Ecosystem Change and Management Response on Tropical Island Ecosystems to Link Land-use Change,

Coastal Wetlands and Marine Fisheries: Case Study of Victoria Pond, The Bahamas

KATHLEEN SULLIVAN SEALEY

Department of Biology, Coastal Ecology Lab, University of Miami, Coral Gables, Florida 33124 USA,

(Corresponding author ksealey@miami.edu) and

JOHN A BOWLEG

Water and Sewage Corporation; Chartered Water & Environmental Manager, P.O. Box N-3905 Nassau, N.P.,

Bahamas

ABSTRACT (200 words)

The scale of watersheds makes interrelationships between the hydrological cycle, livelihoods and ecosystems

easily perturbed by land-use changes on small islands. The Bahamas are challenged to develop management

practices to protect wetlands as part of the ecological connection between land and adjacent valuable marine

resources. Victoria Pond, a large mangrove lake in the center of George Town, Great Exuma, is the terminus of

a wetland complex draining into Elizabeth Harbour, a shallow marine lagoon. Land-use changes, including

eco-hydrological alterations (e.g. dredging marinas, filling wetlands, clearing forests) have led to coastal

hypoxic (low oxygen) events. Hypoxic events are characteristics of coastal eutrophication and the chronic

degradation of reefs and seagrass meadows. Assessment of eco-hydrological changes requires methods to: 1)

map wetland systems; 2) monitor water quality and ecological parameters, and 3) implement wetland

restoration techniques that are cost-effective. From 1996 to 2009, Victoria Pond and associated wetlands were

studied to document ecological degradation, especially decreased fish abundance. The Pond wetland restoration

project in the centre of George Town was initiated in 2009 to clean up a conspicuous eye-sore, and demonstrate

best practices for restoring wetlands adjacent to human settlements. Restoration methods included construction

of coastal buffer zones or easements, and widening canals to increase connectivity for water flow over tidal

cycles and storm events.

Key words

Coastal wetlands; mangroves; water quality; coastal hypoxia; coastal restoration; The Bahamas; Great Exuma;

fish habitat, land-use change, water quality

INTRODUCTION

Victoria Pond is a mangrove lake that is part of large coastal wetland complex, and is at the centre of

George Town, Exuma, The Bahamas. The settlement is built around the Pond which provides natural beauty,

fish habitat and waterfront access. The Pond has suffered from the lack of coordinated management and poor

coastal development practices, and is now polluted and overgrown with invasive plants. The Pond’s drainage

canals are clogged with trash and presents a real public health threat with rats, mosquitoes, and leaching of raw

sewage. The Pond and its associated wetland components have lost ecological function and beauty on an island

with a tourism-based economy. The Victoria Pond Restoration Project looks at how to reverse years of poor

management; the goal is to rehabilitate a human community to stop dumping trash, sewage and effluent into

Victoria Pond, and build better wetland stewardship with measurable benefits to fish production and ecology-

based tourism.

The Victoria Pond project has brought together a team of scientists, local businesses and the Exuma

local government council to make the public connection between coastal zone management and health of the

tourism economy on Great Exuma. This case study outlines the ecological degradation that has occurred, the

cost of ecological damage to the community, and the restoration project action plan. The wetland restoration is

on-going, and presents a learning experience on the cost of environmental damage to entire community, as well

as the economy of prevention over restoration. The critical component for success is community involvement

in the coastal management practices beyond the physical restoration of mangrove wetlands.

Overview of Victoria Pond Restoration Project

Public-private partnerships have started to restore the wetland landscape to enhance tourism, fish habitats, and

quality of life around George Town. The goals of the Victoria Pond Restoration Project are: 1.) To establish a

local mangrove preserve as per The Bahamas National Wetlands Protection Policy (BEST, 2007) 2.) To

complete the necessary clean-up, excavation and restoration needed to re-establish connectivity and natural

drainage between wetlands and adjacent marine environments ; 3.) To develop long-term community outreach

and coastal stewardship programmes to finance the preserve; and 4.) To document measurable improvements in

coastal water quality and near shore fish assemblages from restoration actions.

Assessment of eco-hydrological changes required methods to: 1) map a reconstruction of the original

wetland system, 2) monitor water quality and ecological parameters linked to coastal hypoxic events, and 3) test

wetland restoration techniques that are cost-effective. The restoration of wetlands in the middle of a human

settlement require measures of success based on public participation in environmental stewardship activities as

well as compliance with wetland protection laws and policies. The restoration project has brought attention to

the value of the ecosystems services; humans benefit from the ecological health of coastal systems, especially

on islands with tourism-based economies. The restoration project itself focused on key components:

(a) The engineering/ construction component to “fix” the restricted flow and impoundment issues; heavy

equipment is required to remove trash and fill illegally dumped in wetlands, add culverts to causeways built

across wetlands, and clear or expand canals connecting various ponds and wetlands in linked drainage system.

(b) The ecological component to “repair” the damage from cutting and removing mangroves. Rock revetments

are constructed, and mangrove seedlings are replanted along the newly stabilized canals, culvert systems and

wetland area. In addition a 4-meter coastal buffer zone is established and vegetated to protect mangroves with a

zone of associated native coastal plants, and

(c) The outreach component to engage the community in the restoration efforts, and link environmental

stewardship to livelihoods on the island. Maintaining a clean and functional ecosystem can stimulate economic

activities such as recycling projects with businesses associated with recycled material .

The outreach component remains the most challenging. All stakeholders around Victoria Pond and George

Town area need to be engaged at some level of participation, and support the overall goals and costs of wetland

restoration with on-going maintenance.

Historical and Ecological Setting

Great Exuma is the largest island in the Exuma island chain, with nearly 8,000 residents living on the

island in six major settlements (Department of Statistics, 2011). George Town is situated in the centre of the

Bahamian archipelago, exactly on the line of the Tropic of Cancer and fronting one of Elizabeth Harbour, an

important natural harbor and marine lagoon (Figure 1). George Town, Exuma has less than 1,000 permanent

inhabitants, it is often claimed that it might have equaled Nassau in importance had history not passed it by.

Loyally named after an English monarch (George III) like many other notable colonial townships, George Town

was specially laid out by a parliamentary act of 1792 to be the administrative centre for the Loyalists who first

settled Exuma with their slaves after the American War of Independence. The era of international peace

following 1815, along with the complete failure of Bahamian cotton plantations along with the abolition of

slavery drastically punctured these plans in Nassau’s favor, and George Town grew only at a snail’s pace .

George Town is now a tourism destination for boating, diving and fishing. The ecology and environmental

quality of the island attracts visits (Lowe and Sullivan Sealey 2001). The clear water, coral reefs, and abundance

of marine fish are critical to the Exuma culture and tourism economy.

During the Plantation Era (1760-1810) a handful of structures were built, including a church and

parsonage, a courthouse with a jail, government dock and market square, warehouses, a slave house (much later

converted the hotel Peace and Plenty) and a few town houses for the local gentry. These buildings were all

located on the small ridge and peninsula between Elizabeth Harbour and a circular lake later named Victoria

Pond. After slavery ended, George Town became the population center; residents settled mainly around the

Baptist church on the opposite side of this tidal lake. Victoria Pond was the largest and deepest of a series of

connected mangrove lakes and wetlands that provided critical wildlife habitat as well as controlled flooding

along the eastern ridges of Great Exuma. The Pond supported schools of tarpon, and nursery habitats for fishes

such as grunt and snapper. Fish was and is the mainstay of the local diet.

