ENVIRONMENTAL IMPACT ASSESSMENT

OF PROPOSED MODIFICATIONS TO

GALLOWS BAY COMMERCIAL HARBOR FACILITIES

ST. CROIX} U.S. VIRGIN ISLANDS

SUBMITTED TO

VIRGIN ISLANDS PORT AUTHORITY

SUBMITTED BY

THE ISLAND RESOURCES FOUNDATION Post Office Box 4187

St. Thomas, U.S. Virgin Islands 00801

PREPARED BY

DAVIDA. OLSEN} PH.D.} PROJECT DIRECTOR 1 EDWARD L. TOWLE} PH. D.} RESOURCE PLANNER 1 GEORGE F. TYSON} JR.} HISTORIAN1 DENNIS K. HUBBARD} PH.D.} SEDIMENTARY GEOLOGISl

June 1978

1 Island Resources Foundation, St. Thomas, Virgin Islands

2 West Indies Laboratory, Fairleigh Dickinson University, St. Croix, Virgin Islands

TABLE OF CONTENTS

Acknowledgements i

Executive Summary ii

1. 00 PROJECT DESPRIPTION 1 1. 01 General Description and Purpose 1 1. 02 Location of the Project 1 1. 03 Engineering Description of the Project 1 1. 04 Mitigating Plans for Construction and Operation 1 1. 05 Relationship to Other Facilities 1

2.00 ENVmONMJii}NT-AL.SETT~ENS:WITH8B'J;'THE PROJECT 6 2.01 Landform 6 2.02 Drainage 6 2.03 Geology and Soils 7 2.04 Seabed 7 2.05 Water Resources 8 2.06 Potable Water Resources 8 2.07" Oceanography 8 2.08 Tides 11 2.09 Wave Impact 11 2. 10 Marine Water Quality 13 2. 11 Living Resources 13 2.12 Rare and Endangered Species 13 2. 13 Marine Ecology 15 2. 14 Climate and Weather 19 2. 15 Rainfall 22 2. 16 Air Quality 23

3.00 RELATI0.NSHIP-OFFTHE PROPOSED PROJ'ECT 23 TO. hAND, USE PLANS

4.00 PROBABLE1rIMPAC'FOF THE PROJECT 25 4.01 Topographic Impact 25 4.02 Drainage 25 4.03 Impact on the Marine Environment 26 4.04 Erosion 26 4.05 Fresh Water Resources 26 4.06 Potable Water 26 4.07 Impact on Existing Wate rways 26 4.08 Water Turbidity and Sedimentation 27 4.09 Terrestrial Vegetation 27

T ABLE OF CONTENTS (continued)

4.10 Endangered Species 27 4. 11 Atmospheric Impact 28 4. 12 Impact on Historical and ArchaeologicalResources 28 4. 13 Visual Impact 28 4. 14 Recreational Use 28 4. 15 Positive and Arne liorative Effects 28

5.00 POTENTIAL ADVERSE EFFECTS WHICH CANNOT 29 BE AVOIDED

6.00 ALTERNATIVES TO THE PROPOSED ACTION 29

7.00 RELATIONSHIP BETWEEN LOCAL SHORT-TERM 29 USES OF MAN'S ENVm.oNMENT AND ENHANCEMENT OF WNG-TERM PRODUCTIVITY

8.00 m.REVERSIBLE OR IRRETRIEVABLE COMMITMENTS 30 OF RESOURCES WHICH WOULD RESULT FROM PRO-JECT IMPLEMENTATION

8.01 Natural Resources 30

APPENDIX I: Currents In Gallows Bay 31

APPENDIX II: Sediments of Gallows Bay 38

APPENDIX III: History and Archaeo logy of 64 Gallows Bay

LITERATURE CITED 77

Table I. Table II. Table III. Table IV.

Figure 1-3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8

LIST OF TABLES

Summary of Water Quality Parameters Terrestrial Vegetation Fish A 19ae and Mo lluscs of Ga llows Bay Average Monthly R.ainfall

LIST OF FIGUR.ES

Engineering Drawings of Project Currents on Incoming Tide Currents on Falling Tide Areas of Similar Current Velocity Biological Associations in Gallows Bay Location of Benthic Transects

14 16 20-21 24

3-5 9

10 12 17 18

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ACKNOWLEDGEMENTS

The present effort was greatly facilitated by the cooperation of the staff of the Virgin Islands Port Authority, Gallows Bay facility. Mr. Claude Berry, Gallows Bay Port Captain, supplied much of the information and drawings. R.onald Tutein and R.oberto Incarnacion skillfully operated the boats during the current study. John Woods, Virgin Islands Port Authority Special Projects Director, assisted in many ways. Thanks are also due to Ms. Kathy Finnerty and Ms. Judith Towle for typing and editorial review of the document,respectively.

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EXECUTIVE SUMMARY

An environmental assessment of the proposed modifications to the Gallows Bay commercial harbor facility was undertaken'from mid-May to mid­June, 1978. The modifications include clam shell 'dredging of approx­imately 7,500 cubic yards of terrestrial sediments which have been de­posited in the northeast corner of the bay during flood conditions in the past decade. The dredged material is to be deposited behind a 273 foot sheet pile bulkhead to provide additional parking for container shipping and additional vesse 1 dockage and offLoading facilities. The major anti­cipated impact on the marine environment will be increased turbidity during the actual construction. The observed currents lack sufficient velocity to transport suspended sediments of the particle sizes observed out of the bay. Local marine environmental impact is expected to be confined to the Gallows Bay commercial area.

The Gallows Bay area is subject to occasional heavy flooding. A review of available historical information indicates that much of the present day commercial port facility is situated on the site of a previously filled in shallow pond area. This modification, which took place between 1794 and 1856, probably significantly reduced the natural ability of the land­form to absorb runoff. The project, as designed, requires an extension and redirection of the existing concrete runoff channel, but we do not anticipate that this modification will alter its effectiveness during times of normal flooding.

The major impacts of the project will be confined to increased noise levels during construction and then, subsequent to construction, when an anticipated increased cargo load will pass through Christiansted's already congested streets. This latter problem should be resolved as plans are underway to establish a major commercial port on the south shore of St'~ Croix and to develop the GaLLows Bay area as a recreational boating center. The proposed modifications will enhance the use of the area as a recreational facility.

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GALLOWS BAY ENVIR.ONMENTAL IMPACT ASSESSMENT

1. 00 PROJECT DESCHIPTION

1. 01 GENEHAL DESCHIPTION AND PURPOSE. The Port Authority of the U. S. Virgin Islands plans to dredge the northeast segment of the exist­ing Gallows Bay commercial harbor facility (using a clam shell dredge) to remove 7,500 cubic yards of essentially terrestrial sediments from a 0.31 acre borrow area and deposit the spoil behind a 273 linear foot sheet steel piling bulkhead. It also proposes to construct an extension of the existing flood control ditch and expand (by approximately 0.67 acres) the existing parking facility for container ship roll-on/roll-off trucks. The new facility will also provide additional storage for contain­er cargo and increase the available bulkhead for unloading vesse ls by approximately 25 percent. The project appears to be completely consis­tant with current usage of the area and to offer no serious environmental problem.

1. 02 LOCATION OF THE PROJECT. The project is to be located on the site indicated (see engineering drawing Figure 1) in Gallows Bay, Christian­sted, St. Croix, U. S. Virgin Is lands.

1. 03 ENGINEEHING DESCHIPTION OF THE PHOJECT. The engineering drawings of the project, furnished by the Virgin Islands Port Authority, are shown in Figures 1 - 3. They diagram the construction of the fac­ility in an area of Gallows Bay which is presently the site of a delta of terrestrial debris and sediments at the head of the existing drainage control ditch. This ditch currently crosses the existing port facility parking area.

1. 04 MITIGATING PLANS FOR CONSTHUCTION AND OPERATION. The proposed use of clam shell dredging techniques and &JQth,s'edim,ent; filters in the actual construction should significantly reduce the release of fine sediments into the area. The Port Authority will also attempt to complete the construction operation expeditiously in order to reduce noise, dust, and smell in the region of the project. This attempt is being made since, in Gallows Bay, light industry (zoned W-3) immediate ly abuts medium residential land (zoned H-3).

1. 05 HELATIONSHIP TO OTHEH FACILITIES. The proposed bulkhead does not extend beyond the present boundaries of the Port Authority land holdings at Gallows Bay. The parcel immediately adjacent to the south is government owned and is currently used as a site of operations for approximately 30 local fishing boats, some anchored and some pulled

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Figures 1, 2, and 3. Engineering plans for port modifications at Gallows Bay, Christiansted, St. Croix, U. S. Virgin Islands. The proposed project involves construction of a 273 linear foot sheet piling bulkhead, c lam shell dredg­ing of 7,500 cubic yards of essentially terrigenous sediments and debris from a 0.31 acre borrow area and deposition of the spoil in 0.67 acre spoil area. The project will create new bulkhead facilities and storage area for containerized, roll-on/roll-off truck borne cargo.

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up on shore. There is also considerable use of this parce 1 and the Port Authority facilities on weekends by recreational and quasi-commercial fishermen. The parcel immediately to the north of the Port Authority holdings is owned by St. Croix Marine Development and is operated as a boatyard and marina. The new facilities will enable the Gallows Bay Harbor to handle anticipated increased small vessel shipping traffic in the future. The land to the east is owned by a variety of private indivi­duals and embraces both residential and commercial properties. At present the facility appears to be handling traffic at about full capacity. The new facilities may lead to increased commercial traffic within Gal­lows Bay, and this may slightly reduce the available space for commer­cial/recreational fishing boat moorings that are currently located with­in the area of the Port Authority submerged lands holdings. Fort Christ­ianvaern and the Christiansted National Historic Site at the far southwest corner of the bay will not be impacted by the project. The Christiansted harbor area was developed under U. S. Department of the Interior Blan­ket Permit No.7. During construction, there will be a temporary in­crease in noise and dust which will end with project completion. The main effect of the project upon adjacent facilities will be coincident with the ability of the Port facilities to handle minor increases in shipping and roll-on/roll-off truck traffic until such time as alternative facilities are deve loped elsewhere, probably at the proposed south St. Croix Port fac­ility as is currently being planned and negotiated.

2.00 ENVIRONMENTAL SETTING WITHOUT THE PROJECT

2. 01 LANDFORM. The Gallows Bay area is situated in a flood plaing,rea.Qf low reW~f immediately to the southeast of Mt. Welcome. Whetten (1974) shows that the underlying formations are primarily recent alluvium and are made up of beach sand, beach rock, and stream deposits. A review of the available historical information (see Appendix III) reveals that much of the Gallows Bay area was originally a pond or mangrove lagoon. Between 1780 and 1856 this area was filled in, forming the site of the present Gallows Bay light industrial zone. Presently much of the overly­ing sediments in the area of the commercial harbor facility are dredged marine sediments whose composition is described from a series of cores collected prior to the 1963 construction of the harbor facility. There is an additional terrestrial sedimentary component which has been carried down the flood control ditch in 1974 and again in October of 1977.

