JUNE 15, 2000

How is Narragansett Bay doing today? It seems like a simple enough question, but there is no one single answer. The Bay is valuable in many ways – as a natural habitat, a workplace, a recreational treasure, and as a wonderful place to live. How well it is doing depends on the standard for comparison. This report provides a simple, practical, and up-to-date overview of the Bay’s condition and what can be done to improve it.

When we speak about the “state of the Bay,” we are referring to its ecological health. At Save The Bay, we measure progress in cleaning up the Bay and preventing pollution based on data and observations, collected over time, from a wide range of sources. We consider major trends in water quality, species diversity and abundance, and the existence and severity of environmental or human health risks.

For this report, we have selected ten categories, each of which we believe is indicative of the Bay’s overall environmental health. Ratings were assigned on a scale of 1 to 10, with 10 being the healthiest Bay we can imagine, and 1 being the worst, most polluted or degraded condition we can imagine. The numbers ultimately represent Save The Bay’s level of concern in each of these areas – a low score indicates a more serious concern These ratings were based on:

  • Available data from Bay-related research, including historic records, scientific and academic publications;
  •  Results of Save The Bay’s own staff and volunteer monitoring; and,
  • Interviews and informal surveys with local knowledgeable persons in each category.

This report was developed to educate the public – including our children – about the health of Narragansett Bay. What we have come to more fully understand in preparing this report is that Narragansett Bay is in trouble. While many people marvel at how much “cleaner” the Bay looks, many of our indicators evidence serious problems. But, by facing these problems and taking action to solve them, we also have reason to believe that we can turn the tide. This report illustrates the most significant challenges and opportunities we have to save the Bay.

Nutrients Rating: 3 of 10

Nutrients such as nitrogen and phosphorus are essential for the plankton growth that forms the basis of the Bay's food web. They enter the Bay through fresh water rivers, the atmosphere, and the rich ocean currents from Rhode Island Sound. When in balance, nitrogen and phosphorus are a key to making the Bay productive.

Situation Update: Excessive nutrients from wastewater treatment plants, septic leach fields, and polluted runoff have upset the natural balance in the Bay. It is estimated that human activities have increased nitrogen levels in the Bay by five times the historic levels. In recent years, nutrient overloading has caused massive algae blooms which cloud the water during spring and summer. Blooms make the water murky, which can shade and kill valuable underwater grasses such as eelgrass that depend on sunlight to live. As the algae and plankton die, they settle to the bottom and decompose, a process which robs the water of life-giving dissolved oxygen (see dissolved oxygen indicator below for more detail). Historically, broad areas of the Bay bottom were covered with seagrasses and other ecologically valuable plants. Today, it is dominated by nuisance seaweed and algae like sea lettuce which can tolerate nutrient pollution.

Recommendation: We must take immediate steps to reduce nutrients from wastewater and polluted runoff. Advanced technology exists to remove nutrients at wastewater treatment plants and reduce nutrient pollution from septic systems. Existing treatment plants can take relatively simple and inexpensive steps to reduce nutrients. This technology must be implemented throughout the region to reverse the trend of nutrient over-enrichment presently growing in the Bay.

Dissolved Oxygen Rating: 3 of 10

Dissolved in the water, oxygen is required by nearly all species of marine life. Maintaining a healthy level of oxygen in the Bay is critical to the survival of fish, shellfish, lobsters and marine plants.

Situation Update: Related to the problem of nutrient pollution is the occurrence of "hypoxia" – dangerously low oxygen conditions occurring in the Bay’s shallow coves and in the deep water near the bottom. Hypoxia has been well-documented in the Providence River shipping channel, and in portions of Greenwich and Mount Hope Bays since the early 1970's. Recent data indicates that the extent of the problem is greater than previously believed. In 1998 and 1999, near hypoxic conditions were recorded in deep parts of mid and upper Bay extending as far south as the West Passage. Data from sediment samples provides evidence that hypoxic events are occurring more frequently, and that these may affect the species makeup of the Bay bottom community. Sensitive species – that cannot tolerate the lack of oxygen – such as young fish, scallops, sea urchins, and some crabs are disappearing and being replaced by hardier, more pollution-tolerant marine life including worms, small clams, and spider crabs, for example.

