June 2010

For more information, call:

picemail.moe@ontario.ca
Website: Ministry of the Environment and Climate Change

1. Introduction

Phosphorus is a key water quality concern in Lake Simcoe. The Lake Simcoe Protection Plan (the Plan) commits the Province, working with the Lake Simcoe Region Conservation Authority (LSRCA), local stakeholders, municipalities and other partners, to develop a comprehensive Phosphorus Reduction Strategy (the Strategy) in Year One of the Plan – by June 2010. This Strategy is critical to achieving the ambitious and aggressive reductions in phosphorus needed to restore the Lake’s water quality and ecological health and builds on the tough measures in the Plan.

This map shows the boundaries of the Lake Simcoe watershed as defined under the Lake Simcoe Protection Act. The boundary encompasses parts of the Town of Innisfil, the Town of Bradford-West Gwillimbury, the Township of Brock, the Township of Scugog, the Township of Uxbridge, the Township of Oro-Medonte, the Town of Whitchurch-Stouffville, the Town of Aurora, the Township of King, the City of Barrie, the City of Orillia, the Township of Ramara, the Town of New Tecumseth, and the City of Kawartha Lakes as well as the whole of the Town of Newmarket, the Town of Georgina, the Town of East Gwillimbury, and all islands within Lake Simcoe.

This document has been informed by the long history of scientific research and planning work by the Province, municipalities, the conservation authority and community groups. This critical work continues and the Province has committed an investment of $20 million in support of it. For a detailed discussion of ongoing research and scientific work, including timelines for completion, please refer to Chapter 7 in this document.

We don’t have all the answers or solutions now, but tough decisions and choices must be made today to get there for future generations.

This Phosphorus Reduction Strategy is a living document. It will be reviewed and updated a minimum of every 5 years.

Policy 4.24-SA of the Plan identifies the parameters for this Strategy. They include but are not limited to:

  • A phased, coordinated and adaptive management approach – because research is ongoing the Strategy will become increasingly more detailed and stringent in its requirements over time. It will be amended and updated regularly to ensure our path is the right one;
  • An assessment of sources or sectors that contribute phosphorus loadings to the watershed – who is contributing and how much;
  • an identification of practical and effective actions that should be taken to address each source or sector – many successes have been realized in the last twenty years and we are building on those, but more specific and challenging demands must be placed on those who contribute phosphorus to the Lake; and,
  • a long term total phosphorus loading cap for each sewage treatment plant in the Lake Simcoe watershed – future growth in the watershed is putting greater demands on these plants and they must utilize the best available technology to manage more sewage at a higher level of treatment.

Getting Here…

Lake Simcoe is the largest lake in southern Ontario aside from the Great Lakes, and has played an important role in provincial history. For hundreds of years, it served as a transportation link for Ontario’s First Nations and Métis communities, fur traders and the logging industry. During the 20th century, the human population in the watershed grew rapidly, and Lake Simcoe now provides drinking water for eight municipalities. It also supports a successful tourism industry that provides outdoor recreational opportunities for tens of thousands of people every year. Agricultural land use accounts for 47% of the watershed, generating millions of dollars in production a year.

Over the past two centuries, human activities have had a significant impact on Lake Simcoe’s water quality, and have also changed the natural landscape and compromised the Lake’s delicate ecosystem. These impacts have become a serious environmental concern, and addressing them is a provincial priority.

Efforts to restore Lake Simcoe by improving water quality have been on-going since the 1980s. The Lake Simcoe Environmental Management Strategy (LSEMS) program, which started in 1981, focussed on controlling and reducing phosphorus inputs to the Lake, through a multi-agency partnership of provincial ministries, the Lake Simcoe Region Conservation Authority, municipalities, the Federal Government and the Chippewas of Georgina Island First Nation. The valuable research and results that came from the LSEMS program were used by the Lake Simcoe Science Advisory Committee and helped inform the priorities set out in the Lake Simcoe Protection Plan released in June 2009.

Following the efforts of the LSEMS program, the theme of partnership and shared responsibility continued when the Province, the Lake Simcoe Region Conservation Authority, and the 19 municipalities in the Lake Simcoe area produced the Intergovernmental Action Plan (IGAP) for Simcoe, Barrie and Orillia in 2006. One of the key results of IGAP that links to this Strategy is the completed Assimilative Capacity Study and associated modeling tools for the Lake Simcoe watershed. Assimilative capacity is the relationship between water quality and quantity, land use, and the capability of a lake to resist the effects of landscape disturbance without impairing water quality. The results of that study helped to inform parts of the sections below.

With the passage of the Lake Simcoe Protection Act, 2008 and the resulting Lake Simcoe Protection Plan (the Plan), the Province signalled its commitment to address long term environmental issues in Lake Simcoe and its watershed. The Plan takes a comprehensive approach to improving environmental conditions in the Lake and its watershed by addressing a number of key environmental problems, including:

  • stresses from human activities;
  • stresses from excessive levels of phosphorus;
  • loss or disruption of sensitive natural areas and fish and wildlife habitat; and,
  • water quality and quantity changes that interfere with natural ecosystems and affect the amount and the quality of water available for human consumption.

Under the Plan, the Provincial government and its partners continue to conduct research and monitoring work and taking action to improve environmental quality throughout the watershed. These activities are designed to strengthen protection for shorelines and natural heritage, reduce pollution and implement stewardship measures that ensure the Lake and its resources will continue to be enjoyed by future generations. The Plan can be accessed on the Internet at the Ministry’s Lake Simcoe webpage.

Message from The Chippewas of Georgina Island First Nation:

The Chippewas of Georgina Island First Nation have always had a special relationship with Lake Simcoe. It affects almost every aspect of this community’s daily life. The water is Mother Earth’s life blood, and it must be protected. In the past decade, Georgina Island First Nation has independently taken the lead and completed an overhaul of over 280 septic systems on Snake and Fox Islands. We are currently partnering with Georgian College Barrie campus to conduct a point and non-point source pollution reduction project for all three islands. We will be continuing on with such projects as our species at risk identification, rehabilitation and mapping, and our shoreline and fish habitat restoration around Georgina Island. Other strategies included planning and facilitating workshops and information sessions for members and cottagers alike and encouraging them to take part in the Phosphorus Reduction Strategy. The health of Lake Simcoe has a great impact on this First Nation community and The Chippewas of Georgina Island strongly support the Lake Simcoe Protection Plan and its initiatives.

Phosphorus in the Lake Simcoe Watershed

Phosphorus occurs naturally in the environment, and is an essential nutrient that plants and animals need. In rivers and lakes, phosphorus occurs either in a dissolved form or as a solid attached to soil and other particles in the water. Natural heritage features, represented by the forests, wetlands, lakes, rivers and grasslands that cover our landscape, are vital components of the ecosystem that naturally help to regulate the entry of phosphorus into the watershed by preventing soil erosion, stabilizing shorelines, filtering and retaining phosphorus and other nutrients in plant tissue. Scientists estimate that, prior to the major settlement and land clearing that took place in the watershed in the 1800s, the annual phosphorus load going into the Lake was about 32 T/yr, which is less than half of what it is today. Since then, the watershed has continued to face increasing pressures from a growing human population. The average phosphorus load to Lake Simcoe from 2002-2007 was 72 T/yr.

Because phosphorus is a nutrient, high levels in the Lake encourage the growth of plants and algae. When the plants and algae die, they sink to the bottom and decompose in a process that uses up oxygen. When the plant life is abundant, as it is now, the decomposition creates an oxygen shortage in the deeper areas of the Lake—areas that provide vital habitat for the coldwater fish species that live there, such as lake trout and lake whitefish. Although there is more oxygen available now than there was 30 years ago, the oxygen content in these deep, cold parts of the Lake is still too low to allow Lake Simcoe’s coldwater fish community to sustain itself.

To improve the water quality of Lake Simcoe and to protect coldwater fish species, the Plan sets a deep water dissolved oxygen target of 7 mg/L (See “Targets” in Chapter 4 of the Plan). Current research suggests that this level is required to support a naturally reproducing, and self-sustaining, lake trout population. Based on current science, this target translates into an annual phosphorus load of about 44 T/yr, about 40% less than the current load. The Phosphorus Reduction Strategy is intended to serve as a long term framework to reach this target.

The phosphorus issue is not just about a healthier future for Lake Simcoe’s cold water fish community. Millions of dollars in tourism business, tens of thousands of jobs, safe, clean drinking water for local communities and the quality of life throughout the region depend on a healthy Lake Simcoe watershed. Scientists, municipalities, the Provincial government, the Lake Simcoe Region Conservation Authority and stakeholders all agree that urgent action is needed to reduce the annual phosphorus loadings in Lake Simcoe — to mitigate the damage from the past, and to ensure that the Lake and its watershed enjoy a healthier, more sustainable future.

About the Phosphorus Reduction Strategy

The Phosphorus Reduction Strategy is based on a vision of shared responsibility and the continual reduction of phosphorus loading in Lake Simcoe over time – a long term, phased approach. The actions required under the Strategy are a starting point and initial planning tool. They are designed to achieve proportional reductions from each major contributing source so that the proportional contribution each source makes to the 72 T/yr total load today will be the same proportional contribution it makes to the 44 T/yr goal in the future. This proportional reduction approach will be reassessed in five years (2015) to ensure that the approach makes the most sense based on new science and information that becomes available as a result of ongoing and future research initiatives. Should adjustments be required, or should accountabilities for contributions change, the Strategy will be adapted to best reflect this.

Figure 1: Phosphorus Reduction Targets

This bar graph shows the current (2010) phosphorus loading to Lake Simcoe in tonnes per year, broken down by proportional contributions from Atmospheric Deposition, Septics within 300 metres of the Lake, Holland Marsh and smaller polders, Agriculture and septics on streams, urban source, and sewage treatment plants. It shows that adaptive management will be required from 2025 to reach the target of 44 tonnes per year by 2045

Enlarge this image.

The Strategy is based on the following guiding principles:

  1. Build on the scientific monitoring and research undertaken to date in order to set realistic, intermediate goals for reducing phosphorus, using the best scientific information currently available to predict and mitigate the environmental impacts of all pollution sources.
  2. Focus first on achieving phosphorus reductions at their source, and then work to reduce the phosphorus released into the environment. Examples of these actions may include installing permeable pavement to encourage the natural filtration of water through the ground or planting trees and native plants along a stream bank to take up phosphorus before it enters the stream.
  3. Set short and long term goals that target reductions from all sources, proportional to their contribution.
  4. Consider the relative costs and benefits of the phosphorus reduction options; and, the investment and contribution needed by those responsible for source reductions.
  5. Continuously improve and adapt – as science advances actions needed will become more stringent and specific.

For each major source or sector, the Strategy identifies specific reduction goals and potential reduction opportunities that will work towards achieving the whole-lake goal of 44 T/yr. In addition to identifying specific reduction targets for each source, the Strategy incorporates several key concepts and strategic directions from the Plan, including:

  • Adaptive Management;
  • Watershed Approach;
  • Stewardship and Community Action;
  • Source-specific Actions;
  • Monitoring and Compliance; and,
  • Research, Modelling and Innovation.

These concepts and strategic directions are described in the remainder of this document.

It is important to note that reaching the whole-lake goal of 44 T/yr will require continued stewardship efforts, targeted research, innovative new technology for wastewater and stormwater management and a commitment to managing the watershed and its resources in an integrated and sustainable manner. The key to achieving our long term goal lies in evaluating and adapting the approaches of the Phosphorus Reduction Strategy as new advances in science and technology occur and in the success of the actions outlined here.

The ministry is incorporating “strategic directions” in the Phosphorus Reduction Strategy to set out actions to be taken to reach the goals.

Protecting Lake Simcoe and reducing the phosphorus load to the Lake is a priority; the realization of this goal requires a balanced approach which must acknowledge the anticipated population and employment growth in the watershed as well as the expense required to implement the actions recommended in this document. But what could happen if we don’t take action now?

Figure 2: Past, Present and Future Phosphorus Loads to Lake Simcoe

This graph shows that the estimated natural phosphorus load to Lake Simcoe in the 1800s was about 30 tonnes per year. By the 1980s it had climbed to over 100 tonnes per year, and is currently between 70 to 80 tonnes per year. Without action, the phosphorus load could increase to 94 tonnes per year by 2045.

Figure 2 shows the past, present and future phosphorus loads to Lake Simcoe. Without a commitment to sustained action today, and by accommodating the anticipated population and employment growth in the Lake Simcoe watershed into the future, the phosphorus load could increase to 94 T/yr. The Strategy sets out actions and directives to be undertaken between now and 2045.

What have we achieved to date?

It is important to recognize that actions have already been taken through the Lake Simcoe Environmental Management Strategy (LSEMS) over the past 25 years to reduce phosphorus loading in the Lake. It is estimated that the phosphorus load has been reduced from over 100 T/yr in the 1980s to the current load of 72 T/yr (see Figure 2 above). Some of these actions that helped achieve this success are highlighted below:

  • LSEMS resulted in the launch of animplementation program in 1990 in three phases:
    • Phase I – 1990-1994: Total phosphorus loading caps imposed on sewage treatment plants (STPs)
    • Phase II – 1995-2000: “Enhanced” or “Level 1” stormwater treatment required for all new urban development
    • Phase III – 2001-2008: Expansion of stewardship projects and enhanced focus on community engagement.

