DESK TOP STUDY
FOR THE VIRGIN ISLANDS WATER AND POWER AUTHORITY’S
PROPOSED
UTILITY CABLE CONNECTION BETWEEN
EAST END PUERTO RICO AND FREDERIKSTED, ST. CROIX
KRUM BAY, ST. THOMAS AND RED HOOK, ST. THOMAS
PREPARED BY
BIOIMPACT, INC
P.O. BOX 132
KINGSHILL, ST. CROIX
U.S. VIRGIN ISLANDS 00851
APRIL 2011
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Fiber Optical Submarine Cables as Depicted by Alcatel 2010
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iii
Chart Encompassing Project Area
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TABLE OF CONTENTS
page
1
Introduction
General Considerations
2
Climate and Weather
3
Geology and Seismic Considerations
7
Sea Conditions
Tides and Currents
Waves
Water and Seafloor Temperature
11
11
12
13
Environment Considerations
16
Route Selections
Discharges
Navigation Route
18
18
19
Detailed Description of Route
Puerto Yabucoa, Puerto Rico to Frederiksted, St. Croix
20
Permit Requirements
25
Information Needed for Permitting
27
References
29
Appendix A - List of Active Submarine Cables
Appendix B - Latest Charts
http://www.charts.noaa.gov/OnLineViewer/AtlanticCoastViewerTable.shtml
Appendix C – NMFS and FWS Guidance Documents
Appendix D - Obstruction Updates
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INTRODUCTION
Bioimpact, Inc. was contracted on March 7, 2011 to complete an abbreviated Desk Top Study for
the utility cable system being proposed by the Virgin Islands Water and Power Authority. The
purpose of the system is to interconnect the electrical service and provide fiber optic capacity
between Puerto Rico and St. Croix, U.S. Virgin Islands.
The Desk Top Study identifies the most feasible route and landing point between the two islands.
This Desk Top Study includes;
 The available bathymetric charts which depict the maximum sea depth for the proposed
interconnection.
 The environmental conditions along the route including the data on seas, winds and water
quality conditions including maximum ambient temperature in the water column and the
available seabed temperature (near shore section of the route).
 A discussion of areas where near shore cable burial may be permissible and areas where
burial will not be possible due to environmental or geological conditions.
 Available information regarding the variable seabed conditions and topography, including
rocky outcrops, coral reefs, scarp slopes and marine channels and areas of known current.
 The report describes major fishing and shipping activities and anchorages in the vicinity of
each route.
 The report includes the available information on wrecks and dumping areas.
 The report includes the most current information available from the United States Coast
Guard (USCG) in regard to the existing submarine pipelines and cables.
 The report will includes a general discussion of the geology of the routes including a
discussion of faults and earthquakes centers.
 The report identifies all publicly known discharges within the area whether natural or
man-made which might impact the cable routes.
 The report identifies to the greatest extent possible all activities proposed within the cable
corridor which could impact the cable.
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 The report describes in general the Environmental issues associated with the route
including but not limited to coral reefs, endangered species, essential fish habitat and
protected habitats.
 The report includes a detailed listing or all Consents and Permits, both federal and local to
the U.S.V.I. and Puerto Rico which will be required.
GENERAL CONSIDERATIONS
The proposed system spans between Puerto Yabucoa, Puerto Rico and Frederiksted, St. Croix.
There is a trench of significant depth between St. Croix and the northern Virgin Islands. This
trench becomes somewhat shallower between St. Croix and Puerto Rico and by careful routing the
deepest areas of the passage and the areas with the steepest slopes can be avoided. The route
discussed in this survey has been developed by evaluating sea floor depths and conditions,
environmental resources, infrastructure, obstructions (natural and manmade), and permitablility.
Climate and Weather
Prevailing Winds
Puerto Rico and Virgin Islands lie in the “Easterlies” or “Trade Winds” which traverse the
southern part of the “Bermuda High” pressure area, thus the predominant winds are usually from
the east-northeast and east (IRF, 1977). These trade winds vary seasonally (Figure 1) and are
broadly divided into 4 seasonal modes: 1) December to February; 2) March to May; 3) June to
August; and 4) September to November. Below are the characteristics of these modes as taken
from Marine Environments of the Virgin Islands Technical Supplement No. 1 (IRF, 1977).
December – February
During the winter the trade winds reach a maximum and blow with great regularity from the eastnortheast. Wind speeds range from eleven to twenty-one knots about sixty percent of the time in
January. This is a period when the Bermuda High is intensified with only nominal compensation
pressure changes in the Equatorial Trough. The trade winds during this period are interrupted by
“Northerners” or “Christmas Winds” which blow more than twenty knots from a northerly
direction in gusts from one to three days. Such outbreaks average about thirty each year. They are
created by strengthening of high-pressure cells over the North American continent, which, in turn,
allow weak cold fronts to move southeastward over the entire Caribbean region. These storms are
accompanied by intermittent rains, clouds and low visibility.