2.02 DRAINAGE. The entire Gallows Bay area is part of a large tidal plain which extends from the eastern side of Mt. We lcome west through the town of Christiansted itse If (Corps of Engineers Report, 1975). There

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has been considerable flooding in 1974 and again in October 1977. On both occasions considerable terrestrial sediment and debris was carried into the bay. This terrestrial input has resulted in a shallowing of the northeast corner of the harbor from a dredged depth of 16 feet to a cur­rent average of 4 to 6 feet. There is also an extensive "delta" of ter­restrial sediments and debris at the mouth of the flood control ditch. This flood control ditch was apparently constructed along the course of an existing stream or drainage channel, originating in the mountains near Lang Observatory which is shown in nineteenth century maps of the area. It is apparent, from a review of historical information, the Corps of Engineers reports and interviews with knowledgeable persons regard­ing the question of flooding in the area, that the flood control channel is inadequate to handle the unusually heavy rainfalls which do occur, however infrequently.

2.03 GEOLOGY AND SOILS. The water shed adjacent to the Gallows Bay area is underlain by three geologic formations, the previously described alluv­ium and beach deposits, tuffacious formations and the Caledonia formation (Whetton, 1974). The soils in the Gallows Bay area are Jaucaus sand and Isaac gravelly clay loam. The soils of the watershed area are Cramer grave lly clay loam, Levallee grave lly c lay loam, Made land, and San Anton clay loam (R.ivera, et. al., 1970).

2.04 SEABED. The seabed and sedimentary geology of Christiansted harbor have been extensively investigated by Nichols, et. al. (1972). Our infor­mation on Gallows Bay sediments comes from aseries of 13 surface and near surface sediment samples taken as part of this study. The results (shown in Appendix II) indicate a rather uniform sediment distribution. The sediments are poorly sorted and most (consistently over 50 percent) are in the fine sand range (0.625 to o. 125 mm). Some researchers fee 1 that sediments in this range should be considered as mud. Transport of sediments of this particle size requires currents in the range of 0.24 to 0.32 m/ sec. As noted in the present study (section 2.07), the highest current observed within the Gallows Bay commercial facility was O. 1 m/ sec., and transport out of the bay area will probably be associated with heavy ship traffic. Suspension of the sediments can be accomplished by currents as low as O. 17 m/ sec., and our results would indicate that currents in this range may occur within Gallows Bay at times of maxi­mum tidal flow and at times when water transport overfuorlg~ R.eef from wind and storms is greatest. In general, however, the impact of the pro­ject can be expected to be re lative ly restricted to the area of Ga Hows Bay. The sedimentary analysis revealed that most of the sediments with­in the bay are of terre strial origin and are carried into the bay as runoff from rain storms. Further, it is suggested that the blueish material in the finer sediments originates from the cretaceous volcanic material oo::!urring in the Christiansted area.

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2.05 WATER RESOURCES. The Gallows Bay flood control ditch was apparently constructed along the source of a stream bed. As recently as 1961 the Praeger and Cavanaugh survey for the original harbor project showed standing water in the stream bed (and on the site of the current harbor warehouse facilities). There is little available contemporary informa­tion on the groundwater resources of the region except for a report by Robison (1972) who implies that there are insignificant groundwater re­sources outside of the central portion of St. Croix.

2.06 POTABLE WATER RESOURCES. Potable water in the area is primarily from the government distribution system and captured rainwater. Robison (1972) implies that there are no significant groundwater resources in the area. The current project should not have any impact on the water re­sources of the area.

2.07 OCEANOGRAPHY. The oceanography of Christiansted harbor has been investigated by Jacobsen (1951), Dong (1972), and Nichols, et. ale (1972) with respect to the current patterns. These reports describeda counter­clockwise current system whereby the wave and wind driven water moves through the harbor and out the channe 1. Jacobsen reported a clockwise current on an incoming tide which was not found by Nichols, et. ale Dur­ing the intervening years between the two studies, the harbor underwent extensive dredging which increased the volume of the harbor by 14 percent (Nichols, et. al., 1972). This change in volume may have accounted for the differences in observed currents. The only available current informa­tion for Gallows Bay and the eastern portion of Christiansted harbor comes from Jacobsen (1951), who shows that the general flow in this portion is clockwise on both tidal states and continues from the Altona lagoon area until it joins the east flowing current from the western portion of the bay at the channel between Protestant Cay and St. Croix~ Jacobsen does not show current velocities. His effort, therefore, cannot be used to predict transport of suspended fines from the dredging proposed by the present project.

In an effort to predict sediment transport. we undertook, in the present study, to determine current ve locity and direction in greater detail. The methodology used is described in Appendix I, and the results of that effort indicate that current flow through the Gallows Bay area is, as predicted, a clockwise current system on both the incoming (Figure 4) and outgoing tides (Figure 5). During incoming tidal conditions, the observed cur­rents had a stronger souther ly component. Water entered the commer­cial harbor through the cargo dock and proceeded in a clockwise direction.

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FIGURE 4. Current direction during an incoming tide results in a clock":' wise current system. The dashed line represents an inferred current direction.

Protestant Cay

Gall ows Bay

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--10-

FIGUHE 5. Current direction during falling tidal conditions in the Gallows Bay area moves in a clockwise direction. The dotted lines are from Nichols, et. ale (1972); the solid lines from drogue and die measurementswere taken from May 19 to May 22, 1978, and the dashed lines are inferred directions.

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Gallows Bay I,

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During outgoing tides there is a strong shift to the west as water begins leaving the bay at the head of the commercial dock. The highest ve locity was measured at this point (0. 1 m/ sec). Current ve locity to the east of a line drawn between the cargo dock and St. Croix averaged 0.03 m/ sec on both incoming tides (N=14) and outgoing tides (N=13). Outside of this line the currents average O. 05 m/ sec average of both tides (N=14).

When a chart was prepared showing contour lines around areas of sim­ilar current velocity (Figure 6), we found that there were three areas of extremely low current (less than 0.02 m/ sec) where heavy deposition of suspended fine sediments can be expected. Two of these areas (in the head of the bay (B) and off the end of the cargo dock) are also exposed periodically to heavy turbulence from prope llor wash originating with commercial shipping in the Gallows Bay area. Diving observations of these areas revealed Little resuspendable sediment. The third of these areas (A in Figure 6) is outside the region of effect from shipping traffic and contained significant amounts of sediment.

Currents in Gallows Bay travel in a clockwise direction. Observed cur­rent velocities were beneath the threshold required to transport the fine sediments out of the bay. We expect that occasional currents enter the bay with sufficient velocity to suspend the fine sediments. Suspension and transport of some of the fine sediments may occur associated with turbulence re suIting from shipping and boat wake s. The impact from sediment suspension will be concentrated within the area of Gallows Bay and along the shore line towards Fort Christianvaern.

2.08 TIDES. Tides in Christiansted harbor agree closely with the predictions for Galveston, Texas (Nichols, et. al., 1972) except that the time of high water is 9 hours and 17 minutes ear lier and the heights are lower than at Galveston by a factor of 0.57. The maximum tidal range was from O. 7 feet to -0. 1 foot. The average tidal range during the measurements was O. 7 feet.

2.09 WAVE IMPACT. The Gallows Bay area, due to its position in the east­ern portion of the bay, is protected from all normal sea conditions. At­lantic groundswells, which are an important factor in shoreline develop­ment in the northern Virgin Islands, are more or less blocked by these islands and are not significant factors in St. Croix. Long R.eef lies along the seaward edge of Christiansted harbor and stops wave energy from reaching the shore. The only potential source of wave damage is from hurricane waves which are most like ly to occur between July 25 and Oct­ober 25. The Corps of Engineers (1975) study estimates that a severe

Current Velocity (M/sec.)

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FIGUR.E 6, The contour. lines enclose areas where similar current velocities were measured during the present study. Areas of low velocity were observed at points A, B, and D. Area D was observed near the end of a tidal cycle and is possibly an artifact. Suspended fines generated by clam shell dredging at site C are likely to be deposited at A and B but are likely to be carried outside the harbor once they reach the acce lerating current system that enters Gallows Bay.

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hurricane, with an expected probability of one in a hundred years, will raise tidal levels at Gallows Bay by five feet. This would permit a great­er portion of storm driven wave energy to enter the harbor. There have been 24 hurricanes which passed within a fifty mite radius of the Virgin Islands since 1900 (Bowden, 1974).

2.10 MAR.INE WATER QUALITY. A summary of the Department of Conserva­tion and Cultural Affairs water quality data from the Gallows Bay area is listed in Table 1. It is apparent from the various literature sources that the area has been continually stressed since at least the time when the pond area was filled in. Removal of this pond eliminated a natural "filterll for terrestrial sediments and created a situation whereby they were carried directly into the Gallows Bay area. Jacobsen (1951) reported that the waters in the area of the abbatoir were depressed in dissolved oxygen and had significant numbers of fecal coliform bacteria. Indeed, some of his sample s were unacceptab le by current minimum water quality standards. Jacobsen reported that the waters of Gallows Bay away from the abbatoir did not show any signs of po llution apart from increased tur­bidity. Subsequent measurement of the waters had shown the increased turbidity and suspended solids to be a permanent feature of the area. Other parameters indicative of water quality perturbations have not in­dicated that the area is under eutrophic stress to any greater degree than much of Christiansted harbor. Water quality must certainly be highly altered during times of flooding, however, as it is apparent that much of Christiansted's 7.25 km2 watershed drains into Gallows Bay.

2. 11 LIVING RESOURCES. The terrestrial living resources are remnants of the extensive shoreline mangrove and "Kasha" forests shown in the 1961 Praeger and Cavanaugh survey which preceeded the original Gallows Bay project. At present there is a single remnant of the Kasha (Acacia tortuosa) and nine surviving white mangroves (Laguncularia racemosa). The other surviving trees are found within the project area and are listed in Table II. The ground cover is made up of a variety of grasses and sea purslane (Philoxerus vermicularis). The avifauna in the project area is extremely sparse. We observed two pigeons (Columba sp. ) feeding on the shoreline. Several frigate birds (Frigata magnificans) were ob­served feeding on discarded fish that had washed up on the shore. Sev­eral species of anolid lizards (Anolis sp. ) were also observed.