Other more recent actions that have been undertaken and are ongoing in the watershed are described below:

  • A study is currently underway to help inform the relative costs and merits of Low Impact Development (LID) practices to achieve phosphorus reductions.
    • LID refers to practices which are used that mimic the natural flow and behaviour of water as it runs off developed areas, such as permeable pavement or green rooftops.
  • 160 stormwater retrofit opportunities have been identified in the watershed to reduce approximately 4.2 T/yr of phosphorus, such as retrofitting quantity ponds into water quality ponds.
  • Agricultural and rural stewardship programs have been successfully implemented with over 500 on-farm projects completed or underway. These include the LSRCA's Landowner Environmental Assistance Program, the Canada-Ontario Environmental Farm Plan programs and the Lake Simcoe Farm Stewardship Program. Some examples of practices to help reduce phosphorus include:
    • Fencing cattle;
    • Appropriate manure storage; and,
    • Cover crops.
  • Best Management Practices (BMPs) to reduce the phosphorus load from polders are currently being implemented in the watershed in areas such as the Holland Marsh. These BMPs include companion cropping to reduce wind erosion, bank stabilization and irrigation and nutrient management.
  • Atmospheric deposition studies are currently underway to better understand where airborne phosphorus is originating from and how much is being deposited in the watershed.
  • Ongoing research and modelling is underway in a number of areas, including the development of subwatershed targets for phosphorus loading, improvement of water quality models and the ongoing evaluation of the whole-lake goal of 44 T/yr.
  • A pilot project to test Phoslock™ a phosphorus reduction product, is underway in Newmarket and the Holland Marsh. The Phoslock™ product is mixed with water and applied to a water body, where it binds the phosphorus within the product.
  • A pilot project to examine the potential of a red sand filtration chamber to remove phosphorus from urban stormwater runoff is currently underway in the watershed.
  • A project is currently underway to evaluate the feasibility of reusing treated wastewater effluent and stormwater runoff.

2. Adaptive Management

Adaptive Management means continuously improving a series of actions over time. It means learning from the outcomes of past actions and decisions, adjusting our course where it makes sense and continuing to move forward. This is one of the principles outlined in the Plan and endorsed by the Lake Simcoe Science Advisory Committee. The Strategy adopts the principles of adaptive management through the following key elements:

  • taking immediate action, based on the best available scientific information, that builds on past actions to ensure continuous progress;
  • setting, evaluating and measuring progress towards targets and goals as knowledge advances over time;
  • pursuing scientific monitoring and modelling to expand and improve on the information available;
  • supporting research and innovation to improve the solutions available for reducing phosphorus; and,
  • incorporating new scientific information and innovative technology as it becomes available, to improve actions and enhance results over time.

Our approach to reducing the phosphorus load from atmospheric deposition is an example of how we will manage and adapt the Strategy over time. Overall, atmospheric deposition accounts for a significant portion of the annual phosphorus load to Lake Simcoe, but we don’t know the exact sources and quantities from those sources. For example, we know that promoting and implementing effective and practical best management practices (BMPs) will reduce soil erosion and address some of the atmospheric deposition. While these best management practices are promoted throughout the Plan and the Strategy, the research currently underway will help us to refine our understanding of the sources of atmospheric deposition and to prioritize our actions accordingly.

As part of the progress reports required every five years under subsection 12 (2) of the Lake Simcoe Protection Act, 2008, the Ministry of Environment will report on:

  1. the implementation of the strategic directions set out in the Strategy;
  2. the extent to which the phosphorus reduction goals established in the Strategy are being achieved;
  3. the progress being made to achieve the overall long term phosphorus loading goal of 44 T/yr; and,
  4. whether the Strategy should be revised to incorporate the results from ongoing research, monitoring and innovation.

3. Watershed Approach

In 2006, Ontario adopted an innovative, watershed-based approach to managing drinking water resources, through the Clean Water Act, 2006 (CWA). The Strategy utilizes this approach to manage the phosphorus load in Lake Simcoe by looking at problems and pursuing solutions across the entire watershed, which includes Lake Simcoe itself, rivers and streams that drain into it and the natural heritage features that surround it.

Under this approach, the Province and its partners will develop “subwatershed” phosphorus loading targets that add up to the whole-lake goal of 44 T/yr. The research, modeling and monitoring work that is currently under way will help to establish these subwatershed targets and fine-tune priorities for action. It is anticipated that the subwatershed targets will be available in the spring/summer of 2010.

Figure 3: Watershed (copyright LSRCA)

Figure 3 is a painting illustration of a watershed.

What is a watershed?

A watershed is the area of land that drains into a stream, river, or lake. The Lake Simcoe watershed is the total area of land that drains into Lake Simcoe. It drains either directly into the lake, or into a connecting stream or river (known as a tributary) that then flows into the lake. Each tributary has its own smaller area that drains into it called a subwatershed.

In the meantime, immediate actions are needed to address the phosphorus problem in the Lake Simcoe watershed. Based on existing research, the major sources of phosphorus loading identified to date are as follows:

  • Sewage Treatment Plants (STPs);
  • Watershed streams or tributaries that include the runoff from urban, rural and agricultural areas in the watershed;
  • Atmospheric Deposition which is phosphorus that is deposited directly onto the surface of the Lake;
  • Septic (on-site sewage) systems; and,
  • Drainage water from the Holland Marsh and smaller polders, which are former wetlands that were drained so that the rich soils could be used for agriculture.

The following graph in Figure 4 shows the main sources of phosphorus in the Lake Simcoe watershed and the average annual load from each source over a five-year period from 2002 to 2007. The average total load during that period was 72 T/yr. More information on these sources and how they are measured is available in the Report on the Phosphorus Loads to Lake Simcoe 2004-2007, which includes the historical loads from 1998 to 2007, and is accessible on the Internet at the Ministry’s Protecting Lake Simcoe webpage.

Figure 4: Lake Simcoe Phosphorus Sources

This pie chart shows the relative contribution of the primary contributing sectors to Phosphorus loading in the Lake Simcoe watershed. Watershed Streams contribute 41 tonnes per year or 56%, Atmospheric Deposition at 19 tonnes per year or 27%, Sewage Treatment Plants at 5 tonnes per year or 7%, Septics at 4 tonnes per year or 6%, and the Holland Marsh and smaller polders at 3 tonnes per year or 4%.

(Source: Lake Simcoe Region Conservation Authority and Ministry of the Environment Data sets on phosphorus loading for 2002 to 2007)

Natural Heritage

Natural heritage features contribute to the reduction of phosphorous on a number of levels. Healthy features, such as wetlands, woodlands and riparian areas, help to regulate water quality by filtering contaminants and retaining excess nutrients before they reach water sources. The trees, shrubs and grasses in and around watercourses act as buffers, preventing pollutants from getting into surface water and trapping sediment that can otherwise affect water quality. These buffer areas also provide habitat and bank stability, preventing erosion and stabilizing shorelines. The loss of key natural heritage features and shoreline areas along Lake Simcoe has impaired the ability of the natural heritage system to perform these multiple functions.

The protection and enhancement of the watershed’s natural heritage features will foster a resilient, adaptable and sustainable watershed and contribute to the overall ecological health of Lake Simcoe. The Plan promotes a consistent approach to the protection, enhancement or restoration of the Lake Simcoe shoreline and of key natural heritage features. It further identifies a number of actions to meet natural heritage targets including: no further loss of natural shorelines; greater proportion of natural vegetative cover; protection of wetlands; establishing naturalized riparian areas; restoring natural areas or features; and, increased ecological health based on the maintenance of natural biodiversity. These actions, many of which can be achieved through education and stewardship actions and proper land management practices, will further help to reduce phosphorus loading in the watershed.

4. Stewardship And Community Action

The Lake Simcoe Protection Plan recognizes education and public engagement as essential ways to promote community-based stewardship and to address many of the impacts and threats to the Lake Simcoe watershed, including phosphorus reduction. This is particularly true for promoting individual actions that require behavioural changes or changes in habits, and where regulations have been shown to be difficult to develop, implement and enforce.

Voluntary stewardship, through education, community engagement and cost-share incentives, when possible, helps to foster an improved understanding of a shared connection to, and an increased responsibility for, environmental protection by promoting collective, cumulative actions and behavioral changes that help reduce phosphorus inputs to the watershed over the long term.

Since the majority of the watershed is privately owned and managed by individual residents, businesses and industry, the opportunities for phosphorus reduction are directly dependant on the actions of those who are responsible for managing these private lands.

Stewardship Defined

  • Voluntary process of sustained attitude and behaviour change over time
  • Multiple elements and activities by numerous individuals and organizations

Together,

  • Awareness
  • Education
  • Training
  • Influence

Creates understanding and desire to participate.

  • Partnerships
    • trust; support
    • effective delivery
  • Science-Based
    • Risk Assessment
    • Action Plans
    • Priority Setting

Overcomes barriers and builds skills.

  • Technical assistance
  • Incentives to:
    • Change behaviour
    • Make improvements
    • Innovate
  • Recognize & measure progress and success

Promotes actions that can be supported and reinforced.

  • Many Activities
    • Best Management Practices
    • Remediation & Restoration, e.g. tree planting, buffers
  • Many Beliefs
    • Conservation Ethic, e.g. land easements, parks
    • Citizen participation

Efforts and results cut across policy boundaries. Altogether,

  • Effective and proven approach to stewardship
  • Ecological, economic and social benefits
  • Continuous improvement over time
  • Opportunity to align stewardship with Lake Simcoe priorities

Challenge to measure stewardship’s direct impact.

Education and community engagement programs to promote stewardship have a long history of success in the Lake Simcoe watershed and have helped to reduce the total phosphorus load in the past, prior to implementation of the Plan. Some of those actions include reforesting of eroding landscapes in the early 1920s, the establishment of field naturalist and conservation clubs in the 1930s and fish stocking and water quality monitoring in the 1950s. Stewardship promotion has been particularly evident in the past 20 years, since the introduction of the Canada-Ontario Environmental Farm Plan Program and other environmental and cost-share programs, such as those offered by the LSRCA. The Chippewas of Georgina Island First Nation have demonstrated leadership in stewardship promotion including septic system upgrades, community-based mapping and participation in several programs including the Clean Marina Program. As the Phosphorus Reduction Strategy moves forward, stewardship activities will be vital to the success of the Province’s objectives for the long term health of the Lake Simcoe watershed.

The ministries of Natural Resources, Agriculture, Food and Rural Affairs, and Environment, along with the LSRCA, will develop a stewardship strategy that will help to align stewardship programming in the watershed and to identify and continue to build and encourage best management practices in every sector. The stewardship strategy will also identify opportunities for public education and stewardship in the watershed to ensure that they continue to enhance and achieve the goals for phosphorous reduction and other environmental priorities. We will communicate with, and reach out to the public on what they can do to help us reach our targets. We will review and report on our stewardship programming every two years and develop performance measures so we can measure our success.

Best Management Practices Opportunities

The LSRCA conducted a Best Management Practices Opportunities Inventory, spanning 17 of the 18 subwatersheds within the Lake Simcoe basin. The purpose of this was to identify opportunities for restoration and stewardship projects to improve the health of Lake Simcoe from the reduction of phosphorus inputs from rural and urban sources as well as other related ecosystem health aspects.

Over two field seasons (2008-09), BMP field technicians investigated 1,652 kilometers of stream within the Lake Simcoe basin. The BMP Inventory identified 4,814 locations documenting 17,125 BMP opportunities for restoration and remedial works, including: the improvement of fish habitat through the correction of existing or potential erosion sites; the enhancement of riparian vegetation buffers; and the removal of barriers. Common examples of opportunities identified include poor riparian cover, stream bank erosion, improper culverts and many more.

This detailed inventory clearly shows that there are significant opportunities to reduce phosphorus loading and improve ecosystem health. The information is stored in a comprehensive database that includes the location, site details, photographs and other pertinent information for each opportunity. The database can be searched to provide all of the opportunities by subwatershed, municipality, or opportunity type as well as other custom searches. This is a great tool to assist stewardship staff to prioritize opportunities as well as to track implementation. This successful project was funded by the LSRCA, York Region and the Lake Simcoe Clean-Up fund. A full version of the report can be found by visiting the LSRCA website.

Phosphorus Sources

Although phosphorus is an essential nutrient for all living things, too much impairs water quality. There are many sources of phosphorus inputs to Lake Simcoe, described in detail in the following chapters.

Some phosphorus comes from specific point sources, such as a sewage treatment plant or stormwater outfall. Some phosphorus enters the Lake through diffuse, or “non-point sources”, as a result of landscape conditions and day-to-day land-use practices in urban and rural areas. While some of this diffuse phosphorus loading is natural, much of it can be better managed by the practices of individuals and businesses throughout the watershed.