March - May
During the spring, the trade winds are reduced in speed and blow mainly from the east. Winds
exceed twenty knots only thirteen percent of the time in April. The change in speed and direction
is the result of a decrease of the Equatorial Trough.
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June - August
Trade winds reach a secondary maximum during this period and blow predominantly from the
east to east-southeast. Speeds exceed twenty knots twenty-three percent of the time during July.
The trend for increasing winds results from the strengthening of the Bermuda High and a
concurrent lowering of the pressure in the Equatorial Trough. Trade winds during this period are
interrupted by occasional hurricanes.
September - November
During the fall, winds blow mainly from the east or southeast and speeds reach an annual
minimum. Only seven percent of the winds exceed twenty knots in October. The low wind
speeds result from a decrease in the Equatorial Trough. During this period, especially during late
August through mid-October, the normal trade wind regime is often broken down by easterly
waves, tropical storms and hurricanes.
Storm and Hurricanes
There are numerous disturbances during the year, especially squalls and thunderstorms. These
occur most frequently during the summer, lasting only a few hours and causing no pronounced
change in the trade winds.
A tropical cyclone whose winds exceed 74 miles per hour is termed a hurricane in the northern
hemisphere, and significantly affects the area. These hurricanes occur most frequently between
August and mid-October (Figure 3) with their peak activity occurring in September. The annual
probability of a cyclone is one in sixteen years (Bowden, 1974). The passage of hurricanes are
responsible for damage to coastal structures, grounding of vessels and movement of seafloor
sediments and the burial and exposure of existing cables and pipelines. The 2010 season was a
very active one with numerous storms effecting Puerto Rico and the Virgin Islands.
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Figure 1A: Prevailing Winds, January through June
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Figure 1B. Prevailing Winds, July through December.
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Figure 3. Tropical Hurricane Frequencies in Puerto Rico, and the Virgin Islands (National
Weather Service).
Figure 4. Tropical Storm and Hurricane Occurrences in the Atlantic (National Weather Service)
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GEOLOGY OF PUERTO RICO AND THE VIRGIN ISLANDS
Puerto Rico and the Virgin Islands are near the northeastern corner of the present Caribbean Plate,
a relatively small trapezoidal-shaped plate that is moving eastward relative to the North and South
American continents carried on the American plate. The arc of the Lesser Antilles is an active
volcanic arc above a subduction zone in which the Atlantic oceanic crust of the American Plate is
carried downward under the Caribbean Plate. The closest volcano to the Virgin Islands that is still
active is Saba, about 160 km. to the east.
The Puerto Rican bank which was created by the volcanism during the Cretaceous became
emergent through orogenic movements in the lower Eocene (Meyerhoff, 1933). Sea level has
been variable, and during the Oligocene sea level was 150 meters lower than present day sea level
which made Puerto Rico and the Virgin Islands (less St. Croix) a continuous landmass.
St. Croix is the southern and eastern-most of the U.S. Virgin Islands, lying 40 miles south of St.
Thomas and St. John and separated from the rest of the Virgin Islands by an ocean trench 3,600
meters deep. It is the most easterly possession of the United States and lies about 100 miles southsoutheast of San Juan, Puerto Rico. While St. Thomas, St. John and Water Island are part of the
Puerto Rican geographical bank (the Greater Antilles), St. Croix is geographically located in the
Lesser Antilles and lies completely within the Caribbean Sea.
The narrow coastal shelf surrounding St. Croix descends gradually, allowing for growth of a
fringing reef along most of the shoreline.
The trench between Puerto Rico and St. Croix is not as deep as between St. Croix and St. Thomas
and the sea floor to the southeast of Puerto Rico shallows slightly and it is across this shallower
area the route has been planned.
SEISMIC ACTIVITY
Puerto Rico and U.S. Virgin Islands lie in one of the most earthquake prone areas of the world,
and are susceptible to ground shaking, earthquake-induced ground failures, surface fault ruptures
and tsunamis (tidal waves) (Hays, 1984). The activity is mostly associated with large-scale
tectonic activity or faulting, originating in the Anegada Trough to the northeast of the islands. The
trough and its related scarp apparently were thrown up by block faulting during the late Pliocene
or early Pleistocene. It is oriented generally northeast to southwest, separating St. Croix from
Puerto Rico and the other Virgin Islands. Based on shallow focus earthquakes, the Anegada Fault
Trough is estimated to be more than 400 miles in length. There are indications that strike slip
movement is occurring, with St. Croix shifting northeast relative to Puerto Rico (Puerto Rico
Water Authority 1970). The year 2011 marks the 144th anniversary of the last major earthquake
in the Virgin Islands. This quake, which occurred on November 18, 1867 had an identified
intensity of VIII on the Modified Mercalli Scale. Earthquakes of this magnitude have generally
been associated with epicentral ground accelerations of between 0.05 and 0.35 gravities. Since the
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1867 quake, there has been continuous low intensity activity, all below 6.0 Richter. The last
destructive shock in Puerto Rico was in 1918 (7.5 Mercalli Scale), did not occur along the main
seismic zone, but rather on an intraplate fault near Mona Canyon off the northwest coast. A
possible great earthquake in 1787 (8 to 8.25 Mercalli Scale) appears to have occurred along the
main seismic zone near the Puerto Rico Trench to the north of the island, but data for the event are
scarce. Thousands of tiny earthquakes are encountered every year in the islands. This activity is
associated with the volcanic eruptions that have been occurring to the southeast on the island of
Monserrat.
