-14). During the 2012 survey, it appeared that there was a minor amount of effluent flowing from the base of this endgate. 3.3 DIFFUSER PORT INSPECTION

All 136 diffuser ports were inspected during the ROV survey. The ROV survey started on the south side of the pipe (just west of the transition section) and was maneuvered to the west slowly inspecting each diffuser port, as well as the pipe, pipe joints, ballast material, and marine life. After completing the south side, the ROV inspected the end structure and then surveyed the north side of the pipe beginning at Diffuser Port #1 and swimming shoreward. The ROV survey on the north side inspected the odd-numbered diffuser ports between 1 and 135, and the south side survey inspected the even-numbered ports between 2 and 136. Pictures of each diffuser port can be found in Appendix C of this report as well as on the ROV video (Appendix A).

The only completely blocked diffuser port was #17 (Photo 3-17). This port has also been

reported as being blocked in all previous inspection reports reviewed by ECO-M. During the ROV inspection, the ROV manipulator was used to poke at the concrete plug at Port #17. The plug moved inward when pushed by the manipulator (Photo 3-18), allowing effluent to flow, but upon release by the manipulator, the concrete plug moved back into place, again stopping any flow. Based on the video, it appears as if this port was drilled, but the concrete plug was not removed. Photos 3-18 and 3-17 show the port flowing and closed, respectively.



Diffuser Port #27 exhibited reduced flow with #27 having less than 10% flow. The ROV

manipulator was used to unclog port #27 with some success. After ramming the port hole a few times with the metal manipulator, the flow increased to approximately 30 to 40%. This was also done during the 2012 survey, and this port returned to its minimal flow sometime between surveys.

Table 3-1, below, lists the conditions found at each of the 136 diffuser ports. None of the

ports appear to be obstructed by encrusting organisms (primarily the anemone Corynactis californica), although these organisms are found around many of the port openings. A few of the ports are located close to or below the upper level of ballast rock (#79), but most have cut a channel in the loose rock by their flow velocity and are considered to be relatively unobstructed. The videography will show these scenarios.

Note: For the video of the north side (odd-numbered) diffuser ports, the ROV started inshore with Port #135 and moved offshore (lower numbers). The audio accompanying the video is correct for Ports 135 – 115. Beginning with Port #113 and continuing through to #1, the audio calls out the name of the diffuser port incorrectly. When the audio says #113, the video is actually of #115. When the audio says #111, the video is actually #113, and so on. 3.4 DEBRIS CLEARING

No abandoned or active lobster pots or other large equipment or debris were seen during the diver or ROV surveys. Lobster pots and balls of fouled fishing line have previously been found and were discussed in previous reports; but none were seen during this inspection. 3.5 CATHODIC PROTECTION (CP)

To evaluate the functional effectiveness of the cathodic protection or CP system, ECO-M divers measured the electrochemical potential of exposed metallic surfaces at the transition zone sealing clamp. The results are in Table 3-2, below. CP measurements were recorded in situ, utilizing dual silver/silver chloride (Ag/AgCl) reference cells. Figure 2-3 illustrates the DC voltage ranges in which some commonly used metals become actively corrosive. Cathodic protection of metallic appurtenances is considered to be attained when these metal surfaces exhibit an electrochemical corrosion potential (ECP) more highly negative than -0.41 VDC at the metal/electrolyte (seawater) interface. If a steel pipe itself is comprised of mild steel, it would be protected when the ECP is more negative than – 0.80 VDC. On a concrete structure such as the Encina outfall, the pipeline itself is not cathodically protected.

ECO-M divers took CP readings on the three zinc anodes exposed along metal portions

of the transition zone sealing clamp, near station 54.00 (Table 3-2). Although they were significantly deteriorated (Photos 2-1, 3-9, and 3-11), they still demonstrated adequate protection (-0.99 to -1.1 VDC). As mentioned in Section 2.7, these zinc anodes are protecting the stainless steel slot covers which conceal a slot in the RCP, which transitions to the larger diameter outfall at this point. The slot covers were placed on the outfall when the old concrete cover was found to be leaking in 1991.