Some examples of “non-point” phosphorus sources include:

  • Fertilizers used on agricultural lands, residential properties, and public lands such as parks and roadside plantings, and new urban developments;
  • Household septic systems;
  • Animal waste (including livestock, pets, and wildlife such as geese);
  • Stormwater runoff (from city storm drains and rural or agricultural ditches);
  • Household cleaners (e.g. dishwasher and car washing detergents containing phosphorus);
  • Stream bank and shoreline erosion and erosion from bare soils (e.g. farm fields, subdivision developments under construction) during storm events;
  • Dust from construction areas, pits and quarries, agricultural lands, construction sites and rural roads;
  • Output from food production and other facilities where phosphorus is added to products as a filler, emulsifier or stabilizer; and,
  • Through natural landscape processes where phosphorus ‘leaks’ from the landscape, including forested areas, or ‘flushes’ at certain times of the year, such as during spring snow melt.

Measuring the precise contribution of non-point sources of phosphorus is difficult, but we have an idea of how much of an impact one person can have by making some simple changes (see Table 1 below). Stewardship relies on individual and community-based behavioural changes and the adoption of good practices. This takes a long term, sustained approach, through education and engagement that targets behavioural change so that it becomes the new norm over time. Stewardship programming has the largest impact when good practices are adopted by many.

Table 1: Comparison of How Much Phosphorus Used in Two Households (in 90 days)
SourceHousehold 1 - Phosphorus Used (in grams)Household 2 - (with Recommended Changes)Net Decrease (in grams)
Human waste535 gNone0 g
One load of dishes in the dishwater, per day… using powdered detergent650 gSwitching to phosphate-free detergent650 g
Fertilizing a 30 m × 30 m lawn, once per year, with a fertilizer containing 10 % of each of the following: nitrogen, phosphorus and potassium1,960 gNo fertilizer or compost; natural landscaping1,960 g
Lot cleared of trees increases runoff30 gLeave trees standing10 g
Using commercial household cleaners180 gUsing phosphate-free household products160 g
Total Phosphorus Load3,355 gTotal Phosphorus Load Decrease2,780 g

(Chart adapted from “An Action Guide to Improving the Waters of Lake Simcoe” Lake Simcoe Environmental Management Strategy, Lake Simcoe Region Conservation Authority)

Stewardship and the Lake Simcoe Protection Plan:

The Plan builds on existing stewardship programs (see Appendix C) by recognizing and addressing some key priority needs that include:

  • Enhanced stewardship opportunities for landowners to further encourage action;
  • Improved community support and access to information, programs and incentives;
  • A partnership forum to network, build capacity, coordinate activities and leverage additional resources; and,
  • Common tracking, performance measurement and reporting standards to demonstrate results and the value of stewardship, outreach and education.

Phosphorus Reduction Strategy Strategic Direction #1:

Through the Phosphorus Reduction Strategy, the Province supports the continuation and enhancement of stewardship activities aimed at reducing phosphorus loads. These include:

  • Recognize, celebrate and build on phosphorus reduction successes
  • Remove barriers to participation in stewardship activities
  • Improve coordination to integrate stewardship actions so that neighbours and communities can partner more effectively, share information and promote innovation
  • Link stewardship with research efforts to address knowledge gaps and integrate science and stewardship efforts effectively

Next Steps

The Province will continue to support and build on proven programs and processes, while fostering new ideas and stewardship innovations that will help to address and support phosphorus reduction targets in most of the sectors identified in the Strategy. Specific examples and actions will include:

  • The establishment of a Stewardship Network to foster information sharing, learning, collaboration, recognition and innovation;
  • A watershed survey to assess residents’ needs and address barriers to participation;
  • Facilitating opportunities for the exchange of stewardship and science information to support strategic directions and actions through bi-annual events;
  • Continued support for stewardship programs and their evolution;
  • The development of common tracking, performance measurement and reporting standards to demonstrate results and the value of stewardship, outreach and education;
  • The development of a community awareness and education program for watershed residents, to promote the use of low-phosphate or phosphate-free household products, in line with the goals of the Lake Simcoe Protection Plan, as per Policy 4.26 of the Plan; and,
  • Working with municipalities, businesses and industry to promote and recognize best management practices, innovation and environmental certification.

Stewardship is a community-based process and is most effective when everyone is involved and engaged. Stewardship will continue to be promoted as an essential component to the success of the Plan and this Strategy.

We all share the responsibility…

Addressing the phosphorus problem in Lake Simcoe is a key environmental concern— and everyone can help. Here are nine simple things that you and your family can do to reduce your phosphorus footprint:

  1. Conserve water. Using less water can also help relieve some of the phosphorus load to Lake Simcoe and the rivers in its watershed. By fixing any leaky taps and toilets around your house, installing low-flow faucets and showerheads, watering your lawn less frequently and using a rain barrel to collect rainfall for use in the garden, you can make an important difference. This results in less water needing to be treated in the sewage treatment plants and less runoff going into the Lake and streams.
  2. Check your septic tank. Septic systems around the shoreline of Lake Simcoe contribute an estimated 6 % of the total phosphorus load. That means you need to look after your septic system and make sure it is working properly. That also means not putting anything in there that shouldn’t be in there!
  3. Reduce fertilizer use. Lawn fertilizers that contain phosphorus can wash into rivers and lakes, especially if people use too much of these chemicals. The phosphates from fertilizers are carried into surface waters through storm runoff, with melting snow and from soil erosion. So if you must use fertilizers, make sure the ones you use are phosphorus-free.
  4. Go phosphate-free. Many household products, such as laundry detergent, car washing detergent, dishwasher soap and other cleaning products, contain phosphates that can contribute to the Lake Simcoe phosphorus problem. By purchasing products that are phosphate-free, you and your family can help relieve the environmental pressure on the Lake and its watershed.
  5. Stoop and scoop. Your pet’s waste contains phosphorus and a number of other contaminants. Rainstorms and spring runoff can carry animal waste into sewers and rivers that drain into the Lake—so it’s important to pick up after your pet and dispose of the waste properly.
  6. Plant a tree. Trees and shrubs act as natural filters to stormwater runoff and soil erosion, which contribute to the phosphorus problem. Planting trees and shrubs near the water and along shorelines is especially helpful.
  7. Compost your leaves and food waste to reduce the need for synthetic fertilizer. Fertilizers can pollute the water, promote algae growth and threaten the fish.
  8. Leave your shoreline natural to avoid erosion and preserve the ecosystem. Sediment can clog fish gills and smother aquatic life. It can also carry nutrients like phosphorus into the Lake.

What You Can Do – On the Water

There are many great ways to enjoy Lake Simcoe, including boating and swimming. But make sure your activities aren’t hurting the Lake. Here are four simple things that you and your family can do to reduce your phosphorus footprint.

  1. Be careful when using petroleum products around water. Wipe up any oil spills and dispose of used oil and antifreeze at a marina or gas station.
  2. Use phosphorus-free biodegradable soaps in your boat. Soaps used in boat sinks, showers and dishwashers aren’t treated in a sanitary sewer system when they’re discharged. They can cause more harm than soaps used at home.
  3. When boating, do not produce a wake too close to the shore. It can cause erosion which can pollute the Lake and threaten aquatic life.
  4. Take all your food leftovers back to the shore. Food waste can add phosphorus to the Lake.

If everyone in the Lake Simcoe watershed adopts these simple steps, we can reduce our phosphorus contributions and help improve the water quality and environmental health of our lakes, rivers and streams.

5. Source-Specific Actions

Sewage Treatment Plants (STPs)

Current Load

There are currently 14 municipal STPs and one industrial STP in the Lake Simcoe watershed (shown in Figure 5). Seven of the STPs discharge directly into Lake Simcoe, while the other eight discharge into rivers that flow into the Lake. The average annual phosphorus load from STPs between 2002 and 2007 was about 5 T/yr, which represents about 7 % of the total phosphorus load to the Lake.

Figure 5: Municipal and Privately Owned Sewage Treatment Plants (STPs) in the Lake Simcoe Drainage Basin

This map shows the locations of all of the private and municipal sewage treatment plants in the Lake Simcoe Drainage Basin.

Early Actions

All of the municipal STPs in the Lake Simcoe watershed have had phosphorus loading caps since the late 1980s. As a result, these STPs are among the most effective in Ontario in removing phosphorus. Ten of the 15 STPs are already treating at a tertiary level; nine have conventional tertiary treatment with effluent filtration, and one has advanced tertiary treatment with membrane filtration. In addition, one of the municipalities is also off-setting increases in its phosphorus load from its STP by implementing additional stormwater management controls as new development gets connected. Because of technological progress in treating wastewater, the STPs have reduced their phosphorus loads since the mid-1990s, despite an increase in the total population in the watershed and the larger volumes of wastewater that need to be treated.

STPs in the Lake Simcoe watershed were limited to a maximum phosphorus load of 7.3 T/yr, under the provisions of Ontario Regulation 60/08 (an “Interim” regulation under the Ontario Water Resources Act). This regulation was an interim measure enacted to provide temporary phosphorus loading limits while the Lake Simcoe Protection Plan and the Phosphorus Reduction Strategy were being developed. The limits in the regulation ceased to apply on March 31, 2010, and have been replaced by the phosphorus STP limits set out in this Strategy.

Preliminary estimates based on draft and adopted official plans from municipalities in the Lake Simcoe watershed suggest that by 2031 municipal STPs will need to provide services for an estimated population of approximately half a million people, which is an increase to the current population of approximately 150,000 people. However, since official plan conformity to the Growth Plan for the Greater Golden Horseshoe is still ongoing, the final number of people to be serviced based on the population and employment forecasts by 2031 is yet to be finalized and the above number is subject to change. The population increase would result in increased flows from the STPs and potential increases in the phosphorus load from the STPs, if no limits were put in place.

Related Policies

The Plan has put a number of policies in place to control the potential increase in the phosphorus discharge from STPs throughout the watershed. These policies are listed below:

4.1-DP - For a proposed settlement area expansion, establishment of a new settlement area or a development proposal outside of a settlement area that requires an increase in the existing rated capacity of a sewage treatment plant or the establishment of a new sewage treatment plant, an environmental assessment of the undertaking shall be completed or approved prior to giving any approvals for the proposal under the Planning Act or the Condominium Act, 1998.

4.2-DP - Within one year of the date the Plan comes into effect, the Director shall review and amend the approvals for all sewage treatment plants in the Lake Simcoe watershed to ensure each sewage treatment plant owner and operator is required to do the following:

  1. demonstrate compliance with the Average Concentration Limit for total phosphorus specified in the approval:
    1. at a minimum on a monthly basis, or
    2. in the case of a sewage treatment plant with a seasonal discharge, on the frequency specified in the approval;
  2. conduct an initial characterization of effluent using a manner specified by the Director within five years of the amendment; and
  3. report back to the Director within six months of the initial characterization of effluent being completed.

4.3-DP - No new municipal sewage treatment plant shall be established in the Lake Simcoe watershed unless,

  1. the new plant is intended to replace an existing municipal sewage treatment plant, or
  2. the new sewage treatment plant will provide sewage services to,
    1. a development that is on partial services; or,
    2. a development where one or more subsurface sewage works or on-site sewage systems are failing.

4.4-DP - No new non-municipal sewage treatment plant shall be established in the Lake Simcoe watershed unless the person applying to establish the plant can demonstrate that:

  1. the plant will result in a net reduction of phosphorus loadings to the watershed from the baseline conditions for the property that would be serviced by the new plant; or
  2. the undertaking that the plant will serve will not add phosphorus loadings to the Lake Simcoe watershed.

The Strategy builds on these policies by establishing strict phosphorus effluent limits and loading caps on the municipal and private STPs. An aggregate “baseline load” from the STPs of 7.2 T/yr has been established. The baseline load, described in Table 2 below, would be applied to each STP at its next expansion or by 2015, whichever occurs first. It is important to note that these baseline loads were calculated using the currently approved rated capacity for each STP, which accommodates some of the projected growth to 2031 as per the Growth Plan for the Greater Golden Horseshoe. This is why six of the facilities show an increase in baseline phosphorus loads when compared to the Interim Regulation loads. Appendix A contains more detailed information on how these effluent limits and loads were determined and the estimated costs for each plant to achieve its baseline limit by 2015. The individual loads were based on the categorization of the STPs into tiers based on current Certificate of Approval loads and calculated using the approved rated capacity for each STP. Although the baseline load is higher than the current load being discharged from the STPs, it is slightly lower than the load under the Interim Regulation. Since each STP would be required to meet its loading cap by 2015, or by the next time it expands (whichever occurs first), this would allow for a period of “stabilization” giving municipal and private owners a reasonable length of time to plan any required upgrades or expansions. The Ministry has also consulted on an amendment to the Lake Simcoe Protection Plan which requires that these baseline loading caps be incorporated into the Certificate of Approval for each STP.

Phosphorus Reduction Strategy Strategic Direction #2

The baseline effluent limits and loads will be adopted as objectives, which will require municipalities to use best efforts to meet them. The limits and loads will become compliance limits in each STP's Certificate of Approval (issued by the Ministry of the Environment) by 2015 or the next time an STP expands, whichever occurs first.