George Town’s Victoria Pond was a centre for ship careening and repair. Originally, Victoria Pond, and

many inland saline lakes did not have surface connections to Elizabeth Harbour, but rather subterranean

connections through the cavernous limestone. The extreme oligotrophic (low nutrient) conditions of the marine

near shore systems were maintained by a complex filtering of freshwater run-off through these wetlands and

ponds. A narrow cut was made through the limestone ridge to pull boats into the protection of Victoria Pond in

the early 1800’s (appearing on the 1890 land map, Figure 2). This cut established a surface connection and tidal

exchange from Victoria Pond and the adjacent Elizabeth Harbour (Figure 3). The Pond is used for small

outboard boats, and even some shipbuilding occurred in the early 20 th century. The township had minor surges

of activity when small United States of America (USA) bases were established during World War II, and again

for anti-drug surveillance in the 1980s. The USA Navy bases were notable for the amount of dredging and

removal of seagrass that occurred in Elizabeth Harbour to accommodate amphibious plane operations. This

dredging became significant historically with the subsequent loss of seagrass meadows and increasing turbidity

and water quality issues occurring around George Town and Elizabeth Harbour (see Sullivan Sealey 2000).

Despite the six-fold increase in the Bahamian population and the 20-fold increase in the size of Nassau, George

Town’s population has not doubled since 1906. While George Town remains the administrative and modest

commercial centre of Great Exuma, it is fairly quiet throughout most of the year. For a week in April, however,

George Town becomes the focus of nearly all activity in the Family Islands, serving as the host location (since

1953) of the Family Island Regatta. The Regatta can bring hundreds of sailboats and over 10,000 visitors .

Great Exuma has historically gone through boom and bust cycles of tourism; most recently dropping

from a peak of 44,131 stopover visitors in 2005 to only 20,594 stopover visitors in 2009. The Bahamian

resident population fluctuates accordingly. Sailboats and yachts visit George Town in the winter (dry season)

months; boating tourists generally move north during hurricane season (June through November). The challenge

for George Town is to provide adequate infrastructure for businesses and special events while maintaining the

beautiful and historic coastal environment that attracts tourists and residents alike.

Wetland, Coastal Hypoxia and Loss of Ecosystem Function

Ecological studies of the Exuma Cays were initiated in 1988 to document the unique habitats within the

Exuma Cays Land and Sea Park (Sluka et al 1996, Chiappone and Sullivan Sealey 2000). Bahamian national

parks provide “control areas” for ecologists to understand wetland loss with coastal development impacts on

coral reefs and fish assemblages, and thus, the work in Exuma Cays Land and Sea Park became the basis for

planning ecological restoration to impacted areas such as Victoria Pond. Islands with their associated coral reef

resources are threatened by coastal hypoxia, a threat that can only partially be addressed by the creation of more

protected areas. The changes in coastal land use along with coastal alterations (e.g. dredging marinas, filling

wetlands, clearing forests) have created many small “hypoxia hot spots”; a major source of the hypoxia events

is the loss of natural wetland systems with the disruption in water flow, particularly after floods and rainfall

events (Figure 4). The filling-in and channelization of wetlands brings high nutrient- high sediment load run-

off directly into coastal wetlands and lagoons. Victoria Pond is the ideal case in point to investigate restoration

as a means to reverse coastal eutrophication and hypoxia.

Wetlands are wide-spread on Great Exuma, and include ephemeral freshwater wetlands (filled only with

seasonal heavy rains), hyper-saline ponds and mangrove embayment, blue holes and more extensive coastal

mangrove ponds and creeks. It is the wetland complexes along the island that filter and process storm water

run-off to maintain the oligotrophic conditions in the marine environment (Figure 5). Victoria Pond is part of a

larger wetland complex that is connected through surface water and subterranean flow to the adjacent Elizabeth

Harbour (Figure 6).

Victoria Pond today is a 6.8 hectare lake with fringing mangroves covering about 425 metres of the

1,010 metre perimeter. Less than 42% of the 1100 metre perimeter remains fringing mangroves, and over a

hectare of the Pond has been lost to fill for parking lots, boat ramps, and marinas. Victoria Pond historically

was connected to Eastern Pond, a shallower embayment to the southeast. The main road (Queen’s Highway)

heading south of George Town bisected the two ponds, and over time, the mangrove margins were filled to

create house lots, and the original connection was reduced to a narrow channel with a 4-foot box culvert under

the road. The roads around the Pond also blocked the flow from ephemeral wetlands to the west, trapping water

in impoundments. Ditching has been used to try to drain these ponds rather than restoring the original wetland

flow. The dismantling of the hydrological connections around Victoria Pond has been facilitated by the

subdivision of land into small family plots around the original George Town settlement (Figure 2); the small

land plots motivated individual land owners to fill in their property, often shifting water flow to other areas.

The most dramatic ecological changes have occurred in water quality and loss of seagrass meadows

with decrease in diversity of marine fauna within Victoria Pond itself. Additionally, there are wider impacts on

coral reefs just outside the Pond in the adjacent Elizabeth Harbour, linking human alterations and land-use to

marine resource degradation. The shallow bottom sediment of the Pond was sand-mud, primarily seagrass

meadows and sparsely-vegetated sand communities, with some scattered coral heads. As sections of the

mangroves were removed, storm run-off deposited finer sediments with high organic content into the Pond.

The flocculent material was re-suspended during storms or high wind. The re-suspended organic material

triggered algal blooms which increased turbidity and Biological Oxygen Demand (BOD) in the Pond with

limited circulation. The consequences of this cycle of increased organic loading of sediments, and less light

reaching the bottom for seagrass growth (Bell and Elmetri, 1995; Bell et al, 1989; Paul et al 1995) (Figure 7).

Water quality is especially impacted by storm events; rain run-off from the paved and cleared surfaces in

George Town allow, sediments, nutrients and other pollutants to directly enter the Pond system. Unequal semi-

diurnal tides carry these contaminants into adjacent marine environments such as Elizabeth Harbour. Elizabeth

Harbour is a true marine lagoon, not an estuary, with relatively high salinities ranging from 37 to 40 ppt, and

tropical oligotrophic conditions.

The ecological assessment of Victoria Pond environs began with the assumption that there were likely

three factors contributing to the decline in water quality and loss of ecological service: 1) physical damage and

removal of mangroves and other associated wetlands, 2) the seepage of sewage adding excess nutrients, and 3)

resulting loss of ecosystem diversity over time. Healthy mangroves and reef systems need spiny lobsters,

snappers, grunts and groupers; in other words, the full complement of species in the natural community help

protect the natural community from change (e.g. ecological stability and resilience) (Buchan 2000). For

whatever the reason, populations of essential marine species like reef fishes, lobster, and queen conch are

reported to have declined in the George Town environs, especially adjacent to heavily used areas such as

Victoria Pond.

Residents of George Town expect the ecosystems around them to function to process pollutants, to

recycle nutrients and to support trophic relations that eventually produce fish, lobster and conch for local

consumption. Ecosystem services include stabilizing shorelines, protection of upland areas from flooding, and

maintaining biological diversity which in turn reduces pathogens and pest species such as flies, mosquitos and

rats (see Dailey 1997). Globally, the greatest threat to coastal ecosystems is hydrological alterations resulting in

excess nutrients and pollutants entering water resources. Eutrophication and hypoxia events are now

documented in all major coastal ecosystems worldwide (Diaz and Rosenberg, 2008; Burke and Maidens 2004).

