Narragansett Bay: A Friend's Perspective
Rhode Islanders want the shores and waters of their Bay to look attractive and offer no offense to the senses. They have shown increasingly that they will fight hard and tolerate considerable denial of traditional property rights to achieve this goal.
There were attempts to construct oil refineries along the shores of the Bay, but there are none today because of overwhelming citizen opposition. An anti-litter campaign as strongly launched as its equivalent on land has boat owners bagging their garbage and personal debris to carry ashore for disposal. Some of the garbage might be completely biodegradable and food for the sea gulls and the hungry creatures beneath the surface, but into the plastic bag it goes. These concerns from citizens may often be based on aesthetics rather than on scientific fact, but they are instrumental in hitting at more important environmental dangers. Oil refineries bring oil tankers in large numbers and increase the chances of oil spills, which do cause considerable damage to fish and wildlife, muck up recreational beaches, and coat pleasure boats with a greasy film. They withdraw millions of gallons of fresh water from the ground or surface impoundments for processing.
The feelings against litter and dirty water, of course, are substantiated by the scientific community. Their studies show that pollution can be tolerated only to a degree. Once oxygen levels diminish and thick layers of sludge containing heavy metals, pesticides, and hydrocarbons build up, normal living forms in the water or on the bottom die or become sickly and, possibly, dangerous to the health of those who eat them.
However, when nuclear power plants and liquefied natural gas storage facilities are proposed, questions of human health and safety are paramount. In the late summer of 1977, the Federal Power Commission began to look at excess Navy land on Prudence Island as a site for liquefied natural gas storage tanks. Natural gas from Algeria, held in liquid form at temperatures more than 200 degrees below zero, is part of the energy equation in the minds of many utility engineers and economists. Prudence, with deep water suitable for large vessels around its southerly end, was being
The cure is to rip up the streets and install a separate network of pipes to handle storm runoff—a job so expensive and so disruptive of city life that most officials turn their backs on the problem. Yet ever so slowly a degree of separation is beginning to take place. As various sections of the city are redeveloped and streets and buildings reconstructed, separate storm sewers are installed.
It would have been far easier and infinitely less costly if Samuel Merrill Gray in 1884 had foreseen the problem. In that year, Gray, the city engineer, and his assistant, Charles H. Swan, went to Europe to investigate techniques for collect-in" and treating sewage. His voluminous report, based on visits to London, Paris, Berlin, Amsterdam, Danzig, Milan, and various other cities, brought about construction of the first plant. Some 50 miles of sewer lines had already existed, leading to outfalls in the river. Complaints about noxious odors and the physical evidence of dying oyster beds in the upper river had led the city council to conclude that something should be done about the problem. There was concern at the time that the foul smells and the gases rising from the water might cause typhoid fever and cholera.
The problem of combined storm and sanitary sewers aside, Gray designed a good system, capable of handling the wastes of a city of 300,000 persons. He favored the use of irrigation, the spreading of wastes over hundreds of acres of land to permit the earth to act as a filter, but realized that sufficient land was not available. So he recommended the use of chemicals to precipitate the suspended solids out of the sewage and to clarify the final effluent. He set out floats on the surface of the river, and calculated flow patterns the treated effluent would take by observing the movement of his floats.
He also identified manufacturing wastes as special offenders—"upwards of 2,735,000 gallons of filthy liquid wastes" daily in the Moshassuck and 2,088,000 gallons in the Woonasquatucket—and designed his interceptors large enough to handle industrial as well as sanitary wastes.
While Gray was well ahead of the field in 1884, Providence did not get its treatment plant into operation until 1900. The city of Woonsocket had a treatment plant functioning on the Blackstone three years earlier. It is interesting that officials there had the foresight to design a system with separate storm and waste lines.
The town of Warren developed a sewage disposal system in 1917, but it was not until 1928 and 1929 that East Providence and East Greenwich, respectively, took similar action. During the twenties some cases of shellfish poisoning in other states triggered demands for treatment throughout the Bay region. Worries in those days were about typhoid fever. Today meningitis is of more concern.
After World War II, when Senator John 0. Pastore was governor of Rhode Island, a new thrust for clean water began, one that shows no signs of abating today. Under continuous pressure by newspapers and the first well-organized citizens group, the Rhode Island Pollution Information Committee, which was directed by an energetic former businessman, Harvey Flint, Bay communities began to spend money in earnest for sewage treatment.