ECO-M divers also took CP readings at some of the manholes, but only as a reference for

the other CP readings. The only metal parts on the manholes seen by our divers were the lift bales. Our divers did not see other metal appurtenances (saddles, tabs, or, injection vents) on the manholes, which are mentioned in a UGI report. These appurtenances were reported on the manholes in the 2008 UGI report and were found to have CP readings between -0.47 and -0.66 VDC at that time. According to UGI’s 2008 inspection report, “the importance of taking readings on the exposed metal such as tabs, saddles, and injection vents is unknown, possibly because the outfall components are not electrically connected to anything. This is not thought to be of structural importance due to the fact that the parts responsible for sealing the outfall are believed encapsulated in the concrete jacket” (UGI, 2008).

3.6 KELP CLEARING

Previous surveys report that giant kelp growth appeared to be limited to depths between roughly 20 and 60 feet. During the present survey, some smaller sub-adult and juvenile kelp plants with fewer than 8 stipes were encountered; these were removed in order to reduce drag on ballast stone and eliminate the potential for rafting of ballast during significant storm events. In this zone of potential kelp occurrence, less than 1% of the hard substrate (ballast rock) was occupied by the giant kelp (Macrocystis pyrifera) from 20 to 60 ft depth.

In addition, there was a dense growth of the feather boa kelp (Egregia menziesii) from

Station 11+50 inshore. The density was such that Manhole 1 was obscured from the videographer. The feather boa kelp around Manhole 1 was removed but the kelp further inshore was not as our divers were forced to vacate the inshore area by a California State Lifeguard. Luckily, feather boa kelp do not have bladders and are thus much less likely to raft ballast rocks away from the pipeline.

3.7 BALLAST LOGGING

The primary protective feature of the outfall pipeline is ballast rock. Armor stones of various sizes were placed along the outfall corridor to protect the pipeline from damage and to restrict its movement in the high-energy nearshore environment. Additionally, placed rock serves as a foundation material beneath the pipe in order to stabilize the seafloor upon which the outfall was constructed. The ballast material in the deeper section of the pipeline (areas around 72-in. pipe) is smaller than the ballast material inshore. This smaller ballast creates a bed on which the pipeline rests and covers approximately the lower one-third of each side of the pipe.

Along each side of the pipe, little or no sorting of the ballast rock was observed along the

outfall corridor; suggesting that the ballast pile is currently in a stable condition with respect to normal oceanographic forces. The ballast around the end structure was much larger than that along the diffuser section of the pipe and the ballast appeared quite stable. Photos 3-1 and 3-5 through 3-8, below, show typical ballast along various portions of the outfall.



3.8 OUTFALL MONUMENTATION

Survey markers were placed at every manhole and every 100 ft between Stations 55+00 and 10+00 and were a useful aid for providing visual positioning for the divers and for the video record filmed during the diver inspection process.

3.9 MANHOLE INSPECTION

The manholes are all located in the shallow sector of the pipeline inspected by the diving teams. Each manhole riser was buoyed off in order to facilitate ready access to the divers in the course of the traverses along the outfall. All manholes were visited, examined, and documented on videotape. All were found to be in good condition. Manhole 1 is located in a zone of heavy kelp growth, which obscured it from videography. Pictures of Manholes 1-6 can be found at the end of this section as well as on the video (Appendix A). On the seaward (west) side of all manholes, 10-15 ft. sections of the top of the outfall pipe are exposed and subject to biofouling.



Table 3-1. Diffuser port inspection results.

Note: Each pipe section has four diffuser points within each section, two on each side

Diffuser Port

ID (in)

Location (side of pipe)

Flow condition Comments

1 3 North Good 170 – ft. water depth 3 3 North Good Ballast has been excavated right in front of

port, good flow 5 3 North Good Reaction tie in place between Port #3 and

#5 7 3 North Good Reaction tie in place between Port #7 and

#9 9 3 North Good 11 3 North Good Reaction tie in place between Port #11 and

#13 13 3 North Good 15 3 North Good Reaction tie no longer attached between

Ports # 15 and #17 17 3 North No flow Port is completely blocked, used clamp to

push on opening which worked while clamp was in place; as soon as ROV clamp removed, plug re-established itself and no flow