“Objectives” and “compliance limits” are regulatory terms used to describe effluent concentrations and loads for STPs that appear in sewage works Certificates of Approval. Objectives are the concentrations and loads an STP is designed to meet under ideal operating conditions, while compliance limits are slightly higher to allow operational flexibility and are enforceable. By adopting the baseline effluent limits and loads as objectives in a Certificate of Approval, we are asking STP operators to use best efforts to meet them. These baseline limits are either lower or the same as the compliance limits currently in their Certificates of Approval.

The STPs are required to report their effluent concentrations and loads either monthly or seasonally (i.e. lagoons). This provides the Ministry with a regular update of how each plant is operating and would trigger a compliance response if an STP’s phosphorus discharge exceeds its compliance limit.

Table 2: Baseline Phosphorus loads for STPs (kg/yr)
Sewage Treatment PlantCurrent CofA Load Limit (kg/yr P)Baseline Compliance Loading (kg/yr P) To be achieved by 2015 or the next expansion
Uxbridge Brook WPCP285286
Beaver River # 1 WPCP (Sunderland)6958
Lake Simcoe (Beaverton) WPCP190190
Beaver River # 2 WPCP (Cannington)11797
Schomberg WPCP7575
Sutton WPCP224187
Keswick WPCPfootnote 1655655/876
Mount Albert WPCP7575
Queensville / Holland Landing Lagoon WPCP149124
Barrie WPCC49932,774
Bradford WPCP747698
Innisfil WPCP803629
Orillia WTCC2993996
Lagoon City STP249124
Silani Cheese STP2227
Total11,6466,995/7,216

Note: These baselines loads will be objectives between March 31, 2010 and 2015 or until the next time a plant expands, whichever occurs first, unless they are already requirements on a C of A. (1000 kilograms = 1 metric tonne)

Longer-Term Actions

To ensure that the STP contribution of phosphorus meets the whole-lake phosphorus-loading goal for Lake Simcoe of 44 T/yr, their total load must be reduced to 7 % of 44 T/yr, which works out to 3.2 T/yr.

Existing research suggests that relying on today’s technology alone to reduce the STPs’ contribution to the Lake Simcoe phosphorus problem will be costly. In addition, current projections indicate that even incorporating all of the technology that is currently available would not enable the plants to meet their targeted load for 2045.

At this time, it is not practical to require the STPs to reduce their loads below the baseline limits. The requirement for further incremental reductions will be re-evaluated in 2015 during the first review of the Strategy.

Other considerations:

In addition to limiting the phosphorus loads being discharged from the STPs, there are other actions that can be taken to reduce the phosphorus load from STPs. Some of these include:

  • Reducing bypasses
    • STP bypasses (the discharge of either untreated or partially treated sewage during wet weather or mechanical failure) can contribute additional phosphorus load and is not typically accounted for in assessing annual loads. While the bypass quantity is usually measured and reported, the quality is not.
    • In order to comply with the established load caps, STP owners and operators will need to consider the additional loads from bypass events.
    • In addition, best efforts should be used to reduce or eliminate bypasses wherever possible.
    • As new emerging treatment technologies are assessed, their effectiveness in avoiding bypasses would need to be considered. These systems are typically not as robust as conventional secondary and tertiary treatment systems and would need to demonstrate their ability to handle wet weather flows.
  • Biosolids management:
    • Using best management practices during land application of biosolids can mitigate the amount of phosphorus that is washed off to a lake or its tributaries. Examples of BMPs include; surface versus injection applications; buffer zones between application areas and watercourses; mixing biosolids with soil at application to reduce the risk of runoff; and timing of application after rain events.
    • Biosolids can also be managed through incineration, which is currently being done by some watershed municipalities.
  • Water conservation:
    • Water conservation can play an important role by reducing the amount of sewage that needs to be treated, making the treatment process more efficient and can potentially delay the need to expand an STP.
    • Sewage volumes can be reduced by implementing water conservation measures and taking action to reduce inflow and infiltration into the sewer system.
  • Innovative technologies, such as water re-use treating wastewater effluent discharged from STPs include:
    • “purple pipe” systems in new homes, businesses, industry and public facilities to re-use treated effluent to flush toilets and water lawns (non-potable water);
    • irrigation of golf courses, sod farms and lawns; and,
    • maintaining environmental flows in watercourses

Urban Runoff And Stormwater

Urban stormwater makes a substantial contribution to the total phosphorus load to Lake Simcoe at approximately 31% by current estimates. As the urban area is intensified and expanded to accommodate population and employment growth in the watershed, the phosphorus load from urban development is expected to increase. There is also a significant opportunity to reduce the phosphorus contribution from this source.

Current Load

Urban stormwater runoff from rain and melting snow washes pavement and other hard surfaces of contaminants and debris - and these materials either go directly into Lake Simcoe or its inflowing rivers and streams. Urban stormwater runoff contains phosphorus from fertilizers that are used on lawns and in gardens and parks, from pet and wild animal waste, from detergents (e.g., car washing) and from soil (naturally occurring). Urban stormwater runoff can increase the temperature of the transported water and also contribute metals, hydrocarbons, bacteria and other harmful contaminants to the Lake and its watershed, impacting water quality.

Urban non-point sources of phosphorus are much higher than the natural background levels for the watershed. Scientists estimate that the annual phosphorus load going into the Lake was about 32 T/yr during the 1800s, before the major settlement that took place in the area. Urban development takes up only 6% of the total watershed area. Deducting the phosphorus contributed through atmospheric sources (9 T/yr), the estimated background load from 6% of the watershed would have been approximately 1.4 T/yr.

The phosphorus load from the urban areas in the Lake Simcoe watershed is currently estimated at about 23 T/yr, or about 31% of the total phosphorus load. This load is approximately 22 T/yr above the natural background level of phosphorus. This estimate is based on analysis by the LSRCA, and is summarized in the report Lake Simcoe Basin Stormwater Management and Retrofit Opportunities, 2007.

Early Actions

Before the 1990s, it was common practice in areas of urban development to route stormwater into storm drains that took the water directly to Lake Simcoe or its tributaries. However, over the last two decades efforts have been made to intercept and treat stormwater. Urban areas that have stormwater quality control facilities (such as stormwater ponds) capture pollutant-laden suspended solids, including phosphorus from storm runoff. This has resulted in less phosphorus entering Lake Simcoe and its tributaries. Since 1994, the Ministry of Environment’s sewage works approval program requires the construction of stormwater management control facilities to service all new urban development to help reduce water quality and quantity impacts from urban runoff. Since 1996, the LSRCA has required “Enhanced” or “Level 1” treatment for all new urban development in the Lake Simcoe watershed. There are a number of methods currently used to control urban stormwater runoff. In general, the most common method involves the creation of ponds that intercept and provide natural water quality treatment through sediment deposition. Some newer methods reduce the amount of runoff by using on-site, landscape solutions and even rainwater harvesting systems which intercept, convey and store rainwater for future use. These innovations can often be applied to existing urban areas as well as new developments and offer an opportunity to control urban runoff in places where conventional methods may not be practical.

Enhanced treatment is designed to remove 80% of suspended solids and should be used in areas of sensitive aquatic habitat.

Other measures with long term implications include stewardship, education and outreach activities. These actions are included as part of several stewardship-related policies in the Plan, and through the development of a Community Stewardship Program, will contribute to an increased awareness of phosphorus sources and encourage rural and urban residents and land managers to protect natural features and engage in activities and behavioural changes that can further reduce phosphorus inputs into urban and rural stormwater.

Related Policies

The Lake Simcoe Protection Plan already contains a number of specific policies designed to reduce and control the amount of phosphorus that enters the watershed from urban stormwater. However, this Strategy provides additional actions to fill gaps that have been identified, and to utilize opportunities that may be present. These policies have guided the recommendations in this section, and are listed below:

4.5-SA - Within five years of the date the Plan comes into effect, municipalities, in collaboration with the LSRCA, will prepare and implement comprehensive stormwater management master plans for each settlement area in the Lake Simcoe watershed. The stormwater management master plans will be prepared in accordance with the Municipal Class Environmental Assessment…

4.6-SA - Municipalities are encouraged to implement a stormwater retrofit prior to the completion of a stormwater management master plan if a stormwater retrofit opportunity has been identified as a priority for a settlement area and is determined to be economically feasible.

4.7-DP - Municipalities shall incorporate into their official plans policies related to reducing stormwater runoff volume and pollutant loadings from major development and existing settlement areas…

4.8-DP - An application for major development shall be accompanied by a stormwater management plan…

4.9-DP - Stormwater management works that are established to serve new major development in the Lake Simcoe watershed shall not be permitted unless the works have been designed to satisfy the Enhanced Protection level specified in Chapter 3 of the MOE's “Stormwater Management Planning and Design Manual 2003”, as amended from time to time.

4.10-DP - Every owner and operator of a new stormwater management works in the Lake Simcoe watershed shall be required to inspect and maintain the works on a periodic basis.

4.11-DP - Every owner and operator of a new priority stormwater management works in the Lake Simcoe watershed shall be required to monitor the operation of works, including monitoring the quality of the effluent from the works, on a periodic basis.

4.12-SA - The MOE will review the approvals issued under section 53 of the Ontario Water Resources Act in respect of existing priority stormwater management works within the Lake Simcoe watershed.

4.17-SA - Within three years of the date the Plan comes into effect, the MOE will:

  1. review measures…to reduce water quality impairment, including the contribution of phosphorus loadings to the Lake Simcoe watershed from construction activities;
  2. evaluate the effectiveness of the measures;
  3. identify preferred measures based on the review and the study referred to in policy 4.17, including the types of policies that could be included in the Plan.

4.20-DP - Municipalities shall ensure that the following measures are incorporated into subdivision agreements and site plan agreements:

  1. keep the removal of vegetation, grading and soil compaction to the minimum necessary to carry out development activity;
  2. removal of vegetation shall not occur more than 30 days prior to grading or construction;
  3. put in place structures to control and convey runoff;
  4. minimize sediment that is eroded offsite during construction;
  5. seed exposed soils once construction is complete and seasonal conditions permit; and,
  6. ensure erosion and sediment controls are implemented effectively.

For further details on these policies, please see the Lake Simcoe Protection Plan.

More Must Be Done…

Stormwater Retrofits for Existing Development

The reduction of phosphorus loads from existing urban areas will be achieved by retrofitting existing stormwater facilities and by putting in facilities in currently uncontrolled areas, where feasible. Studies undertaken by the LSRCA identified approximately 160 retrofit opportunities that would result in a phosphorus reduction of approximately 4.2 T/yr at an estimated cost of about $63 million. It is estimated that a significant number of these projects could be completed within the next 5-7 years.

Low Impact Development – An Opportunity to Reduce Further

Low Impact Development (LID) refers to practices that mimic the natural flow and behaviour of water as it runs off developed areas (as compared to traditional practices which move the water off the site as quickly as possible). LID reduces the total area of impervious surfaces and promotes water retention on- site to enhance the percolation of water through the soil.

LID practices also help lower the water temperature and reduce the volume of runoff that enters stormwater management facilities and the Lake. Preliminary research indicates that up to 2.7 T/yr of phosphorus from existing urban areas could be removed through the use of LID practices. The LSRCA is currently conducting a study on the cost of Low Impact Development opportunities to be completed in the Summer of 2010. This will help to inform municipalities, developers and others on the relative costs and merits of LID practices to help achieve reductions in phosphorus loadings.

Examples of LID practices include:

  • Green rooftops
  • Permeable pavement
  • Infiltration trenches
  • Bio-retention gardens
  • Rainwater harvesting - intercepting, diverting and storing rainfall for future use
  • Soakaway pits - stone-filled trenches that temporarily store water to be infiltrated

New Development

Environmentally sustainable development is one of the key objectives of the Lake Simcoe Protection Plan. Accordingly, the future economic and population growth in the Lake Simcoe watershed must be managed in a way that sustains a healthy ecosystem, a healthy economy and healthy communities. The Lake Simcoe Protection Plan provides direction to accommodate the implementation of the Growth Plan for the Greater Golden Horseshoe. The Growth Plan provides population and employment forecasts and policies for municipalities to plan for forecasted growth.

Moving to no net phosphorus from new development will promote sustainable development while continuing to reduce the impact of phosphorus on Lake Simcoe. This strategic direction could require that before proposals for major developments are approved outside of built-up areas as defined under the Growth Plan, those responsible for the proposal demonstrate how the development will meet the requirement of moving to no net increase in phosphorus loading. This strategic direction could be enshrined in the Plan through an amendment to Policy 4.8-DP that now requires major development applications to be accompanied by stormwater management plans. New developments could be required to comply with specific requirements that would have to be met before the developments could proceed, including requiring that specified BMPs be followed during the construction phase. Guidance documents will be developed in consultation with municipalities, the development industry, other provincial ministries, and other watershed partners to provide direction on the information required (i.e. Phosphorus budgets) to demonstrate how the intent of moving to no net increase in phosphorus is to be met. This strategic direction would come into effect once guiding documents are finalized. Any proposal to amend the Plan to enshrine the strategic direction of moving to no net phosphorus from new development in the watershed would be subject to further consultation.

Phosphorus Reduction Strategy Strategic Direction #3

Move to no net increase in phosphorus loading from new development.

