|
FORENESS ENVIRONMENTAL ACTION Secretariat: 34 Clarence Avenue, Margate CT9 3DR |
NEWSLETTER NOVEMBER 2002
Bathing Waters Quality.
You may have read the Gazette (18th Oct.) report that the bathing water quality in Thanet is improving. This news is an over-simplification of the known facts. Quality is assessed by 20 bacteriological tests carried out at weekly intervals throughout a summer. Two test failures results in loss of any Blue Flag award for the following year.
Analysis of the faecal coliform (sewage indicator bacterium) test data for the past twelve years shows that Margate bay is safest for bathing early in the summer (May to July) since the level of coliforms markedly increase for the August-September period Curiously, this was not the case, however, when the beach failed the mandatory test levels for 2001 and for 1991 when June and July respectively became the guilty months. Had spills from Tivoli brooks been regularly responsible many more annual failures would have taken place.
The foulest beach in Thanet had been at Ramsgate, it failed the quality assessment standard every year from at least 1988 thru' to 1995. Improvement upcoming with the new sewage works at Weatherlees. A similar incident occurred for Herne Bay.
Broadstairs beach failed the assessments for 1991, 1996 and 1998: so no wonder Southern Water Services Ltd wants to transfer some crude sewage to the proposed Longnose Spit (Foreness ) works extension. Incredibly, in 1998 the number of test failures at Broadstairs was 10. This in contrast to fue 3 such failures for Margate in 2001. Clearly, the existing sewage works for Broadstairs (North Foreland) cannot cope. Joss Bay failed assessment in 1998. Tests at Westgate, Westbrook and Walpole bays only appear from 1998 onwards. Fulsham Rock, St.Mildred's and Minnis bays had the least contamination, apart from much beached sanitary detritus (no changes).
On any test day non-uniformity in the levels of coliforms found among our beaches reflects the complexity of surface water sewage disposal brought about by interaction of estuarine and coastal flows, marine tides and weather. A substantial proportion of coliform bacteria in sewage spills retain their viability beyond 10-days of exposure.
The foregoing tests were carried out applying the mandatory standard fixed by the Bathing Water Directive 1975. The reformed Bathing Water Directive 2002 (now overdue) will introduce a more stringent new test level for coliforms based on beach safety studies as compiled by the WHO. The number of weekly test failures per holiday season for all Thanet beaches, therefore, will increase. For example, Margate bay would have failed 8 weekly tests in 2001, and failed 14 tests in 2000. Test failure also would be likely whenever crude sewage is mixed with rainfall run-off. Ramsgate would also regularly fail despite its new sewage works at Weatherlees!
Hence the new sewage works necessary for the Margate/Broadstairs catchments should include stormwater-sewage holding tanks (for UV-disinfection of the crude sewage before later discharge) and a chemical stripping unit.
POPULAR FEA QUIZ NIGHTS are held on the third Friday (7.30pm) of every month at the Cliftonville Bowls Centre. Newcomers are most welcome. Please phone June (223429) or Derek (869142) for your early bookings.
Association of Sewage Discharges with Margate Beach's Safety Test Failures. Brian Yeoman M.Sc & Joseph M. Gaugas Ph.D.
Governmental consultants (Cascade) suggest that between 1.3 and 2.2 million cases of stomach upsets occur in the UK every year due to bathing in contaminated bathing waters. The cause of the upsets, as well as sometimes crippling or fatal cases of sewage borne infections (bacterial and viral), are the discharges of crude sewage from CSOs (combined stormwater and sewage outfalls). In addition, sea spray aerosol can be the cause ofvirus infection outbreaks inshore. The short CSO pipelines spill onto either the beaches or foreshore at the vast majority of our 471 designated bathing beaches. The WHO asserts a high health risk at beaches impacted by crude sewage discharges.
For example, the Thanet beaches (Margate) are served by 5 CSOs and one LSO (Long Sea Outfall pipeline ). They are also responsible for a large slick of indicator coliform bacilli floating off the Thanet coast. The foremost CSO is a twin pipeline at Longnose Spit which is 'allowed' by the Environment Agency to discharge 3 times to the foreshore throughout the summer (whilst more can occur dependent on rainfall, the number is unrestricted in winter).
The situation at Margate main sands is complicated by an outflow from Tivoli Brook which carries indicator coliforms onto only a confined area of the beach adjacent to a paddling pool. Despite much effort the local council cannot find who holds responsibility for the Brook. The sands have failed the EC Bathing Water standard for sewage indicator contamination tests. Margate is located just within the shallow Greater Thames Estuary.
The government plan is to reduce CSO discharges to one spill (emergency) each year within 25-years. Human Rights require regulatory authorities to guarantee the protection of bathers' good health. Greater efforts are needed in order to much reduce this danger period. The planned extension to the Margate sewage works does not include control of CSOs. Control is obtained by installation of stormwater holding tanks so that influx can be sterilized (e.g. by UV-irradiation) during dry weather periods and prior to CSO discharge. Discharge from LSO is managed by installation of sterilization schemes (mandatory by year-2005).
Reform of the EC Bathing Water Directive 1976 is overdue and though it will require more stringent indicator microbe levels for tests at beaches, it will likely not tackle the issue of CSOs directly.
FORENESS ENVIRONMENTAL ACTION, Secretariat c/o 34 Clarence Avenue. Margate CT9 3DR