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Water Quality Tackling Non-Point Source Water Pollution in British Columbia: An Action Plan March 1999 Canadian Cataloguing in Publication Data
Although British Columbia's water quality is generally good, people are increasingly aware that the province is experiencing localized water quality pollution. Every year there are reports of public beach closures, contaminated sediments, algal blooms, aquatic weed infestations, fish kills, shellfish harvesting closures, boil-water advisories, outbreaks of waterborne illnesses, and contaminated ground water. British Columbia's efforts to protect water quality by regulating "end-of-pipe" point discharges from industrial and municipal outfalls have been generally successful, and it is now recognized that the major remaining cause of water pollution is from non-point sources, which pose significant and growing threats to our water resources. Non-point source (NPS) water pollution is subtle and gradual, caused by the release of pollutants from many different and diffuse sources, largely unregulated, and associated with urbanization, agriculture, and other forms of land development. Given the dramatic population growth predicted for BC, we must act now in a determined way to deal with this pollution, otherwise we can anticipate a continuing, gradual decline in the quality of our waters. This decline will lead to significant future economic impacts and reduced benefits from our water resources.
Major sources of NPS pollution in BC include: Land Development Agriculture Stormwater
Runoff and Combined Sewer Overflows Onsite Sewage
Systems Forestry Atmospheric
Deposition Marine Activities The quantity of pollutants originating from any one source-such as a home, business, or farm-may be very small. Nevertheless, the effects of hundreds or thousands of small sources within a watershed can add up to create water pollution. The water pollution and costs from these non-point sources are significant and can include fish kills, health concerns, degraded drinking water, diminished water-based recreation and tourism opportunities, economic losses to commercial fishing and aquaculture industries and First Nations food harvesting areas, lowered real estate values, damage to habitat of fish and other aquatic organisms, the inevitable costs of clean-up and pollution reduction, and reduced aesthetic values of lakes, streams, and coastal areas. Non-point source water pollution is difficult to manage using conventional regulatory approaches because it is hard to identify and control the many sources of pollution over a large area. The key to addressing this problem is prevention through planning and coordination, education, and source control. Wide-scale participation in the prevention of NPS pollution is necessary because the actions of so many individuals are part of the problem. The Action Plan identifies the province's role in addressing NPS pollution and the priority initiatives that should be undertaken. These initiatives have been developed following public consultation, input from several government agencies, and completion of NPS water pollution studies.
The Action Plan includes the following initiatives: A. Education
and Training B. Prevention
at the Site C. Land-Use
Planning, Coordination and Local Action D. Assessment
and Reporting E. Economic
Incentives F. Legislation
and Regulation
This broad range of actions can only succeed in protecting water quality with the support and involvement of all levels of government, First Nations, community groups, and the public. The ministry of Environment, Lands and Parks (now Water, Land and Air Protection) will lead this undertaking and has chosen a three-pronged strategy to achieve this. The implementation strategy includes:
The Ministry of Environment, Lands and Parks (Water, Land and Air Protection) is implementing the NPS Action Plan in stages, building on Actions already underway and phasing in, over five years, longer term actions that require consultation and new policy. The Action Plan should be viewed as a living document that will be subject to review and improvement over time. Further public and stakeholder comments on the Actions, which are summarized below, are welcome.
A. Education and Training — Actions
British Columbia's Commitment to Clean Water
Although British Columbia's water quality is generally good, people are increasingly aware that the province is experiencing localized water quality pollution. There are swimming closures at public beaches, algal blooms, aquatic weed infestations, fish kills, shellfish harvesting closures, swimmer's itch, serious waterborne illnesses, and contaminated ground water. While our problems are not unique and may not be nearly as bad as in many other parts of the world, they are still serious. They cost millions of dollars annually and, worst of all, lead us gradually but surely towards immense future costs and conflict, and a much reduced quality of our water resource. The good news, however, is that British Columbia is extremely lucky. Nature has granted us a vast supply of water — 25% of Canada's fresh flowing water is in British Columbia, and compared to many regions, the total water demand of our population is quite small. There is still time to turn this pollution problem around, but it must be given serious attention.