In order to prepare preliminary estimates of potential loading of phosphorus from stormwater due to new development, a projection of the total area of new development within the watershed was undertaken. This estimate was based on adopted and draft official plans prepared by the municipalities in the watershed. To determine the area of new development in designated greenfield areas, the total amount of existing built-up areas was subtracted from the estimate of land designated and projected to accommodate population and employment growth. Since the conformity process to the Growth Plan for the Greater Golden Horseshoe is still ongoing, the information used to calculate this preliminary estimate was obtained from various sources, including mapping layers used in the Lake Simcoe Assimilative Capacity Study (2006), estimates of existing developed areas by the LSRCA, as well as potential settlement area expansion scenarios.

For the purposes of the Strategy, a maximum amount of land to be developed was assumed. The amount of land assumed was for analysis purposes only and is subject to change as the basis of these estimates are draft and adopted official plans that are not yet in effect and are subject to Growth Plan conformity. On this basis, the preliminary estimate of the total area within the watershed where new development might occur to 2031 is approximately 17,000 hectares.

As described earlier, under the Plan all new developments are required to have “Enhanced” stormwater management controls in place, subject to limited exceptions. Accounting for these controls, analysis indicates the phosphorus load from these new developments would be 15.3 T/yr. Additional analysis indicates that combining “Enhanced” stormwater management controls with LID practices would reduce the phosphorus load from new development to 9.2 T/yr.

While the Strategy and the Plan strongly encourage that effective measures are taken to mitigate and reduce phosphorus contributions from new development wherever possible, significant phosphorus loadings from development will occur and should be offset in some way. This is the reason the Strategy is recommending a strategic direction of move to no net phosphorus from new development as discussed above. It is recognized that in developing and implementing this strategic direction, important issues have to be resolved; for example, a method for determining no net additional phosphorus loads needs to be clearly established.

The Ministry is conducting a policy review of municipal stormwater management. While the review has not yet concluded, the preliminary indication is that best management practices need to be strengthened. One example is by updating the 2003 Stormwater Management Planning and Design Manual. As such, it is anticipated that the Ministry will be reviewing the existing guidance for the design, operation and maintenance of stormwater management facilities, including oil grit separators, to ensure stronger water quality protection and phosphorus reduction. The Ministry will engage municipalities, conservation authorities, developers and industry on the development of clear guidelines for oil grit separators, various infiltration systems and other new technologies.

Innovation and the implementation of new technology will also be important to reducing and removing the phosphorus load from urban sources over time. Therefore, it is critical to support innovation and to eliminate any barriers to implementing new approaches to potential reductions.

Tools that could be used for phosphorus reduction are provided in Table 3, and further details on stormwater management are provided in Appendix B.

Table 3: Phosphorus Reduction Tools
Phosphorus Reduction ToolsNew Urban DevelopmentExisting Urban Development
Install an Enhanced Level Protection for new Stormwater Management (SWM)Required for all new sitesStrive for SWM controls that will improve water quality and reduce P loading
Retrofit existing stormwater management facilities Primary SWM tool for P eduction in the watershed for existing urban sites
Municipal options, e.g. Cash-In-Lieu (C-I-L) offsetting programProvide C-I-L to offset net additional P loading for new urban sitesInstalled retrofits could generate credits/incentives from C-I-L program
Explore the potential for treating stormwater before it is released into the watershed from new and existing developments (e.g. on-site stormwater retention)Good design practice where possibleGood design practice where possible
Improve clean-out frequency of catchbasin sumps and SWM oil/grit separators (i.e. annually or every two years as required by the manufacturer - some municipalities contract this out and require a report and do random inspections based on the report)Good maintenance practiceGood maintenance practice
Implement innovative technologies and approaches, (i.e. LIDs approaches and water re-use)Good design practiceGood design practice
Oil-grit separators in stormwater treatment systemsGood design practiceGood design practice

Suggested actions that can be taken by individual homeowners in new and existing urban areas:

  • Eliminate or reduce the use of phosphorus-rich lawn fertilizers. Consider slow release phosphorus fertilizers that maximize plant uptake of available phosphorus, or do not use fertilizer;
  • Promote the choice for natural meadow field lawns for homeowners. These lawns require little or no fertilizer and/or reduced lawn cutting frequency;
  • Use rain barrels to harvest rainwater for watering lawns;

Rural And Agricultural Sources Of Phosphorus

Current Load

The 2006 Assimilative Capacity Study completed through the IGAP estimated that the current phosphorus load from hay, pasture and cropland is 17 T/yr, which represents approximately 25% of the total phosphorus load. Some agricultural lands in the Lake Simcoe watershed accommodate additional phosphorus generated by the STPs through the application of biosolids (treated sewage sludge from STPs) as a useful nutrient addition to grow certain types of crops (e.g. hay).

Agriculture currently accounts for 47% of the total watershed area. Deducting the phosphorus contributed through atmospheric sources (9 T/yr), the estimated background load from 47% of the watershed would have been approximately 11 T/yr. Adding the current contribution of 3 T/yr from the Holland Marsh and smaller polders (discussed in the following section) to the current phosphorus load from hay, pasture and cropland of 17 T/yr, the current load from agriculture is 20 T/yr or 9 T/yr above the natural background level of phosphorus. It is important to note that agriculture also makes up a component of the atmospheric contribution of phosphorus.

Phosphorus reduction from agriculture and rural sources

Modelled projections estimate that 5 T/yr of phosphorus could be reduced from agriculture and rural loads to tributaries through participation in stewardship programs. An additional 2 T/yr is projected to come from the conversion of agricultural lands to urban uses to accommodate approved growth for a total reduction of 7 T/yr.

Early Actions

Voluntary participation in agricultural and rural stewardship programs has a long history of success in the Lake Simcoe watershed. Long-running programs such as the LSRCA's Landowner Environmental Assistance Program (LEAP) and the Canada-Ontario Environmental Farm Plan’s suite of programs (EFP) are successful because they combine education with incentives to adopt Best Management Practices (BMPs), resulting in changes in land management that provide sustained environmental benefits over time. There is a need for continued support for phosphorus reduction activities, and for those activities to be identified in the grower’s EFPs in order to ensure that priority is also given to actions specific to phosphorus reduction.

The EFP suite of programs has been running since the early 1990s. Under the Agricultural Policy Framework in the Lake Simcoe Watershed (2005 – 2008), approximately 1,100 farmers participated in an EFP workshop. Approximately $4.6 million was invested in almost 300 on-farm projects.

Since the Lake Simcoe Farm Stewardship Program’s inception, 200 new on-farm projects have been completed, for a provincial investment of $1.4 million. These projects also used federal EFP cost-share funding and farmers’ own contributions (a program requirement).

These programs have helped the agricultural sector make a significant contribution to reducing phosphorus loading from agricultural and rural sources. For example, the LSRCA's LEAP program, running for 20 years, has contributed to an estimated reduction of 18 metric tonnes of phosphorus entering the Lake.

A few examples of practices that help to reduce phosphorus loads include:

  • Fertilizer, manure and other nutrient management techniques through appropriate storage and land application methods;
  • Buffers in riparian areas and along stream banks;
  • Shelterbelt/native vegetation establishment;
  • Improved cropping systems;
  • Water supply management;
  • Runoff control;
  • Erosion control structures and cover crops; and,
  • Balance livestock feed to maximize efficient use of phosphorus.

Sewage Biosolids and Septage

The addition of nutrients (phosphorus, nitrogen, potassium) on agricultural land through the application of sewage biosolids or other organic materials represents the completion of the nutrient cycle, whereby essential nutrients are returned to the soil to help foster new plant growth. The addition of organic matter also improves soil structure and its ability to hold water, which can decrease water runoff and soil erosion and increase overall water conservation.

Septage, the informal term for hauled sewage, classifies all matter that is pumped out of septic systems, holding tanks and portable toilets. Septage must not be confused with sewage biosolids, which refers to the residue from sewage treatment plants following treatment of sewage and removal of effluent.

Sewage biosolids and treated septage intended for land application must be treated by an approved process and must be tested prior to any application to determine nutrient content and to ensure they meet provincial quality standards. The land application site and receiving soils also must meet specified requirements and quality standards. Some examples of best management practices that can be used during the application of biosolids include: surface versus injection applications; buffer zones between application areas and watercourses, mixing biosolids with soil at application to reduce the risk of runoff; and timing of application after rain events.

Sewage biosolids and treated septage applied to agricultural lands are used, where approved, as a fertilizer replacement. In other words, these materials applied to agricultural lands as a nutrient will replace an equivalent amount of fertilizer, so are ‘phosphorus neutral’, and do not cause additional phosphorus to be applied within the watershed.

Related Policies

Policies 8.5-SA through 8.11-SA in the Plan (listed below) provide a number of policies to reduce phosphorus loading from rural and agricultural sources. These policies also apply to phosphorus reduction from agricultural polders, such as the Holland Marsh, and to the development and implementation of stewardship and community involvement programs that support the reduction of phosphorus loading throughout the watershed.

8.5-SA - Within one year of the date the Plan comes into effect, the MNR and other ministries, in collaboration with the First Nations and Métis communities, municipalities, the LSRCA, and other stewardship partners, will establish a broad-based, watershed-wide stewardship network. The network will strengthen the strategic focus of stewardship programs and activities and enhance collaboration among landowners, agencies, industry, and citizen/community organizations to support implementation of the Plan.

8.6-SA - The MNR and the MAFRA, in collaboration with municipalities, the LSRCA, the First Nations and Métis communities, and other stewardship partners, will develop a structured educational and incentive-based stewardship program for rural and urban (non-farm) landowners in the watershed to promote the adoption of best management practices that support implementation of the Plan.

8.7-SA - The MAFRA, in consultation with the MNR, the LSRCA and agricultural organizations, will continue to develop and implement broad-based agri-environmental stewardship programs to promote the adoption of best management practices to support Plan priorities, including phosphorus load reduction, and riparian, soil and water management.

8.8-SA - The MAFRA, in consultation with the MNR, the LSRCA and other agricultural organizations, will promote the development and implementation of best management practices demonstration and pilot projects focused on innovation and technology advancement as a means of supporting agricultural stewardship activities.

8.9-SA - Within three years of the date the Plan takes effect, and based on the results of other agri-environmental stewardship initiatives and scientific work completed in the watershed, the MAFRA and its stewardship partners will reassess stewardship programming, and modify as necessary, to address priority needs in the watershed.

8.10-SA - Based on the findings of the study identified in policy 4.16, 4.17, the MAFRA and its stewardship partners, in consultation with key stakeholders, will determine the need for additional or modified stewardship and best management practice measures to reduce phosphorus loadings and wind-borne erosion from agricultural activities in the Lake Simcoe watershed.

8.11-SA - The MOE, in consultation with industries, businesses, the development community, municipalities and other community organizations, will review operational, building and development standards and best management practices. Innovative design elements, for example, site-level storm water controls such as rain barrels or permeable pavements, and other site-specific options for stewardship will be encouraged.

We need to do more…

This Strategy encourages holistic, integrated stewardship approaches to enable neighbours (including farmers and non-farmers) to partner on some projects to increase the effectiveness of their combined actions. This approach will enhance opportunities for innovative developments in this sector (e.g., technological advancement in the agricultural sector, rural economic development) along with the integration of urban stewardship activities. Stewardship and the implementation of BMPs appear to be cost-effective ways to reduce phosphorus. Research is underway to assess the effectiveness and monitor the progress of stewardship activities.

The Strategy also encourages continued research and monitoring activities to increase the focus on priorities such as seasonal impacts (particularly runoff from melting snow), landscape approaches (e.g., differences between subwatersheds) and the effectiveness of BMPs. Stewardship programs will be assessed as new information becomes available so that the programs can be adapted and improved as needed.

Phosphorus Reduction Strategy Strategic Direction #4

The Phosphorus Reduction Strategy encourages continued best management practices through stewardship activities to continue to reduce the phosphorus load from rural and agricultural sources. The Strategy will revisit strategic voluntary actions at the next Plan update.

Longer-Term Action

Experience in Ontario and elsewhere suggests that voluntary stewardship programs are generally a cost-effective way to address a number of environmental issues from non-point sources of phosphorus, including impaired water quality.

Under the Strategy, the ongoing results of research and voluntary stewardship programs will be used to assess and adapt the types of practices encouraged and supported over time.

The Holland Marsh and Smaller Polders

The Holland Marsh is an area of 27 square kilometres near Bradford West Gwillimbury and is the largest of four polders that have been dyked and drained for the purpose of growing vegetables. The three other polders include the Keswick, Colbar and Bradford Marshes.

Current Load

The current phosphorus load from polders including the Holland Marsh and several smaller polders within the Lake Simcoe watershed, is estimated to average 3 T/yr, based on monitoring conducted by the LSRCA and MOE between 2002 and 2007. This represents about 4 % of the total phosphorus load in the watershed.