The causes of hypoxia in large rivers and estuaries are complex, and related to large-scale changes in

land use that alter patterns of nutrients and sediment transported into the coastal waters. The scale and

persistence of hypoxia events can profoundly change the ecology and energy flow of marine ecosystems

globally (Diaz and Rosenberg 2008). However, on the islands of The Bahamas, nutrients and sediment also

enter near shore waters through ground water seepage and surface storm run-off, and this nearly-ubiquitous

exchange of freshwater and nutrients off small carbonate islands makes the coastal zone especially sensitive to

eutrophication with human disturbances (Cant, 1977)

Coastal restoration efforts within The Bahamas have focused on reversing beach erosion or protecting

coastal property. Few projects have been undertaken to restore coastal mangrove wetlands, and incorporate a

wetland preserve into a local community. The Victoria Pond Restoration Project includes the reconstruction of

coastal wetlands, coastal buffer zones as well as local governance commitments to manage land-use planning to

incorporate local wetland preserves. Much of the restoration is focused on physical alterations to restore flow

and create a vegetated buffer between homes and wetlands. However, the larger challenge is creating a

“stewardship” ethic where each resident takes a personal responsibility for wetland protection. It is likely that

micro-scale alterations and the action of individual residents will “make or break” the restoration project. The

goal is to reduce “hypoxia hotspots” that have greater ecological implications and measurably improve the

abundance and diversity of fish in the Pond system.

ASSESSMENT METHODS

The assessment of the eco-hydrological changes around George Town required the development of new

research methods for small islands to: 1) assessment of ecosystem function through characterization of the

original hydrological system, then 2) detect change in specific abiotic and biotic parameters linked to coastal

hypoxic (low oxygen) events, and 3) test restoration methods that are cost-effective. The methods can be

discussed in three sections, focusing first on the assessment of ecosystem function based on ranking the

“intactness” of the coastal environment, second on the water quality assessment, and third on the assessment of

near shore marine resources.

Assessment of Ecosystem Function

The selection of restoration sites was based on a systematic ranking of the coastal zone throughout

Exuma, and selection of areas with the greatest degradation of coastal hydrological processes as well as viable

restoration options. The assessment included both a characterization of the coastal environment and an

assessment of threats to evaluate how humans may have altered the nutrient cycles within the coastal

ecosystem. In 2002, a map of the land cover and near shore marine habitats was completed (Sealey et al. 2002).

The coastal zone was characterized in terms of coastal vegetation structure and coastal geomorphology (Table

2). The coastline of the entire Harbour was examined by ecologists to map altered coastal environments. A

recently completed vegetation classification scheme for the Bahamas provided five coastal vegetation profiles

around George Town, including human altered shorelines (e.g. bulkheads, fill and rip-rap). Coastal vegetation

communities play a role in stabilizing coastlines and controlling nutrient inputs from land to sea; in Exuma,

there are some 178 species of coastal plants on the checklist used in the coastal assessment (including

mangroves, saltwort, bromeliads, orchids and vines associated with mangrove wetlands). Restoration ecology

begins with understanding the full component plant species that occur along the coastal zone in unaltered areas.

A wetland community classification scheme (Cowardin et al. 1979, updated by Madden et al. 2009) was used to

apply a uniform nomenclature in naming coastal zones that have unique hydrological processes and

vulnerability to human impacts. Coastal impacts were ranked to compare between sites, and determine the

viability for restoration

Human impacts can alter the coastal environment in four basic ways:

(a) Physical restructuring (i.e. cutting through, causeways) of the shoreline by dredging canals and marinas, or

reclaiming seabed and filling areas;

(b) Destructive use of the coastal zone with vegetation loss from sand mining;

(c) Development including buildings, homes or other structures, with on-site waste water disposal and

vegetation replacement (e.g. lawns or gardens of non-native plants); and

(d) Volunteer invasion of alien plants from seed dispersal mechanisms.

The nature of the human alteration of the coastal zone determines the cost and practicality of restoration.

Physical restructuring requires the most time and resources; however, restructuring and replanting a coastal

wetland would have the best-long term success in reducing eutrophication.

The overall score of human impacts to the coastal zone is a compilation of the four separate parameters.

The most destructive impact to coastal areas involved physical restructuring of the shoreline by dredge and fill,

including road construction. For all of the impact criteria, the following guidelines are used in ranking: over

70% of the linear extent of the shoreline altered is considered a “severe” impact; over 50% is “high”, over 10%

is “medium”, and less than 10% of the coast physically altered would be a “low” impact area.

Two species of introduced invasive plants are able to propagate by sea-borne seeds. The Australian pine

(Casuarina equestifolia) and the beach naupaka (Scaevola sericea) are considered a threat to the stability of the

coastal zone and to native plant diversity by the Government of The Bahamas (BEST 2003). The sea borne

seeds of these two species can invade even intact and otherwise unaltered coastal segments. The combined

impact assessment produces a final overall coastal ranking score. This score indicates the ease of remediation.

The score also indicates a level of risk for coastal erosion, loss of wildlife habitat or loss of fish habitats. “Low”

or “Medium” impact ranks represent areas that can be improved by local stewardship actions, such as invasive

plant removal and some modest coastal restoration measures. “High” and “Severe” impact scores call for

larger-scale and higher-cost measures, such as backfilling dredged canals, physical re-structuring of the

shoreline environment, wetland restoration and removing causeways. The Victoria Pond Project area was

ranked as “high to severe” but with highly localized damage that was reparable (Figure 8).

Assessment of Water Quality and Coastal Hypoxic Events

The water sampling procedures followed standard water sampling practices; these methods are outlined

in Chiappone et al (1998). Water Chemistry stations were approximately 100 meters apart. Sampling occurred

over two-week intervals for 12 years, with at least one dry season (December through April) and one wet season

(May through November) sampling event each year. Samples were all taken within an hour of sunrise or

sunset, over a two-week period to cover the semi-diurnal tidal range. Water quality sampling was carried out at

sunrise when temperatures and dissolved oxygen should be at minimum values, and at sunset to detect

maximum temperatures. Dissolved oxygen at dawn will indicate the maximum biological oxygen demand

(BOD) in the water column. Samples were taken with a standard water-sampling bottle at the surface and near

the bottom of the water column in Victoria Pond.

At each sampling point, the following parameters were measured (for both surface and bottom water

samples): Temperature in degrees Celsius, salinity in parts per thousand (ppt), turbidity in Nephloid Turbidity

Units (NTUs), dissolved oxygen in milligrams per liter (mg/l), and total inorganic nutrients (nitrogen and

phosphorous) were recorded during the initial 2-year assessment in 1996-1997. Depth and benthic community

type were recorded to create a map of marine benthic communities. Results were reported in micromoles for

Total Nitrogen and Total Phosphorus. In tropical oligotrophic wetland and marine ecosystems such as Exuma,

the threshold for eutrophication is lower than the threshold of detection of Total Nitrogen (over 1 micromole)

and Total Phosphorus (over 0.1 micromoles). This means biological indicators such as benthic algae, fish

diversity and coral health may be more sensitive than water column nutrients for detecting eutrophication.