In the first public status report on the quality of British Columbia's waters, the Ministry of Environment, Lands and Parks (now Ministry of Water, Land and Air Protection) rated 124 waterbodies throughout the province on attainment of water quality objectives. About 90% had excellent, good, or fair water quality, but 10% were only borderline or poor-and non-point source (NPS) pollution was identified as the major cause. Naturally, we all want top quality water, and if we set this as a clear goal and work together, we can achieve it. This Action Plan describes the ways that the British Columbia government proposes to address NPS water pollution to achieve the goal of clean water for all British Columbians.
Changing our Approach to Water Pollution Our approach to water quality management has been to focus on controlling "end-of-pipe" industrial and municipal pollution from obvious, identifiable sources. Permits are issued that allow a specified quantity and quality of discharge from industrial and sewage outfalls to flow into receiving waters and be diluted to safe levels. Although this is one way of protecting water quality, it is only part of the solution. If we are serious about avoiding the environmental, health, and economic costs of poor water quality, we must emphasize pollution prevention rather than after-the-fact control. We know that cumulative impacts and carrying capacity of the receiving environment are critical factors. We know that we must act strategically by tackling big problems before routine ones, and by applying scarce resources to those solutions that will generate the greatest environmental benefit. And perhaps most importantly, we know that we must approach water pollution in a far more cooperative and coordinated manner. This is because NPS pollution cannot always be traced to a specific, identifiable source. NPS water pollution is subtle, gradual, and cumulative. It is caused by runoff flowing across farmers' fields, active or discontinued logging operations, on site sewage systems, home gardens, and city streets. It is caused by many small acts of pollution, and is therefore elusive and not easily regulated or enforced. We are all responsible and must all be involved in the solution; this will require cooperation and coordination at all levels, from senior governments, to community organizations, to individuals.
British Columbia, like most other jurisdictions, has focused primarily on controlling point sources of water pollution, but we are now beginning to understand the extent of NPS water pollution and the risk of not controlling it. Many costs and problems are associated with NPS pollution, including:
Non-point source pollution in aquatic ecosystems can be grouped into five main categories: Pathogens
Return
to Commitment to Clean Water
Across British Columbia, NPS water pollutants have produced a range of impacts. In the enclosed marine waters of the Capital Regional District (CRD), NPS water pollution has adversely affected recreational opportunities, degraded aesthetic values, and reduced the abundance and diversity of marine life. Victoria and Esquimalt harbours remain closed to commercial crab harvesting due to dioxin/furan contamination. Beach closures have been common throughout the CRD, primarily due to fecal matter discharged into stormwater systems. Although recent identification and elimination of sources of pathogens in storm drains that discharge near beaches has allowed beaches to reopen, several dozen storm drains remain a significant concern. In Saanich Inlet, most embayed areas are closed to shellfish harvesting due to fecal contamination from agricultural runoff, onsite sewage systems, and stormwater runoff. High levels of heavy metals have been measured in sediments near stormwater outfalls. These contaminants can cause sublethal toxicity to bottom-dwelling organisms. In areas of the Lower Fraser Valley, east from Vancouver, the most significant potential for NPS water pollution is the agriculture industry. The Abbotsford-Sumas aquifer is contaminated with nitrate leached from manure and other fertilizers applied to crops and fallow fields. Nitrate contamination is also evident in other aquifers, including Hopington and Brookswood, due to agricultural activities and onsite sewage disposal. Streams in the eastern Fraser Valley and in less urbanized areas of Langley and Surrey exhibit depressed oxygen levels caused by agricultural runoff. Low oxygen levels have contributed to coho salmon kills in the Nicomekl, Serpentine, and Little Campbell rivers near Boundary Bay in the 1980's. The same conditions exist in Matsqui Slough. In the more urbanized areas of the Lower Mainland, the negative impacts of stormwater runoff, combined sewer overflows, and occasional toxic spills have