For Release: July 24, 1998

Contact: Bob Ballou, DEM 222-4700 ext. 4420

Chris Turner, DEM 222-3961 ext. 7229

Dr. Scott Nixon, URI 874-6800

DEM AND URI SCIENTISTS EVALUATE WATER QUALITY PROBLEMS IN NARRAGANSETT BAY

PROVIDENCE - Following the spate of recent beach and shellfish area closures in the upper and middle portions of Narragansett Bay, marine scientists at the Department of Environmental Management and the University of Rhode Island have been intensifying their efforts to assess water quality conditions in the Bay. According to the scientists, if historical patterns hold true, the unusual weather of early 1998, featuring high rainfall and warm temperatures, will likely result in localized fish kills, noxious odors, and discolored water in the Bay.

"We're expecting to see more of the type of local water quality problems that have occurred recently in portions of Greenwich Bay," said DEM Director, Andy McLeod. "We're monitoring problem areas so we can evaluate conditions and identify and address sources of pollution. And we're asking Rhode Islanders to let us know when they see fish kills or other environmental problems, so that we have a complete picture of the situation in the Bay."

The exceptional rains of June washed large quantities of bacteria- and nutrient-laden runoff into Narragansett Bay-namely sewage from overflowing wastewater systems, along with a variety of other fertilizing wastes, from lawn chemicals to pet wastes. The elevated bacteria levels forced DEM to close an extended portion of the upper and middle Bay to shellfishing and further prompted the Department of Health to recommend the closing of several public beaches in the area. Now, following the reopening of those shellfish and beach areas (only Warren Town Beach remains closed to swimming at this point), attention has turned to the high nutrient inputs and their effect on the Bay.

Nutrients, particularly nitrogen compounds, stimulate explosive growth or "blooms" of marine algae. According to Dr. Scott Nixon, a professor of oceanography at URI , "the respiration of the algae draws oxygen out of the water." When the algae become so dense that the oxygen in the water cannot support their respiration, the algae die off. The dead algae then decompose, robbing more oxygen from the water, leading to hypoxia-low-oxygen conditions-or anoxia, where the oxygen level in the water is essentially zero. Warm, calm weather exacerbates the problem by reducing wind-driven mixing and oxygenation.

The cycle of algal growth and death can cause discoloration of the water and foul odors like those reported in Greenwich Bay last week. Anoxia and hypoxia cause fish kills. While larger fish tend to swim away from anoxic waters, shellfish and small finfish cannot escape easily and so are more likely to die. Menhaden, small winter flounder, butterfish and crabs have been killed during past anoxic events in Narragansett Bay.

Low-oxygen conditions have been observed this summer at a number of locations around Narragansett Bay. DEM scientists have observed hypoxia in the Providence and Seekonk Rivers-not uncommon for these relatively polluted areas of the Bay. However, hypoxia has also been seen in areas where it does not normally occur: Belchers Cove in Warren; the West Passage off North Kingstown; and north of Prudence Island. These observations suggest that low-oxygen conditions will be more frequent and will affect a greater area of Narragansett Bay this summer than is typically the case.

Odors, fish kills and other effects of algae blooms and anoxia will be most pronounced-and most noticeable to boaters and beachgoers-in poorly flushed, heavily developed embayments like Greenwich Bay. However, low-oxygen conditions are likely to affect deeper areas of the middle and upper reaches of Narragansett Bay as well, stressing or killing bottom-dwelling animals like shrimp and crabs. Interestingly, quahaugs are usually hardy enough to endure brief periods with little or no oxygen; this important resource, therefore, will probably not be affected by the anticipated events.

While low-oxygen conditions occur to a limited extent in Narragansett Bay during most summers, wet springs and warm summers have, in the past, led to above-normal incidences of these problems. The summers of 1988, 1991 and 1992 saw widespread low-oxygen conditions in Narragansett Bay. Anoxic events are well documented in Long Island Sound and off the New Jersey coast. A hypoxia "dead zone" of several thousand square miles has become an annual problem in the Gulf of Mexico, linked to warm temperatures and large flows of nutrient-laden fresh water from the Mississippi River. And scientists have recently observed conditions in Massachusetts Bay that are not dissimilar from those here in Narragansett Bay.

The underlying cause of the problem is nutrient pollution from human settlement and development. Said Nixon, "I don't think this happened in Greenwich Bay before the late 1800s," i.e., before the region's coastal population started to swell and sewer systems began discharging to the Bay. Nixon added that "nutrient control is essential in order to reduce the incidence and severity of anoxic events in Narragansett Bay."

DEM is working on several fronts to reduce nutrient pollution on the Bay: facilitating the upgrade of wastewater treatment plants on the Providence River; using a watershed approach to address stormwater runoff; and, through the Narragansett Bay Estuary Program, assisting communities to identify and eliminate pollutant sources. However, pollution impacts triggered by truly exceptional weather-like the record-setting rains of June-will prove difficult to fully control.

Earlier this month, DEM also released a report titled "Narragansett Bay Water Quality: Status and Trends." The 20-page report, the first in a series of "state of the environment" reports prepared by DEM for the Governor's Advisory Council on the Environment, addresses 25 years of state and federal clean water laws, the profound improvements in Narragansett Bay's water quality in that time, what still needs to be done, and new approaches open to individuals, communities, and DEM to solve remaining water quality problems-including the nutrient-enrichment problems that are currently impacting the Bay. The report is available through DEM's Office of Technical and Customer Assistance by calling 222-6800 and it is also available on DEM's website at www.dem.state.ri.us.

To report water quality problems or for more information on water quality issues, call Chris Turner at DEM's Office of Water Resources at 222-3961 ext. 7229. (DEM's TDD line for the hearing impaired is 222-4462.)