Falling coliform counts on Vancouver beaches

Falling coliform counts on Vancouver beaches

Volume 17/Number 11/November1986 and dredge-and-fill activities. However, the Bay is subject to numerous contaminant inputs, which include runoff from...

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Volume 17/Number 11/November1986 and dredge-and-fill activities. However, the Bay is subject to numerous contaminant inputs, which include runoff from agricultural land; urban and industrial discharges and runoff; dredged material; storm runoff; and mine tailings dumped in the Bay in previous years. The State of California and EPA are working to define the problem and establish methods to properly manage the Bay. One of the activities affecting the Bay will receive judicial review in November. The Corps of Engineers has filed suit against a large landowner in the San Francisco Bay area over development of lands which the Corps claims to be isolated wetlands and which the development company claims are not wetlands under Corps jurisdiction. The company claims the lands are usually dry and are not near any navigable waters, while opponents claim the areas are merely lands made available by diking the Bay. The suit is expected to result in a clarification of the definition of dredge-and-fill activities and seasonal wetlands, and to determine when a wetland is adjacent to a navigable water body. Developers sometimes perform activities that convert wetlands to drylands so that they can then be developed. Such activities include draining, ditch-digging, and disking to remove vegetation. The Corps must obtain permission to inspect private land directly, but the Corps inspects land using binoculars or helicopters if they suspect illegal activities are being conducted. If the Corps determines that the landowner is performing illegal activities, it can issue cease-and-desist orders.

Red Tide Outbreak Affects B.C. Shellfish Fisheries and Oceans Canada closed all molluscan shellfish harvesting waters in British Columbia, except three small areas, on 11 July 1986, owing to a red-tide alert. The whole coast of British Columbia was closed for molluscan shellfish harvesting on 16 July. Mussels, clams, scallops, and oysters were affected. On 9 August, the ban was lifted for oysters, scallops, manila clams and littleneck clams for much of the southern British Columbia coast. The closure, however, remained in effect after that date for butter clams and mussels in these areas. Also, any areas that had been closed owing to high faecal coliform counts remained closed. This has been the worst outbreak of red tide on the British Columbia coast in several years, and the first time in 6 years that Fisheries and Oceans banned commercial and recreational harvesting of bivalve shellfish along the entire British Columbia coast owing to red tide. It is attributed to an ideal combination of water stratification due to heavier-than-usual early-summer precipitation and runoff, nutrients, temperature and sunshine for intensive blooms of the causative phytoplankton organism. The toxic organism responsible for the present red tide has been identified as the dinoflagellate Protogonyaulax catenella. It causes paralytic shellfish poisoning in consumers of shellfish that have accumulated the toxin from it. The worst outbreak of paralytic shellfish poisoning on the coast of British Columbia occurred in the late summer of 1957. Even the Pacific oyster Crassostrea g/gas was affected at that time. The most recent shellfish

closure affecting the whole British Columbia coast, prior to 1986, occurred in 1980. A 33 year old man died after eating butter clams, Saxidomus giganteus, harvested from a closed area in Health Bay on Gilford Island, off the northeast coast of Vancouver Island. Those clams contained 8,600 ~tg 100 g-i of toxin in the meat. Anything over 80 ~g is considered unsafe for human consumption. In the current outbreak, a test on mussels, Mytilus edulis, harvested in Okeover Inlet, north of Powel River, on the east side of the Strait of Georgia, gave a reading of 14,000 p.g 100 g-1 of meat. Recent tests, just prior 9 August, gave toxin levels of 560 and 1,400 ~tg 100 g-I in butter clams and mussels, respectively, from Okeover Inlet. Perhaps the hardest hit by the shellfish harvesting ban has been the commercial clam industry of British Columbia, which annually harvest 1.3-1.8 million kg of clams, 80% of which is exported to the USA. Butter clams can take as long as two years to cleanse themselves of the paralytic shellfish toxin. Scientists say that the 1986 outbreak of red tide to Protogonyaulax catenella might have been predicted, because it appears to have a six-year cycle, and the last major outbreak occurred in 1980.

MICHAEL WALDICHUCK

Falling Coliform Counts on Vancouver Beaches Vancouver beaches suffered some of the highest faecal coliform counts in many years during the summer of 1986 (see Mar. Pollut. Bull. 17, 393). Federal guidelines state that a faecal coliform count of 200 MPN (most probable number) per 100 ml of water is unacceptable for bathing. Numerous beaches were posted as being polluted because they exceeded this limit. Counts made on samples taken on 5 August, after a period of dry, warm weather, showed that counts on most of the beaches in outer Burrard Inlet fell below 200. Wreck Beach on the University of British Columbia Endowment Lands, the beach closest to the mouth of the Fraser River and the outfall of the Iona Island Sewage Treatment Plant, however, was the exception and continued to give faecal coliform counts ranging between 200 and 250. Warnings were posted at Wreck Beach on 18 July and remained in effect after 5 August. Public health authorities warn bathers that they risk health problems such as diarrhoea and throat and ear infections if they swim in waters with high faecal coliform counts. The city engineer of Vancouver pointed out that the high coliform count in English Bay of outer Burrard Inlet earlier in the summer was due to the unusually high spring Fraser River runoff, the highest in 14 years, and an increase in boat traffic. Polluted Fraser River water can sweep around Point Grey and into English Bay during the flooding tide. Likewise, effluent from the Iona Island Sewage Treatment Plant can be swept around a jetty on the north side of the effluent trench and onto Wreck Beach and into English Bay. It was noted also by the city engineer that the city needs pump-out facilities for pleasure craft and sewer connections for all 'live-aboard' marinas. Then regulations 485