been significant. Fish kills have occurred. Nutrients and fecal contamination have reduced aesthetic values and recreational use of urban lakes. Stormwaters and combined sewer overflows contribute a significant contaminant load to Burrard Inlet, where toxic metals and organic chemicals in the sediments are potentially toxic to bottom-dwelling organisms. Advanced sewage treatment to control point-source phosphorus loading to the Okanagan Lakes over the past 25 years has led to significant improvements in water quality in most lakes. However, phosphorus inputs from non-point sources in this area remain a concern, and account for over 90% of total phosphorus loadings in the Okanagan Basin. In the Armstrong, Osoyoos, and Grand Forks areas, ground water has been contaminated with nitrates from chemical fertilizers leaching from orchards and other crops. Corrective action should reduce the problem, but unless other NPS pollution from agriculture, forestry and stormwater are also controlled, deteriorating ground water quality from increasing nitrate levels could continue. In the cattle ranching areas of the Northern and Southern Interior, water pollution from agriculture is widespread. Phosphorus loadings in runoff from cattle over-wintering areas have contributed to the eutrophication of Williams Lake in the Cariboo, with blooms of blue-green algae and critical oxygen depletion in lake bottom waters. Agricultural runoff has also affected the Thompson River and its tributaries-the Bonaparte, Nicola, and Salmon rivers. Where cattle have direct access to streams, bank erosion leads to vegetation loss, bank destabilization, and damaging sedimentation. Cattle manure can contaminate drinking water and harm fish by depleting dissolved oxygen. In coastal areas, localized discharges from boats and marinas, storm drains, onsite sewage systems, and agricultural runoff affect enclosed, poorly-flushed bays, forcing shellfish harvesting closures to prevent health risks. In other areas of British Columbia, NPS pollution tends to be localized rather than widespread, indicating the major role that land development and population growth play in NPS pollution. Land development not only increases NPS pollution directly through erosion and sedimentation from land clearing and excavation, but also increases the opportunities for NPS pollution from other sources. The cumulative effects of these point and non-point source water pollutants may exceed the carrying capacity of surface and ground waters. Understanding the connection between land use, the degree of development, and water quality is important. Determining the threshold in terms of land development versus the carrying capacity of water resources is required. In many cases, this represents a hidden danger-there may be no warning sign while nature is absorbing the load, then suddenly, as in the case of lake eutrophication, a critical threshold is reached and the waterbody's capacity to accept waste is exceeded. Once the threshold is exceeded, there are no quick-fix solutions. We have to deal with the cause of the problem, and therefore prevention is the key to NPS water pollution management.
The province has overall jurisdiction over land management on Crown lands and thus has a leadership role in managing NPS pollution. Local governments have jurisdiction over land development within their boundaries. However, a complex array of federal, provincial, and local agencies each have a role in managing NPS pollution in British Columbia. Table 1 lists relevant legislation, its purpose, and the agencies responsible. The complexity evident in the table underscores the inherently difficult nature of NPS pollution management. It is an inter-governmental and cross-jurisdictional issue. No one agency is-or can ever be-assigned all responsibility for NPS water pollution management because so many issues are involved. Improving the clarity of our collective direction and sharing commitment among the regulating agencies is essential to managing NPS pollution. This is especially important in dealing with the emerging issues related to land, resource, and growth management. The specific strategies and actions described later in this Action Plan identify the organizations responsible for managing NPS water pollution in an effort to provide clarity on agency roles, and to encourage coordination of management efforts.
The more contaminants in water, the greater the risk to humans, fish, and animals. Even small amounts of contaminants in small amounts of runoff result in cumulative effects over an entire watershed and, building up over time, can have a significant impact. Locating the sources of pollution and removing contaminants before they reach the water provides the best assurance of clean water in the future.