Early Actions

A number of BMPs to reduce the phosphorus load from polders are currently being implemented through existing agricultural stewardship programming. Examples of these BMPs include:

  • Companion cropping to reduce wind erosion
  • Bank stabilization
  • Irrigation and Nutrient Management

Due to the unique nature of organic soils and the wide variety of high-value crops that are grown in the Lake Simcoe area polders, further research is needed to determine a more appropriate set of tools and actions to address phosphorus loading from this sector. This research will focus on the development of new BMPs specifically for polder agriculture — including both on-farm opportunities and the potential for treating pump-off water before it is discharged to the watershed. For example, using Phoslock™ to treat pump-off water from polders before it is discharged into the Lake could be a cost-effective way to reduce the phosphorus contribution from polders until longer-term BMPs can be developed and implemented (See Section 7 for more information on Phoslock™).

Phosphorus Reduction Strategy Strategic Direction #5

Enhance existing stewardship programs to reduce the total phosphorus load from polders by an estimated 1 T/yr between 2013 and 2032, and promote research and innovation to determine if additional reductions are possible.

Related Policies

The policies in the Plan that support phosphorus load reduction from agricultural polders are identical to those listed for runoff from agricultural and rural areas (See policies 8.5-SA through 8.11-SA).

Additional Considerations

The Holland Marsh and other polders in the Lake Simcoe watershed are the major source of fresh vegetables for the Greater Toronto Area (GTA) and a significant source of agricultural exports for Canada. As a result, the potential impacts on the costs and benefits of local food production need to be considered when assessing the phosphorus reduction research work that is currently under way.

Links with Other Policies

The Lake Simcoe area’s polders represent a complex drainage area that falls under the overall jurisdiction of the Drainage Act. Currently, a canal reconstruction project is under way. This project represents a potential opportunity to implement innovative solutions to bank stabilization and drainage issues.

On-Site Sewage Systems Within 100 Metres of Lake Simcoe

Current Load

The current phosphorus load from the residential and industrial on-site sewage systems (or septic systems) located within 100 metres of Lake Simcoe is estimated at 4.4 T/yr. This represents about 6 percent of the total phosphorus load to the Lake. The contribution from systems beyond 100 meters of Lake Simcoe is included in the phosphorus load that is measured through monitoring of the tributaries that feed into the Lake. While further study of these systems and their contribution is needed, a number of studies completed in other areas suggest that phosphorus from such systems could migrate through the soil and contribute to the total load in the Lake.

Related Policies

The Lake Simcoe Protection Plan contains several policies dealing with on-site sewage systems that are intended to have significant water quality benefits - for example, by reducing waterborne pathogens (see policies listed below).

The Plan also commits the Province to develop a draft shoreline protection regulation within one year that would designate lands within 100 metres of the Lake Simcoe shoreline to require septic system re-inspections. See 4.13-SA in the section below.

The Province is fulfilling this commitment by releasing a proposed draft regulation for comment. The draft regulation proposes to reduce phosphorus by protecting the shorelines of the watershed through restrictions on specified activities, including the removal of vegetation, application of fertilizers, requiring setbacks on septic systems and offering enhanced protection of wetlands.

4.13-SA - Within one year of the date the plan comes into effect, the MAH and the MOE will develop a proposal for a regulation under the Ontario Building Code Act, 1992, to designate the lands within 100 metres of the Lake Simcoe shoreline, other lakes in Lake Simcoe watershed, and any permanent stream of Lake Simcoe as a prescribed area for required on-site sewage system maintenance re-inspections.

4.14-SA - The MAH, in consultation with the MOE, municipalities, conservation authorities, health units and industry partners, will consider new standards, including those being developed by the Bureau de Normalisation du Québec for small on-site sewage systems that evaluate new treatment unit technologies with respect to the reduction of pathogens and nutrients. The MAH will consider the appropriateness of an amendment to Ontario’s Building Code to incorporate the new standards.

4.15-DP - Subject to other policies of the Plan, a new on-site sewage system or subsurface sewage works shall not be permitted within 100 metres of the Lake Simcoe shoreline, other lakes in Lake Simcoe watershed, or any permanent stream except in the following circumstances:

  1. a proposal for an on-site sewage system or subsurface sewage works that would serve an agricultural use, an agricultural-related use or a public open space;
  2. a proposal for an on-site sewage system or subsurface sewage works that would replace or expand the capacity of an existing on-site sewage system or subsurface sewage works that will serve a use that would have been permitted by the applicable zoning by-law, as of the effective date of the Plan; or
  3. a proposal for an on-site sewage system or subsurface sewage works that relates to a development proposal for only one dwelling, where the proposal would have been permitted by the applicable zoning by-law as of the effective date of the Plan.

Links with other Policies

Currently, some municipalities in the Lake Simcoe watershed are requiring landowners who own failing on-site sewage systems to hook up to the municipal sewage treatment system. Moreover, replacing or repairing failing on-site sewage systems, or restricting the construction of new shoreline on-site sewage systems and encouraging owners of failing systems to hook up to municipal sewage treatment systems will contribute to improving near-shore water quality by reducing the pathogens entering the watershed. These measures may also help to reduce the total phosphorus load from on-site sewage systems.

Longer-Term Actions

On going research into phosphorus migration in soil should help to determine the extent to which other on-site sewage systems in the watershed (i.e., those located more than 100 m from the shoreline) contribute to total phosphorus loading. It could also lead to the development of phosphorus removal technology for septics in the long term.

Stewardship initiatives, such as using phosphorus free products, could also reduce phosphorus inputs to on-site sewage systems and as a result could have a direct and beneficial impact on water quality. These actions will be incorporated into the broader stewardship strategy in order to encourage watershed residents to adopt more environmentally friendly practices in and around their homes and cottages.

Atomspheric Deposition of Phosphorus

Current Load

The current phosphorus load from atmospheric sources to Lake Simcoe is estimated to be 19 T/yr — or about 27 % of the total phosphorus load. Using a background atmospheric loading rate of 12 kg/km2footnote 2, the loading to the Lake from the atmosphere would have been 9 T/yr prior to major settlement in the Lake Simcoe watershed and surrounding areas. Thus the current atmospheric phosphorus load to the Lake is about 10 T/yr above the natural background level.

Atmospheric phosphorus comes from natural sources such as pollen, the burning of fossil fuels, and wind transport of disturbed soils. Some examples of disturbed soils include:

  • land that is stripped of plants during construction;
  • aggregate operations;
  • unpaved roads; and,
  • agricultural fields before crops are planted.

Some of the phosphorus transported this way is deposited directly into Lake Simcoe. While research is currently under way on this major source of phosphorus loading, the early results indicate that sources of dust both from within and outside of the watershed are important contributors of phosphorus.

Early Actions

Continuing and enhancing existing voluntary agricultural stewardship programs could reduce the total phosphorus load from atmospheric sources between 2013 and 2032 to 15 T/yr. The Plan requires that measures to minimize soil erosion be included in subdivision and site plan agreements.

Research Initiatives

Research is currently underway to learn more about the sources of phosphorus deposited by the atmosphere into Lake Simcoe. The University of Guelph is working on a comprehensive research project to:

  • More accurately calculate the spatial distribution of rainfall and atmospheric deposition of phosphorus over Lake Simcoe using RADAR data;
  • Quantify the contribution of key local sources of dust emission including construction sites, quarry operations and agricultural fields using field tests and modelling; and,
  • Identify the most effective opportunities to reduce atmospheric deposition loads using modelling for a range of best management practices.

Related Policies

Several policies in the Plan will lead to a better understanding of the sources of atmospheric phosphorus and promote the implementation of BMPs to reduce soil erosion and atmospheric deposition. These include:

4.16-SA - Within two years of the date the Plan comes into effect, the MOE will complete a study that identifies the sources of atmospheric deposition contributing phosphorus to the Lake Simcoe watershed.

4.17-SA - Within three years of the date the Plan comes into effect, the MOE will:

  1. review measures, including regulatory controls and best management practices, to reduce water quality impairment, including the contribution of phosphorus loadings to the Lake Simcoe watershed from construction activities;
  2. evaluate the effectiveness of the measures; and
  3. identify preferred measures based on the review and the study referred to in policy 4.17, including the types of policies that could be included in the Plan.

4.18-SA - Within three years of the date the Plan comes into effect, the MNR and the MOE, in consultation with the aggregate industry and key stakeholders, will determine the need for additional standards in the Aggregate Resources of Ontario-Provincial Standards for mineral resource aggregate activities within the Lake Simcoe watershed. The determination will be based on the findings of the study identified in policy 4.17 and the MNR's review of the Aggregates Resources of Ontario-Provincial Standards.

4.19-SA - The mineral aggregate resources industry is encouraged to adopt best management practices as a proactive measure to reduce potential contribution of phosphorus loadings to the Lake Simcoe watershed.

4.20-DP - Municipalities shall ensure that the following measures are incorporated into subdivision agreements and site plan agreements:

  1. keep the removal of vegetation, grading and soil compaction to the minimum necessary to carry out development activity;
  2. removal of vegetation shall not occur more than 30 days prior to grading or construction;
  3. put in place structures to control and convey runoff;
  4. minimize sediment that is eroded offsite during construction;
  5. seed exposed soils once construction is complete and seasonal conditions permit; and
  6. ensure erosion and sediment controls are implemented effectively.

4.21-HR - Site alteration in the Lake Simcoe watershed shall be undertaken in a manner that incorporates the measures set out in policy 4.20.

Additional Considerations

At this point, it is difficult to say how much controlling local sources of dust will reduce the load of phosphorus from the atmosphere. What is certain is that reducing airborne dust will improve air quality throughout the Lake Simcoe watershed. The results of the research, referenced above, will continue to inform the best way to move forward and reduce phosphorus from atmospheric deposition.

A number of best management practices exist for controlling the wind erosion and excessive dust that contribute to the phosphorus load from the atmosphere to Lake Simcoe. These practices include:

  • adopting and enforcing soil conservation by-laws;
  • preserving existing vegetation;
  • controlling the speed of traffic over unpaved roads.

In the agricultural sector, best practices include:

  • leaving the soil intact instead of turning it over (no-till techniques);
  • planting windbreaks;
  • leaving un-harvested plant material on fields; and,
  • using cover crops to hold the soil in place.

For more information on what you can do to help reduce phosphorus loading from atmospheric and other sources, please visit the Report on the Phosphorus Loads to Lake Simcoe website.

Longer-Term Actions

In order to meet the whole-lake goal for phosphorus loading of 44 T/yr, a further reduction of 3 T/yr in the contribution from atmospheric sources will be needed. This reduction is in addition to what has been identified in the agricultural stewardship actions described above, for a total 7 T/yr reduction in the annual load.

The Strategy supports the policies in the Plan by providing additional strategic direction to address sources of atmospheric phosphorus.

Phosphorus Reduction Strategy Strategic Direction #6:

To meet long term reductions in loadings from atmospheric deposition the following strategic actions are to be pursued:

  • Continue and expand the use of focused stewardship opportunities to implement best management practices that can help address both urban and agricultural sources of airborne phosphorus, through programs such as LEAP, Environmental Farm Plans and other proven stewardship initiatives.
  • Work with the aggregate and development industries to help identify partnership-based approaches to filling information gaps and building scientific knowledge and recommendations on best management practices.
  • Work with the aggregate and development industries to identify opportunities for phosphorus reduction, while examining ways to increase the use of best management practices.

Over the next five years, atmospheric phosphorus loading will be a major research priority as scientists work to identify the major sources of atmospheric phosphorus pollution in the Lake Simcoe watershed. This research will inform the development of effective control programs that go beyond the interim measure of implementing the best management practices outlined above. Using the adaptive management principle, future versions of the Strategy and amendments to the Plan may also include additional specific actions that need to be taken outside the Lake Simcoe watershed to address the sources of atmospheric phosphorus.

6. Monitoring And Compliance

Monitoring

Long term monitoring is a critical part of the overall effort to restore the health of Lake Simcoe. Monitoring is needed to measure the success of the phosphorus reduction actions, as well as progress towards achieving the target of 7 mg/L for dissolved oxygen. Within the Lake Simcoe watershed, the Ontario Ministries of the Environment and Natural Resources, as well as Environment Canada, Parks Canada and the LSRCA work together to operate regular monitoring programs. The Ministry of the Environment’s long term Lake Simcoe phosphorus monitoring network, for example, is operated in partnership with the LSRCA. The network currently includes the following elements and is shown in Figure 6:

  • 19 stations for year-round monitoring of inflowing rivers and outflow from lake;
  • six atmospheric deposition collectors for measuring the phosphorus deposited in rain, snow and dust;
  • two full meteorological stations for monitoring weather and precipitation events;
  • 10 in-lake stations and three stations in the mouth of the Holland River for collecting data during the ice-free seasons; and,
  • year-round analysis of untreated lake water collected from intake pipes at three municipal water treatment plants.

Figure 6: Lake Simcoe Monitoring Network

This map shows the locations of monitoring stations on and around Lake Simcoe in 2009. There are: 19 inflowing tributary and lake outflow monitoring stations, 6 atmospheric deposition collectors, 2 meteorological stations, 10 open lake monitoring stations, 3 monitoring stations in the mouth of the Holland River, and 3 municipal water treatment plant monitoring stations.