Marine PollutionBulletin have to be enacted to prevent pleasure craft from discharging sewage into False Creek and the southeast portions of English Bay. After this legislation is in place and pleasure craft are regulated, the next step would be to address commercial and international vessels. MICHAEL WALDICHUK

New Test for Bathing Water Quality

ligak is a world-class discovery". Gulf has hoped to continue with a $140-$180 million drilling programme during the winter of 1986-87- The company, one of the few survivors in the Beaufort Sea, had helped to develop techniques in exploration and drilling for oil and gas in ice-infested waters of the Canadian Arctic with environmental safety that was unmatched by those of any other country. MICHAEL WALDICHUK

The chief medical health officer of Vancouver, Dr John Eastern Pacific Blatherwick, stated on 18 August 1986 that enterococci testing will be introduced next summer to determine the A meeting of elected legislators of the US Pacific Coast safety of Vancouver's beach waters for bathing. Like States was held in Seattle, 22-23 August 1986, to conother North American cities, Vancouver currently relies sider issues arising from ocean resources. These include on the faecal coliform count to detect unsafe levels of pollution topics such as ocean incineration, deep sewage contamination that make swimming and shell- mining exploration and production, deep ridge industrifish harvesting risky from a health point of view. The ally significant sulphur-metabolizing bacteria, offshore federal guideline for acceptable levels for bathing is a leasing of mineral rights, ocean dumping of wastes and faecal coliform count of less than 200.100 ml -J of oil spills, State's interests in the 200-mile Extended water. Some of Vancouver's beaches were closed in the Economic Zone. In attendance were representatives, summer of 1986 because faecal coliform counts senators and assemblymen from Hawaii, California, exceeded the federal guidelines. Oregon and Washington. The group is preparing a The British Columbia Medical Association passed a White Paper with recommendations on policies for the resolution in July 1986 asking the provincial Health 1987 Western Legislative Conference. Ministry to review its water-quality monitoring and to D E R E K ELLIS consider changing from the faecal coliform test to enterococci testing, because the latter scored high in recent US studies as a more accurate measure of the potential for humans to get sick from swimming in con- U.S.S.R. taminated water. The US Environmental Protection The Soviet Union has just completed a radiation conAgency has recently published its final report on trol vessel that will be stationed in the port of Murenterococci testing and has recommended the test over mansk at the western end of the North-East Passage. the faecal coliform test. Dr Baltherwick noted that The vessel provides facilities for nuclear powered ice enterococci is a very specific test that will mainly breaker crews and is fitted with special quarters and indicate the risk of gastrointestinal diseases. In the equipment to detect possible radiation, clean up, Seattle, Washington, area, enterococci testing has change, work, and rest. The accommodation comprises already commenced as a specialized project. But the two separate 'contaminated' compartments with indifaecal coliform test continues as the standard. Entero- vidual clean compartments, one for the maintenance of cocci testing would not be adopted as a new standard in the crew of the ice breaker and the other for the crew the Seattle area for at least 2.5 years. operating the vessel. Contaminated water, such as that Faecal coliform testing would have to be continued, from showering, is collected in special tanks and coneven if enterococci testing is adopted, however, to taminated clothing stored in shielded chambers. determine whether shellfish are safe for harvesting. The builders believe that as the tonnage of nuclear MICHAEL WALDICHUK powered ice-breakers increases there will be a growing demand for vessels of this type. (Source--Lloyds List).

Round-the-World News

Gulf Canada Pulls Out of Beaufort Sea Mr Dan Motyka, a vice-president of Gulf Canada Corp. in Calgary, stated on 22 August 1986 that the company expects to be completely out of the Beaufort Sea by the beginning of November. Declining world oil prices were cited as the main reason for this move. If prices increase, Gulf may be back. Gulf had a highly promising discovery in the Amauligak reservoir with a flow-rate through a delineation well approaching 16,000 bbl a day during a test. Mr S. K. McWalter said that the delineation well "recorded what is believed to be the highest actual flow rate~ of any well in Canada", a result which matched Gulf and partners' expectations. He further stated that "the current series of testa has given us great confidence in reserve volumes and reservoir producibility. Amau486

Sweden Silja, the largest ferry line in Sweden and whose company symbol is the seal has agreed to sponsor research on grey seals in the Baltic. Baltic grey seals now number less than 1500 and are threatened by pesticides, erosion of their island homes and the drowning of pups in ships' wakes. Silja have committed around SFr 500 000 to projects that identify grey seal breeding sites and territories, recommend how to reduce pesticide problems and to identify new protected areas. Sweden's Kign Carl Gustaf XVI, President of the World Wildlife Fund, hosted a launch press conference to announce Silja's commitment which is seen as a glowing example of how nature and business can benefit through a World Wildlife Fund tie up. (Source-- WWF News).