19 3 North Good Reaction tie in place between Port #19 and #21

21 3 North Good 23 3 North Good Reaction tie no longer attached between

Ports # 23 and #25 25 3 North Good 27 3 North Limited Port had about 10% flow when inspected,

used manipulator to try and clear, flow increased to 30-40%

29 3 North Good 31 3 North Good Port located near ballast, good flow 33 3 North Good Port located near ballast, good flow 35 3 North Good 37 3 North Good 39 3 North Good 41 3 North Good 43 3 North Good 45 3 North Good 47 3 North Good Port located near ballast, good flow 49 2.75 North Good 51 2.75 North Good 157-ft. water depth



Diffuser Port

ID (in)



53 2.75 North Good 55 2.75 North Good 57 2.75 North Good 59 2.75 North Good 155 – ft. water depth 61 2.75 North Good 63 2.75 North Good 65 2.75 North Good Piece of crab net nearby, not affecting Port

or flow 67 2.75 North Good 69 2.75 North Good 71 2.75 North Good 73 2.75 North Good 75 2.75 North Good 77 2.75 North Good 79 2.75 North Good Port completely obscured by ballast, but

seemed to be flowing well 81 2.75 North Good Port partially obscured in ballast, good

flow 83 2.75 North Good Port located near ballast, good flow 85 2.75 North Good 87 2.75 North Good 89 2.75 North Good 91 2.75 North Good 93 2.50 North Good 95 2.50 North Good 97 2.50 North Good 145 – ft. water depth 99 2.50 North Good 101 2.50 North Good 103 2.50 North Good 105 2.50 North Good 107 2.50 North Good 109 2.50 North Good 111 2.50 North Good 113 2.50 North Good 115 2.50 North Good 117 2.50 North Good 119 2.50 North Good 121 2.50 North Good 123 2.50 North Good Port just above ballast material 125 2.50 North Good 127 2.50 North Good 129 2.50 North Good Anemone growth quite pink in color



Diffuser Port

ID (in)



131 2.50 North Good 133 2.50 North Good 135 2.50 North Good 138 – ft. water depth

Diffuser

Port ID (in)



2 3 South Good 170-ft. water depth 4 3 South Good Port just above ballast, good flow 6 3 South Good 8 3 South Good Port located in ballast, good flow 10 3 South Good 12 3 South Good 14 3 South Good 16 3 South Good 18 3 South Good Effluent flowing at time of flyby, which

clouded picture 20 3 South Good 22 3 South Good 24 3 South Good Port somewhat concealed behind anemone

growth, but good flow 26 3 South Good 28 3 South Good 30 3 South Good Port just above ballast, good flow 32 3 South Good 34 3 South Good 162 – ft. water depth 36 3 South Good 38 3 South Good 40 3 South Good 42 3 South Good 44 3 South Good 46 3 South Good Port has a lot of anemone growth around it,

but good flow 48 3 South Good 50 2.75 South Good 52 2.75 South Good 54 2.75 South Good Port has a lot of anemone growth around it,

but good flow 56 2.75 South Good 58 2.75 South Good 60 2.75 South Good 62 2.75 South Good 64 2.75 South Good



Diffuser Port

ID (in)



66 2.75 South Good 68 2.75 South Good 70 2.75 South Good 156- ft. water depth 72 2.75 South Good 74 2.75 South Good 154 – ft. water depth 76 2.75 South Good 78 2.75 South Good Port has a lot of growth around it, but good

flow 80 2.75 South Good Port just above ballast, good flow 82 2.75 South Good Port has a lot of growth around it, but good

flow 84 2.75 South Good Port just above ballast, good flow, lots of

urchins on pipe in this area 86 2.75 South Good 88 2.75 South Good 90 2.75 South Good 92 2.75 South Good Port has a lot of growth around it, but good

flow 94 2.50 South Good Port located near ballast, but flowing well 96 2.50 South Good 98 2.50 South Good 100 2.50 South Good 102 2.50 South Good 104 2.50 South Good 106 2.50 South Good 108 2.50 South Good 110 2.50 South Good Port has a lot of growth around it, but good

flow 112 2.50 South Good 144-ft. water depth 114 2.50 South Good 116 2.50 South Good 118 2.50 South Good 120 2.50 South Good 122 2.50 South Good 124 2.50 South Good Port has a lot of growth around it, but good

flow 126 2.50 South Good 128 2.50 South Good 130 2.50 South Good 132 2.50 South Good 134 2.50 South Good 136 2.50 South Good 138-ft. water depth



Table 3-2. Cathodic protection readings.