2.12 RARE AND ENDANGERED SPECIES. A single hawksbill turtle (Eretmochelys imbricata) was observed on two occasions within the commercial harbor. The diet of the hawksbill includes both animal and vegetable food (Rebel, 1974). Among the animal components of the diet are oysters, barnacles, sponges, ecotprocts and other fouling organisms which are common on

TABLE 1. SUMMARY OF WATER QUALITY PARAMETERS IN THE AREA OF GALLOWS BAY, ST. CROIX, U. S. VIRGIN ISLANDS

Parameter Year b c 1951 a c c (units) 1971 1975(3) 1976(10) 1977(5 )

Temperature (oc) 25 28.7 26.9 24.5

Salinity (ppt) 35.7 35.6 36. 1

D. O. (mg/1) 5.2/ 6.0 6.4 6.5 6.3

pH 8.2 8.4 8.2

Turbidity (FTU) .30 1. 04 1.2

Secchi Depth (M) <2 3. 1 2. 7 2.3

Fecal Col. (cells/100m) 92/0 1-64 1 18 31

Suspended Solids (mg/L) 5-10 mg/L

Sources: a Jacobsen (1951). Two stations: Near slaughter house / in Gallows Bay. Data collected in August 1951. b Nichols. et. a1. (1972). Data colle cted June to September 1971. c Data furnished by V.1. Department of Conservation and Cultural Affairs. Mean values are given, sample

size in parenthesis.

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the bulkhead and pilings of the commercial harbor, and we presume the turtle may have been attracted to the harbor for feeding purposes.

The brown pelican (Pelecanus occidentalis) may also utilize the Gallows Bay area for feeding purposes, although none were observed. Despite the fact that it is cited as endangered (U. S. Department of the Interior, 1974), the brown pelican is common throughout the Virgin Islands and nests successfully on various offshore rocks and cays and remote coastal areas.

The St. Croix ground lizard, Ameiva polops, which is on the Enpangered Species lis~ is only found on Protestant Cay and Green Cay and therefore will not be affected by the proposed harbor modifications.

2.13 MAHINE ECOLOGY. The distribution of the major benthic community types is shown in Figure 7. The extremely heavy sedimentation caused by terrestrial sediment input from runoff and continual resuspension of these sediments by shipping traffic has severe ly limited biotic deve lop­ment in the area. Indeed, attached algal growth is limited to the shaLLow­er portions of the dredged basin and to the intertidcilflats. An attempt to quantitatively sample the benthic community was abandoned when the first 7 quadrats landed on areas which could not be adequate ly coLLected. Sub­sequently. the benthic community map shown in Figure 7 was developed from a series of SCUBA and waded transects (shown in Figure 8).

The sublittoral community is roughly defined by the extent of the turning basin. The dominant algal forms are a fine filamentous blue-green (Schizothrix sp. ) and the Chlorophycean algae Bryopsis sp. and Cladophora sp. The latter two forms and non-attached detrital algae. which are extremely abundant outside the area. may have been transported into the turning basin from outside. They are concentrated in wash channels near the end of the cargo dock. The ichthyofauna of the area is confined to areas where depos­ition of debris has created habitat for juvenile fishes. We observed tarpon (megalops atlanticus) and mackeral (Scombroremorus sp. ) feeding on fry (Anchoa sp. ).

Visibility was limited to a maximum of two meters during the SCUBA transects, and we expect that the species list in Table II may omit a number of the species present. The shallower water at the edge of the turning basin permits greater light penetration, and there is a consequent increase in the diversity of the subtidal she If. The most common form was Gracilaria cylindrica and several occurrences of turtle grass (Thalassia testudineum). Generally this "community" must be considered as a

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TABLE II. Terrestrial vegetation in the project area was dominated by a variety of grasses, Sea Purslane (Philoxerus vermicularis) and the trees listed be low.

Common Name Scientific Name Abundance

Portia tree Thespesia populnea 8 trees Wild Cotton Gossypium barbadense 2 trees White Mangrove Laguncu.laria racemosa 9 trees Kasha, Acacia tortuosa 1 bush Gum Arabic Acacia nilotica 4 bushes Surinam Calliandra Calliandra surinamensis 1 tree

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Intertidal Shelf

tx"1l Subt idal Shelf ~

E4 Turning

100 200

SCALE IN FEET

6 42' FIGURE 7. Distribution of the three "community associations" within the

Gallows Bay area. There is a fourth association of species found in and around the piers and bulkheads.

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GALLOI,)S BAY

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SCALE IN FEET

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transitional zone between the extreme ly impoverished turning basin and the slightly richer intertidal flat. There are occasional patches of Halophila baiUonis in the she If area. Halophila appears frequently in areas where there is heavy siltation and/ or substrate instability. A small barracuda (Sphyraena barracuda) was observed feeding on small fry (Anchoa sp. ) in this area. Many gobies and blennies were observed but not specifically identified along the shelf edge and in the intertidal.

The intertidal region in Gallows Bay contains large areas of fine sediments of probable terrestrial origin. Most of the benthic growth occurs on rocks and debris that extend above the sediments. The intertidal zone has been extended inland since there has been considerable shoreline erosion since the original dredging. The intertidal contains a much greater diversity of attached algae. Enteromorpha flexuosa, a green algae whic:h grows in turbid waters and has a high phosphate metbolism (Becking and MacKay, 1956), is abundant. Its presence is indicative of possible eutrophic in­fluences in the area. A variety of other algae are common.

The final biotic association in the are a is found on the pilings and bulkheads of the commercial facilities. Table III indicates a similarity between this and the intertidal community. Ectocarpus sp. is the dominant algal form and is an inconspicuous element of the intertidal community. There is also a conspicuous sponge and ectoproct fauna on the pilings. The area at the base of the bulkheads and particularly the pilings is the site of the richest icthyofauna in the area. A number of snappers were observed, among them the grey snapper (Lutjanus griseus), schoolmaster (L. apodus), dog­tooth (L. jocu) and virgin snapper (L. analis). Virgin snappers were a considerable element of the catch orapproximately 15 recreational fisher­men that used the pier over the weekend. The grapsid crab Sesarma ricordi was common at the airwater interface on the pilings and bulkheads, and the dominant fish was the tomtate (Haemulon aurolineatum).

2.14 CLIMATE AND WEATHER.. The Virgin Islands extend eastward from Puerto R.ico directly in the be It of subtropical, easterly trade winds. The climate is maritime tropical and is characterized by generally fair weather, steady winds and slight but regular seasonal and diurnal ranges of temperature.

The formation of the climate is a direct result of five important elements: the geographic location of the islands; the small size of the islands; their elongated narrow sha~;their steep hilly topography; and the situation of the islands in an extensive warm water body. These five elements are

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TABLE III. Fish. algae and molluscs found within the GaLLows Bay area. He lative abundances are shown as Present but not Abundant (P), Common (C) or Dominant (D).

Subtidal Turning Fish Intertidal Pilings ~shelf Basin Common Name Scientific name

Barracuda Sphyraena barracuda Tarpon Megalops atlanticus Sprat Harengula clupeola

H. humeralis Anchovy Anchoa sp. Squirre l fish MyrIPristis jacobus Mullet Mugil curema Mackeral Scombroremorus sp. Schoolmaster Lutjanus apodus Grey snapper .!:.:. griseus Dogtooth L. jocu Virgin snapper L. analis Yellowtail Ocyurus chrysurus Tomtate Haemulon aurolineatum

Blenniidae sp. Porkfish Anis6tr~mi1Svirginicus Porgy Calamus sp. Pufferfish Diodonholacanthus Butterfly fish Chaetodon capistratus Beau Gregory Eupomacentrus leucostictus Bicolor damse lfish E .. partitus Doctorfish Acanthurus chirurgus

A. coerulus

Molluscs Cerithium sp. Cymatian vespaceum2 Bulla occidentalis C antharus tinctus Natica canrena

Algae Hhodophyceae

Ceramium sp. Dasya cr011~m;na

C

C

P

P

P C

P P C P C D C C P

C C C C C

P

C C

P

P

P P P P P P

D P

C P

P P P

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Subtidal Turning TABLE III (cont. ) Intertidal Pilings shelf Basin

Gyninogongrus griffithsiae D D Gyninogongrus sp. P HypIlea musciformis C P Gradiaria. cylindrica C Grate 16upia filidna .. C C D Acanthaphora spicifera C C Gala~allra squallda P P SpYrldia filamentosa P

Phaeophyceae Dictyota d1v,:aricata C P Ectocarpus sp. D P P PocockielJavariagata C Padina sanctae -crucis P

Chlorophyceae Halimeda incrassata P Bryopsis sp. 1 C D Bryopsis sp. 2 P Ud:itea flabe llum P Enteromorpha flexuosa C P Chaetomorpha graculis C Cladophora sp. 1 P C Cladophora sp. 2 C D Caulerpa mexicana C C C P C. verticitlata P P

Cyanophyceae Schizothrix D

Spermatophyta Halophilabainonis P only at ed Thallassia testudineum P

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responsible for producing the particular types of precipitation, temper­ature, winds, cloud cover, evaporation and humidify which, taken to­gether, produce the climate.

Variations in temperature between the coolest and the warmest months range from 5 to 7 degrees. The highest temperatures are in August and the lowest in January or February. The temperature seldom drops be­low 70 degrees or rises above 90 degrees.

Regularity in the direction of the trade winds is one of the most depend­able weather phenomena in the islands. Almost without exception, the trade winds blow from an easterly direction. The general range in wind velocity is 5 to 15 miles per hour with daily variations. A velocity of more than 15 miles per hour occurs more frequently in winter than in other seasons. Leeward slopes are protected against the full force of the trade winds, but the flow is strong to pass over the higher terrain without diminishing in ve locity.

The islands are affected occasionally by tropical storms and hurricanes. They lie outside the main paths of severe tropical disturbances except those that occur from August through the first half of October. The storms that deve lop over the South Atlantic east of the Antilles chain usually move toward the north or northwest and pass north or south of the islands; rarely do they pass directly over them. There is a risk of hurricane force winds about once every eighteen years.

The steady flow of trade winds and the warm temperature result in high evaporation rates. Open-pan water measurements taken on St. Croix indicate rates (72.69') that exceed the average annual rainfall.

The average relative humidity varies from a high of 90 during the early morning hours in October and November to a low of 63 in the early after­noons of February and March.

2.15 RAINFALL. Climatological and meteorological records for the island of St. Croix and specifically the Gallows Bay area extend back well into the eighteenth century and have been summarized and interpreted in Stone (1942), Bowden (1968), and Zube (1968).

Precipitation occurs primarily as short and limited, but frequent showers. The showers are a direct result of orographic lifting over the islands' steep hills. Variations in elevation, the form of the islands, their size, and the prevailing easterlies cause different parts of the islands to have

-23-

varied annual amounts of fainfall, with the higher elevations receiving greater amounts. St. Croix displays the effect of orographic lifting and prevailing winds on rainfall more readily, with the island's northwest corner receiving in excess of 50 inches per year, while the easterly por­tions of the island get as little as 20 inches per year.