Seafloor morphology, microearthquakes, and the record of historic earthquakes define a zone of
deformation extending from the Puerto Rico Trench, northeast of the Virgin Islands, trending
southwest along the Anegada Trough and then westerly along the Muertos Trough. The Muertos
Trough is the locus of convergence between the floor of the Caribbean Sea and Puerto Rico.
Maximum dimensions of future large earthquakes are inferred from sizes of blocks in the
Anegada and Muertos Troughs as well as Mona Canyon. Shocks as large as 7.5 Mercalli Scale can
occur on these intraplate faults. Although strain rates on these faults may be an order of magnitude
less than on faults in the Puerto Rico Trench, the large number of potential sources suggest that
damaging earthquakes in this part of the Caribbean can come from either the Puerto Rico Trench
or the intraplate faults with nearly equal probability.
Seismic information from 1990 to 2003 from Puerto Rico Seismic Network is presented below:
2003
During 2003 the PRSN located 947 tremors, which represents a decrease of 2.07%
compared to the previous year (2002, 967 tremors). This level of seismic activity is
considered normal assuming an average of 2 ± 1 tremors daily. Like the previous year, the
month with the most activity was March with a total of 115 tremors (2002, 98 tremors),
while the lowest was January with only 51. Of all the seismic activity, only 26 tremors
(27%) were reported as felt. Of these 26, 2 tremors (May 14 and September 22) were
generated outside of the PRSN, and were located by the NEIC/USGS. The tremor of the
greatest magnitude (6.5 on the Richter scale) occurred on the 22nd of September at
00:45:50 (local time). This tremor was felt throughout the entire Dominican Republic and
in Puerto Rico. It was located 15Km northeast of Puerto Plata and approximately 410Km
northeast of Mayaguez, at latitude 19.847° N and longitude of 70.666° E, with a depth of
10.0 Km. The maximum intensity was VII (Modified Mercalli Scale) in Puerto Plata,
Dominican Republic and V in Puerto Rico . The majority of reported seismic activity this
year ocurred in the southeast region of Puerto Rico, with a total of 9 tremors, followed by
the Virgin Islands platform, which registered 7. The month with the most tremors was
March, with a total of 9.
2002
During 2002 the PRSN located 967 earthquakes, a number exactly equal to the number of
earthquakes in the previous year. Of the total seismicity, only 22 earthquakes (2.2%) were
reported felt. The month of greater seismic activity was March, with a total of 98
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earthquakes, and the one with smallest activity was February with 61 earthquakes. The
earthquake of greatest magnitude (4.7 in the Richter Scale) happened on the 13 of
November at 16:27:49, and was felt in the Virgin Islands and in all Puerto Rico. This
earthquake was located 35 km to the Northeast of Anegada, at the latitude 18.97° N and
the longitude 64.17°W, with a depth of 25.6 km and a maximum intensity of IV (Modified
Mercalli Scale) in Anegada. The earthquake of greatest intensity (V in Modified the
Mercalli Scale, the central area and east of the island) happened on the 20 of June at
11:24:24, and was felt almost all over the island of Puerto Rico. This earthquake was
located in the municipality of Naranjito, latitude 18.244° N and longitude 66.286°W, with
a depth of 6.2 km and a magnitude of 4.0 in the Richter Scale. Most felt earthquake were
concentrated in the Virgin Islands and the Seismic Zone of the Sombrero, although the
month with more felt earthquakes was June. Seismicity was widely distributed this year,
although there were, as usual, greater concentrations in The Sombrero seismic zone and in
southwestern PR. October to November saw the greatest amounts of seismic energy
release.
2001
During the year 2001, 967 seismic events were reported, representing an increase of 30%
relative over the previous rear. The month with the greatest amount of activity was
October with a total of 204 events, while the month with least activity was June with only
51 events. Out of the total seismicity for this year, only 2% were reported as felt (a total of
20 events). The earthquake of October 17 was the event of highest magnitude (5.2 on the
Richter scale) and the most intense (V on the Modified Mercalli scale). The areas with the
highest concentration of seismicity were the Sombrero seismic zone, the area north of
Culebra and Virgin Islands, and the southwest region of Puerto Rico. 54.6% of the total
energy released during this year was released during October in the swarm at the
Sombrero seismic zone.
2000
During year 2000, 735 events were located, representing an increase of 20.2% relative to
the previous year (586 earthquakes in 1999). The month of greatest activity was May with
51 events. Of these, only 2.3% were reported as felt. The earthquake on December 11, was
the event of greatest magnitudes (4.9 Richter Scale) and intensity (IV Modified Mercalli
Scale). The seismicity in the region was quite scattered, although with a greater
concentration in the Island and towards the north, east and west of the local region. Within
the island, the most active region is to the south of an imaginary line that connects Rincón
to Guayama.
