- SEA LIFE 'DEGRADED' AT SEWAGE OUTFALL
- SHORE LIFE AROUND VICTORIA SHRINKING, STUDY SAYS
- GUERNSEY UPDATES (2)
- OCEANS HAVE ACIDIFIED MORE IN THE LAST 200 YEARS THAN THEY DID IN THE PREVIOUS 21000 YEARS
SEA LIFE 'DEGRADED' AT SEWAGE OUTFALL
January 25, 2012
The shrimp, mollusk and sea worm population near the Macaulay Point sewage outfall station has been "highly degraded," although the precise cause isn't known, according to a report to be given to the region's environment committee today.
Macaulay Point is one of the sites where screened liquid waste is dispersed into the ocean. A similar situation was not found at the other key site, Clover Point.
The findings are part of an annual report by the Capital Regional District to monitor and assess the impact of sewage discharge on the ocean and on public health.
The region has long discharged its sewage into the ocean via the outfalls, where sewage that is left after going through six-millimetre screens is carried via a pipe. At Macaulay Point, the sewage is put into the ocean 1.7 kilometres from shore through 28 diffusers at the end of the pipe. That allows the liquid waste to be discharged through all of the "ports" so it is spread more efficiently through the water, the report says. At Clover Point, the pipe extends 1.1 kilometres into the ocean and the sewage is dispersed through 37 ports.
Supporters of the system say the region has a unique marine environment that allows sewage to diffuse without causing problems.
But others say it is a black eye for the region and has drawn worldwide attention for damaging the environment.
The province has mandated the CRD to have a secondary sewage treatment system in place by 2016. The date is likely to be pushed into the future because the region is still waiting for the provincial and federal governments to confirm their parts of three-way funding for the $782-million project.
Although tidal currents take away most of the wastewater, about one per cent settles on the ocean floor. It is this material that could be causing a problem for sea life near Macaulay Point.
The benthic invertebrate communities - animals that live in the sediment - have significantly declined in health since 2008, the report says. The most significant outfall effects are within about 200 metres east of the end of the Macaulay Point pipe. However, the report noted that "more detailed assessments indicate that truly negative effects have become more pronounced since 2008."
The degradation has expanded to areas 400 metres east and southeast of the outfall, near spots that previously showed neutral effects. They are now experiencing slightly negative effects, the report says.
"At this point in time, it is not possible to confirm the cause of the observed declined in the benthic community health," the report says. "Macaulay Point wastewater and sediment quality have both been improving or have remained relatively constant over the same time period and one would, therefore, expect improvements in benthic community health over the same time period."
CRD staff are consulting experts to determine whether the decline is a result of an unmeasured outfall impact, or whether it indicates a broader environmental shift, such as climate change in the Strait of Georgia and Juan de Fuca Strait.
The environment committee is due to discuss the report today.
ARESST: The CRD's report on Macaulay outfall (not Clover Point) suggests that in 2010 (not previously) there may be a problem found with shrinking communities of shellfish. However, the report also comments that:
Preliminary information indicates that similar declines in benthic community health have been observed over the same time period at other monitoring stations in the Strait of Georgia, Juan de Fuca Strait and Puget Sound, even at locations far away from point sources of pollution such as municipal wastewater outfalls (page 2).
Below is an article previously included in ARESST News that explains more about the issue of shrinking communities around the Salish Sea region.
SHORE LIFE AROUND VICTORIA SHRINKING, STUDY SAYS
Victoria Times Colonist
November 30, 2011
Intertidal habitats in the Strait of Juan de Fuca that were once teeming with mussels, barnacles and hundreds of other species have shrunk by as much as 51 per cent due to rising water temperatures, according to a study by University of B.C. zoologist Chris Harley.
As recently as 50 years ago, mussels and barnacles thrived in thick bands across beaches on Vancouver Island, the Olympic Peninsula and the San Juan Islands, providing habitat for up to 300 other species of sea creatures.
Beaches on the relatively cool west coast of Vancouver Island are much as they were five decades ago, but those in the warmer waters further up the strait are in steep decline, according to the article published this week in the journal Science.
The shrunken mussel beds are now home to as few as 10 other species, he said.
As the mussels and barnacles are forced down the beach into cooler waters to stay within a suitable temperature range for their survival, they are being devoured by sea stars that feed at the bottom edge of the intertidal zone.
"Sea stars are the terrors of the intertidal zone," said Harley.
"As it gets hotter you would expect [species] to just move down to lower positions on the shore where they wouldn't be out of the water for so long. But things aren't shifting in unison."
The sea stars are camped out where they have always been, consuming the other species as they are forced by rising temperatures down the beach, out of their predator-free zone.
Harley came across detailed data on intertidal zones in the region collected for a 1959 masters thesis by UBC marine biologist Tom Widdowson, who measured the upper and lower limits of a variety of species at sites throughout the strait. Widdowson supplied Harley with the Google Earth co-ordinates of the exact locations he had studied in 1957 and 1958.