Well planned and properly managed human settlement and industrial development are immensely important to preventing NPS water pollution. Expanding development provides opportunities for numerous non-point sources of water pollution, such as construction site runoff, storm drains, spills and leaks, atmospheric deposition, and onsite sewage systems. New developments may affect previously pristine waters. The cumulative effects of creeping development may push surface and ground waters beyond their capacity to assimilate contaminants, creating impacts that are out of proportion to the size of the newly-developed area. In its initial stages, land development can result in loss of green space, decreased pervious surface area, diversion and channelization of streams, destruction of aquatic habitat, and removal of riparian vegetation-all elements of natural systems that buffer, filter, and purify water and provide cover and food for fish. One federal report estimates that in the lower Fraser Valley, natural wetlands comprised nearly one-third of all lands converted to urban use between 1967 and 1982. In the Lower Mainland, more than 600 hectares of rural land are converted to urban uses every year. Between 1981 and 1986 the urban area of Greater Vancouver grew by 34 km2, more than eight times the area of Stanley Park. Land clearing and excavation can cause extensive erosion. Sediment loads from erosion on construction sites can be 10 to 20 times greater than those from cultivation. When land development is complete, impermeable roads, sidewalks, driveways, parking lots, and rooftops dramatically increase the volume and rate of surface runoff, creating the potential for more severe erosion and flooding. Some of the more significant impacts caused by poor land development practices include increased water treatment costs, reduced recharge of aquifers, interference with navigation and recreation, flood damage and erosion, and destruction of aquatic habitat for fish and wildlife. Construction activities can also introduce pollutants such as phosphorus, nitrogen, petroleum products, organic chemicals, metals, and sediments, which eventually find their way into adjacent waterbodies. The serious damage that land development can have on aquatic ecosystems is illustrated by the fact that Vancouver once had more than 60 productive salmon streams, and now has only six. Another
effect associated with expanding urbanization is an increased
potential for hydrocarbon spills and leaks into waterbodies,
ranging from the very large (a tanker spill) to the very
small (dripping gasoline during vehicle and boat refuelling).
Chemicals typically spilled (accidentally or deliberately)
into storm drains from residential or commercial sources
include paint thinners, wood preservatives, engine oil, antifreeze,
pesticides, herbicides, and household cleaners. Spills of
chloraminated drinking water into small streams can cause
major fish kills.
Agricultural operations, if not properly managed, discharge a wide range of contaminants, including those from manure, fertilizers, pesticides, and eroded soil particles. The most worrisome contaminants are ammonia, nutrients, pathogens, and sediments. Ammonia is toxic to fish, while nutrients can impair water quality, as in the Serpentine and Nikomekl rivers, the Okanagan Lakes, and the Abbotsford aquifer. Manure is a significant source of nitrogen, phosphorus, biochemical oxygen demand, and disease-causing organisms, including those responsible for waterborne diseases. Proper management is required to avoid adverse effects to water supplies and human health.
Pesticides
can contaminate waterbodies by several routes, including
spillage, improper storage, application too near or into
ditches and streams, leaching from soils, or washed away
in runoff. About $22 million per year is spent on application
of 120 different types of pesticides in British Columbia.
The area of provincial agricultural cropland treated with
pesticides increased from about 425,000 hectares in 1971
to about 550,000 hectares in 1986-about a 30% increase. On
Crown land, the use of pesticides has stabilized or decreased
in the last few years, suggesting that the promotion of integrated
pest management in British Columbia since the 1980's may
be paying off. Integrated pest management is an ecological
approach to pest management where all available control technologies
are consolidated into a unified program aimed at preventing
economic damage and adverse effects to human health and the
environment.
