1 / 19

VICTORIA’S SEWAGE The story you haven’t heard

VICTORIA’S SEWAGE The story you haven’t heard.

marshm
Télécharger la présentation

VICTORIA’S SEWAGE The story you haven’t heard

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. VICTORIA’S SEWAGE The story you haven’t heard For years the Capital Regional District has vigorously campaigned against the upgrading its two largest sewage treatment plants at Clover Point and Macaulay Point on the basis that the current method of discharging raw sewage to the marine environment is a benign, environmentally safe practice. Today you will hear otherwise.

  2. Introduction • I am John Werring. I am one of Sierra Legal’s staff scientists. I have been with Sierra Legal for more than 14 years. • Today I will present to you with a brief synopsis of what we know about the state of the science and what it says about environmental impacts related to Victoria’s sewage.

  3. Topics of Discussion • What the CRD’s environmental studies, new independent studies, and the passing of time can tell us. • Why should we be concerned? • What do we want the CRD to do?

  4. Environmental studies and the passage of time • CRD has been monitoring the Clover Point and Macaulay Point outfall zones since 1970, before the outfalls began flowing. • In 1970, prior to discharge, the sea bottom around the Macaulay outfall consisted primarily of sandy substrate. Around Clover outfall it was rocky. • Animals present included swimming scallops, clams, prawns, snails and mussels, bottom fish like sole and cod, and a variety of sea worms and hermit crabs.

  5. Environmental studies and the passage of time • By 1972, just two years after the discharges began, molluscs, hermit crabs and sea worms were showing up in fewer numbers in the area around the end of the Macaulay pipe. • In their place, worms. Worms that had not been there previously. One species, Capitella capitata, is commonly associated with pollution caused by sewage effluents. Their presence is an indicator of high organic loading, and a low-oxygen, seabed habitat.

  6. Environmental studies and the passage of time • By 1976, the seabed community closest to the outfall was completely dominated by these worms. Molluscs and other bottom living organism were only found in very low numbers. Hermit crabs were not found at all. • By early 1988, many of the species that were common around the outfall in 1976 had disappeared completely. The benthic community had become totally dominated by the worm Capitella capitata.

  7. Environmental studies and the passage of time • By 1991 new studies showed that high numbers of worms were beginning to appear at distances up to 100 m away from the Macaulay Point outfall. • Mussels, clams, and crabs at these locations began declining in number as well.

  8. Environmental studies and the passage of time • Undersea photography showed the seabed as far as 500 metres from the Macaulay outfall was covered in decomposing sewage. • Researchers noted that “excess organic matter, from the outfall, is accumulating and decomposing as would be expected…if the organic load continues to increase then larger benthic invertebrates (e.g. sea anemones) will be lost and replaced with smaller organisms (e.g. worms)”.

  9. In 1998, Crone et. al, conducted a drift card study that showed that 60% of floatable solids from CRD outfalls remain in Victoria Bight. It stands to reason that suspended solids do also and settle out in the area. More recently, Markovic’s thesis shows that the range of impacts from the CRD’s sewage extends over a much larger area. The ocean bottom over virtually the entire Victoria Bight shows evidence of sewage pollution. Environmental studies and the passage of time

  10. 40 Square kilometres of ocean off Victoria is closed to shellfish harvesting because of concerns about sewage contamination More often than not, surface fecal coliforms counts in the waters off Victoria exceed safe limits for human recreational use. Environmental studies and the passage of time

  11. Environmental studies and the passage of time • All of this tells us that the sea bed in the vicinity of the outfalls was becoming polluted with sewage from the outfalls and that the pollution field has expanded widely over time. • Crone’s 1998 study and Markovic’s recent findings also tell us that the water column throughout the entire Victoria Bight may also be contaminated by sewage effluent.

  12. Why should we be concerned? • Toxicity studies on the effluent from both outfalls reveal that the effluent kills all test organisms exposed to it within minutes of exposure. • The liquid effluent contains very high levels of heavy metals (including mercury) and persistent organic chemicals like PAH’s, phthalate esters, pesticides, herbicides. It also contains PCB’s

  13. Why should we be concerned? • The CRD does not monitor the water column so we have no idea just how polluted the sea off Victoria is, despite the fact that we now know that much of the sewage stays in the area…it is not flushed away. • Independent tests confirm this yet the CRD continues to maintain the problem is minimal and highly localized (within a few hundred metres of the outfalls).

  14. Critical Scientific Flaw Underestimates Extent of Pollution • Science is about controlled experiments; • To determine if an area is impacted by an event, you need a comparison site that is remote from the study area and deemed free of impacts…or pristine.

  15. Critical Scientific Flaw Underestimates Extent of Pollution • The control site for comparing benthic samples collected at Clover and Macaulay was Parry Bay, 12 km to the southwest of the outfalls. • In 1992, SeaConsult, a Victoria consulting firm determined that Parry Bay was a likely settling point for sewage solids from Clover and Macaulay. Markovics thesis confirms this.

  16. Critical Scientific Flaw Underestimates Extent of Pollution • What this means is that the true environmental impact of the discharges at Clover and Macaulay ass determined by the CRD’s studies has been greatly under-estimated. Yet the CRD continues to rely on these flawed studies to assert their case. If anything the more recent science tells us that these impacts may extend up to 12 km away from the outfalls and to an extent that has yet to be determined.

  17. SUMMARY • The scientific evidence shows that the discharge of raw sewage from Clover and Macaulay IS having an impact on the environment; and, • We don’t really know just how great that impact is but we do know it is getting worse over time.

  18. What we want the CRD to do • We want the CRD to move towards upgrading the Clover and Macaulay sewage treatment plants to a minimum of secondary sewage treatment immediately • NOT 30 years from now

  19. How Can YOU help? • Help spread the news that the Status Quo is not acceptable. • Write your MLA, your MP and the CRD and demand action.

More Related