Location Station Previous Reading (Year)

Sep 2012

July 2015 (VDC)

Transition zone – Top Port

(zinc anode) 54+92 -1.00 (2008) -1.0

Transition zone South side of clamp

(zinc anode) 54+92 -1.00 (2008) -1.1

Transition zone South side of clamp

(zinc anode) 54+92 -0.97 (2010) -0.99



Photo 3-1. Encrusted ballast on top of 48-inch pipe section, just east of transition zone.

Note abundant marine growth.

Photo 3-2. 72-inch pipe section just east of diffuser ports. Note lack of marine growth

and lack of concrete spalling (14:42:12 of ROV video).



Photo 3-3. Pipe Joint with intact Reaction Tie between Diffuser Port pipe section and

end gate structure (13:30:37 of ROV video).

Photo 3-4. Pipe Joint with broken Reaction Tie between Diffuser Port #’s 15 and 17

from 2012 survey (17:24:53 of North Side - Video 1).



Photo 3-5. Typical small rock ballast along 72-inch pipe section. Photo near Diffuser

Port #133. (12:33:21 of ROV video).

Photo 3-6. Typical large rock ballast along outfall endgate structure. Large structure in

back is side of endgate (13:30:44 of ROV video).



Photo 3-7. Ballast size change around Outfall End Structure. Ballast around End

Structure is much larger (17:04:12 of South Side – Video 3 - 2012).

Photo 3-8. Typical ballast along 48-inch diameter pipe, near transition zone

(18:14:40 of North Side – Video 2). From 2012 survey.



Photo 3-9. Sealing clamp with deteriorated zinc anodes on 48-inch diameter pipe in

western part of transition zone (00:00:20 of Diver video).

Photo 3-10. Abandoned 48-inch Pipe Cap at east end of transition zone (15:10:03 of ROV

video).



Photo 3-11. Transition zone hardware, where CP readings were taken (00:01:30 of Diver

Video).

Photo 3-12. Outfall End Structure – Looking from south. From 2012 survey. (17:04:30 of

South Side – Video 3).



Photo 3-13. Outfall End Structure – Looking from west. From 2012 survey. (17:05:22 of South Side – Video 3).

Photo 3-14. Slot Cover at west end of Outfall End Structure from 2015 survey. Note absence of effluent coming from bottom end of slot cover.



Photo 3-15. Port on north side of endgate structure, no flow. (13:31:11 of ROV video)

Photo 3-16. Port on south side of endgate structure, no flow. (13:37:06 of ROV video)



Photo 3-17. Diffuser Port #17. (Round circle). It appears this port was drilled but the concrete plug was not removed. (13:15:00 of ROV video)

Photo 3-18. ROV manipulator pushing in on Diffuser Port #17. Note effluent escaping. Plug immediately went back in place upon release by manipulator



Photo 3-19. Beginning of short (approx. 15-ft.) uncovered section of 48-inch pipe just west

(seaward) of Manhole 4. (00:45 of Diver video)

Photo 3-20. Intersection of 48-inch pipe and Manhole 5. (00:42 of Diver video)



OUTFALL MANHOLES

Photo 3-21. Manhole 6 Station 49+72 (00:14:30 in Diver Video).

Photo 3-22. Exposed pipe east of Manhole 6 Station 50+00 (00:13:50 in Diver Video).




Photo 3-24. Exposed Pipe and joint east of Station 42+05 Manhole 5 (00:27:30 in Diver

Video).




Photo 3-26. Exposed Pipe east of Manhole 4 ~Station 34+00 (00:45:22 in Diver Video).




Photo 3-28. Exposed Pipe east of Manhole 3 ~Station 26+00 (00:57:30 in Diver Video).



Photo 3-29. Top of Manhole 2 Station 18+10(01:15:25 in Diver Video).

Photo 3-30. Exposed Pipe east of Manhole 2 ~ Station 18+25(01:15:09 in Diver Video).




Photo 3-32. Exposed Pipe east of Manhole 1 ~ Station 12+25(01:28:53 in Diver Video).



Photo 3-33. Cathodic Protection Reading from transition zone hardware (-0.999 VDC).