Although initial baseline water quality parameters are useful, the resources and expense of inorganic

nutrient content is not required when biological proxies can be used (e.g. benthic algae diversity, fish population

assessments or dissolved oxygen). Water quality was also measured continuously for temperature, salinity,

turbidity and dissolved oxygen via HACH DataSondes deployed at stations in Victoria Pond and the adjacent

Elizabeth Harbour. The information collected from the mapping and water quality monitoring was summarized

in box plots (Figure 9) and used to develop a nitrogen loading and flushing model for Victoria Pond. Nitrogen

loading was then correlated with areas of depressed dissolved oxygen (elevated BOD) and coastal hypoxia

events.

Marine Biotic Assessments

Many studies have stressed the importance of near shore marine communities as nursery or settlement

sites for fisheries target species. Shenker et al. (1993) determined that many commercially important groupers

and snappers need the shallow nursery areas adjacent to islands to complete their life cycle. The rapid

ecological assessment of the Victoria Pond environs focused on an assessment of the existing seagrass meadows

and mangroves, as well as quantitative surveys of benthic algae and fishes. Seagrasses were considered critical

to the assessment for signs of eutrophication based on past research (see Borum, 1985, LaPointe et al 1992;

Tomasko and LaPointe, 1991). Seagrasses in tropical oligotrophic lagoons are likely to become overgrown with

algae, produce fewer shoots and have a slower growth rate as a result of increased nutrient levels in the water

column. With extreme eutrophication, algae can proliferate in the water column and on the sea floor to exclude

seagrasses from nutrified areas (Lapointe, 1989, Fourqueren et al., 1993). The parameters measured in seagrass

beds were: number of seagrass shoots/unit area (shoots per square meters); number of seagrass blades/shoot;

percent epiphyte coverage on seagrass blades; and percent coverage of the bottom (seagrass, algae or sediment).

More algae and epiphytes on the seagrass can be an indication of nitrification in the area.

Within the first six years (by 2002), the Victoria Pond monitoring sites had degraded too much for diver

surveys, and seagrass cores were taken from a small boat to monitor the remaining shoots. Seagrass density,

average percent coverage of Thalassia blades by epiphytes, and algal cover were mapped for all sites where

seagrass was surveyed. The initial survey in 1996 showed high blade count, low epiphyte load and high

seagrass density in Victoria Pond. The greatest seagrass diversity was at in the middle of Victoria Lake where

all three seagrass species were well represented in 1998. The average maximum blade length per quadrat

ranged from 0.7 – 30.4 cm throughout the Pond and adjacent Harbour. Thalassia testudinum was the species

with the greatest density and longest blades. This changed dramatically in the 2002 seagrass surveys. Over the

past decade, the addition of new buildings and bulkheads around the Pond had reduced the fringing mangroves

to 40% of the Pond perimeter (Figure 10). Seagrass coverage dropped by 70%, blade length decreased,

epiphyte loading increased, and only one species of seagrass (Thalassia) was found in the Pond. These dramatic

changes in Victoria Pond are linked to loss of mangroves and sewage disposal into the water. Seagrass

coverage, health and diversity are measurable parameters and can be established as ecological goals for the

Victoria Pond restoration (Clarke and Green, 1988); and are linked to the health and diversity of fish

populations in The Bahamas (Nero and Sullivan Sealey, 2006;2007).

Reef fish assessments were carried out at patch reef sites selected from aerial photography adjacent to

the Pond and throughout Elizabeth Harbour. These patch reefs were selected to establish baseline information

on the diversity, abundance and size of fishes; not all reefs were known to yachtsmen and locals for fishing or

snorkeling. The reef sites were surveyed by the research team who, using the roving diver method for a thirty

minute survey, recorded abundance and estimated length of predatory fishes, such as various species of grunts,

snappers and groupers. The abundance of reef fish predators was low for five of the seven reefs. At each site,

only a single or few representative predatory species (snappers and groupers) were present. At least one Nassau

grouper was recorded at every site but these fishes were small, ranging from 15-25 cm in total length. The

highest numbers of Nassau grouper, Epinephelus striatus, and schoolmasters, Lutjanus apodus, were recorded at

reefs the furthest distance from Victoria Pond, this is also where the highest number of lobsters was observed.

A total of 110 fish species were observed according to roving diver surveys. A total of 87 hours were spent

surveying fishes. The trend over time (from 1996 to 2010) was a decrease in both the abundance and diversity

of fish, with the most marked decreases seen in the three patch reefs adjacent to the Pond. Juvenile spiny

lobsters (Palunirus argus) were initially very abundant both on the reefs in along mangrove prop roots and

under docks in the Pond, but disappeared after 2002. Lobsters were counted during t30-minute timed surveys.

In the 2010 surveys, two out of six patches only one lobster was observed, while in the remaining reefs had no

lobsters observed at all. It is interesting to note that there is no correlation between the area (size) of the reef

and lobster abundance; spiny lobsters are habitat generalists but respond rapidly to water quality changes. Fish

and lobster abundance are excellent indicators of coastal water quality and the effectiveness of restoration

efforts (Sullivan Sealey and Constantine, 2008).

After more than a decade of monitoring, it was clear that the restoration of Victoria Pond was the key

project as a demonstration on improving coastal management and linking activities on land to impacts on water

resources.

Construction Tasks to Re-establish flow and coastal buffer zones

Criteria for improvements listed by residents include: (a) seeing more fish and better circulation or flow

through the Pond, and (b) seeing more birds around the Pond. Although a local committee does organize trash

clean-ups, there is little understanding of how people and the mangroves should co-exist, or how mangroves can

protect shorelines, provide wildlife habitat, and process pollutants. The restoration methods developed and

reviewed by the local community include improving flow through the Pond, and increasing the aesthetics of the

Pond environs through four restoration tasks.

The Victoria Pond Restoration project was initiated in June 2009 with a Community Clean-up. Over a

period of one year, detailed restoration plans were developed for public review and implementation, based on

four major tasks (Figure 11). The four major construction tasks were identified as:

Task #1: FEBRUARY POINT CAUSEWAY (Table 3): Excavation and installation of culvert pipes in

causeway bisecting the pond east of Victoria Pond at February Point.

Task #2: EAST CANAL (aka Love Channel) RESTORATION OF MANGROVE CREEK (Table 4) :

Debris Removal and Sediment Removal of Open Culvert and Drainage Canal connecting Victoria Pond with

Back Pond, east of Queen’s Highway Loop in George Town, Great Exuma Island.

Task #3: VICTORIA POND WEST CANAL CREEK RESTORATION AND BRIDGE

CONSTRUCTION (Table 5): Debris Removal and Sediment Removal of Box Culvert connecting Victoria

Pond with Back Pond, west of Queen’s Highway Loop in George Town, Great Exuma.

Task #4: QUEENS HIGHWAY BOX CULVERT CLEARING (Table 6): Debris Removal and Repair of

Box Culvert Connecting Victoria Pond with Back Pond, Culvert Located beneath Queen’s Highway Loop in

George Town.

Each of the above tasks requires a construction component and a community or volunteer component, such as

replanting, and a stewardship component. Each task should have a measurable improvement on Victoria Pond water

quality and associated biological diversity. In addition, private land owners can improve their on-site sewage

disposal, and minimize land-based sources of pollution through an outreach campaign developed with the

Department of Environmental Health Services and the Ministry of Tourism. Throughout the project, government

agencies , residents, businesses and visitor all played a role in clean-up, replanting, providing services (such as

heavy equipment and trash containers).