Monthly rainfall averages for the Christiansted and Gallows Bay area based on all prior data have been calculated and mapped by Bowden (1968) and are cited in Table IV. The annual average faUs between a low of 33 inches and a high of 47 inches with September, October, and November being the wettest months. These averages can however be misleading as localized storms and rainfall can and have produced precipitation leve Is (at Fort Christianvaern) in excess of 14 inches within a 48 hour period, as on 7 and 8 October of 1977, when major coastal flooding, erosion and runoff problems were especially severe in the area east of Christiansted including Gallows Bay and Altona Lagoon. The October, 1977 monthly rainfall total at the Christiansted Fort rain gauge station was 19.08 inches and the annual total for 1977 was 50. 78 inches, obviously an extremely unusual circumstance occuring on the average of about once every fifteen years since 1852.

2. 16 AIH Q.UALITY. According to published reports by the Government of the Virgin Islands, Department of Conservation and Cultural Affairs, all nat­ional ambient air standards are maintained on St. Croix, and the Gallows Bay area, as a light industry commercial zone, has no serious air quality problems.

Present roll-on/roll-off trailer truck traffic moving from dock to storage/ parking areas and nearby warehouses stirs up some ephemeral road dust and produces engine exhaust fumes, each of which may increase slightly as a consequence of incremental additional activity resulting from the proposed improvement to the existing port facility. Within the general area of the project, other non-project sources of continuing minor air pollution are the AntiUes Gas facility, well to the south, and the St. Croix Marine Deve lopment, bordering the Port Authority facility to the north.

No Significant increase in air pollution is anticipated from the construction phase of the proposed project.

3.00 HELATIONSHIP OF THE PHOPOSED PHOJECT TO LAND USE PLANS. The nature of the project is in keeping with the commercial nature of the area. The area is zoned for commercial use, and the project is an attempt to remedy and facilitate maintenance of the harbor area as we II as to create additional operational bulkheading for unloading and storage

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TABLE IV. Average Monthly Rainfall (in inches) for Gallows Bay, St. Croix area and adjacent watershed.

January 2-3 February 1-2 March 1-2 April 2-3 May 3-4 June 3-4 July 3-4 August 3-4 September 4-5 October 4-6 November 4-6 December . '3-4 .

totals 33 47

Average low annual total - 33 inches Average high annual total -47 inches

From: Bowden. M. J •• Water Balance of a Dry Island, The Hydroclimatology of SL Croix, VirginIslandsand Potential for Agricul­tural and Urban GroWth. Dartmouth University. 1968.

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for roll-on/roll-off shipping. The parking ,lot is nearly on the site desig­nated for a projected warehouse in the 1961 Praeger and Cavanaugh survey. Changes in shipping technology in the intervening years have led to the use of parking lots and container cargo as warehouse s. Zoning of the area for light industry and its current use as a commercial harbor are consistant with the projected project. Currently the beach front area to the south of the project site is used by local residents as a bathing and picnic area and by fishermen and small boat owners as a mooring area. None; of these use patterns will be seriously impacted by the project.

A detailed planning study carried out by Madigan and Praeger in 1974. regarding a port facility development for St. Croix. recommended various improvements at the project site in Gallows Bay which are compatible with the proposed modifications to the existing Gallows Bay port facility. In effect. the eventual construction of a major heavy cargo facility on the south coast of St. Croix as PJwposed in Madigan and Praeger's report and currently under discussion by the Port Authority would enable the modified Gallows Bay area to more readily be converted to small boat recreational use. This ultimate possibility is also compatible with plans currently being proposed by the Virgin Islands Planning Office (Coastal Zone Management Program) for a small recreational/fishing boat dock/ pier and possibly a boat launching ramp in the southern portion of Gallows Bay, heavily used by local small boats as mentioned above.

4.00 PROBABLE IMPACT OF THE PROJECT.

4.01 TOPOGRAPHIC IMPACT. Some topographic changes will result from the site deve lopment as the entire area of the project will be raised to three feet above mean low water including a nine inch concrete pad.

4. 02 DRAINAGE. Diversion of the flood control canal through ninety degrees will have some slight effect on drainage in the area, but the canal has been demonstrated to be ineffective during heavy rains. The entire Gallows Bay area is a major flood plain and the present pattern of flooding under conditions of heavy rainfall probab ly commenced when the Little Pond was filled in. Clogging of the canal will be prevented through installation of steel access grating and regular clearing. The project will not affect groundwater in the area since the available information indicates that there is no fgttoundwa.fer in the vicinity.

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4.03 IMPACT ON THE MAHINE ENVIHONMENT. The project will alter the Gallows Bay seabed configuration only insofar as to restore the original dredged depth which has been progressive ly lost as a result of terriginous sediment deposition. Currents in the area are low and should not affect any of the proposed structures. The major scouring and erosive forces in the area appear to stem from terrestrially originating flooding and boat wakes from the substantial fishing community in the area. Another scouring force from larger shipping in the turning basin appears to mainly affect the m,icl.' portions of the basin and lead to deposition at the pheriphery of the basin.

4.04 EHOSION. Shoreline stability in the area is a problem. The original Corps of Engineers study (described in a December 29, 1948, letter from the Secretary of the Army to the Congress of the United States) did not anticipate the affect of the dredged turning basin as a potential energy sump for the shoreline sand and sediments. Consequently, there has been considerable shoreline erosion. This process will not be adversely effected by the current project except that terrestrial sediments and debris will be diverted from the head of Gallows Bay (where they have created a considerable delta and filled in the turning basin) to the more southerly portion of the bay. It is possible that the project may redirect these sediments in such a way as to furnish material for a reconsolidation of the shoreline. It is more likely that the terrigeneous material will simply be put into the turning basin at a different point.

4.05 FR.ESHvWA'llBRIRESOURGEB. "The fresh water resources of the area will not be affected. The original circulation pattern apparently resulted in standing water in what is now the warehouse area of the commercial fac­ility. The gut that is now represented by the flood control ditch was shown on eighteenth century charts of the area as a channe 1 linking the sea to a small lagoon behind the southeast corner of the bay and in nineteenth cen­tury maps as a stream that originated in the mountains near Lang Observ­atory. Currently it is generally dry. There are no suspected ground­water resources. A Public Works alternate sewage pumping station offers a greater threat of groundwater contamination than the present project.

4.06 POTABLE WATEH. The project will have no impact on localized potable water supplies as all local water is either caught in cisterns\.or carried in the public water distribution system.

4.07 IMPACT ON EXISTING WATEHWAYS. The project represents maintenance of an existing waterway. Original approval of the 16 foot commercial har­bor facility carried with:!it the assumption that the harbor would either be stable or be permitted reasonable maintenance. The project increases the efficiency of the Gallows Bay area, thereby slightly reducing pressures for alternative deve lopment.

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4.08 WATER TURBIDITY AND SEDIMENTATION. Increased turbidity can be expected during the course of the project. The currents in the area are slight and much of the suspended sediment can be expected to settle in the area of the turning basin itse If. The fine sediments that are suspended during dredging operations and later resuspended as a result of shipping will either re settle in the area or will enter a regime of acce lerating cur­rent velocities which will carry them out of the harbor mouth. We do not expect there to be any areas within Christiansted harbor where there will be secondary deposition of sediments. The current pattern observed from the present study and Nichols, et. ale (1972) d:es1:trJt indicate that any of the sediments will be carried into the southern or western portions of the bay. A southern element of the current system during rising tidal conditions was observed by Jacobsen (1951) but has not been subsequently observed. The harbor volume has increased by 14 percent as a result of dredging between 1951 and 1972 which may have qualitatively changed the circulation pattern. If this southern element of the current persists, then the sediment plume may be carried in the direction of the town of Christiansted. Deposition during periods of slack tides may be expected to occur along the plume path.

4.09 TERRESTRIAL VEGETATION. The project will eliminate the surviving coverage along the shoreline of small scrub and trees. No avifaunal use of this habitat was observed during the study period. The only use ob­served of the area by birds was associated with discarded fish. The pro­ject should not significantly alter a suspected use by brown pe licans which

vvere not observed during the study period.

4. 10 ENDANGERED SPECIES. The single occurrence of a hawksbill turtle in an area of such heavy use by commercial shipping and fishing boats is indeed remarkab leo Since benthic cover by algae is extreme ly sparse, it is possible that the turtle's activities involved feeding on the fouling organisms on the pilings and bulkheads. The project will create addition­al bulkheading (therefore food). It is unlikely that the turtle was in the harbor for reproductive purposes since tl::ere is no useable shore line at present for egg laying and Rainey (1976) does not record any nesting act­ivities within Christiansted harbor during recent history. A more likely explanation for the occurrence of the turtles would be that it was an ir­regular visitor to the Gallows Bay area. The project would not affect any attractive (to the turtle) aspects re levant to the habitat.

The other federally endangered species which we suspect to be an occas­ional visitor to the Gallows Bay area is the brown pe lican. A Ithough we did not observe pelicans in the area, we suspect that they feed on bait

-28-

fish at times. The project should not permanently cause any changes in food abundance for brown belicans in Gallows Bay.

4.11 ATMOSPHERIC IMPACT. We cannot foresee the project affecting atmos­pheric phenomena on any significant scale. However, modification of the localized microclimate may result. The parking lot for the container cargo will reflect and/ or absorb heat during the day and radiate it at night. Because of the open coastal location and almost constant breezes, thermal changes resulting from the development should not seriously affect local mete oro logical conditions.

4. 12 IMPACT ON HISTORICAL AND ARCHAEOLOGICAL RESOURCES. There are no surviving sites in the project area. The old abattoir. and the ruins of the Mount Welcome windmill along the eastern shore were demolished in the 1960's to make way for the new port facilities. Pottery, china and bottle fragments, some dating from the eighteenth and nineteenth century, can be found along the shoreline immediately to the west of the project area, but as they are clearly exogenous rather than autochthonous, we do not feel that they represent a significant historical/archaeological resource. As the area to be filled in consists of fill previously taken from the harbor, no marine archaeological site is imperiled by the project.

4. 13 VISUAL IMPACT. Visually, the project will modify the area only insofar as it will extend the available area of parking. The loss of remaining fol­iage will reduce the attractiveness of the area somewhat. The project will replace the present delta of terrestrial debris and sediments with a commercial facility. From the view of the commercial interests, the project will improve the visual aspects of the area by replacing a poorly utilized area, filled with debris, by one which is commercially useful and efficient.