Photo 3-34. Cathodic Protection Hardware at 48’ sealing clamp transition to 72’ pipe.



4.0 SUMMARY AND RECOMMENDATIONS

The following points summarize the major findings of this inspection:

1. In general, the Encina Ocean Outfall was found to be in good overall condition.

2. All ballast areas offshore were stable and showed no signs of movement. There appeared to be approximately 10-15% (on average) more ballast piled against the north side of the pipe than on the south side of the pipe, at least in the deeper water areas surveyed by the ROV.

3. All manholes are sound.

4. There is no evidence of scouring along the outfall.

5. 135 of the 136 diffuser ports are open and flowing. Diffuser Port #27 has limited flow.

6. Diffuser Port #17 is still obstructed as has been reported in all previous inspection reports reviewed by ECO-M. It appears that port was drilled but that the concrete plug was never removed.

7. Diffuser Port #27 had reduced flow; this blockage was reduced using the ROV manipulator with some success. Flow increased from less than 10% to approximately 30%.

8. There were no areas of spalling, staining, or concrete cracking determined from this survey; and there was no detected leakage from pipe joints.

9. The outfall End Structure, including the Bulkhead and Scour Pad, appeared to be in good shape overall.

10. The slot cover on the end gate was not leaking, unlike in the 2012 survey

11. Cathodic protection readings of between -0.99 and -1.1 were found along the deteriorating zinc anodes near the sealing clamp in the Transition Zone, demonstrating sufficient cathodic protection.

12. The top of the outfall pipeline is exposed for approximately 15 ft. on the east (seaward) side of each manhole, as well as for a few hundred feet east of Station 12+50.

The following items are recommendations to maintain structural integrity and

environmentally safe operation of the Encina Ocean Outfall. Some of the comments made below were mentioned in previous reports, but are included again because they are still valid points.



4.1 RECOMMENDATIONS

• Continue performing periodic diver/ROV inspections of ballast pile, pipeline, and

diffusers to identify changes that could threaten the structural integrity of the outfall.

• Continue periodic removal of Macrocystis pyrifera and Egregia menziesii (giant and feather boa kelp) along the outfall corridor.

• Perform diver/video “rapid-response” overview inspections after periods of extremely high surf or after significant or very nearby earthquakes, in order to identify damage and potential for failure due to scour, high-velocity currents, or major seafloor movements. These “rapid response” inspections just need to check the structural integrity of the outfall pipe and ballast material and do not need to be as thorough as the periodic outfall inspections such as has just been completed.



5.0 REFERENCES Ecosystems Management Associates Inc. 2012. Encina Wastewater Authority – Year 2013

Ocean Outfall Inspection and Maintenance. December 26. Reference No. 12-04. 38 pp + 5 Appendices.

Pelagos Corporation. 1993. Encina Ocean Outfall 1993 Annual Inspection. December 16, 1993.

8 pp. Pelagos Corporation. 1996. 1995 Annual Inspection of Encina Ocean Outfall. January 1996. 42

pp. Racal Pelagos Inc. 1999. 1998 Annual Inspection of Encina Ocean Outfall. January 1999. 21 pp. Racal Pelagos Inc. 2000. 1999 Annual Inspection of Encina Ocean Outfall. February 2000. 30

pp. Thales GeoSolutions Pacific, Inc. 2002. Year 2001 Annual Inspection of Encina Ocean Outfall.

March 2002. 21 pp. Undersea Graphics, Inc. 2008. Encina Outfall Inspection 2008. September 5, 2008. 35 pp. Undersea Graphics, Inc. 2011. Encina Wastewater Authority Ocean Outfall Inspection 2010.

February 2011. 40 pp.