Compliance

The Strategy supports and builds on the requirements of the Lake Simcoe Protection Act, 2008 and the Lake Simcoe Protection Plan. The Strategy does this by providing a framework that will lead to proportional reductions in phosphorus loadings from all major sources within a realistic time frame. The Strategy also recognizes that numerous provincial ministries, agencies, the LSRCA and local municipalities already have strong legislative and regulatory frameworks in place to mitigate sources of phosphorus to the Lake. Some examples of applicable legislation are:

  • Environmental Protection Act (EPA);
  • Ontario Water Resources Act (OWRA);
  • Clean Water Act;
  • Planning Act;
  • Federal Fisheries Act;
  • Ontario Building Code ;
  • Conservation Authorities Act and Ontario Regulation 179/06 which deals with Regulation of Development, Interference with Wetlands and Alterations to Shorelines and Watercourses.

Achieving the phosphorus reduction targets throughout the watershed represents a significant challenge—one that requires all stakeholders to assume shared responsibility and be accountable for their actions. To achieve the Strategy’s objectives, compliance with the existing regulations and controls that are now in place will be critical. Moreover, actions to reduce phosphorus must become widespread and self-sustaining—in the same way that household recycling has become a widely practised part of waste management across Ontario.

7. Research, Modelling and Innovation

With the adaptive management approach underlying the Phosphorus Reduction Strategy, the Province anticipates that phosphorus reduction actions in the Lake Simcoe watershed will improve over time as the results of ongoing and future research help to enhance and refine the range and types of actions that are taken. To ensure this happens, ongoing collaborative research by the Province, the LSRCA, Environment Canada, and several universities and other partners will be a key component of developing and implementing the Strategy for the watershed. This work will build on past and current research and monitoring programs. It will also help to identify emerging issues in the watershed, while supporting the adaptive management approach adopted in the Plan.

The initial research and modelling work that relates to the Strategy focuses on the following areas:

  • The ongoing evaluation of the whole-lake phosphorus loading goal of 44 T/yr. This work is being undertaken by the Environmental Monitoring and Reporting Branch of MOE in partnership with York University and the LSRCA and will be an ongoing process as knowledge is gained and models are improved.
  • The development of subwatershed phosphorus loading targets. This work is being conducted in partnership with the LSRCA and is anticipated to be completed by the Ministry by summer of 2010.
  • The fine-tuning and improvement of existing lake water quality models that relate total phosphorus loads to dissolved oxygen levels. This work will also consider the value of using new models that have been applied to other aquatic ecosystems and research on invasive species, climate change and other emerging issues. This work is underway as part of an agreement between York University and MOE. In addition, a larger modeling project is being funded by the Federal Lake Simcoe Clean-Up Fund (LSCUF) led by York University, in partnership with MOE, the University of Waterloo, Queens University, the Ministry of Natural Resources and the LSRCA.
  • Studies of atmospheric pollution and its relation to phosphorus loading, including work that will help determine local atmospheric phosphorus sources and their relative contributions to the total phosphorus load in the watershed. This work will help to develop better estimates of the contribution atmospheric pollution makes to the total phosphorus load, using monitoring and modelling and an analysis of prevailing wind directions. The research and modelling will also help to prioritize phosphorus reduction efforts. Regional air modelling will also be undertaken to provide a better understanding of both long-range and local phosphorus transport. One study currently being undertaken is with the University of Guelph (in partnership with MOE and the LSRCA) with an anticipated completion date of 2011.
  • Ongoing studies on stormwater management, including the effectiveness and cost of various stormwater management designs, techniques and technologies.

By its nature, scientific research is conducted over the longer term, building on existing knowledge to increase what we know and help answer new questions. In addition to the projects described above, researchers are also studying internal phosphorus loading in Lake Simcoe. Internal loading refers to the load produced when phosphorus in the Lake that is bound to particles in sediments is re-suspended or dissolved.

The results of these and other research projects will be integrated into the Strategy as part of the adaptive management approach. Over time, new discoveries and knowledge will be used to ensure that phosphorus reduction programs and activities remain focused and effective.

Modelling

There are two main components of the modelling work being undertaken under the Strategy. One project will model the amount of phosphorus that can be expected to enter the Lake under future conditions. This model will be used to help develop subwatershed phosphorus loading targets. In the other major modelling studies, researchers will develop a detailed model of Lake Simcoe itself. Among other things, this model will help scientists learn more about the rate and direction of the water flow in the Lake.

Modelling and analysis will play a significant role in the adaptive management approach adopted by the Strategy. As more detailed or up-to-date information becomes available, models can be run again to ensure they represent Lake Simcoe and its watershed as accurately as possible. More details on the goals and anticipated results of the modelling work being undertaken through the Strategy are provided in Appendix D.

Innovation

Future development will increase the total area of impervious surfaces throughout the watershed. As a result, managing urban stormwater runoff will be one of the most important priorities in reducing phosphorus loading and maintaining or enhancing the local water balance. New technologies are continually being developed to control or treat stormwater runoff. Successful technologies have the potential to enhance management practices by effectively preventing pollution and environmental impacts related to stormwater runoff.

Research into innovative technologies and solutions will explore ways to prevent stormwater-related problems that relate to increased population growth and new development. This work will also help to provide answers about the best approaches to addressing problems in older urbanized areas where there are inadequate stormwater treatment measures in place.

Research over the next several years will focus on innovative technologies to:

  • prevent increases of phosphorus, nitrogen, sediment and chemical contaminant loads to Lake Simcoe from new development or re-development;
  • decrease the volume and velocity of stormwater, which will reduce phosphorus loading, flooding, stream bank erosion and habitat degradation; and,
  • demonstrate new and innovative approaches for managing storm water runoff (such as tree boxes, rain gardens, and green roofs) that can be applied by municipal governments and private property owners throughout the watershed.

In partnership with the Ontario Ministry of the Environment, the LSRCA is currently evaluating a number of promising phosphorus reduction technologies. Three of these innovative technology projects are described below.

Phoslock™

A pilot project is under way to test a phosphorus reduction product called Phoslock™. Announced in December 2007, the pilot study is investigating the effectiveness of Phoslock™ to determine its potential for use at sites throughout the Lake Simcoe watershed.

Phoslock™ is a material that is mixed with water, with the resulting slurry being applied to the surface of the water body. As the slurry moves down through the water, the Filterable Reactive Phosphorus (FRP) in the water is locked up inside the product. Once bound within Phoslock™ the FRP stays in place as a capping layer over the sediment, over a wide range of pH and salinity conditions, and at different water temperatures.

Field-testing is currently being conducted in the Lake Simcoe watershed.

Red Sand

Another pilot project currently under way is examining the potential of a red sand filtration chamber to remove phosphorus from urban stormwater runoff. As part of this project, native plants will be planted around the perimeter of a stormwater management pond, creating a natural shoreline buffer that helps keep the water temperature in the pond cooler.

Researchers will complete a hydrologic analysis of the existing conditions to determine the retrofitted pond size, along with a detailed planting plan for the perimeter of the retrofitted pond. The research team believes that retrofitting existing stormwater management ponds with red sand filter technology will reduce overall phosphorus loadings and improve the water quality.

The water quality at the site will be monitored for one year before and after construction, after which the team will evaluate the performance of this technology. If the project is successful, red sand technology could be applied at stormwater ponds throughout the Lake Simcoe watershed.

Reusing Treated Wastewater Effluent and Stormwater Runoff

The Province is currently working with the LSRCA on a project to evaluate the feasibility of reusing treated wastewater effluent and stormwater in the Lake Simcoe watershed. The study will be completed by July 2010. Within the Lake Simcoe watershed, there are 14 municipal STPs and one industrial wastewater treatment facility, all of which contribute to phosphorus loading. Some of the potential options for reusing treated wastewater effluent discharged from the STPs include:

  • “purple pipe” systems in new homes, businesses, industry and public facilities to re-use treated effluent to flush toilets and water lawns (non-potable water);
  • irrigation of golf courses, sod farms and lawns; and,
  • maintaining environmental flows in some watercourses.

Specific reuse opportunities that will be examined in this project include reusing water for urban, industrial, agricultural and environmental augmentation purposes. Some of the benefits of reusing wastewater include:

  • reducing stress on groundwater and surface waters;
  • maintaining groundwater levels and environmental flows within watercourses;
  • improving receiving surface water quality; and,
  • reducing costs associated with infrastructure needs.

Another consideration that will be evaluated as part of the planning approach for the water reuse system involves gauging and reporting on stakeholder and public acceptance of potential reuse applications. This information would be used to help develop recommendations on the potential applications for water reuse.

Water Quality Trading

In early 2010, the Ministry of the Environment released and consulted on a Feasibility Study for Water Quality Trading in the Lake Simcoe Watershed. The feasibility study concluded that a water quality trading program in the Lake Simcoe watershed is technically feasible, and that, subject to being accepted by watershed stakeholders, it could play a meaningful role in helping to reduce phosphorus inputs to Lake Simcoe.

Water quality trading uses economic instruments to help achieve environmental outcomes, such as reduced inputs of phosphorus. It provides a way for dischargers that cannot realistically reduce pollutant loads immediately to comply with pollutant reduction goals in the short term, allowing time for long term solutions to be developed. For example, a sewage treatment plant facing high costs to accommodate new growth or meet lower discharge limits could “trade” for discharge reduction credits that are voluntarily generated by another source having lower costs, such as an agricultural operation implementing conservation measures. Because reducing phosphorus essentially takes on monetary value, water quality trading has the potential to encourage innovation in pollution control technologies.

Based on feedback received during consultation, the Ministry intends to further evaluate water quality trading in consultation with watershed stakeholders before making a decision on whether or not to develop a water quality trading regulation and program for the Lake Simcoe watershed. If a decision is then made to proceed with developing a regulation and program, the Phosphorus Reduction Strategy could be revised to reflect this.

8. Conclusion And Moving Forward

This Strategy is presented as a starting point – the point where we must make choices, and show the commitment needed, to get to our goal of a dissolved oxygen concentration of 7 mg/L, or annual phosphorus load of 44 T/yr.

There is no way to be completely certain today that all of the actions recommended here, and those to come from the ongoing research being done, will get us there. This Strategy is a culmination of the best science of today, and a measured consideration of what can be reasonably achieved with the current available technology for stormwater and wastewater treatment. It assumes best efforts from the agricultural sector, and those who live on the Lake and tributaries as critical partners moving into the future.

We are confident that the ecological health of the Lake and its watershed can be protected and restored through continued stewardship efforts, targeted research, new and innovative technology for wastewater and stormwater management, and a commitment to managing the watershed and its resources in a sustainable manner.

The long term goal of the Phosphorus Reduction Strategy is to reduce phosphorus loading to Lake Simcoe to meet the Lake Simcoe Protection Plan’s dissolved oxygen target of 7 mg/L. However, this target also represents the means to a broader, more important end. Ultimately, the Plan’s goal is to restore Lake Simcoe and its watershed to a healthy and sustainable condition for the longer term — to ensure that the Lake’s important resources, environmental values and contribution to Ontario’s quality of life are restored and protected, and that they continue to be enjoyed for generations to come.

We will continue to rely on the adaptive management approach moving forward, with regular reviews and updates to this Strategy. Significant changes in direction or content coming out of new science or technological advances will be formulated in consultation with all stakeholders.

For further information

To obtain additional information on the Lake Simcoe phosphorus problem, please visit Ontario’s Protecting Lake Simcoe website. Further information can also be obtained by contacting the Ministry of the Environment’s Public Information Centre at 1-800-565-4923.

Appendix A: More Information On Sewage Treatment Plants (STPs)

There are currently 14 municipal STPs and one industrial STP in the Lake Simcoe watershed. Seven of the STPs discharge directly into Lake Simcoe, while the other eight discharge into watercourses that flow into the lake. The average annual phosphorus load from the 14 municipal STPs between 2002 and 2007 was approximately 5 T/yr, which represents about seven per cent of the total phosphorus load to the lake. Figure A1 below shows the historical annual average phosphorus loads from the STPs, in comparison to both the current Certificate of Approval (CofA) aggregate limit and the Interim Regulation limit.

Figure A1: Historical Annual Average Phosphorus Loads from the STPs

This bar graph shows the Historical Annual Average Phosphorus Loads from the sewage treatment plants in the Lake Simcoe watershed between 1995 and 2008, relative to the interim regulation limit and the new Certificate of Approval limit.

Enlarge this image.

The proposed Phosphorus Reduction Strategy establishes a baseline load for each STP to be reached by 2015 that would result in an aggregate load for all STPs of 7.2 T/yr. The proportional reduction of the load resulting from the 14 municipal STPs and one industrial STP in the Lake Simcoe watershed would be 7% of 44 T/yr which results in a total aggregate load of 3.2 T/yr.

Tiered Baseline Loading Limit for 2015

Implementation for the STP source will begin with categorization of the existing STP facilities into tiers, differentiated based on current Certificate of Approval loads, which then further define the effluent requirements for each tier. The details of the categorization and effluent requirements are presented in Table A1.

Table A1: STP Tiers
TierTier Criterion (P loading⁄year)Effluent Objective (mg/L P)Compliance Limit (mg/L P)
1>1000 kg/yr P0.070.10
2<1000 kg/yr P0.100.12
3<500 kg/yr P0.100.15
4Lagoons0.250.25

The individual STP tiers and baseline loads, which are based on current Certificate of Approval rated capacities and tiered effluent requirements, are presented in Table A2. The resultant aggregate load from all STPs is 7.2 tonnes of phosphorus per year, which is slightly less than the 7.3 T/yr phosphorus specified in the Interim Regulation.