1999
Five hundred and eighty six earthquakes were located by the PRSN in 1999. The month of
highest seismic activity was November, with a total of 65 events; the month of lowest
seismicity was April, with 37 earthquakes. Nineteen felt events were reported this year.
Two (February 27th and March 7th) had magnitude of 4.7, the highest for the year. The
strongest felt event was the January 18th earthquake, with a maximum intensity of V on
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the Modified Mercalli Scale. The seismicity for the Puerto Rico region during 1999 was
distributed rather evenly, with a slightly higher concentration of events on the on the
northern, eastern and western portions of this area. Inland, the southwestern part of the
island showed the highest seismic activity.
1998
The PRSN located 622 earthquakes during 1998. There were concentration of earthquakes
north of the Virgin Islands in the Sombrero Seismic Zone, to the north of Puerto Rico,
south of Vieques and within the island, in the south. Thirteen of the earthquakes were felt,
the one of largest magnitude (5.6) occurred December 7 and was located just south of
Anegada, while the earthquake that was felt strongest (MM=V) occurred just offshore of
Manatí on August 28 and had a magnitude of 4.4.
1997
The PRSN located 469 earthquakes in the Puerto Rico region for 1997. Of these events,
only six were reported to have been felt, the largest of which occurred March 31 with a
magnitude of 4.7 and was located in the Eastern Dominican Republic. The earthquake was
felt the strongest took place on July 31 at 10:35 AM and had an intensity of IV on the
Mercalli Modified Scale and was located just north of Arecibo. The PRSN also processed
130 regional earthquakes and 307 teleseismic events
1996
The PRSN located 721 earthquakes in the Puerto Rico region for 1996. Fifteen of these
earthquakes were felt, of these, six were located in southwestern Puerto Rico. The largest
felt event occurred May 10 and had a magnitude of 5.1. The event was felt the strongest
(V MM) was located in Cabo Rojo. The PRSN also processed 114 regional earthquakes
and 418 teleseismic events.
1995
The PRSN located 644 earthquakes in the Puerto Rico region. Seventeen of these
earthquakes were felt; of these, eight were located in southwestern Puerto Rico. The
largest felt event had a magnitude of 4.6 and it's epicenter was located 80 Km north of
Isabela, just east of the mouth of the Mona canyon. No earthquake was reported to have
caused damage, six of the felt events had maximum intensities between IV-V (Mercalli
Modified Scale). The Puerto Rico Seismic Network also processed 149 regional
earthquakes and 348 teleseismic earthquakes.
1994
The PRSN located 816 events in the PR region. Twelve were felt, the largest occurred
September 22 and had a magnitude 5.0. Nevertheless, the one felt more strongly occurred
September 12 in Boqueron, southwestern PR where it had a maximum intensity of V.
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1993
The PRSN located 787 earthquakes in the PR region. Seven events were felt, the largest of
these being one of magnitude 5.0 which occurred in the Muertos Trough southeast of the
island. The Network also processed 127 regional and 248 teleseismic earthquakes.
1992
The PRSN located 678 earthquakes in the Puerto Rico region during 1992. Although the
number of earthquakes located greatly exceeds the earthquakes located in previous years,
they occurred in areas where the greatest seismic activity has taken place historically and
can be related to the oblique subduction of the North American plate under the Caribbean
plate. Only 4 of these earthquakes were felt in the region.
1991
During 1991 there were 364 local earthquakes registered by the network. The largest
concentration of earthquakes occurred on a north-south belt from the Puerto Rico trench to
southern Puerto Rico along longitude 67 W. The seismic network processed 300
teleseismic and 106 regional events.
1990
During 1990 there were 314 local earthquakes registered by the network. The largest
concentration of earthquakes occurred to the northeast of the island. The seismic network
processed 322 teleseismic and 72 regional events.
SEA CONDITIONS
Tides and Currents
Tides in the eastern Caribbean are of low amplitude (on the order of 1 meter or less) as there is an
"amphidromic" point nearby in the central eastern Caribbean around which the tidal wave travels.
At this point, the tidal amplitude is by definition zero. The Caribbean amphidromic point is about
200 km south of Puerto Rico. Tides in the Caribbean are diurnal with one low and one high per
day while tides in the Atlantic are semidiurnal with two lows and two highs per day. Tidal motion
can account for a significant fraction of the total observed current. Tidal currents can be
substantial. Tides are measured at coastal sea-level stations operated by NOAA and the Puerto
Rico Seismic Network.
Observed Data and Graphical Predictions are available for the following stations within the
project area:
9751364 Christiansted Harbor, St Croix, VI
Latitude: 17° 45' N Mean Range: 0.68 ft.
Longitude: 64° 42.3' W Diurnal Range: 0.72 ft.