RESTORATION PLANNING, POLICY IMPLICATIONS AND MEASURES OF SUCCESS

The Victoria Pond restoration project has been initiated to restore the function of mangrove wetlands to

a.) Improve near shore water quality and b.) Enhance coastal fish habitat, particularly for fish and spiny lobster.

Both of these objectives serve the economic and ecological needs of Great Exuma. The management of the

coastal zone can be a critical mechanism to protect not only biological diversity of species and natural

communities, but also ecological function of coastal environs (e.g. in seagrass meadows, as per Fourqueran et al,

1993).

Coastal buffer zones under the stewardship of local communities can protect mangrove systems, provide green

space, and limit the extent of coastal alterations, thus protecting near shore ecology. Although there are

international guidelines on coastal setbacks, these setbacks primarily apply to beach and dune systems. There are

few examples of coastal buffer zones established for other types of coastal habitats. People do not recognize the

connectivity between land and sea ecological systems, and thus often fail to see value of leaving a vegetation

buffer adjacent to mangroves, beaches or rocky shores.

Over the past decade, local governments in George Town managed Victoria Pond in an ad-hoc manner,

responding to short-term goals of restoring a “view of the water” from the roadway, or rapidly drain areas that

periodically flood, with no resources or technical assistance. Human communities require more tangible results to

support environmental management initiatives. Residents of George Town agree the Pond smells bad, and is not

attractive (refer to Table 1); local government must respond with some action, although that action is not vetted

for environmental regulatory compliance.

The coastal zone of small islands is critical to ecological function of island systems. The Victoria Pond

restoration project aims to better understand and demonstrate the ecosystem function provided by coastal buffer

zones, especially indicated by more abundant and diverse fish assemblages. There have been some

miscommunications about the coastal buffer zones; these are the first areas impacted by tourism and infrastructure

development on islands. The Bahamas is set apart from other Caribbean countries by the lack of an Integrated

Coastal Zone Management and Planning Unit (ICZM). The Coastal buffer zone is the functional use (and design)

of coastal setbacks to:

(a) Stabilize the coast, and protect property from storm surges and erosion,

(b) Allow the coastal buffer of natural vegetation to filter groundwater and storm run-off to prevent pollutants

from the development from entering the near shore marine environments, and

(c) Protect the native plant diversity on the island by allowing contiguous zones of native vegetation, with natural

topological gradients in the coastal dune and swale systems.

Recent legislation (2009) for sea turtle protection does make reference to protection of dunes and beach systems

used for turtle nesting, but do not address the coastal restoration and establishing of coastal setbacks. Although

buffer zones and setbacks are specifically mentioned in the National Wetland Policy (BEST 2007), there are few

guidelines for implementation or remediating historical or existing encroachments on fully-protected wetlands.

Several proposals were developed for funding the Victoria Pond Restoration Project in collaboration with the

Ministry of the Environment, the National Wetland Committee, Ministry of Tourism, and the Exuma Foundation.

A key goal of a public-private partnership for the restoration project is the ability to linked measured ecological

recovery to community actions. Funding will need to come from both public and private sources over many years

to complete the physical restoration and sustain with wetland stewardship activities. Only over time will the

economic benefits be apparent, and the rewards of coastal zone management realized.

The Bahamas has existing laws, policies and treaty commitments that present expectations for coastal zone and

wetland management, but lack incentives for immediate action. The National Wetland Policy’s stated purpose is

to provide one document that outlines the Government of The Bahamas’ position on wetland protection. The

policy applies across departments and agencies with any management or regulatory responsibility for land-use

planning, coastal and marina development, placement of septic systems or protection of marine resources

(National Wetland Policy, 2005). Only through on-the-ground demonstration projects like the efforts at Victoria

Pond will the value of these national policies be appreciated by local communities.

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discharge on coral reef regions. Water Science and Technology 21:121-130.

BEST. 2003. The National Invasive Species Strategy for The Bahamas. The Bahamas

Environment, Science and Technology (BEST) Commission, Ministry of Health and

Environment Nassau, The Bahamas. 34 pp.

BEST. 2007. The Bahamas National Wetland Policy. Ministry of the Environment, Bahamas

Environment, Science and Technology (BEST) Commission. 26 pp.

Borum, J. 1985. Development of epiphytic communities on eelgrass (Zostera marina) along a

nutrient gradient in a Danish estuary. Marine Biology 87:211-218.

Buchan, K.C. 2000. The Bahamas. Marine Pollution Bulletin Vol 41(Nos 1-6):94-111.

Burke, L. and J. Maidens. (2004). Reefs at Risk in the Caribbean. World Resources Institute,.

Washington, D.C. 126 pp.

Cant, R.V. 1997. Developing water supply strategies for the Bahamas. Bahamas Journal of

Science. 4(2):5-7

Chiappone, M, J. Kelly, E. Schmitt and K. Sullivan Sealey. 1999. Tools and Methods for

assessment of land-based sources of pollutants and their impacts on coral reefs. University of

Miami, Coral Gables, Florida. 132 pp.

Chiappone, M., and K. Sullivan- Sealey. 2000. Marine reserve design criteria and measures of

success: Lessons learned from the Exuma Cays Land and Sea Park, Bahamas. Bulletin of

Marine Science 66, no. 3 (2000): 691-705.

Clarke, K.R. and R.H. Green 1988. Statistical design and analysis for “biological effects” study.

Marine Ecology Progress Series 46: 213-226.

Cowardin, L. M., V. Carter, F. C. Golet, E. T. LaRoe. 1979. Classification of wetlands and

deepwater habitats of the United States. U. S. Department of the Interior, Fish and Wildlife

Service, Washington, D.C. 131pp.

Daily, G.C. 1997. Introduction: What are ecosystem services? Pages 1-10 in G. Daily, editor.

Nature's Services: Societal Dependence on Natural Ecosystems. Island Press, Washington, D.C

Department of Statistics, Government of The Bahamas. 2011. Preliminary population and

housing count by Island and Supervisory District. All Bahamas Census 2010. 3 pp.

Fourqurean, J.W., R.D. Jones, J.C. Zieman. 1993. Processes influencing water column nutrient

characteristics and phosphorus limitation of phytoplankton biomass in Florida Bay, Florida USA.

Inferences from Spatial Distributions, Estuarine and Coastal Shelf Science 36: 295-314.

LaPointe, B.E. 1989. Macroalgal populations and nutrient relations in oligotrophic areas of

Florida Bay. Bulletin of Marine Science 44:312-323

LaPointe, B.E., M.M. Littler and D.S. Littler. 1992. Modifications of benthic community

structure by natural eutrophication: the Belize Barrier Reef. Proceedings of the 7 th Internatioanl

Coral Reef Symposium, Guam, 1:323-334.

Madden, C. J., K. Goodin, R.J. Allee, G. Cicchetti, C. Moses, M. Finkbeiner, D.

Bamford, 2009. Coastal and Marine Ecological Classification Standard. NOAA and

NatureServe. 107 pp.

Nero, V.L. and K Sullivan Sealey. 2006. Fish-environment associations in coastal waters of

Andros Island, The Bahamas. Environmental Biology of Fishes 7, 223-236.