EcoSystems Management Associates, Inc. A-1 Technical Report ECO-M Reference No. 15-04

APPENDIX A

VIDEO RECORD OF INSPECTION


EcoSystems Management Associates, Inc. A-2 Technical Report ECO-M Reference No. 15-04

APPENDIX A. VIDEO RECORD OF INSPECTION Notes: On ROV videos and still pictures, number in upper left is the local time; number in upper right is date; number in lower left is heading based on magnetic north; and number in the lower right is depth of the ROV. The description (Encina Outfall Endgate) can be ignored. Offshore Video = ROV filmed video Video starts near Manhole 6 and proceeds offshore, around the endgate, and then shoreward, ending near Manhole 5. The north side diffuser ports are filmed east to west, and the south side diffuser ports are filmed east to west. Inshore Video = Diver video Video Starts at Station 54+92 (Slot Cover and Transition Zone) CP Readings on Transition Hardware: 00:00:00-00:03:30 Manhole 6 (Station 49+72): 00:14:30 Manhole 5 (Station 42+05): 00:27:59 Manhole 4 (Station 33+99): 00:45:40 Manhole 3 (Station 25+78): 00:57:38 Manhole 2 (Station 18+10): 01:15:25 Manhole 1 (Station 10+42): 01:31:14


EcoSystems Management Associates, Inc. B-1 Technical Report ECO-M Reference No. 15-04

APPENDIX B

EQUIPMENT USED FOR SURVEYS AND EQUIPMENT SPECIFICATIONS



VESSEL DESCRIPTION 37’ x 12’ Beam all Fiberglass Sportfisher built by UNIFLITE, Inc. 1975 2004 Twin Cummins Marine Diesels 36 mile Radar 1200 Yard Side Scan Sonar Chart Plotter G.P.S. Epirb Two VHF Radios Six Man Automatic Life Raft 6kw Northern Lights Generator Large Bridge with Seating for Five Full Galley with Corian Tops Large Refrigerator & Freezer Watermaker 450 Gallons Per Day Sleeps Six with One Private Stateroom Color TV with VCR & DVD on Directv Satellite Three Live Well Bait Tanks Working Deck Space 10’ x 12’ In 1998 the vessel was redesign and the stern was cut off and added 5.5 feet to the length of the vessel to its present size. Overall length is 42 feet.

Figure B-1. Pacific Venture survey vessel and specifications.



Figure B-2. Seaeye Falcon ROV.



Figure B-3. Seaeye Falcon ROV specifications.



Figure B-4. Trackpoint II Plus Navigation System overview.

Trackpoint II Plus Acoustic Tracking & Navigation System

High Accuracy Data

For over 15 years, ORE’s family of Trackpoint Systems have been providing customers with highly reliable, ultrashort baseline, acoustic tracking data. ORE’s high accuracy Trackpoint II Plus continues this legacy, offering the industry a tremendous value at a reasonable price. The Trackpoint II Plus is the ideal tool for a wide array of subsea navigation and relocation tasks. Target types consist of transponders, responders or free running pingers.

Trackpoint II Plus presents users with a video display of the underwater position of the target or targets relative to a chosen reference point on the surface vessel. In addition to the graphic display of target position, Trackpoint II displays digital values for bearing and range to each target. A standard RS-232 connector outputs position data for each target and allows input of most keypad control functions.

The basic Trackpoint II Plus System consists of:

Model 4410D-01 Command/Display Module Model 4610B Transducer Assembly Model 4110B Interconnect Cable Model 4330B Acoustic Transponder Model 4324C Battery Charger

Features High accuracy; 0.5% slant range Compatible with other industry transponders Data interfaces available for third party

navigation software packages Accepts external analog data from

compasses and pressure sensors ORE’s legendary service to support you

every step of the way

Applications: UUV/AUV Tracking ROV Tracking & Navigation Survey / Towfish Navigation Subsea Structure Relocation Subsea Salvage Operations Diver Navigation Mooring Marking & Relocation Subsea Positioning Depth, Tilt, Heading Telemetry

Trackpoint II Plus Acoustic Tracking & Navigation System

Relative Accuracies Horizontal Position Accuracy 0.5% RMS of slant range (+40 dB signal to noise

ratio) (not including effects of heading, pitch & roll) Slant Range Accuracy 0.5 meter (with known sound velocity) Target Position Repeatability Better than 0.25% RMS of Slant Range Calibrated Accuracy Better than 0.3% RMS of Slant Range System Resolution Range Resolution 0.3 meters Bearing Resolution 0.1° (Better than 0.2% of Slant Range) Receive Available Frequency Bands: 8-14 kHz, 22-30 kHz, 31-37 kHz, 35-45 kHz in 500 Hz

increments Transmit Frequency: 4.5-30 kHz in 500 Hz increments Pulse Width 1-15 ms in 0.1 ms increments Repetition Interval Output Power