Recommendation: Once again, nutrient pollution is thought by many to be a significant part of the picture. By reducing nitrogen and phosphorus inputs to the Bay, we may be able to better control the algae blooms that are linked to low oxygen conditions. Other nearby regions including Long Island Sound have severe low oxygen problems. Prompt action, described in the nutrient section above, is needed to reverse this impact.

Indicator: Eelgrass Rating: 2 of 10

Eelgrass beds are one of the most diverse and productive underwater habitats found in the North America and Europe. Eelgrass, or Zostera marina, one of approximately 50 kinds of seagrasses, is a flowering marine plant that lives completely underwater, rooted in the bottom. The long, slender blades provide critical habitat to scallops, juvenile winter flounder and many other important species of marine life.

Situation Update: Of all the coastal habitat types critical to the health of Narragansett Bay, eelgrass is in the greatest peril. It is estimated that the majority of historic eelgrass beds in Narragansett Bay have been lost. While historic records are incomplete, it is estimated that eelgrass once covered broad areas of the Bay bottom, potentially amounting to hundreds of acres. Today, less than one hundred acres remain. Eelgrass beds are a primary source of food and shelter to diverse marine life including economically important fish and shellfish species, such as the bay scallop. A major historic scallop fishery in the Bay has gone virtually extinct with the disappearance of eelgrass.  Because it is so dependent on clean, clear water, the status of Narragansett Bay’s eelgrass is a good indicator of the estuary’s overall health. Today, the greatest threat to eelgrass beds is poor water clarity caused by nutrient pollution. Other limiting factors include hurricanes and the wasting disease known to have decimated beds in the Bay in the 1930’s and which persists today.

Recommendation: Although water quality has improved in some areas of the Bay that used to support eelgrass, it is not expected to return without active restoration efforts. A combination of nutrient reductions and large-scale dedicated eelgrass restoration efforts are needed immediately to preserve and extend what remains in Narragansett Bay. Policy and regulatory changes are needed to control impacts from coastal development and other activities that damage eelgrass beds. In other areas of the country such as the Chesapeake Bay and Tampa Bay, Florida, seagrasses have been successfully restored.

Indicator: Toxic Substances Rating: 6 of 10

Toxic substances include heavy metals such as mercury, cadmium, copper, and lead; they also include chlorine, petroleum hydrocarbons, polychlorinated biphenyls (PCBs), pesticides, and other chemicals. All of these are considered harmful to human health and the environment at certain levels.

Situation Update: The lack of information about toxins in the Bay environment is problematic and must be addressed. Thanks to stricter laws and regulations, conventional sources such as industrial facilities and wastewater treatment plants have dramatically reduced the amount of toxic substances discharged to the Bay. Since 1983, municipal sewage treatment plants have reduced their toxic releases to the Bay by more than 90 percent by implementing stricter pre-treatment standards on commercial and industrial waste producers before they discharge to the sewer system. Today, only a few small portions of Narragansett Bay and the Upper Providence River are known to be contaminated enough to pose direct threats to human or environmental health. However, many toxic contaminants in wastewater are not routinely monitored by government agencies. The extent of contamination in Bay fish and shellfish has not been well studied or publicized. Areas of contaminated sediments lying undisturbed in the Bay bottom may not currently pose a threat to Bay health, but could cause problems if released by dredging, hurricanes or other disturbances.

Recommendation: Careful and comprehensive testing of fish, shellfish and sediments in the Bay and the rivers and streams in its watershed should be initiated. The results of this monitoring will determine what additional steps need to be taken to reduce toxins in the Bay environment. A management and remediation plan should address priority sites, identified by the monitoring, that pose the greatest risk to human and environmental health.

Bottom Fish Rating: 2 of 10

Bottom fish are year-round residents of Narragansett Bay which spend most of their time near or in contact with the Bay bottom.

Situation Update: Winter flounder and tautog have historically been among the most commercially and recreationally important species in Narragansett Bay. They also are particularly good indicators of its ecological health because they are directly dependent on the Bay for spawning and foraging habitat. In addition, their migratory patterns are relatively localized as they spend the majority of their lives in and around Narragansett Bay. Since the mid-1980's, both species have declined to historic low levels in the Bay, unfortunately paralleling a similar trend observed throughout the Northeast. Reasons for the decline are not fully understood, although overfishing, habitat degradation, milder winters, power plant impacts, and nutrient pollution have all been suggested as likely causes. All may have played a role in the significant decline over the last two decades.