Nero, V.L. and K.M. Sullivan Sealey. 2007. Island Specific Responses of Bahamian Benthic

Flora to Environmental Features. Caribbean Journal of Science. 42 (3).

Paul, J.H., J.B. Rose, S. Jiang, C. Kellogg and E.A. Shinn. 1995. Occurrence of fecal indicator

bacteria in surface waters and the subsurface aquifer in Key Largo, Florida. Applied and

Environmental Microbiology 61:2235-2241.

Sluka, R., M. Chiappone, K. M. Sullivan, R. Wright. 1996. Habitat and life in the Exuma Cays,

The

Bahamas: The Status of Groupers and Coral Reefs in the Northern Cays. Media Publishing Ltd.,

Nassau, Bahamas. 83 pp.

Sullivan Sealey, K. 2000. Tourism and Water Quality in Elizabeth Harbour. Bahamas Journal of

Science Vol 7(2), May 2000: 2-19.

Sullivan Sealey, K. and N. Cushion. 2008. Efforts, Resources and Costs Required for Long-term

Environmental Management of a Resort Development: The Case of Baker’s Bay Golf and Ocean

Club, The Bahamas. Journal of Sustainable Tourism. Vol 16: 6.

Sullivan Sealey, K. and S. Constantine. 2008. Fish Fauna as Indicators of Coastal Restoration

Goals and Success. Proceedings of the 60th Gulf and Caribbean Fisheries Meeting, Punta Cana,

D.R. Nov 7-11, 2007: (60).

Sullivan Sealey, K.M. 2004. Large-scale ecological impacts of development on tropical islands

systems: Comparison of developed and undeveloped islands in the Central Bahamas. Bulletin of

Marne Science 75(2):295-320.

Tomasko, D.A. and B.E. LaPointe. 1991. Productivity and biomass of Thallassia tesudinum as

related to water column nutrient availability and epiphyte levels: Field observations and

experimental studies. Marine Ecology Progress Series 75:9-17.

ACKNOWLEDGEMENTS

Victoria Pond and Elizabeth Harbour research would not have been possible without the field assistance of

Elton Joseph, Alexio Brown, Nicholas Bernal, Kathleen Semon, Vanessa Nero McDonough, Emily Schmidt, Katia

Pronzati, Aimee Lowe, and Captain Susan Darcy Henry. Financial support for this research came from the

Earthwatch Institute “Coastal Ecology of The Bahamas” project, The Nature Conservancy, the late Samuel

Johnson, The Jeniam Foundation, and the University of Miami.

Figure 1: Map showing the location of Great Exuma in the central Bahamas. Elizabeth Harbour

is shown in green, and George Town is located on the island of Great Exuma in the middle of

Elizabeth Harbour. Victoria Pond is in the center of George Town.

Figure 2: George Town land ownership from 1890 and aerial view of George Town today .

Figure 3: Cut into Victoria Pond. In the 1800’s, a cut through the narrow limestone ridge allowed

small boats to enter Victoria Pond from Elizabeth Harbour. This photo looks to the southwest

into the pond. The cut allowed surface water exchange between the two marine lagoons. A

narrow stone bridge allows the main highway to pass through George Town across this cut. Note

the invasive Australian pines (Casuarina equestifolia) along the pond perimeter.

Figure 4: Flooding occurred on Exuma after Tropical Storm Noel in 2007. The filling in of

wetlands, and disruption of wetland systems by roads and coastal development exasterbated

the flooding. Additionally, the flood waters moved high nutrient- high sediment load run-off

into coastal lagoons, triggering a high BOD, and acute hypoxia.

Figure 4: Photo of intact coastal environments of Exuma illustrating mangrove pond and

adjacent clear near shore waters supporting patch reefs, seagrass meadows and sandy bottom

communities. Coastal management is important to support marine fisheries species production.

Figure 6: Map of the Victoria Pond Restoration Project area showing the ephemeral wetlands

that fill seasonally with fresh water (red), mangrove ponds (yellow) and adjacent Elizabeth

Harbour (green). Historic water flow has been disrupted by road construction and fill.

Figure 7: Illustration of tropical coastal eutrophication processes. The increased turbidity from

eutrophication is linked to loss of seagrass in tropical shallow water marine systems like Victoria

Pond.

Figure 8: The filled mangrove creek leading into Victoria Pond (Love Channel) was the site with

the worst water quality, lowest dissolved oxygen, and highest nitrogen loading. Photos illustrate

areas ranked “High to Severe” . The illegal dumping of trash into the wetland (A) and close

proximity of houses with cesspits to the waterway (B) along with the removal of mangroves and

coastal plants earned a rank of “Severe” impacts. The accumulation of anoxic sediment make

nutrient determination superfulous.

A.

B.

Figure 9: Box plots are used to illustrate patterns of variability in water quality paratmeters. A)

the annual pattern of temperature variability shows the mean monthly temperature in degrees

Celsius, but also the monthly variability. Winter and spring months have cooler but more

variable temperatures which can stress marine fish and invertebrates. Box plots for summer

Victoria Pond sampling across tidal and daily cycles are presented for B. dissoled oxygen (mg/l),

C. Salinity(ppt) and D. Temperature (degrees Celsius) for the seven water quality stations in and

around Victoria Pond. The Box Plots identify stations were hypoxia (low oxygen) occurs.

A

B

C

D

Figure 10: Photos of the alterations around the Victoria Pond in the 1990;s that contributed to

massive seagrass loss. Fringing mangroves were removed, and replaced by stone walls. Part of

the Victoria Pond restoration is aimed at adding rock rip0rap in front of the walls and re-planting

red mangroves in front of the walls.

Figure 11: Overview Diagram of the Victoria Pond Restoration Project. The major construction

tasks in the Victoria Pond restoration project will focus on re-establishing flow and fringing

mangrove communities.

Table 1: Symptoms of degradation or change in the Victoria Pond, Great Exuma coastal

environment: Some changes can be part of natural variation in ecological processes over time;

some changes can be attributed to human impacts on the coastal ecosystems. The methods

were designed to investigate these symptoms and report on the condition of marine resources

in the Harbour relating to water quality issues.

SYMPTOMS DESCRIPTION AND REPORTED EXTENT

Change in water color,

Decrease in water clarity;

Change in water to murky color and

greenish in appearance

Changes from “blue” water to greenish after

rainfall event

Less water clarity in areas adjacent to George

Town, off Regatta Point, Kidd Cove and Victoria

Pond.

Victoria Pond looks cloudy and “soupy green”

for weeks after storms

Fish kills in Victoria Pond Dead fish accumulated along the shoreline of

the Pond in late summer, and after flooding

events

Loss of wildlife around Victoria Pond Disappearance of tarpon and other large fishes

once seen from the docks in Victoria Pond

Increase in the number of upside down jelly fish

(Cassiopeia xamachana) around the pond, fewer

fish and disappearance of seagrass

No more wading birds around the Pond

No more schools of little fish, especially small

grunts around the Pond

Foul smell to water, especially in

summer

Victoria Lake and Kidd Cove area have “sewage”

or rotting smell, especially in summer at low

tide.