Urban development changes the hydrology (water flow amounts and patterns) of an area. Where natural vegetation and soil structure once allowed the gradual absorption and slow through-put of rain and snowmelt, paved streets and buildings speed delivery of both water and pollutants to our waterways. Pollutants from commercial, industrial, and residential activities that may appear insignificant at their source are transported by rain and snowmelt into storm drains that flush the wastes into rivers, lakes, or marine waters. In developed areas, surface runoff is increased by changes in slope due to landscaping and increasing impermeable surface area of pavement and buildings. Contaminants accumulated during dry periods are picked up by the next rainfall and quickly moved to the drainage system. This is when discharges can be most dangerous, because "first flush" concentrations of toxins are high. Some city residents have come to expect regular closure of favourite beaches. Less publicized but equally significant are the effects on aquatic life caused by metals and other toxic compounds that accumulate in sediments. Ordinary citizens contribute to polluted runoff in many ways, often without realizing it. Car washing and maintenance can release salts, anti-freeze, and oils onto the pavement and then into storm drains and ditches. Pollutants from vehicle exhaust and backyard burning eventually settle to the ground and are washed into adjacent waterbodies by the next rainfall. Households with lawns or gardens use more chemicals on a given area than commercial growers. Half of all households with yards in British Columbia use fertilizers and one-quarter use pesticides. Excess amounts of these compounds find their way into the soil, ground water, and adjacent surface waters.
Highway
stormwater runoff combines the worst of industrial and residential
runoff in the variety and concentration of metals, particulates,
and petroleum compounds deposited by vehicles. Although stormwater
runoff is generally more contaminated in urban areas, it
also poses concerns in towns and rural areas, where erosion
and sedimentation from roads, road-dust abatement chemicals,
and road salt contribute to pollution.
There are still about 250,000 onsite sewage systems in British Columbia, despite expansion of municipal sewage collection and treatment facilities. Onsite systems that are poorly planned, constructed, or maintained present substantial threats to water quality in the province. Discharges from failing onsite sewage treatment facilities are a primary source of fecal contamination containing pathogenic organisms (bacteria, viruses, and protozoa). Nutrients (nitrogen and phosphorus) can also be problematic. The soil around the system removes the nutrients, and the degree of effluent remediation depends on soil texture and chemistry, the depth of unsaturated zone, and the distance of the system from receiving waters. Seepage from onsite systems can infiltrate sources of drinking water (including aquifers, streams, and lakes), cause health risks for swimmers and consumers of contaminated shellfish, and disrupt aquatic ecosystems by poisoning aquatic organisms and causing excessive growth of aquatic vegetation. The Sewage Disposal Regulation under the provincial Health Act sets requirements for the design and construction of septic tanks and other onsite sewage systems of less than 22.7 m3/d, and defines acceptable soil conditions for the location of disposal fields. In 1985, more stringent regulations to control NPS pollution from onsite sewage disposal were introduced in the Okanagan, but these regulations do not apply to systems installed before 1985, or those situated elsewhere in the province. Moreover, the main objective of the Sewage Disposal Regulation is to prevent health hazards, not to address the environmental impacts of nutrient pollution. The Regulation has no enforcement provisions if operators fail to service onsite sewage disposal facilities, and no ongoing inspection efforts are being made. Alternative sewage disposal systems are available to replace conventional onsite systems. These systems can stand alone or be used in combination with conventional systems. They not only can reduce the impact of the conventional onsite sewage disposal systems on water quality, but can reduce the amount of waste produced. Alternative sewage disposal systems can produce high quality effluent, conserve water through low usage, and recycle grey water (i.e., water from residential sinks and washing machines).
British
Columbia's forest sector accounts for 7.5% of the province's
gross domestic product and 60% of all exports. Much of the
land is harvested by clearcutting, a method which can cause
substantial soil erosion, particularly in rainy areas, and
higher accumulation of snow than if trees were left standing.