1-20 second intervals in 0.1 second increments 500 or 100 watts into 300 ohms

Display Modes and Choices

Individual Target or Ship Centered Modes; Rectangular or Polar Display; North or Ship Referenced Grid Scales – selectable units (meters, feet, yards); Grid Center Offset or Fish Track Mode

External Systems Analog signal for pressure sensor of automatic target depth input Inputs / Outputs Analog compass input to allow North referenced display mode Remote key pulse to

synchronize system to other equipment, +TTL Com 1, RS232C serial data port for system integration and output Com 2, RS232C serial data port for input of NMEA compass heading Remote VRU (pitch/roll) input. Offsets automatically calculated. Isolate transmit trigger output for responder key pulse, (+) TTL or (-) TTL Normal transmit trigger output (-) TTL level pulses for responder key or synchronization to other equipment VGA output to remote monitor

Size: 10.5 in. high x 17.0 in. wide x 20.0 in. deep (26.7 x 43.0 x 51.0 cm) Model 4410D-01

Command/Display Module Weight: 55 lbs. (25 kg)

Size: 25.0 in. long x 6.0 in. diameter (63.0 x 15.0 cm) Model 4610B Hydrophone/VRU Assembly

Weight: 26 lbs. (12 kg)

Size: 24.0 in. long x 2.75 in. diameter (61.0 x 7.0 cm) Model 4211A

Slim Hydrophone Weight: 8 lbs. (3.6 kg)

Size: 15.5 in. long x 13.0 in. wide x 6.0 in. deep (39.4 x 33.0 x 15.2 cm) Model 4740A Amplifier/VRU Weight: 24 lbs. (10.8 kg)

Length: 100 ft. (30m) standard, other lengths available Model 4110B Cable Weight: 35 lbs. (16 kg)

Power Requirements Input Voltages: 97 to 132 / 170-264 VAC, 47-63 Hz, 200 watts Temperature Ranges Command/Display Module: -10 to 55° C operating / -40 to 70° C storage 0-95%

relative humidity, non-condensing Hydrophones: 4 to 40° C operating / -40 to 70° C storage

MAIN OFFICE: 25 Bernard St. Jean Drive, E. Falmouth, MA 02536 Tel. (508)495-6600 - Fax (508)495-6699 - e-mail: [email protected]

HOUSTON: 10450 Stancliff, Suite 115, Houston, TX 77099

Tel. (281)879-7277 - Fax (281)879-9213 - e-mail: [email protected]

Visit us at WWW.ORE.COM



Figure B-5. TSS Meridian Surveyor Gyrocompass overview.



Figure B-6. Trimble Ag GPS 132 overview.



Figure B-7. Hypack Navigation Software overview.



Figure B-7 (cont). Hypack Navigation Software overview.


EcoSystems Management Associates, Inc. C-1 Technical Report ECO-M Reference No. 15-04

APPENDIX C

PHOTOS OF ALL 136 DIFFUSER PORTS



Port 1 Port 2 Port 3 Port 4 Port 5



Port 16 Port 17-blocked Port 18 Port 19 Port 20




Note: Odd numbers represent diffusers on north side of pipe. Even numbers represent diffusers on south side of pipe.














Port not visible-in

ballast?
















Port 136 Note: Odd numbers represent diffusers on north side of pipe. Even numbers represent diffusers on south side of pipe.


EcoSystems Management Associates, Inc. D-1 Technical Report ECO-M Reference No. 15-04

APPENDIX D

PHOTOGRAPHS OF TYPICAL AND SPECIFIC AREAS OF INTEREST OBSERVED DURING SURVEYS



Photo D-1. Station Marker 42+05 – Manhole 5. (00:27 of Diver video).

Photo D-2. Typical marine life covering outfall pipe in western part of 48-inch pipe

section.



Photo D-3. Typical marine life (sea anemones) around diffuser ports. From 2012 survey.

(16:50:09 of South Side – Video 3).

Photo D-4. School of fish above ballast covering 48-inch section of outfall, near Manhole

5 (00:27 of Diver video).



Photo D-5. Rigging the USBL transducer mount before the ROV survey commenced.

Photo D-6. ROV in water. From 2012 survey. Same ROV was used in 2015.

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