Shoreline of Victoria Pond and Kidd Cove

covered with filamentous green algae

Decrease in amount of live coral and

“color” on patch reefs in adjacent

Elizabeth Harbour

Decrease in the reefs both at the southeastern

end of the Harbour and patch reefs near Victoria

Pond

Decrease in the extent of coral growth

adjacent to coastline

Loss of coral patches in areas adjacent to

dredged channels and docks.

"smothering" of corals and patch reefs by

sediment from seagrass loss and run-off

Decrease in the number of adult

snappers on reefs within the Harbour

Recreational fishing pressure undocumented for

Harbour area, but reports of poor fishing

compared to 20+ years ago, fewer large fish seen

in Harbour, fewer fish in or adjacent to shoreline

in George Town

Table 2: Coastal plant communities found in and around George Town, Exuma environs.

A coastal natural community classification is important to understand the original

ecology of Great Exuma, and plan coastal restoration projects using native plant

assemblages.

MANGROVE WETLANDS

Fringing mangroves

Mangrove creeks and embayments

Mangrove ponds

BEACH STRAND COMMUNITIES

Low Profile Beach to Lowland Evergreen Shrubland

Low Profile Beach to Palm-dominated Lowland Shrubland

High Profile Beach to Sea Oats and Herb-dominated Shrubland

ROCKY SHORE COMMUNITIES

Windward Rocky Shore with wide long transition from woody herbs to lowland

shrubland

Leeward Rocky Shore with abrupt transition from woody herbs to lowland

shrubland

0

Table 3: The first task in the Victoria Pond restoration was improving flow through a causeway.

TASK #1 FEBRUARY POINT CAUSEWAY: Excavation and installation of culvert pipes in causeway bisecting the Back Pond east of Victoria Pond at February Point.

Ecological Objectives:

Improve water quality and increase fish population in the wetland system by restoring tidal water flow between Victoria Pond, the February Point Pond to the east and Elizabeth Harbour. This causeway has a single 24-inch culvert that restricts circulation through to Victoria Pond.

Construction Component

Excavation of causeway to accommodate installation of new culvert piping. Excavation material will be used as back fill material and compacted to ensure trafficability while minimizing erosion to the causeway.

Construction

Materials

Concrete culvert pipes, to be provided by the Ministry of Works

Days to complete task

3 days duration upon staging of culvert material on location.

Photos: Incoming

tide through small single culvert at

February Point Causeway (right) illustrates restricted

flow. The aerial diagram illustrates the location of new

culvert, and flow through to Victoria

Pond.

Baseline information Water quality monitoring, Benthic surveys, and fish surveys

Post restoration monitoring

Water quality monitoring, Benthic surveys and fish surveys. Monitoring will occur near the new causeway culverts

Priority HIGH

1

28

2

Table 4: The second task for the restoration project involves the filled wetlands behind mostly rental houses in George Town. The east canal area is

along Lovers Lane Court, and is referred to as the ghetto of George Town, “Ugly Corner” or “Love Channel”. This area presents the greatest public health risk with raw sewage entering the wetland system.

TASK #2 EAST CANAL (aka UGLY CORNER, LOVE CHANNEL) RESTORATION OF MANGROVE CREEK : Debris Removal and Sediment

Removal of Open Culvert and Drainage Canal connecting Victoria Pond with Back Pond, east of Queen’s Highway Loop in George Town, Great Exuma Island. Task includes:

Bank stabilization with boulders, rip-rap, and mangrove planting on both sides.

Removal and transplanting six coconut palms from the wetland buffer zone to off site.

Replanting wetland buffer zone with native plants.

Ecological Objectives

and Components:

Improve water quality and increase fish population in the wetland system by restoring tidal water flow between Victoria

Pond, the February Point Pond to the east and Elizabeth Harbour. This area is primarily filled wetland, thus fill will need to be removed, and the creek channel re-established. This site was the source area for documented cases of malaria; ideal conditions exist with residential dwellings close to accumulated trash and filled wetlands for pest mosquitos and other

disease vectors to propagate. Healthy wetland systems can eliminate the public health threat.

Construction Component

Description

Work will include:

Excavation and removal of trash, debris, accumulated bottom sediment, and spoils from reshaping the canal

embankments for line haul to the local waste management facility;

Transplanting of six mature coconut palms in the buffer zone to off site;

Placing rock revetments, and

Replanting mangroves, wetland reconstruction, and native plants in buffer zone. Due to proximity of commercial and residential facilities, overgrowth of foliage and sanitary conditions of the work site, work

efficiency will be impacted. Further impact will be encountered due to the close buildings when cleaning out the four-foot open concrete culvert (see photo) from the Queen’s Highway Loop eastward up the canal for a length of 178 feet.

Construction Materials

+/- 60 Inch Diameter Boulders, +/- 10 Inch Diameter Rip-Rap for stabilization of the embankments on both sides of the canal. Soil Stabilization will also be accomplished with the transplanting of Red, Black, and White Mangrove saplings. Further

protection of the new planted embankments will be accomplished with the planting of native plants fifteen feet out from the embankments to set a Wetlands Buffer Zone.

Days to complete

task

35 Contractor Days: 3 days to transplant six coconut palms off site. 12 days to remove and haul to waste management

facility an estimated 475 Cubic Yards of Sediment and Debris; 20 days to place an estimated 202 Cubic Yards of Boulders and 101 Cubic Yards of Rip-Rap for embankment stabilization and Mangrove Bedding Area.

20 Volunteer Days: For planting of embankments with Mangroves, and planting of Native Plant Buffer Zone.

Approximate cost Approximately $223,168 with some additional costs for large boulders

29

The narrow channelization and fill

in this area has caused both ecological degradation and

public health threats (left). Ugly Corner (right) is the focus of

additional project planning and

proposals to resolve the issues of sewage disposal

The restoration of the mangrove creek with

rock revetment channels will allow increased flow

through the Victoria Pond wetland system. This addition flushing

will support more mangrove diversity

(Red, black and white mangrove trees), improved wildlife

habitat.

30

East Canal of Victoria Pond (aka Ugly Corner)

has been the more challenging part of the restoration project.

Wetlands have been encroached by illegal dumping, sewage is

leaching into wetlands, and the area

is unsafe to work.

MARCH 2010 revetments installed at entrance

JUNE 2009 Excavation of trash from the canal

Baseline information Water quality stations at both ends of the channel, Sediment cores; It has not been possible to do fish surveys. Because of the sewage seepage into the wetlands, limited baseline research could be done

Post restoration monitoring

Water quality stations at both ends of the channel, Sediment cores, and fish surveys. Prior to restoration, it has not been possible to put researchers in the water.

Priority HIGH PRIORITY

3

4

31

5

Table 5: The third task in the restoration project involves improving the aesthetics of the Victoria Pond area, and making nature more accessible and attractive to the community.

TASK #3 VICTORIA POND WEST CANAL CREEK RESTORATION AND BRIDGE

CONSTRUCTION– Debris Removal and Sediment Removal of Box Culvert connecting Victoria Pond with Back Pond, west of Queen’s Highway Loop in

George Town, Great Exuma Island. Task includes

Removal 168 feet of culvert cover (timber planking) with 54 feet to be rebuilt as 4 wide deck plate covers,

Removal of 114 feet of the south culvert wall and opening the span of the canal to 16 feet,

Removal and replacement of concrete deck bridge with timber arch bridge constructed from recycled lumber,

bank stabilization with boulders and mortar,

Rip-rap and mangrove planting on the south side.