When warm spring weather arrives, higher-than-normal snowmelt
can cause elevated sediment levels in the water. In addition,
there are over 37,000 kilometres of logging roads throughout
the province, far exceeding the length of the provincial
highway system. Logging road construction, use, and maintenance
are the primary causes of NPS water pollution from forestry
activities, causing up to 90% of the sedimentation from forestry
activities.
To address concerns over forestry and range activities in British Columbia, the provincial government legislated the Forest Practices Code of British Columbia Act in 1994. The Code includes standards and requirements for forest planning and development, and measures for conserving biological diversity, soil, water, fish, wildlife, scenic diversity, and other forest resources. With the implementation of the Forest Practices Code, BC is in the forefront of managing forestry-related NPS pollution issues. The Code recognizes water quality, quantity, and timing of flow as principle values in watersheds. The Act, and its regulations and standards protect watersheds-and consequently water quality-by guiding and regulating forest resource activities. Gases and particulates released to the atmosphere from combustion sources such as motor vehicle emissions, slash burning, and industrial sources, contain nitrogen, sulphur, and metal compounds, which eventually settle to the ground as dust or fall to the earth in rain and snow. These pollutants, which may have distant origins, may be deposited directly into waterbodies, filter slowly into ground water, or in urban areas, be washed from roads, rooftops, and parking lots into surface waters. The gradual effect can be acidification of waters to a point where the natural buffering capacity of receiving waters is exceeded and aquatic life is threatened. Toxins, such as dioxins, furans, polychlorinated biphenyls, and polycyclic aromatic hydrocarbons, transported by atmospheric processes eventually accumulate in sediments, to the detriment of bottom-dwelling organisms and fish and their consumers. Automobile
use in an area greatly affects the atmospheric deposition
of NPS pollutants, and this is a concern linked to urban
sprawl. British Columbia's Lower Fraser Valley, with its
characteristic weather patterns and surrounding mountains,
now has a serious air quality problem because of ever-increasing
motor vehicle use. In the Greater Vancouver area between
1984 and 1991, the number of cars insured for driving to
work increased twice as fast as the population. Greater Vancouver
now has more cars per capita than Greater Los Angeles.
An expanding population, expected to reach three million in the Lower Mainland by 2021, could mean a doubling of vehicle-kilometres travelled in the region. Greater congestion will lead to more stop-and-go traffic, increasing the emissions released per trip. From both an air quality and a water quality perspective, the increased risk to human health of these projections is of concern, given that the Lower Fraser Valley airshed is now at or above its capacity to accept contaminants. Significant efforts are being made to address these issues in British Columbia, especially to ensure the use of clean vehicles and fuels. Recent programs include:
Several legislative initiatives have also been completed:
On-going efforts to manage point sources of air discharge, regulating toxins in motor vehicle emissions, and above all, reducing overall motor vehicle use are important strategies and will help address this source of NPS water pollution in British Columbia.
Boat operation and maintenance, discharge of sewage and grey water from vessels, and aquaculture operations are all sources of fresh and marine water NPS pollution. Although national legislation prohibits the discharge of garbage and pollutants from ships into Canadian waters, the legislation does not apply to sewage discharges in most locations. Sewage discharges in shallow, enclosed waters with poor flushing can impair water quality and recreational water use, and raise health concerns if the receiving waters are used for drinking water, swimming, or support shellfish. Under
the Canada Shipping Act, the Pleasure Craft Sewage Prevention
Regulation mandates that any pleasure craft with toilet facilities
must have sewage retention capabilities (holding tanks) to
prevent sewage discharge when operating in designated waterbodies.
This designation is important for waterbodies where high
quality water is needed for fish/shellfish, swimming, or
drinking water. British Columbia has asked the Canadian Coast
Guard of Fisheries and Oceans Canada to designate about 60
additional fresh and marine waterbodies under this Regulation
to prohibit sewage discharge and it is expected that more
waterbodies will be designated in the future.
Last content update: August 3, 2001
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