4. 14 RECREATIONAL USE. Use of the beachfront area to the southwest of the project by bathers, picnickers and boaters will not be seriously im­pacted by the project. Existing usable beach area will not be diminished, and only a small reduction in the mooring area will result. The project area is not being utilized as a swimming, picnicking or mooring area.

4. 15 POSITIVE AND AM~LIORATIVE EFFECTS. Positive and arne liorative effects center around increasing the efficiency of the are a for its desig­nated purpose - - commercial shipping. They inc lude increased bulkhead for loading and unloading, increased storage for container cargo, and maintenance dredging to the design depth in that portion of the bay. Other possible ameliorative effects may result from the diversion of the flood

-29-

control waterway in that the terrestrial sediments may furnish material for and retard the ongoing shoreline erosion process. By increasing the efficiency of the harbor area, the project will enable the continuance of traditional West Indian trade connections with other islands in the Lesser Antilles, the island of St. Croix may achieve better goods and services, and there will be a slight reduction in efforts to deve lop other sites for commercial harbors.

5. 00 POTENTIAL ADVERSE EFFECTS WHICH CANNOT BE AVOIDED. There will be some loss of shoreline vegetation. Fine sediments will be suspended and eventually carried out the harbor mouth. Increased harbor facilities may lead to increased usage and therefore increased truck traffic in the area. There will be increased noise from the dredging operations and from increased shipping activity. A slight reduction in the mooring area for fishing boats may occur. During the project there may be some slight hydrogen sulfide smell from dredged sediments.

6.00 ALTERNATIVES TO 'IDHE PRDPOSED ACTION. A no action alternative is the only one explored. This is not acceptable since the status quo is resulting in a gradual shallowing of the head of the harbor area and, therefore, reduction in the ability of the commercial harbor to function efficiently in meeting the shipping needs of the is land. No action also increases the pressure for development of alternative harbor facilities since the popuLation of St. Croix is faced with a·near absolute dependence upon imported goods and supplies.

7.00 RELATIONSHIP BETWEEN LOCAL SHORT-TERM USES OF MAN'S ENVIRONMENT AND ENHANCEMENT OF LONG-TERM PRODUCTIVITY. The project results from the absolute requirement to import goods, through shipping, to meet the needs of the people of St. Croix. Since this is simply a maintenance modification of an existing facility, it is consistant with the long term needs and requirements of the island. Indeed, since the need for warehousing facilities was planned 17 years ago, there has been ample time to critically analyze the necessity for the structure. If proposed deve lopment of port facilities on the sbuth shore of St. Croix takes place, then the project will enhance the projected use of Gallows Bay as a recreational boating facility.

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8. 00 ill.REVERSIBLE OR ill.RETRIEVABLE COMMITMENTS OF RESOURCES WHICH WOULD RESULT FROM PROJECT IMPLEMENTATION. The project will create an area of concrete parking for roll-on/roll-off ship­ping where an area of terrigenous sedimentation, heavily disturbed inter­tidal, accumulated fine sediments currently exists. The bulkhead, fill and concrete parking area will replace an area which bears little relation­ship to the area before the original dredging project. The use of the fac­ility may increase the volume of traffic, but the zoning within the area indicates that such changes have been planned for. The decimation of the vegetation will signal the completion of the shore line changes started with the original pfpject initiation.

8.01 NATURAL RESOURCES. No local natural resources will be irreplace­ably consumed. The sediments to be dredged are primarily terrestrial in origin and overlie the dredged bottom so that no truly natural commun­ities are being destroyed. Human resources, such as labor and finances, will be irretrievably spent but in exchange for resources and hopefully impr0vement of logistical operations within the area.

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APPENDIX I

CURRENTS IN GALLOWS BAY

INTRODUC TION The currents in the area of Gallows Bay were described in 1951 by Jacobsen as part of a general study of Virgin Islands harbors with respect to sew-age disposal. His findings describe the flow in GaLlows Bay as a clock-wise current system which proceeds west from the bay until it joined the prevailing current system of Christiansted harbor. This greater system was described by Jacobsen as being a clockwise system during incoming tides and counterclockwise during outgoing tides. The next study of Christiansted's currents was completed in 1972 by Nichols, et. al. Nichols did not find the clockwise incoming tide current system reportedby Jacobsen but carried out extensive studies and reported current speeds throughout much of the bay. He may have accounted for the absence of the clockwise current system as he report ed that in the intervening years dredging act­ivities had increased the volume of the harbor by around 14 percent. He did not study the currents of GaLlows Bay. The absence of contemporary information on the velocity of water currents in GaLlows Bay led to the present study since the suspension of fine sediments from the dredging operations and their subsequent resettlement can be expected to have the greatest environmental significance.

MATERIALS AND METHODS Current was measured throughout Gallows Bay and the waters to the west of the commercial harbor through the use of current drogues and dye. The drogues were set to travel at 1m depth. Nichols found that current was greatest near the surface, and since we are concerned with how far the sediments may be carried, we decided to measure near-surface cur­rents. We also released fluoroscene dye from fixed stations along the piers and from anchored buoys offshore. When there was a clearly defined edge to the dye distribution, we measured velocity; otherwise dye markers were used as an indication of direction. At each measurement, we loc­ated the boat at the position of the drogue or dye marker and recorded the direction to fixed landmarks on shore with a handbearing compass., When the results were plotted, the distances trave led and times were used to calculate the current ve locity and distance.

RESULTS The results of this study are shown in Appendix I, Figures 1, 2, 3, 4, and 5. They indicate that the currents in the bay flow in a clockwise direction during both incoming and outgoing tides. The currents within

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the bay averaged O. 03 m/ sec (average of aU 27 measurements and 0.05 m/ sec outside of the commercial harbor). When a chart was prepared showing contour lines around areas of similar current velocity (Figure 3), it indicated that there were three areas of extremely low current (less than 0.02 m/ sec) where heavy deposition of suspended fine sediments is to be expected. Two of these areas (in the head of the bay and off the end of the cargo dock) are exposed to heavy turbulence from prope llor wash originating with commercial shipping in Gallows Bay. Diving observa­tions of these areas revealed little resuspendable sediment. The third of these areas is outside the region of effect from shipping traffic and contained significant amounts of sediment.

The current is affected by tidal variation and by wind driven water input across the reef. The character of the tide at Christiansted is like that at Galveston, Texas. except that the time of high water is 9 hours and 17 minutes earlier and heights are lower than at Galveston by a factor of 0.57. This similarity has been verified by Nichols, et. al. (1972). The average tidal flow in the study period was O. 7 feet. Winds during the study period ranged from 15 to 25 knots.

CO~LUSION

Currents in Gallows Bay travel in a clockwise direction at very low vel­ocities. Much of the suspended sediment from"i1he project will remain in the area of the bay itself until gradual resuspension by boating and ship­ping traffic carries it from the bay. Those sediments which are carried from the bay will be carried into increasing current ve locitie s and will probably be transported out of the harbor before settling. The impact from sediment suspension will be concentrated within the area of Gallows Bay and along the shoreline towards Fort Christianvaern.

If areas of similar current ve locity are enc losed by contour line s (Figure 5). the results can be used to predict the disposition of the suspended fine s. The project is being undertaken in an area of minimum velocity. Velocity increases slightly to the south of the project area, and there are depos­itional (areas of lowered current ve locity) off the end of the cargo dock and along the shoreline towards Fort Christianvaern. The low velocity area at point C may be a result of a series of measurements which were taken late in the tidal cycle when the tide was slackening. The deposition­al basin at the end of the cargo dock is also an area where there is much turbulence and resuspension of sediments from large vesse 1 prop wash. Diving observations support the prediction that sediment is not trapped here.

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APPENDIX I, Figure 1. Current direction during an incoming tide results in a clockwise current system.

Protestant Cay

Gallows Bay

( i

D 100 200 ..... MiitE It¥t.{i#f¥M¥¥Bf¥i¥ti?iRiUBii ....

Scale (in feet

-34-

o~ . .

GALLm·}S BAY

~ I

64 42'

o - 100 200 'w

SCALE iN FEET

I-<

(/')

f­U w ~ o IX 0...

APPENDIX I, Figure 2. Drogue and dye paths on incoming tides during the study period. Ve locity in (m/ sec) is shown, when calculated, at the mid point of the interval.

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APPENDIX I, Figure 3. Current direction during falling tidal conditions in the Ga Hows Bay area move S in a clockwise direction. The dotted lines are from Nichols, et. at. (1972); the solid tines are from drogue anddye measurements taken from May 19 to May 22, 1978, and the dashed tines are inferred directions.

Protestant Cay

/ I

/

/t

Gallows Bay

I,

()

. /.::"

100 200

-Sea 1 e '( i nfeet

-36-

GALLOHS BAY

"'/

o -•

64 42'

100 200

SCALE IN FEET

l­t..)

W 'J o 0:: c...

APPENDIX I, Figure 4. Drogue and dye paths on-outgoing tides during the study period. Ve Locity (in m/sec) is shown, when caLcuLated. at the mid point of the interval.

Current Velocity (M/sec.)

- - -<0.02 - - -..;. - 0.02- 0 .04 ~ 0.04-0.06 .. ·· ... ·.·u 0.06-0.08

>0.08

GALLDl'·JS BAY

· · · · ·

, .

.... ....

-37-

......... , .... •••• It

.' .'

"!', ,.- ••••• .. .'", '" I. ".. to ' ........ ..

.... . ,-

64 42'

o' " " .' .. '

: . ,.'

0"

",

100 20Q

SCALE IN FEET

APPENDIX I. Figure 5, The contour lines enclose areas where similar current velocities were ffi'eal81l1ned during the present study. Areas of low

l­t..) w ~ o n:: CL

ve locity were observed at 13eiri1s A;Bj ""ahd D. Area D was observed near the end of a tidal cycle and is possibly an artifact. Suspended fines generated by clam shell dredging at site C are likely to be deposited at A and B, but are likely to be carried outside the harbor once they reach the accelerating current

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APPENDIX II.

SEDIMENTS OF GALWWS BAY

by

Dennis K. Hubbard, Ph. D. West Indies Laboratory

Fairleigh Dickinson University St. Croix, U. S. Virgin Is lands

-39-

TECHNIQUES

A total of 13 surface and near-surface sediment samples were

taken in the Gallows Bay project area. The location of each core

is given in Figure 1. Samples were taken in two ways. Surface

samples were taken with a 5 cm X 20 cm core tube. Where preliminary

probings of the bottom revealed lenses of varying materials, a longer

(40+ cm) core was taken. The core was divided visually into repre­

sentative sections and samples were extracted from each section of

core.