Established: Feb 10 1981
Present Installation: Feb 8 2006
NOAA Chart #: 25645
Time Meridian: 60 W
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9751401 Lime Tree Bay, St. Croix, VI
Latitude: 17° 41.0' N Mean Range: 0.69 ft.
Longitude: 64° 45.2' W Diurnal Range: 0.71 ft.
Established: Oct 13 1977
Present Installation: Mar 1 1991
NOAA Chart #: 25641
Time Meridian: 60 W
9752235 Culebra, PR
Latitude: 18° 18.0' N Mean Range: 0.78 ft.
Longitude: 65° 18.1' W Diurnal Range: 1.13 ft.
Established: Aug 19 2005
Present Installation: Mar 4 2011
NOAA Chart #: 25653
Time Meridian: 60 W
9752695 Esperanza, Vieques Island, PR
Latitude: 18° 5.6' N Mean Range: 0.69 ft.
Longitude: 65° 28.2' W Diurnal Range: 0.72 ft.
Established: Aug 11 2005
Present Installation: Aug 12 2005
NOAA Chart #: 25664
Time Meridian: 60 W
The surface currents throughout the Caribbean are driven by the North Equatorial Current which
runs through the islands west-northwest and then joins the Gulf Stream (Figure 3). These currents
change very little from season to season with the currents coming more from the south during the
summer months. Because of the shallowness of the Caribbean basin, less than 1000 m, mainly
surface water from the Atlantic flows through the islands. The westerly drift of the Caribbean
current sweeps into the passage between Puerto Rico and the Virgin Islands, currents primarily
flow westerly between Puerto Rico and St. Croix. (Figure 7). According to the prevailing current
map a 0.7 knot current to the northwest is present 46% of the time.
Waves
The deep-water waves off the islands are primarily driven by the northeast trade winds which
blow most of the year (Figure 8). Waves average from one to three feet, from the east, 42% of the
time throughout the year (IRF, 1977). For 0.6% of the time easterly waves reach 12 ft. in height.
The southeasterly swell with waves one to 12 feet high become significant in late summer and fall
when the trade winds blow from the east or when tropical storms and hurricanes pass the islands at
a distance to the south. During the winter months, long length, long period northern swells
develop to a height of one to five feet.
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The USACOE maintains buoys which collect wave direction and height as part of their Wave
Information Study. Buoys L1-3 lies to the southwest of St. Croix, L1-4 lies almost due south and
L1-5 lies to the southeast. Between 1980 and 1999, at station L1-3 the maximum wave recorded
was 8.6 m from 262 (WSW), the maximum wind 24m/s from 38 (NE), and the average wave
was 1.3 m with a standard deviation of 0.4 m. For the same period at station L1-4 the maximum
wave recorded was 10.0 m from 246 (WSW), the maximum wind 27m/s from 210 (SSW), and
the average wave was 1.5 m with a standard deviation of 0.5m. At station L1-5 the maximum
wave recorded was 11.1 m from 222 (SW), the maximum wind 27m/s from 135 (SE), and the
average wave was 1.3 m with a standard deviation of 0.4m. At Station L1-3 January recorded the
greatest wave heights between 1980 and 1999, followed closely by February. At Station L1-4
January recorded the greatest wave heights between 1980 and 1999, followed closely by
December and February. At Station L1-5 December recorded the greatest wave heights between
1980 and 1999, followed closely by January and February.
There are marine forecast buoys available between Puerto Rico and St. Croix which can be
accessed to provide a two day forecast (Oceanweather.com).
Water and Seafloor Temperatures
Water temperatures in the Virgin Islands and Puerto Rico do not change greatly from summer to
winter. In the summer months the water temperature is about 83 degrees and in the winter about
79 degrees. Seafloor temperatures have been found to be equivalent to water temperatures during
Environmental Assessments conducted in the Virgin Islands and during Total Maximum Daily
Load Studies for the Environmental Protection Agency, (Bioimpact, 2009).
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Figure 5. Tidal Predictions for tidal stations in proximity to the cable route.
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Figure 6 Prevailing currents in the Caribbean, IRF 1975. Between St. Croix and Puerto
Rico a 0.7 knot current to the North West is present 46% of the time.
Figure 7. Prevailing current and wave heights April 2011 (Oceanweather, inc.)
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Figure 8. Average sea and swell conditions for Puerto Rico and Virgin Islands Coastal
areas.
AREA WIDE ENVIRONMENTAL CONSIDERATIONS
The marine environment surrounding Puerto Rico and St. Criox is one of the richest
environmentally in the world. The tropical systems support coral reefs, and vast seagrass beds.
These systems support a variety of endangered and threatened species, create essential fish habitat
and are critical for commercial fishing. The warm Caribbean waters are home to endangered sea
turtles, manatees and marine mammals.
Large areas around the Virgin Islands and Puerto Rico, as shown below, have been designated
Critical Habitat for Elkhorn (Acropora palmata) and Staghorn (Acropora cervicornis) corals.