Millions of dollars were poured into plants throughout the region, and in the heavily industrialized Blackstone Valley, traditional rights of home rule were abrogated for the common good. The voters of the state established the Blackstone Valley Sewer District Commission, a powerful body that thrust aside local objections and installed dozens of miles of interceptor lines, in time bringing the collected sewage from most of the Blackstone Valley towns and cities to a central treatment plant at Bucklin's Point, East Providence. Blackstone Valley politicians carped and complained to little avail; their constituents were billed for the services provided by the regional authority, and in time learned to pay their bills as a matter of routine.
While treatment techniques originally consisted of sand filtration or irrigation and then chemical precipitation, a new biological process was developed in England in 1925, and in 1933 Providence changed its treatment to employ the English "activated sludge" technique. In this, aerobic organisms are grown in the sludge and quickly break down the raw solids and organic matter.
This system is in use throughout the Bay region today, but there are limitations, the most serious being the persistent problem of storm runoff. It is not possible to keep colonies of the "good" bacteria ready and waiting to attack unusual volumes of sewage. They can multiply only as long as sufficient quantities of sewage are available to provide food for the organisms. As long as fairly consistent amounts and kinds of wastes can be counted on, the bacteria can do their work. Also, new and exotic manufacturing wastes can throw the system out of balance. What this means to the state sanitary engineers is that the sewage treatment plants of the future must become more versatile, relying on biological processes for part of their treatment and linking back into the system some form of chemical treatment.
The goal of pristine water in the Bay and all of its tributaries is probably a mirage, enticing but unattainable. The tributaries above the sewage treatment plants already are returning to conditions of considerable purity. The Bay in general should become as clean as it has been for several decades with the Providence sewage disposal plant operating efficiently, but the areas around the big treatment plants are going to stay polluted and become more polluted. This is because present engineering practices pull sewage in from many points by webs of sewer lines to more efficient centralized treatment stations. Although the effluents from these plants can become 90 percent pure, the concentrated discharges through sheer volume are significant pollution factors in the waters close to the plants.
Today, because the pace of research has picked up in the laboratories, new water quality doubts emerge almost on a weekly basis. The worries center on heavy metals, often little more than traces, which can now be analyzed by more precise instruments available to the scientists, and on hydrocarbons, which enter the Bay's fringes in greater volumes from the sewage treatment plants than they do from tanker oil spills. One active research program is designed to investigate the possibility that hydrocarbons cause cancer in shellfish. It has been well established in recent years that some underwater creatures can take up and store chemical substances in their tissues in concentrated amounts. This finding had much to do with the ban on the use of DDT.
Although the effects on humans who consume fish and shellfish which live in waters where these chemicals and metals are found are not yet known, there has been a steady tightening of pollution control standards throughout the country. The precautionary closing of the upper Bay to shellfishing after a rainfall is an example. Another is the arbitrary downgrading of water quality classification in the vicinity of any sewage disposal plant no matter how efficient.. Also, shellfishing is banned in the summer months near the marinas and coves where boats gather.
Overall, the sewage treatment systems around the Bay are ahead of the systems used in other parts of the country. Prior to the Providence sewage disposal plant breakdown, an encouraging picture of water quality existed. Sanitary engineers have a letter system to identify quality and usage categories: A for clean water suitable for all uses, B for good bathing water with high fish and wildlife values but where harvested shellfish must be purified flushing before marketing, C for water of good aesthetic characteristics but unsuitable for shellfishing, and D and E for waters where pollutants bar ail but commercial shipping. Only the lower reaches of the Pawtuxet River, loaded with the effluents of three municipal treatment plants and a large chemical plant, were in the D category. The Providence River had improved to C status, and only a few other C areas remained, these generally in small congested coves or immediately adjacent to sewage plant outfalls.
All three entrances to the Bay, the entire central portion, and the upper Bay to Conimicut Point were in A condition. The upper Bay dropped to B following heavy rains for reasons discussed earlier. In 1977, the entire Bay was considered 92 percent clean. A goal of 96 percent had been set for 1983, a level of purity few great estuaries in the industrial nations of the world can equal. The troubles in Providence have upset that timetable, but the goal will still be pursued.
Next Chapter: Resource Management |
Table of Contents