Recommendation: Prohibitions on fishing for winter flounder and tautog may be needed to prevent the further decline and allow stocks to rebound. These should be coupled with efforts to address habitat degradation and other stresses, (including nutrients) to the Bay ecosystem.

Migratory Fish Rating: 6 of 10

Migratory fish include those that occur in the Bay from spring through fall, but which migrate along the Atlantic Coast. Species include Atlantic herring, striped bass, bluefish, squeteague, alewives, anchovies, and hickory shad, as well as many others. Generally, these fish swim in schools along the surface and middle of the water column, as opposed to "bottom" fish that spend most of their time near or in contact with the bottom.

Situation Update: While most bottom fish species have shown a downward trend in recent years, many migratory fish such as herring, striped bass, alewives, anchovies, and hickory shad have been increasing in abundance. However, habitat loss is still a major factor limiting alewives, herring and other anadromous fish runs (species that live in the ocean but migrate into fresh water rivers to spawn) from making a full recovery. These fish can reach spawning grounds in only 16 of 53 historic runs in the Narragansett Bay Watershed. Once great Atlantic salmon runs have gone extinct in Narragansett Bay. Recreational fishermen have celebrated the return of striped bass, which almost disappeared in the Bay in the mid-1980's. Great schools of large menhaden are much less frequent in the Bay now than during the 70's and 80's, but juveniles have been migrating into the Bay in increasing numbers during summer. Reasons for the increase are not fully understood, but menhaden, alewives, herring, and silverside minnows may actually be benefiting from the nutrient enrichment and algae blooms, as plankton is their primary food source. However, these species are not as commercially valuable as the bottom fish species. The return of striped bass should be viewed as a success story in fisheries management. It is likely, though, that environmental conditions have changed to the benefit of these species. Small "bait" fish exploit the excess plankton associated with blooms, and in turn feed migratory fish.

Recommendation: Despite gains we have made in these resources, migratory fish must be strictly managed to sustain healthy populations. Ninety-one percent of Narragansett Bay’s historic fish runs are in need of restoration including the installation of fish ladders and the removal of obsolete dams that block migrating fish. Federal matching funds may be available to the state for fish run restoration.

Salt Marshes/Coastal Wetlands Rating: 4 of 10

Salt marshes and coastal wetlands include the low-lying grassy areas flooded by the tide. These are among the Bay's most valuable-and most threatened-habitats. They serve as a nursery and spawning ground for 63 species of fish in Narragansett Bay, and act to stabilize the shoreline and buffer the effects of storms and polluted runoff.

Situation Update: An exact figure of the extent of salt marsh destruction since European settlement is not known, but consider that much of downtown Providence and Quonset Point are built on filled coastal wetlands. Furthermore, between 1955 and 1964, ten percent of coastal wetlands in Rhode Island larger than 40 acres in size were filled for property development. The 1996 aerial photographs of coastal resource areas in Narragansett Bay found that there are 3738.8 acres of salt marsh remaining in Narragansett Bay (Rhode Island Department of Environmental Management, Narragansett Bay Estuary Program and Save the Bay, 1999). It is estimated that Rhode Island has lost about half of the coastal wetlands since European colonization. Of the remaining salt marshes in the Bay, 70 percent suffer from restricted tidal flow, 60 percent are impacted by dumping and filling activities.

Recommendation: Sound conservation measures and active restoration efforts will be necessary to reverse these trends. First, we must prevent any further losses of marshes and coastal wetlands. Then a dedicated state program to restore the remaining marshes through actions such as removing tidal restrictions must be implemented.

Marine Mammals Rating: 7 of 10

Marine mammals that use the Bay include harbor seals, harp seals, Atlantic white-sided dolphin, harbor porpoises, pilot and other whales.

Situation Update: Historical records indicate that whales were once so common in the Bay and off of Rhode Island’s south coast that they supported a small whaling fleet based out of Newport. Though populations dwindled into the late 20th century, they have begun to rebound in recent years. Populations of harbor seals, as well as harp seals, Atlantic white-sided dolphin, harbor porpoises, pilot whales, and other whales have been observed in increasing numbers since 1990. Harbor Seals in particular are making a strong comeback and can be observed in herds as large as 100 at some 20 haul-out sites Baywide. Save The Bay’s seal monitoring program estimates the total harbor seal population between 225 and 275. Theories about why the seal population is growing include rises in the number of herring, a primary food source, and the Marine Mammal Protection Act of 1972, which prohibited hunting of seals.