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Figure 9 .Puerto Rico and Associated Islands
Figure 10. St. Croix Area
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As shown in the maps above the cable route will transverse critical habitat for Acropora species at
each end of the route. Acropora are found to depths of 30 meters, and their critical habitat
includes all hard bottom areas with down to that depth. It is fortunate that the water deepens
quickly at each landing site therefore limiting the amount of critical habitat the cable could
potentially encounter. The cable should be routed around critical habitat to the greatest degree
possible, if critical habitat cannot be avoided the cable can be routed around the individual
Acropora species.
Marine Mammal Protection Act
The Antillean Manatee occurs primarily in the shallow water near Fajardo, however it is possible
that manatees may be encountered near the coastline in Puerto Rico. Whales and dolphins are
known to occur throughout the project area. During the placement of the cables adherence to
guidelines to protect these species will be required. National Marine Fisheries and Federal Fish
and Wildlife have developed Standard Manatee Conditions for In-Water Work, Standard Sea
Turtle Conditions for In-Water Work and Standard Marine Mammal Conditions and Guidelines
for In-Water Work (Appendix C). These guidelines lay out special monitoring, and avoidance
measures to ensure the survival of these animals. Sandy Point to the south of the Frederiksted
Landing area is a significant nesting area for Leather Back Turtles.
ROUTE SELECTION
The route selected is the shortest route available while following the basic guidelines set forth by
the U.S. Army Corps of Engineers, avoiding impacts to marine plants and animals where possible
and where impacts are not avoidable minimizing those impacts. The route has been developed to
avoid the deeper areas, as well as shallow areas, obstructions, channels and anchorages.
Discharges
There are no discharges along the route which would have an impact on the cable. There is a
sewer line to the north of the Port of Yabucoa harbor which will require avoidance of the pipeline
if the decision is made to bring the cable in on the northern side of the port.
Fishing Areas
Pot or fish trap fishing is common in the USVI and Puerto Rico. These traps are placed in shallow
waters and may occur on the shallow shelves at either landing. Prior to the cable lay a notice to
fisherman should be published advising them to relocate their traps for the duration of the cable
placement activity. Immediately prior to the lay if traps are still present within the proposed cable
path the traps should be moved as much as necessary to clear the route.
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Navigation Routes
The proposed cable routes are within areas which are frequented by cruise ships, commercial
traffic as well as recreational craft. The Port of Yabucoa lies to the north of the proposed cable
landing area in Puerto Rico, the cable will be land to the south of the channel and should not
impact traffic to and from that port. The Frederiksted Pier lies to the north of the proposed
Frederiksted landing, cruise ship frequent the pier; most ships come from the north and should not
be impacted by any cable laying activities. Lays will need to be coordinated with the Virgin
Islands Port Authority Marine Division, the Department of Planning and Natural Resources,
Division of Environmental Enforcement and the U.S. Coast Guard.
Cable Burial
The burial of submarine cables throughout the region where submerged aquatic vegetation is
present is not looked upon favorably by the permitting agencies. Where inshore sections require
burial mitigative measures must be taken to minimize impact and mitigation is often required.
The cables tend to self-bury over short time periods depending on currents and storm events.
GCN-1 Cable in articulated pipe is buried within 15’ of entering the sand, this self-burial occurred
in less than 2 months (Bioimpact 2006).
The St. Thomas – St. John Power cable has self-buried beneath the seagrass beds.
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DETAILED DESCRIPTION OF ROUTE
PUERTO YABUCOA, PUERTO RICO TO FREDERIKSTED, ST. CROIX
Figure 11. The overall route which avoids the deepest areas of the crossing, the dumping grounds
and sensitive habitats along the route.
The route would originate in Puerto Yabucoa, Puerto Rico. The cable could be landed either to
the south of the main port and channel near PR-9914 or to the north of the port, to the north of a
sewer line which extends approximately 0.5 miles off shore. The cable could be placed on either
side of the 34’ deep channel. The northern side of the channel provides a wider area to lay
between the channel and shallow hardbottom areas which fringe the shoreline. However on the
northern side of the port is Rio Guayanes which supports a mangrove wetland system which could
require wetland permitting and mitigation. While the southern side does have a narrower corridor
it would probably be preferable, but both sides of the port should be investigated. There may be
more suitable landing sites farther south of the Puerto Yabucoa channel however to the south there
are shallow reefs which fringes the shoreline and could be considered critical habitat for acropid
corals. The shelf is relatively narrow and within 1.5 miles the route will be in water deeper than
the designated critical habitat for Acropora and deeper than the habitat areas which will potentially
be designated for 7 additional coral species which are in the process of being placed on the
Endangered Species List (50 CFR Parts 223 and 224).
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Figure 12. The Puerto Yabucoa landing. The yellow lines show two potential routes to either side
of the channel going into the port.
Figure 13. Benthic habitats off of Puerto Yabucoa. The maps show the break in the reef off of the
port and the fringing reefs along the coastline to the north and south.
