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CK Ventures Ltd.
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The Big Pipe, the Big Problem, the Solution |
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Author: |
Curt Kerns, M.Sc., R.P.Bio.,
C.F.S. |
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Affiliation: |
CK Ventures Ltd. |
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Date of Presentation: |
May 18, 2000
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Definitions: |
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Wetlands: |
Those
lands which at least seasonally water is at or above soil level. |
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Wastewaters |
Those
waters to which substances have been added |
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Watersheds |
Those
areas in which water respects gravity, not political subdivisions. |
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Waste Treatment: |
The returning of the constituent components
of waste compounds to carbon dioxide, water, and minerals. |
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Introduction: |
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North
America once had vast areas of wetlands associated with virtually all
major and many minor river systems. Over their extensive range, beavers
made wetland ponds to further filter and treat runoff.
Draining and diking by agriculturists caused wetlands to be
turned into croplands and essentially mined for their nutrients.
As town grew into cities, wetlands are routinely filled for
space. Many a highway has
been built through marshes as its cheaper.
Since
Europeans landed, over half of the wetlands of North America have been
lost. California has lost 99% of its former wetlands. As development proceeded in North America, now lacking the
functions of wetlands, riverine and ocean discharge of wastewaters was
deemed to be the solution. The
effect upon coastal waters has been devastating.
Ecological changes are occurring at an increasing rate.
Coastal waters do not process excessive nutrients well unless
they are in an elemental form such as occurs with upwelling. Urea
has been found to differentially favor dinoflagellates over that of
diatoms. The sheer quantity
of nutrients coming from land has become a problem.
When nitrogen to phosphorus to silica ratios become skewed,
species and taxa of phytoplankton utilized by economically beneficial
species of fish and shellfish flourish.
Immense disruptions occur. It
grows worse with the addition of the wastes from each animal, from each
human, from each suburban lawn, or fertilized cropland is added.
And it’s the world over, not just North America.
The Problem:
The essential problem with
wetlands has been that the benefits are diffuse and the property owners
have hitherto only been able to extract value by destruction of wetland
functions. Ocean and riverine discharge of untreated or even partially treated
wastewaters are causing ecological disruptions of an unprecedented
scale. Discharge into
coastal waters of the 25 billion plus liters of sewage per day from
North America is wreaking havoc with the waters of the continental
shelf. Bioaccumulation of
human-made toxicants is resulting in wastes returning to land to haunt
us. One of the ways returning wastes are in evidence is in
wildlife. Adult sockeye
salmon Oncorhynchus nerka returning to pristine wilderness
areas of Alaska have been demonstrated to be the source of industrial
compounds discharged and blown from lands.
Their carcasses have been found to be the source of contaminants
now found in grayling. Sockeye
feed lowest on the food web of all species of Pacific salmon so should
be expected to be the least contaminated.
The “good news” is that most of the world’s other oceans
are far more polluted than the sub Arctic Pacific. As British Columbia
salmon commingle on the same feeding grounds as do Alaska salmon, we can
expect the same contamination to be occurring here.
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Killer
whales from further north who feed largely on marine mammals show even
higher levels of pollutants. Indications
are that B.C. orca are some of the most chemically contaminated marine
mammals in the world2. PCBs
(poly-chlorinated-biphenyls) and other substances originating from land
both as aerosols and in wastewaters are implicated.
Levels of PCBs detected in B.C. orca are in excess of those found
in beluga whales in the St. Lawrence River1.
Hormone interfering substances found in pesticides, herbicides,
plasticizers, and detergents also originating from land are also
implicated. A hundred
years ago harmful algae blooms,
or red tides, were typically found only in northern waters such as off
the coast of New England and the Maritimes on the East Coast and in B.C.
and Alaska waters. By fifty
years ago, they occurred off most major cities.
Now they surround
North America. In 1998,
over 400 sea lions died from the ill effects of a harmful algae bloom in
Monterey Bay, California. Increases
in global temperatures are projected to warm and consequently dry the
east side of Vancouver Island and the Lower Mainland inordinately.
Summer flows of salmonid streams will further decrease.
Wastewater treated and detoxified could be the source of water
for stream flow augmentation.
The
Solution: The solution to pollution is NOT
dilution; it is land-based treatment utilizing plants.
On-land, plant-based tertiary treatment of all wastewaters,
essentially mimicking how nature functions, is the solution.
Now, with the widespread use of constructed wetlands beginning,
direct economic value can be derived from wetland functions.
Ratepayers who would see their taxes go up to build new or expand
existing wastewater treatment facilities can save millions of dollars by
paying for the leasing of wetlands for wastewater treatment. We must restore
wetland functions to wastewater treatment.
Communities across the world are using Constructed Wetlands for
domestic wastewater treatment. Naturally occurring wetlands for water
and wastewater treatment have long been used to treat wastewater.