New measurements at those locations were revealing.
"The outer coast, being cool, still supports amazing biodiversity with really wide mussel beds and all kinds of species in them," said Harley.
"But as you come in toward Port Angeles and Sooke [the beds] get narrower and you just find a few [individual mussels] around Victoria and they are gone completely by the time you get to Friday Harbour."
Daily high summer temperatures in the area have increased by 3.5 C degrees over the past 60 years.
Harley erected cages in a few locations to exclude the sea stars and found that the mussel beds and some of the species that thrive in those beds recovered within a year.
"Global warming is already having significant ecological impacts and it's only going to get more dramatic," Harley predicted.
Mussels provide habitat for hundreds of other species that may face extinction when the habitat mussels provide shrinks or vanishes, he said: "A mussel bed is like an apartment complex - for crabs, and other small crustaceans, snails, worms and seaweed."
victoriatimescolonist/news/ story.html?id=d7e13bfa-eb2c- 4ac7-8b78-eef9517c647d
GUERNSEY UPDATES (2)
Guernsey: Sewage warning for ferry passengers sailing here
This Is Guernsey Press
23 January 2012
TOURISTS boarding ferries in Weymouth and Portsmouth today will be warned that Guernsey pumps 16,000 tonnes of raw sewage into the sea each day.
Surfers Against Sewage said hundreds would never come back to the island after it waged war on Public Services’ proposals not to have full sewage treatment that will be debated at this week’s States meeting.
As well as posting messages on its Facebook group and urging members to hijack the networking site’s Guernsey page with messages of disgust, SAS visited the island last week with a cardboard cut-out of a surfer covered in excrement.
Asked about the impact on the island’s reputation and tourism industry, SAS campaigns officer Dom Ferris said ‘don’t shoot the messenger’.
Guernsey: De Lisle wants PSD to progress sewage work
This Is Guernsey Press
23rd January 2012
PUBLIC SERVICES will be forced to continue investigations into building a full sewage treatment plant, if an amendment from Deputy David De Lisle is successful.
The department’s report into liquid waste said that building a full sewage plant, at a cost of up to £55m., could not be justified because research had shown the current arrangements had very little impact on the environment. It recommended that the long sea outfall pipe is replaced and fitted with diffusers.
But Deputy De Lisle, pictured, said this was a short-sighted view.
‘I am not asking for a sewage plant, only to do all the preliminary work so we are ready to put one in when finances allow.’
OCEANS HAVE ACIDIFIED MORE IN THE LAST 200 YEARS THAN THEY DID IN THE PREVIOUS 21000 YEARS
23rd January 2012
Man-made carbon emissions have acidified the world's oceans far beyond their natural levels, new research suggests.
In some regions, acidity levels rose faster in the last two centuries than it did in the previous 21,000 years, a study from the University of Hawaii has shown.
Ocean acidity makes it harder for organisms such as molluscs and coral to construct the protective layers they need to survive.
Measuring changes in ocean acidity is difficult because it varies naturally between seasons, years and regions.
Scientists looked at changes in the saturation level of aragonite, a form of calcium carbonate used to measure ocean acidification.
As seawater acidity rises, the saturation level of aragonite falls.
Direct observations only date back 30 years, which is not long enough to reveal a meaningful trend.
However the new research used simulations of ocean and climate conditions going back 21,000 years to the Last Glacial Maximum and forward in time to the end of the 21st century.
In several key coral reef regions aragonite saturation is already five times below its lowest pre-industrial range, according to the model.
This translates to a decrease in overall calcification rates of corals and other shell-forming organisms of 15%, scientists at the university believe.
They fear calcification rates of some marine organisms could drop by more than 40% of their pre-industrial levels within the next 90 years.
Dr Tobias Friedrich, from the University of Hawaii, who led the study published in the journal Nature Climate Change, said: 'Any significant drop below the minimum level of aragonite to which the organisms have been exposed to for thousands of years and have successfully adapted will very likely stress them and their associated ecosystems.
'In some regions, the man-made rate of change in ocean acidity since the industrial revolution is 100 times greater than the natural rate of change between the Last Glacial Maximum and pre-industrial times.'
He added: 'When Earth started to warm 17,000 years ago, terminating the last glacial period, atmospheric CO2 (carbon dioxide) levels rose from 190 parts per million (ppm) to 280 ppm over 6,000 years.
'Marine ecosystems had ample time to adjust. Now, for a similar rise in CO2 concentration to the present level of 392 ppm, the adjustment time is reduced to only 100 - 200 years.'
Co-author Professor Axel Timmermann, also from the University of Hawaii, said: 'Our results suggest that severe reductions are likely to occur in coral reef diversity, structural complexity and resilience by the middle of this century.'
sciencetech/article-2090253/ Oceans-acidified-200-years- did-previous-21-000-years- claims-new-climate-change- research.html