Twelve of the samples were analyzed to determine the graphic

mean and inclusive standard deviation of Folk (1974). Samples were

first wet seived through 3.0~(0.125 mm), 4.09 (0.0625 mm) and 4.5¢

(0.044 mm) screens to determine the amount of fine sand and mud

contained in the sample. These portions of the sample were then

dried and weighed. This preliminary wet seiving step was added to

the analysis to prevent caking of the rest of the sample upon over

drying. Without this step, the coarser grains can form aggregates,

bound by the finer grains. If this occurs, any further analysis

is invalid.

The rest of the sample was dried at 110 0 F in an oven to remove

water from the sample. Each sample was then seived at 1/2 ~ intervals

between -l~ (2.00 mm) and 3.09> (0.125 mm). The results of the> 31

and <:. 3¢ analyses were combined for each sample, and the relative

percentages of the various grain sizes in each sample were computed.

Cumulative frequency curves (Figs. 2-13) were constructed and used

-40-

APPENDIX II, Figure 1. Base map showing sample locations. Map is not to scale. See Appendix II, Table III for further information.

'.

'. . . ,

, .

'.

to-o

CD o

".'. "

• I

'. · . , o· · .' . , .

· . · . · ,. · .

~------------------------~ .. , . · " L-____________________________ ~. •

an • (Q

o

, . , ,

I •

t' I • · , . ,'.

· . · ,

" .

~------------------~ "

~ , - - ... ... OQ , .....

J

I

I ~ d , ..... ,

, . .. ,... .. ~ .... '. .

...

)- ". d '

2 ::'

~

o · a.. ' .. " · . " , .

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' I II I, " .• "" , +ffi U-lL_ -f-+tt- .--L:' '-'. ----0--- : ++h-:--I_; __ :Ij::.r~;_, til! ::r !~1+H+:::J::1~H= I ':,:-ib:t:::j"~±r ffin Hn"-t-l"fc:i1-: wlrm :)- f'H!+I+j:h~r+i t4 ~- "99 99.8 99.9 "" III' !.!-t-·~;r' "I : t--'j, !_,~: I,i.'

0.05 0.1 O.L 0.:' 2 5 10 20 30 40 50 60

Cum 0/1'\

I fl::>. co I

Cumulative frequency curves for Gallows Bay samples. 99.99 99.9 99.8 99 98

o

~

'&..N

Ifl

~

-Em, :mLI-----t-OC I " -;J -+---r- - '-'4 1111

I I i

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--..;;;

0.0, 0.05 0.1 0.2 0.5 2

95

I I

: !

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If1-++ ! Ii I

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I I

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40 50

Note that the vertica 1 dimension is a probability plot. 40 30

'--j-T

60 70

01

20

~m1t +il±if-80

10

90

5 2

95 98

I I

I I

i i f

I I

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0.5 0.2 0.1 0.05

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o.ot b> '"d '"d t?;j Z t:I ~ t-I t-I .. Ij:j 1-'-

(Tq ~ 1-$ (J)

J-l J-l

U)

~

t:;:J I

6' rr

99.99

I OJ o

Cumulative frequency curves for Gallows Bay samples. 99.99 99.9 99.8

I -

E-1,,-1 il:! L+-+ -l--t-·~ T-;--:

H=J:P" t I L. ___ L...L,' -,' ,~ .::J...-r---r- : I:~ __ .! _ !

; I

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Note that the vertical dimension is a probability plot.

40 30 20 10 5 2 0.5 0.2

I j

IT iT

11

, I

LUI I1I11 I I I

t-H

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0/

0.1 0.05

rn-f

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c.f)

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I 01 1-& I

'Q

Cumulative frequency durves for Gallows Bay samples. Note that the vertical dimension, is a probability plot.

99.99 99.9 99.8 99 98 95 90 80 70 60 50 40 30 20 10 5 2 0.5 0.2 0.1 0.05 0.01

I -o

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~±t-t-+-~_ +-H+-l-ti-+'+ i -1i+H+++'r r IT 111_·t ,,~ . __ + I I '! ,. : i i ; I '. I Ii it ! rT" ,.-,..!

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V)

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+- ",=2.-['1' " " i" '++'11++' ..l'J.j :t t· '" 'U..i " ,=.:-==~L:;;= ~=l=e-' : T ... £it; : ~hl= ER -:tHit±±t= f.j=:~jt, + ;- • + + - H..L : : : . j -~ Jt-h. ~ ± r---!-- " I I I j Ii- I I fl I , i-tTr-! I 'I , I tJ!

-1--'''1-+- "'--~ t-'.,-· .~ H-' d--W-. I!" ++ '~i:i i'+' ++l +1· - I,i-' ++H -:J ----i--".~.~±~:~: I : t-=t---=t:t±_~ i--01f l-y±·j I-il' .. t'.+t i~! .u-±t: .=j-tl- . .-j t - i --f-- --rt£f+ J±l± -r 'h.L:r- <r

'--... . , i , ..•. ,-1'" i'i. 'm " '+++ H-++ IHH~ t±i'" iI'l ++, ,.---.--,,--, ,'1"- ---'-.. -1- -. '---rr--+ -,-;-j" , "r - 'r - . - - --j-'''' . , ,J , II' ':1 " . i l~ ! I I ,

0.01 0.05 0.1 0.2 0.5 2 5 10 20 30 40 50 60 70 80 90 95 98 99 99.8 99.9 99.99

I"'U'>I'M 0/

1 c.n l\:)

1

-53-

to calculate the graphic mean and inclusive standard deviation of

Folk (1974) for each sample.

This technique is explained in Folk (1974). For the benefit of

the reader, however, the following summary is included. From the

cumulative frequency curves (Figs. 2-13), the grain-size values

(in p ) corresponding to the 5th, 16th, 50th, 84th and 95th percentiles

are ,determined. Using these values and the following formulae, the

mean (Mz) and inclusive standard deviation (~l) are computed.

Mz = ¢ 16 + 1> 50 or Sf! 84 3

r I = q)95 - ¢ 5 6.6

f;84 - ¢16 + 4

(1)

(2)

The results of these analyses are given in Tables I and II. Table

I lists means and inclusive standard deviations for all samples,

analyzed and classifies each sample according to the graphic mean

(Folk, 1974). Table II lists the relative amounts of mud, sand and

gravel in each sample. These data were plotted on triangular coor­

dinates (Fig. 14) to::determine the grain classification by an alter­

nate method.

-54-

APPENDIX II

TABLE I

Sample Mean (Mz)- ¢ Grain type* Standard Deviation (<f:d- ¢

0-1 0.47 (.72mm) Coarse sand 1.87 (Poor) 0-2a 0.97 (.51mm) Coarse sand 1.86 (Poor) 0-2b 2.28 (.21mm) Fine sand 1.23 (Poor) P-3a 3.23 (. 11 mm) V. fine sand 1.03 (Mod-Poor) P-4a 3.07 (. 1 2mm) V. fine sand 1.07 (Mod-Poor) B-5a 0.63 (.65mm) Coarse sand 2.09 (V. poor) 8-5b 0.40 (.76mm) Coarse sand 1.67 (Poor) B-5c -0.47(1.39mm) V. Coarse sand 1.37 (Poor) B-6a 2.57 (.17mm) Fine sand 1.31 (Poor) B-6b 2.27 (.21mm) Fine sand 1.53 (Poor) B-7a 1.75 (.30mm) Medium sand 2.09 (V. Poor) B-7b 2.04 (.24mm) Fine sand 2.00 (V. Poor)

* According to Folk (1974), p. 25.

-55-

A PPENDIX II.

TABLE II

Sample % gravel (>2mm)

msG 0-1 37.2 gmS 0-2a 26.7 S 0-2b 1.7

(g)mS P-3a 2.2 (g )mS P-4a 2.0 msG B-5a 38.0 msG B-5b 33.5 msG B-5c 46.5

(g)mS B-6a 1.6 (g )mS B-6b 1.8 gmS B-7a 15.9 gmS B-7b 13.2

Major Textural Class

G. GraveL .•.•....••..•............ C<mgiOmerate ..............•....

sG. Sandy gravel ......•.........••.. Sandy conglomerate ...•... " .. , ..

msG. Mu~sandy gravel .......•..... Mu~ ~ndy conglo~ ...... .

mG. Muddy graveL ........•......... Muddy con~~ate ............ .

gS. Gravelly sand ....•............•. Congl~atic sandstone ...•..•..

gmS. Gravelly muddy sand ............ . Conglomeratic muddy sandstone .. .

gM. Gravelly mud .....•..•...••...•. Conglomeratic mudstone ........ .

(g) S. Slightly gravelly sand ...... , .... . Slightly conglomeratic sandstone ..

(g)mS. Slightly gravelly muddz sand ..... . Slightly conglomeratic muddy

sandstone ..................... .

(g)sM. Sli~htly gravellz sandz mud ...... . Slightly conglomeratic sandy

mudstone ..•...•..•...........•

~g)~L Slightly gravelly ~ ............ . Slightly ~nglomeratic mudstone .. .

S. Sand (specify sorting) ........... . Sandstone (specify sorting) ........ .

mS. MuddZ Sand ..•...... " ......... . MuddZ ~~ndstone ................ .

sM. Sandy mud ..................... . Sandz ~stone (specify structure)

M. Mud ............•......•...•.... Mudstone (specify structure) .... '"

% sand (.0625-2mm)

59.7 68.6 91.1 73.1 78.8 54.2 59.5 50.3 86.5 87.9 69.2 69.9

% mud «.0625)