London, England has used wetlands to treat its wastewater for
over a century. Now cities
such as Sacramento, California, and Phoenix, Arizona have built
pilot-scale wetlands and are in the process of scaling up their
operations to full-scale treatment.
Wetlands
have a myriad of functions: Remove
and detoxifying substances carried by and dissolved in water Nutrient
sinks Constructed Wetlands (CW) are probably the
most flexible water treatment and retention mechanism yet discovered.
Aquatic and terrestrial plants are useful for treating municipal
effluents from major cities, industrial wastewater, agricultural runoff,
storm water runoff, animal wastes, acid mine drainage, landfill leachate,
domestic wastewater from subdivisions, office complexes, shopping
centers, and individual businesses and homes.
Plants can be used to detoxify, remove nutrients, heavy metals,
and all but eliminate pathogens from wastewater streams of most all
types. Constructed Wetlands are a relatively new (to North America)
water pollution control technology.
Constructed Wetlands are the treatment of waste compounds from
contaminated water using aquatic plants, microorganisms, and
physiochemical processes that occur in shallow ponds. Questions
and Answers about Constructed Wetlands In the Pacific Northwest,
Arcata, California has used a Constructed Wetland to excellent advantage
since 1986. Diagram
& Performance of Arcata, Calif. Constructed Wetland Constructed Wetlands for single-family
dwellings are the wave of the future.
They offer unparalleled treatment effectiveness, achieving true
tertiary treatment, reliability that is way beyond that which we are
accustomed to, plus can actually cost less than other treatment
methodologies that are not nearly as effective.
In the U.S. over 500 homes with primary treatment alone followed
by what essentially amounts to an aquatic plant-filled lineal ditch with
very high quality water coming out the other end demonstrate well the
feasibility. Unfortunately
it not that simple! To
insure public health concerns are met further treatment followed by
disinfection is required. In
areas that would otherwise require a mound system, as the ground will
not perk, high rate aeration secondary treatment followed by UV
disinfection and then a Constructed Wetland is the future.
Wetlands can provide superior performance, better protect public
health, ground- and receiving waters, and can also cost less.
To meet B.C. Ministry of Health regulations any overflow should
be directed to a gravel-filled trench, depending upon specific site
constraints, preferably as narrow and deep as the equipment will allow.
Constructed
Wetlands for Single-Family Dwellings Salcor
Engineering Ultra Violet Treatment Examples
of Constructed Wetlands for Single-Family Dwellings
Forestlands
can effectively receive considerable quantities of wastewater while
maintaining very effectively treatment.
Over 25 meters/yr. have been applied to what was a dry oak
forest. Intensive
investigations revealed excellent water treatment efficiencies. 3,000
gpm of beet processing wastewater Forest
receiving 26 m per year of wastewater
Overland
flow, that is spreading wastewater through grasses in broad, shallow
swales or fields, has been demonstrated for over 30 years to also be a
very effective tertiary treatment procedure. The
criteria are well established. Agriculture is an important source
of point and non-point nutrients. British
Columbia already has a number of Constructed Wetlands that have
demonstrated excellent treatment capabilities.
Constructed Wetlands work well in areas that form ice cover in
the winter. Constructed
Wetland in Prince George Land area
estimated to effectively treat and manage wastewater comprises only
about 1 - 3% of the average
watershed. Here is what the
widening of drainage ditches did for the peak flows for one community. http://www2.ncsu.edu/eos/service/bae/grad/klbass/www/instream.html |
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Conclusions: |
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North
America has lost most of its original wetlands, consequently the
functions of wetlands to filter, precipitate, and detoxify wastes from
water. “Big Pipe”
solutions are not solutions at all, merely deferring the problem
resulting in pollution of the world’s oceans.
We in Cascadia are seeing it in the contamination of our salmon
as well as the rapid loss of orca.
As low levels of contamination bioaccumulate, toxicity increases
further up the food chain. Humans
are at the top of the food chain. Planning
must be done on a watershed basis for water and wastewater.
Areas that can be readily attached to "the big pipe"
have been. Decentralization
on a watershed basis using primary or secondary treatment followed some
sort of by land-based, vegetative treatment is the way to proceed.
Land-based treatment methodologies such as constructed wetlands,
forest application, low and high rate overland flow, and drip irrigation
all have their uses. Ancillary benefit can often result or can be designed in:
stormwater runoff desynchronization, winter retention for summer
releases to augment stream flows, aquifer recharge, wildlife habitat
restoration, and human recreation and education |
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1Lunman,
K. (1999). B.C. killer
whales threatened by PCBs’, Canadian marine researchers conclude.
The Globe & Mail, Oct. 13, p. 2. 2Tafler,
S. (1999). The killer
whales off B.C.’s coast are dying.
The Globe & Mail, Oct. 15, p. 15.
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