21
The cable route follows a bearing of 120° True approximately 7 miles before turning to the south
on a bearing of 153° True. The route will stay to the west of the dumping grounds which are
designated on US25640 and to the east of a small seamount. The water depth in this area ranges
from 1600 to 3200 ft. The route will continue to track south passing well south of the dumping
ground. The route will then turn to the east and follow the bottom contours around 5500 ft. The
charts indicate that the seafloor is composed of coral sand. The cable will track to the east and
stay to the north of the navy buoy located off the western end of St. Croix at N17 39.003’ W65
04.301’. Stacin Martin, NAVFAC Atlantic EV31, stated that “With regards to Vieques and any
restricted or potentially hazardous areas your locations are well outside or away from Vieques.
However, you should consult the NOAA charts for other restricted areas (some related to past
military use). The locations provided on the photos are in the vicinity of some of these known
areas, but it is difficult to tell exactly without geographic reference.”
The shelf off Frederiksted is relatively narrow and the route that has been delineated crosses the
shelf at one of the narrowest points. There is a reef at the edge of the slope and there are patch
reefs on the shelf, the route has been sited so that it crosses the reef at its narrowest point and
avoids the scattered patch reefs. The shelf off of Frederiksted is relatively shallow at around 20 ft.
and then there is a steep drop to over 700’ approximately 0.5 miles off shore. A detailed route will
have to be lain across the narrow shelf and reef to ensure that coral impacts are kept to a
minimum. It is very possible when the in-water surveys are conducted that a route that avoids all
coral can be mapped.
Figure 15. The Frederiksted landing, the narrow shelf is clearly visible.
22
Figure 16. The habitats off the Frederiksted landing site. The cable is routed through the area
which has only a narrow band of Reef/Linear Reef.
The route will cross a number of cables as it passes from Puerto Rico to St. Croix, including the
Pan American Cable Segment 1 which is shown below with follows along the shoreline.
23
Figure 17.
Cables originating off the west end of St. Croix (Americas II Cable System, 1999)
Figure 18. The Antilles Crossing Submarine Cable Route showing the St. Thomas-Venezuela 2
cable which was lain in 1980.
It is possible that if necessary the cable could be buried off of Puerto Yabucoa, if seagrass is
encountered mitigation may be required by the permitting agencies. Off of Frederiksted, the near
shore has a hard pavement which may or may not have a shallow sand veneer. Burial would not
be possible in this area, and articulated pipe will probably be required across the pavement.
seagrass impacts.
The deepest depth of the route will be 5600 ft.
24
PERMITTING REQUIREMENTS
Environmental documentation and permit applications will need to be developed and submitted to
the appropriate regulatory agencies with jurisdiction over the coastal waters for the approval of the
placement of the cables.
The entirety of the Puerto Rico to St. Croix cable will rest within territorial waters of the United
States and federal government has jurisdiction over such waters. This jurisdiction is exercised by
various federal agencies:
•
•
•
•
United States Department of Commerce (National Oceanographic and
Atmospheric Administration - NOAA / National Marine Fisheries Services NMFS),
Environmental Protection Agency (EPA),
United States Department of the Interior (Fish and Wildlife Services – FWS)
United States Army Corps of Engineers (COE) as the leading agency in the
process.
The Puerto Rico Landing and surrounding waters are regulated by the following local agencies
and municipalities of Puerto Rico. These agencies primarily have jurisdiction over the land
portion of the cable. These Puerto Rican agencies are:
•
Department of Natural and Environmental Resources (DNER)
•
Planning Board (PB)
•
Environmental Quality Board (EQB)
•
Institute of Puerto Rican Culture (IPRC)
•
State Historic Preservation Office (SHPO)
•
Subaquatic Archaeological Council (SAC)
•
Ports Authority
•
Municipality of Yabucoa
The following territorial government agencies from the US Virgin Islands have jurisdiction over
the St. Croix Landings and cable placements:
•
-
Department of Natural and Environmental Resources (DPNR)
Division of Coastal Zone Management
Division of Environmental Protection
Division of Fish & Wildlife
State Historic Preservation Office (SHPO)
Division of Comprehensive Coastal Planning
•
U. S. Virgin Islands Legislature
Pre-application meetings should be held with both the federal and local agencies of all
jurisdictions noted to present the project and obtain their input.
26
Environmental Documents will need to be prepared and presented to the applicable federal and
local agencies within the respective districts. Given that the USACE San Juan District has
jurisdiction over both Puerto Rico and the Virgin Islands, a single environmental permitting
document encompassing the submarine route is preferred by the COE.
In Puerto Rico, if presented and approved by EPA, there will be no need to present the
environmental document to the EQB. According to the EQB regulation governing the process for
the presentation and evaluation of environmental documents, when a federal agency has complied
with NEPA, then the agency will not have to present another EA before the EQB, if the local
agencies with jurisdiction are consulted during the process of the EA approval under NEPA (Rule
241. B of the EQB regulation).
Once compliance with the National Environmental Policy Act is attained, by means of the
environmental document approval, several endorsements, permits and certifications must be
obtained. These permits and certifications include:
Puerto Rico
•
•
•
•
•
•
•
•

Coastal Zone Management Program Federal Consistency Certificate (Planning
Board),
Water Quality Certificate (EQB),
Consolidated General Permit (EQB),
Concession for the Use of Territorial Waters,
Submerged Lands
Maritime Zone (DNER),
Joint Permit (COE, DNER)
Endorsements from SHPO, IPRC, SAC, the Puerto Rico Ports Authority, and the
Municipality of Fajardo.