Landscaping with native plants in the wetland buffer zone on both sides of the canal and replacing the

block walls on the southern approach walkway to the canal pedestrian bridge (Timber Bridge).

Ecological Objectives and Components:

Improve water quality and increase fish population in the wetland system by restoring tidal water flow between Victoria Pond, the February Point Pond to the east and Elizabeth Harbour. This area is primarily filled wetland, thus fill will need to be removed, and the creek channel re-established.

Construction Component Description

Removal of the box culvert cover (timber planking) will be done in such a matter as to allow reuse of the material for both the construction of new culvert deck plates and in the construction of the Timber Arch Bridge. Excavation and removal of trash, debris, accumulated bottom sediment, and spoils from reshaping the canal

embankment for line haul to the local waste management facility. With the proximity of a commercial property and the public park, work efficiency will be impacted due to the restricted area for the earth moving equipment

to operate as well as limited area for staging of debris for line haul and the staging of construction material upon completion of demolition and excavation. Following compaction of the new 2:1 slope of south embankment, installation of +/- 30 Inch boulders will be set with mortar for stabilizing the lower third of the

new embankment. The upper two thirds of the embankment will be stabilized with +/- 30 Inch boulders with 10 foot wide revetments constructed of +/- 10 Inch diameter Rip-Rap spaced every 20 feet for planting of Mangrove saplings. Construction of Timber Arch Bridge from recycled lumber, as well as repairing 54 feet of

culvert cover with recycled timber from the old cover.

Construction Materials +/- 30 Inch Diameter Boulders, +/- 10 Inch Diameter Rip-Rap for stabilization of the embankment on the south side of the canal. Soil Stabilization will also be accomplished with the transplanting of Red, Black, and White

Mangrove saplings. Further protection of the new planted embankments will be accomplished with the planting of native plants eight fifteen feet out from the embankments to set a Wetlands Buffer Zone. Timber

Bridge: 2 X 14, 2 X6, 2 X 4, and 4 X 4 TIMBER; 6 Cubic Yards of 3,000 psi concrete; 200 lineal feet of #5 vinyl coated reinforcing steel; and stainless steel fasteners. 2 x 6 culvert cover planking will be reutilized to replace 54 linear feet of culvert cover with 4 foot wide cover plates constructed with 16d stainless steel nails.

32

Days to complete task 18 Contractor Days: 5 days to remove and haul to waste management facility an estimated 264 Cubic Yards of Sediment and Debris; 8 days to place an estimated 66 Cubic Yards of Boulders and 34 Cubic Yards of Rip-Rap for

embankment stabilization and Mangrove Bedding Area. 12 Volunteer Days: For planting of embankments with Mangroves, and planting of Native Plant Buffer Zone.

Approximate cost Approximately $81,791, to used recycled materials and timber when possible.

PHOTOS and drawings Show

the area adjacent to the public park with wood-covered

channel. The mangrove creek will be opened and a wooden bridge will replace the current

walkway.

33

Overview diagram

34

The

wooden foot bridge and vegetated buffer zone can add

scenic views and wildlife habitat back to Victoria Pond. The Park area can be enhanced

with interpretive signs and planted with trees suitable to grow on fill.

35

Victoria Pond western canal area will include an expansion

of the mangrove creek, repairing and leaving some of the wood covering, and adding

a wooden foot bridge over the restored mangroves.

Baseline information Three water quality stations around Victoria Pond, 10 years of seagrass assessment in the Pond, Fish surveys from 1996 to 2002, water was too turbid and polluted for fish surveys after 2002.

Post restoration monitoring Water quality stations (three around the Pond and in the western canal; sediment cores. Seagrass and fish

surveys will resume after water quality improved (one year after Phase 1 restoration).

Priority HIGH

6

7

36

8

Table 6: The fourth and last task in the restoration project involves correcting past “design flaws” in the box culvert used to direct water under the

main highway through George Town. This culvert was not designed to protect the wetlands, and was not maintained, thus years of trash and debris were allowed to accumulate under the road. This task should especially impress the local community on the cost of restoration compared to the cost of coastal stewardship and prevention.

TASK #4 QUEENS HIGHWAY BOX CULVERT CLEARING: Debris Removal and Repair of Box Culvert Connecting Victoria Pond with Back Pond, Culvert Located beneath Queen’s Highway Loop in George Town, Great Exuma Island.

Ecological

Objectives and Components:

Improve water quality and increase fish population in the wetland system by restoring tidal water flow between Victoria Pond, the

February Point Pond to the east and Elizabeth Harbour. The road box culvert is the most restricted area for flow in the wetland system.

Construction Component Description

Remove remnants of two 20 inch culvert pipes that were left in place during earlier retrofit replacement with a 4 Foot by 4 Foot box culvert. Removal process to include removal of 43 linear feet of impacted debris built up in the box culvert beneath Queens Highway due to flow restriction caused by the sediment filled culvert pipes. With 43 feet of the 53 foot culvert crossing completely filled with

debris, the restoration process requires removing the asphalt roadway and culvert concrete cap across the entire 53 foot span to effectively remove the debris and repair the east end of the box culvert to replace the two 20 inch pipe culverts. Debris removal is estimated at 48 cubic yards for removal and hauling to local waste management facility. Constraints to the project are: a 4 inch city

water main crossing over the east end of the culvert and associated residential water line in the same proximity, requiring the assistance of the local water service department during excavation and subsequent repairs to the box culvert and roadway; the second

constraint is the daily traffic requirement of this one way traffic loop to commercial, housing, and harbor business areas, which will necessitate providing one lane access with steel plate covering over the excavation and traffic control to ensure a safe and orderly construction site. Box Culvert side wall repairs will be determined upon complete excavation of the road crossing. Upon completion

of any and all necessary repairs to the box culvert a steel reinforced concrete cap will placed over the culvert and subsequently covered with a bituminous roadway surface to match the existing highway surface.

Construction

Materials

Bituminous Asphalt Roadway Surface estimated at 7 Cubic Yards. Concrete Cap estimated at 13 Cubic Yards with an estimate of 814

Lineal Feet of No. 10 Reinforcing Steel Bar. Reinforced Concrete estimates for the Box Culvert side walls will be estimated upon completion of project excavation.

Days to

complete task

Estimated at 15 Labor Days to include: 3 days excavating road surface and concrete cap; 2 days to excavate and haul debris, 10 labor

days anticipated to repair sidewalls and replace concrete cap/road surface. This estimate does not include non-labor duration days for concrete curing.

Approximate

cost

$50,035: Excavation and Disposal ($19,035); Concrete Cap & Road Surface Replacement ($16,000); Contingent Box Culver Repairs

($15,000)

37

PHOTOS and drawings

Scope of work for the repair of the box culvert includes

removing concrete and pavement cap, then

clearing the debris clogging the culvert. Pipes are the eastern

end of the culvert require repair. Water main running along the

road would need to be installed to the

satisfaction of the Water and Sewage Corporation.

Baseline information Three water quality stations around Victoria Pond, 10 years of seagrass assessment in the Pond, Fish surveys from 1996 to 2002, water was too turbid and polluted for fish surveys after 2002.

Post restoration

monitoring

Water quality stations (three around the Pond and in the western canal; sediment cores. Seagrass and fish surveys will

resume after water quality improved (one year after Phase 1 restoration).

Priority MEDIUM

9