2.9 2.7 5 .1

24.7 16.9 6.6 6 .1 1.3

1 O. 7 8.8

11. 7 16.1

TRIANGULAR CO-ORDINATE

, \ _ ,e

~~~~.l

'-¥-' APPENDIX II, Figure 14. Triangular coordinate

li/~/;~i&">. graph showing the classification (after Folk, ~ / of the Gallows Bay samples. Note that most samples are classified as sands.

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-57-

RESULTS

All of the samples fell into the sand range according to mean

grain-size criteria (Table I). If considering the relative importance

of gravel, sand and mud, however, (Table II and Fig. 14) some of the

coarser samples (0-1, B-5a, b and c) are considered to be gravels.

It is felt that both these standard classifications are somewhat

confusing in this case, however. From these classifications, one

would envision a much coarser material than was observed in the field

(Table III).

Two points should be emphasized to clear up this problem. First,

the samples were in all cases, poorly sorted. For example, sample

B-5a contained 38% gravel (> -1 .O¢ ) and 16% material less than 3.0~

(very fine sand and mud). As a result, the mean grain-size of O.63¢

(coarse sand) ref,lects neither of the major constituents. The grain­

size curves (Figs. 2-13) should, therefore, be carefully examined

in each case, in conjunction with the sample descriptions (Table III).

Secondly, it should be noted that despite the fact that the amount

of material found in the sand range is consistently in excess of 50%,

much of this material occurs within the 3-4~ range (the border between

fine sand and mud - see Table IV). For example, although samples P-3a

and P-4a (in the proposed dredge site) contain over 70% sand, more than

half of this is within the 3-4¢ (very fine sand) range. If one takes

into account the fact that ~ome researchers contend that 3-4~ should

be considered as mud, then the whole picture changes and a better

appreciation of the nature of the sediment is attained.

-58-

APPENDIX II.

TABLE III

Sample Descriptions

0-1: Taken on the upper surface of the floodway delta; surface littered with pebbles and gravel. Sediment is similar through upper 30+ cm of core. Surface sample taken.

0-2: Taken in 20 cm of water on delta front; turns quickly to mixed mud and fine sand

a) upper 15 cm b) second 15 cm

pebbles on surface only; quickly.

P-3a: Taken along inner portion of small dock, in 210 cm of water; Core was generally mud with coarse sand pods and lenses (primarily occurring at a depth of 15 cm).

P-4a: Taken along outer portion of small dock, in 210 cm of water; sediment similar to that found in core P-3a; in addition, a rooted or organic lImat ll was often encountered when the bottom was probed.

B-5: Taken midway between the two docks in approximately 5 m of water; medium to fine sand formed a thin (1-3 mm) cover on the bottom; core was predominantly fine sand and mud to a depth of 15-20 cm; at this point a gravel layer was encountered.

a) upper 15 cm b) 15-25 cm (mud with pebbles) c) 25 cm (gravel)

B-6: Taken 35 m NW of delta front, in 50 cm of water; upper portion of the core consisted of mixed fine sand, mud and gravel; below 15-20 cm a gravel and cobble layer was encountered which could not be penetrated. Several cobbles up to 15 cm across were dug out by hand.

a) top 10 cm b) 10 - 20 cm (mud and fine sand were cored, larger clasts

could not be sampled)

B-7: Taken 1/4 of the way between the large dock and the opposite shore, in 5-6 m of water. Core was extrem.ely "stiffll and cohesive. It is estimated that 30% of the sample is smaller than 4.5 ¢ and beyond the range of seive analysis; therefore the Mz calculated for this sample will not completely reflect the nature of the bottom.

a) upper 10 cm - mud b) 10-30 cm - similar c) 30 cm - mud with strong blue color - probably from

Cretaceous volcanics; much of sample beyond the range of seive analysis.

-59-

APPENDIX II.

TABLE IV

Percent of sample in the 3-4 ¢ size range.

Sample Percent

0-1 10.S 0-2a 8.7 0-2b 20.8 P-3a 44.3 P-4a 40.6 B-Sa lS.7 B-Sb 7.9 B-Sc 2.4 B-6a 31.6 B-6b 29 .2 B-7a 26.0 B-7b 29.7

-60-

Based solely on the grain-size analyses conducted, two conclusions

are made with relative confidence. First the area is rather uniform in

its sediment distribution. Although most of the samples fall into the

fine sand range, sorting is poor in all cases, masking the true grain­

size distribution, as discussed above. The finest sediments were

found to be concentrated in the area of the proposed dredging. Exceptions

were samples 1, 2 and 5. 0-1, D-2a and D-2b were taken from the delta

fronting the flood spillway. The coarseness of the delta is a function

of proximity to the sediment source. During periods of high run-off, '

large quantities of material are deposited on the delta as the current

flow rapidly diminishes in the bay. Samples Sa, 5b and 5c were taken

from the turning basin between the two docks. The reason for the

consistent coarseness of these three samples is unclear, but may be

related to either the water depth,position of the basin with respect

to the main tidal flow, or the frequency of larger ship traffic in this

area.

The second conclusion is related to the source of sediments in

the bay. It seems obvious that the major source of sediments is run-off

during rain storms. Furthermore, the storm spillway is suspected e

as the main avenue for these sediments. The general trand seems to

be a concentration of coarser sediments in the delta area and a sea-

ward fining across the bay; sediments at B-7 were extremely fine.

Also, the concentrations of bluish material in the finer sediments

further suggests an origin in the Cretaceous volcanics occurring in

the Christiansted area (perhaps the mineral is clorite).

-61-

The gravel lenses found in the bay probably record major events,

such as the floods of last fall. During such extreme storms, sand

and gravel could easily be transported to the central portions of

the bay and remain untouched by subsequent tidal flow. Sediments

incorporated in the delta would be likewise redistributed by waves and

tidal currents. In addition, these shallower areas can be significantly

and adversely affected by boat wakes.

DISCUSSION

One of the primary considerations of the proposed project should

be transportability of the sedimentary fill in the area. For that

purpose, a number of relationships have been empirically derived to

predict the velocity needed to iniUate movement of a bed of given

grain size. Figure 15 is one such diagram used by the U. S. Army,

Corps of Engineers (U.S. Army, 1966), based on terrigenous data.

Because most of the material in the project area is either of terrigenous

origin, or else is quite fine-grained, it is felt that this diagram

applies. It can be seen from Figure 15 that most of the sediments could

be moved by currents on the order of 0.8 - 1.0 ft/sec (24-32 em/sec).

Similar current velocities would be required to move sediments in

+3.0'¢ to +4.0 ¢ range. Because much of the materi ali n the bay

falls within this range (see Table IV), this value becomes quite

important. It should be further noted that currents as small as 17 cm/

sec (.55 ft/sec) could maintain 3.0¢ to 4.0¢ material in sus.pension,

once it was initially disturbed. These factors should be integrated

with current data collected as another phase of this project to

determine the potential impact of the proposed work on the area.

-62-

APPENDIX II.

10

8

6

4 Upp~r Limit\ ~~

"0 ~ c 2

Eroding Velocities

0 u .,

V> ~ .,

CL

Q; 1.0 ., "- .8 ?: u .6 0

:> .4

f----+--'~"""<:~K)()<&E'x ~~. ~ to-. ...

, ,~~ ~>-D ~~ t,',' ,-..,,:: i j,"

Lower Limit

Figure 15: Graph of mean velocities required to erode sediment of various grain sizes. Note that all samples require but 0.8-1.0 ft/sec of current to move them. Threshold velocities in the 3.0~to 4.0¢ range (shaded zone) are of similar magnitude.

-63-

APPENDIX II.

REFERENCES CITED

Folk, R. L., 1974, Petrology of sedimentary rocks, Hemphill Publishing Co., Austin, Texas, 182 p.

U. S. Army, 1966, Shore protection, planning and design, Tech. Rpt. No.4, 3rd ed., U. S. Army Coastal Engineering Research Center, Washington, D.C., 401 p.

-64-

APPENDIX III.

HISTORY AND ARCHAEOLOGY OF GALLOWS BAY

by

George F. Tyson. Jr. Director of History and Culture

Island Resources Foundation St. Thomas. U. S. Virgin Islands

-65-

Gallows Bay is a bowl shaped cove, one-third mile wide, located east of Christiansted and west of Mount Welcome. It is so named because under the Danes the place of public execution and correction was loc­ated in its vicinity, at one point just behind the western shore near Fort Christianvaern (see Appendix III, Maps 3,4), and later behind the south­ern shore, near the intersection of East End Road and Public Road (see Appendix III, Maps 5,6).

While its association with the gallows certainly constitutes a dramatic cultural feature, the bay area historically has been the scene of a variety of human use patterns, including maritime commerce, agriculture, fish-, ing and recreation. Through old maps, charts and paintings, it is pos­sible to reconstruct a skeletal framework of its historical development.

No evidence survives that Gallows Bay was inhabited by pre-Columbian peoples. Though the ecology of the south shore makes it a likely Amer­indian settlement site, periodic flooding and beach erosion, as well as dredging, fill, construction and other human impacts along the shoreline, have effectively obliterated any surface remains of pre-Columbian habit­ation.

The earliest documentation of human settlement around Gallows Bay dates from the mid-seventeenth century. A crude Spanish map of 1649 depicts one small habitation south of the southern shore line, and a larger structure near the southeast corner, just below Mount Welcome. A 1671 map by the Frenchman Lapointe identifies a French estate as being sit­uated near the southwest corner.

Another French map of 1682 (see Appendix III, Map 1) shows a few build­ings in the vicinity of the northwest point of the bay (near the site of pre­senf day Fort Christianvaern), where a small earthenwork fort is known to have been constructed by the French. Two other buildings, one pos­sibly a church, are located at the northeast point of the bay. A road, running just behind the shore line, connects the buildings at the northwest and northeast points. Otherwise, the bay appears in its natural state with no evidence of buildings or agriculture in the plain behind it.

No new developments seem to have taken place in the bay area between 1696, when the French evacuated St. Croix, and 1734, when the Danes began to settle the island. A rough sketch of Christiansted harbor. drawn by Lt. Peter L. Stibolt in 1735 (see Appendix III, Map 2), shows no struc­tures along the bay, except at the northwest point, where the Danes had

-66-

built an earthenwork fort which would, in a few years, be reconstructed at Fort Christianvaern. A Spanish map drawn about the same time by F. de Valdelomar confirms Stibolt's characterization.

For many years Fort Christianvaern remained the only significant struc­ture along the bay. Beck's town plan of Christiansted (1752) and a 1756 Danish chart of the harbor (see Appendix III, Map 3) both show that the town of Christiansted had not expanded to the western shore by mid-century.