The proposed compliance limit shown in the table was compared to the compliance limit in the current Certificate of Approval for each plant and the lower concentration was used to calculate the tiered baseline loads.

The tiered baseline concentration and loads shown in Table A2 would be applied to each STP at their next expansion or by 2015, whichever occurs first. This would allow for a period of “stabilization” and enable the municipal and private owners to plan any required upgrades or expansions. Where the concentration and loads are the same as the limits in their current CofA, they will be applied immediately. Note that these tiers and limits are minimum treatment standards and only apply for the purpose of determining the baseline loads. Future expansions of the STPs would need to meet the individual load caps, shown in Table A2, and would need to reduce the corresponding effluent concentrations accordingly.

Table A2: STP Tier Classification and Compliance Limits and Loads
STPTierTiered Phosphorus Compliance Limit (mg/L)footnote 3C of A Rated Capacity
(m3/d)
Tiered Baseline Compliance Load (kg/yr P)footnote 4
Uxbridge Brook WPCP30.155,221286
Beaver River # 1 WPCP (Sunderland)40.2563258
Lake Simcoe (Beaverton) WPCP30.154,550190
Beaver River # 2 WPCP (Cannington)40.251,06897
Schomberg WPCP30.1footnote 52,05575
Sutton WPCP30.153,412187
Keswick WPCPfootnote 620.1footnote 518,000/24,000655/876
Mount Albert WPCP30.1footnote 52,04075
Queensville / Holland Landing Lagoon WPCP40.251,364124
Barrie WPCC10.176,0002,774
Bradford WPCP20.1footnote 517,400698
Innisfil WPCP20.1214,370629
Orillia WTCC10.127,300996
Lagoon City STP30.152,273124
Silani Cheese STP30.2530027

Total: 6,995/7,216

The baseline concentration and load for Silani cheese was calculated to accommodate their process requirements, as they are an industrial, not a municipal wastewater facility.

All of the STPs, with the exception of Orillia and possibly Lagoon City, should be able to meet the tiered baseline compliance loads using existing in-plant technology (See Table A3 below).

Orillia is a conventional secondary STP, which presently has a phosphorus compliance limit of 0.3 mg/L. Actual performance data for the period 2006 to 2008 show an average concentration of 0.18 mg/L of phosphorus in the final effluent, at an average flow of about 70% of the rated capacity. This is equivalent to an annual phosphorus load of about 1,274 kg/yr, which exceeds the baseline compliance load of 996 kg/yr. In order to achieve the required tiered baseline phosphorous effluent concentration of 0.1 mg/L P and the associated load, the Orillia STP will need to add conventional tertiary filtration. It is estimated that the cost of adding filtration will be about $4.0 million.

The Lagoon City STP presently has a phosphorus compliance limit of 0.3 mg/L. Over the period 2006 to 2008, the Lagoon City STP discharged an average effluent phosphorus concentration of 1.8 mg/L, at an average flow of about 64% of rated capacity. Based on this performance it is possible that the STP could achieve the tiered baseline effluent phosphorus concentration of 0.15 mg/L, up to the plant’s rated capacity. Therefore, it is assumed that no upgrade would be required in order for the Lagoon City STP to comply with the tiered baseline compliance concentration and load.

Table A3: Projected Costs to meet Baseline Compliance Limits
STPCurrent TP Compliance Limit (mg/L)2015 Baseline Tiered Concentration (mg/L)Treatment ProcessUpgrade requirements to meet 2015 baseline concentrationCapital Cost (CAD)
Uxbridge Brook WPCP0.150.15Extended Aeration + Tertiary FiltrationNo upgrades required.-
Beaver River # 1 WPCP (Sunderland)0.30.25LagoonNo upgrades required - based on actual recent effluent concentrations-
Lake Simcoe (Beaverton) WPCP0.30.15Extended Aeration + Solids Contact ClarifierNo upgrades required - based on actual recent effluent concentrations-
Beaver River # 2 WPCP (Cannington)10.25LagoonTreatment optimization required - i.e. P removal if not already being done-
Schomberg WPCP0.10.1Extended Aeration + Tertiary FiltrationNo upgrades required-
Sutton WPCP0.180.15SBR + Tertiary Filtration (Continuous Backwash Upflow Sand Filter)No upgrades required-
Holland Landing WPCP0.30.25LagoonNo upgrades required - based on actual recent effluent concentrations-
Keswick WPCP0.10.1Extended Aeration + Ultra-filtration MembraneNo upgrades required-
Mount Albert WPCP0.10.1Extended Aeration + Tertiary Filtration (Continuous Backwash Deep-bed Filter)No upgrades required-
Barrie WPCC0.180.1UNOX + RBC + Nitrification + Tertiary Filtration (Automatic Backwash Shallow Bed Single Media Filter)No capital upgrades required. Process optimization to achieve effluent TP of 0.10 mg/L.-
Bradford WPCP0.110.11Extended Aeration/SBR + Tertiary Filtration (Continuous Backwash Upflow Deep-bed Granular Media Filter)No upgrades required.-
Innisfil WPCP0.30.12Extended Aeration + Tertiary Filtration (Automatic Backwash Dual Media Filter/Continuous Contact Deep-bed Filter)No upgrades required-
Orillia WTCC0.30.1Conventional Activated SludgeInstallation of tertiary filtration$4.0M
Lagoon City STP0.30.15Extended AerationNo upgrades required - based on actual recent effluent concentrations-
Silani Cheese STP0.30.25Biological Activated Sludge + FiltrationNo capital upgrades required. Process optimization to achieve effluent TP of 0.25 mg/L.-
Overall    $4.0M

Appendix B – More Information On Urban Stormwater Runoff

Figure B1 shows a comparison of the ability of different stormwater management facilities in removing phosphorus

Figure B1: Phosphorus removal by type of facility

This image shows the expected phosphorus removal percentage with error bars for several types of stormwater management facility. These are: dry ponds, wet ponds, wetlands, filtering practices, bioretention, infiltration practices, and open channels.

Source: extracted from Imbrium Systems 2009 Webinar session, original source from ‘Centre for Watershed Protection’, National Pollutant Performance Removal Database v3, Maryland State, September 2007

Appendix C: More Information On Stewardship And Community Action:

There is evidence to indicate that stewardship may be the most cost-effective way to address environmental issues such as phosphorus loading from non-point sources such as agriculture. Careful monitoring and assessment of the results of stewardship efforts is needed to ensure a continued focus on priority areas. Over time and with continued efforts, the science required to measure stewardship’s environmental impacts will improve.

Stewardship in the Lake Simcoe Watershed:

Broad-based environmental stewardship programs that combine education with financial incentives are successful because they encourage land management and behavioural changes that sustain long-term environmental benefits, commonly referred to as “Best Management Practices” or BMPs. Some stewardship programs have already adapted to provide an increased focus on phosphorus management. Existing programs include:

  • The Landowner Environmental Assistance Program (LEAP), is managed by the Lake Simcoe Region Conservation Authority (LSRCA). This program offers incentives to landowners for projects such as tree-planting; decommissioning of unused wells, manure management and clean-water diversion on farms; and stream restoration to name a few. The LSRCA estimates that LEAP has contributed to a reduction of 18 metric tonnes of phosphorus entering the lake over the last 20 years (LEAP website).
  • The Environmental Farm Plan (EFP) and related cost-sharing is administered by the Ontario Federation of Agriculture and delivered by the Ontario Soil and Crop Improvement Association. This program is offered across Canada and provides incentives for projects such as building manure storages; constructing run-off management structures; modifying tillage equipment to reduce soil erosion, and many more (EFP website).
  • The Lake Simcoe Farm Stewardship Program funded by the Ministry of the Environment (MOE), offers added incentives to the Environmental Farm Plan (EFP) cost-share program for phosphorus management practices, such as fertilizer management; manure storage, and soil/nutrient testing (Lake Simcoe Stewardship Program website).
  • The Lake Simcoe Community Stewardship Program, currently delivered by Ontario Stewardship Councils in partnership with the province, parallels the EFP approach by using a stewardship guide, educational workshops, and links to financial and technical resources for non-farm landowners to promote improved land stewardship for phosphorus management (Lake Simcoe Stewardship Program website).
  • Environment Canada’s Lake Simcoe Cleanup Fund provides funding for numerous watershed projects focused on phosphorus management, including: tree-planting in riparian areas; water re-use; and stream and wetland restoration (Lake Simcoe’s Clean-up Fund website).
  • Numerous Non-Governmental Organizations (NGOs) and community groups also participate in watershed stewardship efforts. For example, the Ladies of the Lake Conservation Association has established a website to help information sharing on environmental activities throughout the watershed. For more information, visit Our Lake Simcoe website.

This increased interest in watershed stewardship is evidence that the Lake Simcoe Protection Plan is encouraging people to help to reduce phosphorus loading and protect the Lake Simcoe ecosystem. More information on how you can make a difference is available online at Ontario’s Lake Simcoe website.

Appendix D: More Information On Modelling

Watershed modelling study: subwatershed targets

This study is developing a model of the phosphorus load from each subwatershed that feeds into Lake Simcoe (See Figure D1), and is expected to be completed later this spring/summer. The study takes a number of complex factors and variables into account, such as the projected population and employment growth forecasts in the Growth Plan for the Greater Golden Horseshoe and the types of land uses likely to be in place by 2031.

Figure D1: Lake Simcoe Subwatersheds

This map shows the subwatersheds that make up the Lake Simcoe watershed. These are: Barrie Creeks; Beaver River; Beaverton Creeks; Black River; Carthew Bay Creeks; East Holland; Fox Island; Georgina Creeks; Georgina Island; Hawkestone Creek; Hewitts Creek; Innisfil Creeks; Jackson’s Point Creeks; Keswick Creeks; Lovers Creek; Maskinonge; Oro North Creeks; Oro South Creeks; Pefferlaw River; Ramara Creeks; Snake Island; Talbot Creeks; Talbot River; Thorah Island; West Holland; Whites Creek.

The total phosphorus load from each subwatershed to Lake Simcoe will be compared to the total phosphorus-loading goal of 44 T/yr. The resulting analysis will allow researchers to develop goals for each subwatershed, to help determine the priority areas for phosphorus load reductions. If a subwatershed contributes a comparatively high phosphorus load, for example, and has significant opportunities for reducing the phosphorus through specific actions, that subwatershed may receive a higher priority for action (LSPP 8.1-SA requires each subwatershed to be evaluated in this way).

This study will develop a model for 2031, based on the projected estimates of population growth currently available. The analysis will begin by using the projected growth for each municipality to 2031 to determine how much phosphorus would enter the lake if there were no phosphorus reduction strategy in place. The projected growth will be used along with the projected land uses in the subwatershed to evaluate the amount of phosphorus that is expected to enter the lake in the absence of any actions.

The model’s analysis predict the resulting phosphorus contribution from each subwatershed area using different values for the phosphorus and nitrogen concentrations, based on land use and soil types. Point source loads such as STPs and septic systems are included in the analysis, along with outflows from stormwater management facilities.

The next and most important part of the modelling is to work out various scenarios that predict the impact of different actions that could be included in the phosphorus reduction strategy. These scenarios should reveal the potential improvements available from measures such as implementing best management practices (BMPs) and upgrading STPs—including which measures have the greatest potential, are most cost-effective, and where they should be implemented.

This part of the subwatershed modelling study will be performed through a partnership with the Ministry of the Environment and the Lake Simcoe Region Conservation Authority using the CANWET model, which was developed and used in the 2006 Assimilative Capacity Study and updated in 2008.

These initiatives will result in refined estimates of the phosphorus loading contributed from each source in each subwatershed, as well as targets for reductions. The next version of the Phosphorus Reduction Strategy will be adapted to incorporate these subwatershed targets.

Lake Simcoe Modelling Study: lake and sub-lake targets

The Lake Simcoe Protection Plan targets a concentration of 7 mg/L of dissolved oxygen in the deepest, coldest waters of the lake which translates to a total phosphorus load of 44 T/yr based on the best available information. This study will perform detailed modelling of Lake Simcoe to further explore the relationship between phosphorus loadings to the lake and the concentration of dissolved oxygen, using several different modelling methods.

Simple, steady-state, models will be used to test the relationship between phosphorus loading and phosphorus concentration in the lake and empirical models will be evaluated to test the connection between lake phosphorus concentrations and dissolved oxygen.

As part of this work, the research team will assess the adaptive capacity of the lake and will use a dissolved oxygen model to analyze the three basins: Cook’s Bay, Kempenfelt Bay and the main basin. This analysis will help answer questions about whether it is appropriate or useful to develop a different phosphorus reduction strategy for different parts of Lake Simcoe.

Early modelling results suggest that the water in Lake Simcoe mixes well, and that separate strategies for different parts of the lake may not be necessary. To provide a definitive answer, however, researchers will use a three-dimensional hydrodynamic model to evaluate the relationship between the three basins. This model will be used to provide additional information on the relationships between phosphorus and deep water dissolved oxygen.

PIBS 7633e