Recommendation: Go out and see these magnificent creatures for yourself! Winter wildlife watching trips reveal a perspective on the Bay that many people have never seen. Be sure not to come too close to the seals – keep back by at least 500 feet to be safe – as they are easily disturbed.

Harmful Bacteria/Pathogens Rating: 6 of 10

The conventional measure of pollution in the marine environment is the presence of bacteria associated with human sewage. The intestinal coliform bacteria, E. coli, can indicate recent releases of untreated wastewater. Harmful organisms associated with sewage include many different bacteria, viruses, and other critters that may cause infections in swimmers or consumers of contaminated fish or shellfish.

Situation Update: During periods of heavy rain, stormwater running over the land combines with wastewater in sewers. This rush of water overwhelms treatment plants, forcing them to bypass or overflow raw or partially treated wastewater into the Bay. This leads to closure of swimming and shellfishing areas.Over 42,000 (30 percent) acres of Rhode Island’s shellfish beds are either permanently or partially closed due to sewage related contamination from inadequately disinfected wastewater, combined sewer overflows and non-point source pollution. Bacteria levels in the Upper Bay are decreasing thanks to improved wastewater treatment, but levels in the Lower Bay are increasing due to development pressures and failing septic systems.

Recommendation: Rhode Island has been ordered by the United States Environmental Protection Agency to address the problem of combined sewer overflows, a major contributor of sewage contamination to the Bay. Plans have been approved to begin a major infrastructure project to construct tunnels to store excess wastewater during storms to prevent overflows into the Bay. By moving quickly to implement this plan, we may be able to extend safe swimming and shellfishing areas into the Upper Bay and Providence River. Additionally, municipalities must repair and maintain aging sewage collection systems to ensure proper treatment. Communities should adopt wastewater management districts to ensure homeowners inspect and maintain their septic systems.

Shellfish Rating 6 out of 10

Shellfish of Narragansett Bay include quahogs, oysters, soft-shelled clams, scallops, mussels, whelks, and others.

Situation Update: Commercial landings of quahogs in Narragansett Bay declined from more than 2.5 million pounds in 1988 to less than 100,000 pounds in 1998 (National Marine Fisheries Service data, 2000). Much of this decline is due to overexploitation of the limited areas of the Bay which remain open to shellfishing year-round. Habitat and production for quahogs is still considered to be good throughout much of their traditional range. Scallops have declined precipitously since the late 1970’s, and are now scarce. The disappearance of eelgrass, their preferred habitat, is cited as one reason for the decline. Oysters began a resurgence in 1991, and have extended their range from the South County coastal ponds throughout the Bay and into the Providence River. They can even be seen as far north as Waterplace Park.

Recommendation: The Bay remains a productive shellfish habitat, but tighter management controls will be necessary to allow populations to recover. Several steps are needed: Sewer overflows must be curbed to reopen closed areas, nutrient pollution must be reduced, and eelgrass must be restored to bring back favorable habitat conditions for all shellfish. A state management plan that includes all of these elements would be a strong first step. In the interim, hard clam transplants from impacted areas help to sustain the fishery and may help keep stocks established throughout the Bay.


Overall Score: 4.5

A score of 4.5 indicates that the Bay is a long way from clean and healthy. While some of the historic industrial pollution problems are on the mend, nutrient pollution is getting worse, certain fish are at historic lows, and habitat is disappearing at an alarming rate. All of this may be exacerbated by the problem of global warming, which has been observed in Narragansett Bay through three decades of milder winters and hotter summers. Though factors like this may seem beyond our control, there is much that we can do to relieve the pressure on the Bay. By reducing nutrients, restoring habitat, and better managing our natural resources we help bring the Bay back to its full potential for everyone to enjoy.

A critical first step is to establish a fully-funded state habitat restoration program to address problems of nutrient pollution, and the loss of eelgrass, fish run and salt marsh habitat. As of April 2000, bills to establish such a program are pending before the Rhode Island General Assembly. Save The Bay recommends passage of these bills to establish a state habitat restoration program as the most important step we can take this year to improve the state of Narragansett Bay.