Commercial development, however, wouLd soon engulf the western portion of Gallows Bay. Christiansted was becoming a trading community of re­gional importance, and between 1758 am 1786 its population more than doubled (from 2, 175 inhabitants to 4, 78,7). By 1760, as shown by Hans ZolLner'S town plan (see Appendix III, Map 4), and a drawing of the harbor by J. von Rohr, commercial development had started along the western shoreline, first next to the Fort and then moving southward. Two decades later, as shown by Peter Oxholm's 1777 map of St. Croix (see Appendix III, Map 5) and a 1779 town plan of Christiansted (see Appendix III, Map 6), the street network of the city extended behind the southern shore line, along Garden and Green Streets. It is evident from the 1779 plan that several wharfs and docks had been erected along the western shore, as well as a few warehouses. One major building had also been built near the south shore, at the eastern end of Garden Street.

The last half of the eighteenth century witnessed the peak of commercial activity along the western shore of the bay. Little had changed when Oxholm made a new map in 1794. And a series of painting:;of the harbor area, drawn in the first half of the nineteenth century, depict only a few commercial buildings, fenced by wooden stockades along the shoreline, and interspersed by clusters of trees, along the western shoreline. It is not until the 1960's, when the Virgin Islands government constructed port and dock facilities along the eastern shore, that the bay regained its importance as a commercial and maritime center.

In addition to its commercial history, Gallows Bay has traditionally served as an important fisheries center, serving the Christiansted pop­ulation. The existence of a major thoroughfare named Lobster Street, connecting Christiansted proper with the bay at its southwest corner, indicates that by the 1770's, if not earlier, a respectable fishing industry, and perhaps community, had sprung up in that corner of the bay. A painting by W. Melbye (c. 1850), showing Afro-westindians fishing by boat and by net along the eastern shore, demonstrates that fishing con­tinued to playa notable role during the nineteenth century. Today,

-67-

Gallows Bay serves as an anchorage and staging ground for the fishing activities of approximately 30 boats. The Port Authority cargo dock is a focus of considerable recreational fishing activity.

Agricultural usage of Gallows Bay area dates from the second half of the seventeenth century, when, according to Spanish and French maps of the period, a few small estates were situated behind the southern shore. Under the Danes, however, agricultural deve lopment was s low in coming, due, in part, to the expansion of Christiansted along the western shore, the close proximity of Mount We lcome behind the eastern shore, and the pre­sence of a small lagoon and salt pond just beyond the southeast corner.

The existence of the small lagoon and salt pond, both of which have since disappeared, is most apparent from the Oxholm map and plan of 1777 and 1779 (see Appendix III, Maps 5,6). The kidney shaped lagoon, called "Little Lagoon" by Oxholm, was located just behind the southeast corner of the bay, to which it was connected by a narrow channeL. Just to the west of the lagoon was the small salt pond. The lagoon and salt pond are not shown in most earlier maps. However, the Lapointe map of 1671 clearly designates it, and its channe I is depicted on the Zollner plan of 1760. The Little Lagoon was a distinguishing natural feature of the bay area in the eighteenth century. Its channel served as the dividing line between human settlement on the west and the surviving natural landscape to the east. The gallows was situated near it, and it inhibited agricultural deve lopment.

Sometime between 1794 and 1856 the Little Lagoon ceased to exist. The Oxholm map of 1794 shows it clearly (although the small salt pond had disappeared), while it is not depicted on the Rohr map of 1856 (see Appen­dix III, Map 7). Just why and when the disappearance took place is uncer­tain. However, a few pairiings of the period suggest an answer.

A view of Christiansted from Peter's Farm, painted by Otte around 1830, shows the land behind the southern shore line and the southeast corner of the bay as being cleared and under cultivation, the first evidence of agri­cultural usage under the Danes. A lagoon-like body of water appears to be situated between the cultivated land and the beach, but the representa­tion is too indistinct to be certain that it is the lagoon. More definite is a painting of Christiansted from the BUlowsminde estate done in 1834, which shows aU land behind the southeastern shore to be under cultivation. The Rohr map of 1856 does not depict the lagoon at all, and identifies all land along the southeast corner as be longing to Mount Welcome. On the

-68-

basis of this information, it can be conjectured that the Little Lagoon and the surrounding area were brought under sugar cane cultivation by the owners of Mount Welcome eeate in the 1820's, who also appear to have constructed a windmill just below Mount Welcome at the southeast corner.

How long commercial agriculture persisted around the southeastern sec­tion of the bay is not known. In all probability it lasted until the early twentieth century, when sugar cultivation was reduced throughout the is­land.

In an associated development, an abattoir was built on the eastern shore­line around the turn of the twentieth century (indiCating that the surround­ing countryside may have been used for stock farming). It remained in existence until 1961, when it was demolished to make way for the present dock facilities.

While agriculture is no longer practiced around the bay today, at least some historical continuities are evident. Fort Christianvaern at the northwest corner, one of the earliest buildings constructed along the bay, still stands. Maintained by the U. S. National Park Service as part of the Christiansted National Historic Site, it is recognized as a classic example of seventeenth and eignteenth century Danish colonial architecture. The bay continues to support a small local fishing industry. And, currently, most of the maritime commerce for St. Croix is handled by the port fac­ilities along the eastern shore.

Except for the spectacular Fort Christianvaern, the bay displays little visible evidence of its history before the mid-twentieth century. The abattoir and the Mount Welcome windmill were demolished to make way for the east shore dock and marina facilities. The concrete and steel dock faciJitiesbear no resemblance to the wooden stockaded wharfs and brick warehouses of the eighteenth century. The old residential habit­ations along Garden and Green Streets have been replaced by concrete houses of recent vintage. The impression is that around the bay history has not stood still, but is in the making.

APPENDIX III. -69-

MAP #1. French map, 1682

APPENDIX III. -70-

MAP # 2. Lt. Stibo1t'map, c. 1735

•

-71-APPENDIX III.

MAP # 3. Danish town plan, 1756

Arrow denotes the gallows.

. .

.' ~

APPENDIX III. , . ': (

',t. 4, ~ ... ' It;. "l-..I

";~ ~".. . . . . .

." ,.

. -;.

.' -. •

, -- -- - --- - ----._-- --

-72-

, •• II l ' I ::,..,' :t .. f,~:'" ~.' , - _J. _____ -4 ,,:"~~/

-f· . __ J ---t

.' ,,,' \', '\ :.

" 0"'

• , , r i;. i., ,~ It . . ~, :' '.:; ,

• . ~l" •

:. ..: ... :. • ~.',ol !

: . ~ ~. 1,~ , . ' ...... 1

. t '.

, ,.," .1 •

MAP #4. H. Zo~lner town plan, 1760

Arrow denotes the gallows.

-73-APPENDIX III.

L , .. .x-, If

/9. II

bi.~ X· I/~ ,1

i)' ~I.\ a.'. /1. ' to.' : ,<II

MAP #5. Oxholm map, 1777

Arrow denotes the gallows.

-74-APPENDIX III.

MAP #6. Oxholm town plan, 1779

Arrow denotes the gallows.

~

I,

,i ~

"

.APPENDIX III.

'. -. /' " . ,

' .. ' .. ! .. , ~ ,

". . .' ,. :,' . , ;, 1''''' ••

• • I. ~ "'~.' ..

-.

~ ,..

"'" flo

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••

...

.. ..... " .

. ' ..

. .... > •

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MAp # 7. Rohr town plan, 1856

-75-

. r. ~' "

. . ~. ~ '.',

, , . ~ , \ .......

-76-

APPENDIX III. SOURCES

Printed Danish R.oyal Academy of Fine Arts, Three Towns (1964). Johnson, Clarence L. and David J. Jones, Historic Sites of St. Croix,

Virgin Islands of the United States, Part I, Wharf Area of Christiansted, (Department of the Interior, 1951).

Olsen, Herbert, Fort Christiansvaern, Christiansted, St. Croix, (Historic Structures Report, Part I, Dept. of Interior, 1960).

Vesce lius, Gary, et. al., The St. Croix Archaeological Project, General Report. MaY1951 - September 1952.

Maps 1649 Spanish map of St. Croix from Archives of Seville 1671 French map of St. Croix by Lapointe from Royal Library, Copenhagen 1682 French plan of Christiansted harbor, from Bibliotheque Nationale, Paris

c. 1735 Danish map of Christiansted harbor by Lt. Peter von Stibolt c. 1735-6 Spanish map of Christiansted harbor by Fernandez de Valdelomar

1752-54 Danish map of St. Croix, with inset of Christiansted harbor by Jens M. Beck

1756 c. 1760

1777 1779 1794 1856 1856 1876 1906 1924

Danish map of Christiansted harbor from Royal Library. Copenhagen Danish plan of Christiansted harbor by Hans ZoUner Danish map of St. Croix by Peter Oxholm Danish plan of Christiansted by Peter Oxholm Danish map of St. Croix by Peter Oxholm Danish plan of Christiansted, by Rohr British map of St. Croix by John Parsons American map of Christiansted harbor by Capt. Washington. U. S. N. Danish chart of Christiansted harbor U. S. Coast and Geodetic Survey. Christiansted harbor, Chart #1058

Drawings and Paintings c. 1760 Fort Christianvaern and Christiansted harbor by von Rohr

1815 Prospect of Christiansted by H. G. Beenfe ldt c. 1830-31 View of Christiansted from Peter's Rest by Otte c. 1834 View of Christiansted from Bulowsminde c. 1845-51 Fort Christian by W. Melbye c. 1856-57 Christiansted and Fort Christianvaern. Lithography from drawing

by P. Seide lin c. 1865-6 Fort Christianvaern by Fr. Visby

-77-

LITERATURE CITED

1. Bowden, M. J., 1968. Water Balance of a Dry Island, Dartmouth College, 89 pp.

2. Bowden, M. J. 1974. Hurricanes in Paradise. Island Resources Founda­tion publication. 115 pp.

3. Corps of Engineers, U. S. Army, 1975. Flood Plain Information Tidal Areas. St. Thomas, St. Croix, and St. John, U. S. Virgin Is­lands. 43 pp., 24 plates.

4. Dong, M. eta al. 1973. The role of man-induced stresses in the natural eVOLUtion of Long Reef and Christiansted Harbor, St. Croix, U. S. Virgin Islands. West Indies Laboratory Report. 4 pp. 1 plate.

5. Francois, P. and Brown, V. 1975. Report on Water Quality, Virgin Islands, U. S.A., 1970 - 1975. 25 pp. plus appendices.

6. Jacobsen, A. R. 1951. A study of the pollution of the harbor waters of the Virgin Islands. Files, Virgin Islands Dept. of Health.

7. Madigan-Praeger, Inc. 1974. Report on Plans for Seaport Development and Relocation for the V. r. Port Authority. 150 PI'. with maps and exhibits.

8. Nichols, M. eta al. 1972. Environment, Water and Sediments of Christian­stedHarbor, St. Croix. Caribbean Research Institute Rpt. 16. 141 pp,

9. Rainey, W. E. 1976. Preliminary Report on Sea Turtle'S in the United States Virgin Islands. Island Resources Foundation Pub. 23 pp.

10.Rebel, T. P. 1974. Sea Turtles. University of Miami Press. 250 pp.

11. Rivera, eta al. 1970. Soil Survey. Virgin Is lands of the United States. U.S. Dept. of Agriculture, Soil Conservation Service Publ. 80 pp.

32 plates.

12. Robison, T. M. 1972. Ground Water in Central St. Croix, U. S. Virgin Islands. U. S. Dept. of Interior, Geol. Survey. Rpt. 18 pp.

-78-

Literature cited - (cont. )

13. Stone, H. G. 1942. Meteorology of the Virgin Islands, Scientific Survey of Porto Hico and the Virgin Islands. N. Y. Academy of Science. Vol. XIX. 138 pp.

14. Whetton, J. T. 1972. Field Guide to the Geology of St. Croix (in) Geology-Ecology St. CroLX:. U. S~ V. 1. Multer and Gerar~ ed. West Indies Laboratory pub. 303 pp.

15. Zube, E. H., 1968. The Islands: Selected Hesources of the U. S. Virgin Islam s. University of Massachusetts, 71 pp.