Endorsement Institute of Puerto Rican Culture
Notwithstanding that the above will have significant influence on the projects approval process in
the jurisdiction of the Virgin Islands, each project independently will be subject to applicable rules
and regulations set forth in the permitting process governed by the Department of Planning
Natural Resources and the Virgin Islands Legislature.
These approvals include:
•
Coastal Zone Management Major Land and Water Permit
•
Water Quality Certificate
•
Submerged Land Lease
27
INFORMATION NEEDED FOR PERMITTING
1. Bathymetric Study-Including Side scan sonar
2. Magnetometer Study
3. Benthic Assessment
a. Identification of Hard Substrate which is potential acropoid Coral Habitat (and of
nominated species)
b. Identification of Coral Reefs
c. Identification of Seagrass Bed
d. Development of Biological Assessment
e. Identification of Essential Fish Habitat
f. Identification of Significant Species within Habitat type
g. Identification of Potential Impacts and Mitigation Measures
h. Development of Monitoring Plans
4.
Identification of all Existing Cables
a. Identify Owner
b. Active or Inactive
5. Identification of Potential Hazards
a. Naval Areas – unexploded ordinances
b. Sunken Vessels – Modern/Historical
c. Designated Fishing Zones
d. Restricted Zones
e. Dumping Zones
6. Archeological Investigation
a. Submarine along marine route
b. Inland along trenching routes
7. Turtle Monitoring
a. Prior to Installation
b. During Cable Lay
8. Manatee Monitoring
a. Prior to Installation
b. During Cable Lay
9. Survey of Landing Sites
28
REFERENCES
Acatel Submarine Networks, 1998. MAC Submarine Fibre-Optic Cable System, Segment
3, St. Croix – Bermuda, North-UP Sheet 01.
Bioimpact, 2009, Total Daily Maximum Load study conducted under contract to Cadmus
Group, Inc. for the Environmental Protection Agency, East End St. Croix
Bioimpact, 1999, Environmental Assessment Report for te Construction of the Global
Crossing Terminal Station Estate Northside, St. Croix, U.S. Virgin Islands. Submitted to
the Division of Coastal Zone Management, Department of Planning and Natural
Resources.
Bowden, M.J. et. Al., 1969. Climate, water balance and climatic change in the north-west
Virgin Islands. Caribbean Research Institute, CVI,, St. Thomas, Virgin Islands.
Donnelly,T. 1966. Geology of St. Thomas and St. John, U.S. Virgin Islands. In: Hess, H.
(ed.) Caribbean geological investigations. Geol Soc. Amer. Mem. 98:85-176.
Donnelly, T., et al. 1971. Chemical evolution of the igneous rocks of the Eastern West
Indies. In: Donnely, t. (ed.) Caribbean geophysical, tectonic and petrologic studies. Geol.
Soc. Amer. Mem. 130:181-224.
Hays,W.W. 1984. Evaluation of the earthquake-shaking hazard in Puerto Rico and the
Virgin Islands. Paper present at the earthquake hazards in the Virgin Islands Region
Workshop, St. Thomas, April 9-10, 1984.
Island Resources Foundation. 1977. Marine environments of the Virgin Islands.
Technical Supplement No.1 1976. Prepared for the Virgin Islands Planning Office.
Meyerhoff, Howard A. “Physiography of the Virgin Islands, Culebra and Vieques.”
Scientific Survey of Puerto Rico and Virgin Islands, (New York Academy of
Sciences), Vol. IV, Pt. I, pp. 71-141.
Multer, H.G. and L.C. Gerhard (ed.) 1980. Guidebook to the geology and ecology of
some marine and terrestrial environments, St. Croix, U.S. Virgin Islands, Spec. Publ. No.
5 West Indies Laboratory.
TYCO Submarine Systems, Ltd, 1998, PAC Cable Network System, DeskTop Study
Charts, Grover Beach, California to Butler Bay, St Croix, Chart 19.
TYCO Submarine Systems, Ltd., 1999, Americas II Cable System, St. Croix Cable
Installation Segments A, B, and C. Method of Procedures.
29
Whetten, J.T. Field Guide to the Geology of St. Croix, U.S. Virgin Islands,” In: Multer, G.
and L.C. Gerhard (editors), Geology - Ecology of St. Croix, U.S.V.I. Special Publication
No. 5, West Indies Laboratory, Fairleigh Dickenson University, U.S.V.I. 1974.
30
APPENDIX A
APPENDIX B
List of Latest Charts and obstructions
http://www.charts.noaa.gov/OnLineViewer/AtlanticCoastViewerTable.shtml
APPENDIX C
APPENDIX D