Addressing Concerns for Water Quality Impacts
from Large-Scale Great Lakes Aquaculture

Based on a Roundtable
Co-hosted by the Habitat Advisory Board of the Great Lakes Fishery Commission
the Great Lakes Water Quality Board of the International Joint Commission

August, 1999


Aquaculture - Experiences and Lessons: Ontario Ministry of Natural Resources

by Alan Sippel and Mark Muschett
Fish Culture Section, Fish and Wildlife Branch, Ontario Ministry of Natural Resources, PO Box 7000, 300 Water Street, Peterborough, Ontario, Canada K9J 8M5

In Ontario, fish culture has been practiced since the turn of the century by the provincial government, mainly for lake and stream stocking. Fish culture remained exclusively a government endeavor until 1962 when changes were made to Ontario's Game and Fish Act. This allowed the private sector to raise and sell rainbow and brook trout for human consumption or for stocking purposes, and smallmouth and largemouth bass for stocking only. In 1995, the regulations were changed to make over 40 species eligible for aquaculture.

Aquaculture or fish farming is a small but growing industry in Ontario. The province is well-suited for aquaculture because of its abundant high-quality water resources and its proximity to large markets in Canada and the United States. In 1997, some 4,250 tonnes of rainbow trout were produced in approximately 200 facilities with a farm gate value of about $23 million (Cdn.). This results in an estimated $65 million (Cdn.) contribution to the provincial economy and creates over 500 person-years of employment. Rainbow trout are the predominate species. Other species, including tilapia, arctic char, bass, and baitfish, are also produced commercially, but to a much lesser extent (total production value about $1 million (Cdn.)).

Most aquaculture facilities are located in southern and central Ontario, though there has been expansion in Northern Ontario, particularly in the waters of Georgian Bay and the North Channel of Lake Huron. The industry is comprised of numerous small-scale, essentially part-time operations, with fewer mid-sized and large-scale operations. Based on 1996 industry statistics, about 80% of the production total for the entire province came from only 8 large farms and 91% of production came from 20 farms. The best available estimates suggest that cage culture accounts for 70% of provincial production. Land-based ponds, circular tanks and raceways, as well as cages located in public waters, reflect the range of production technology used in aquaculture.

The Ontario Ministry of Natural Resources (OMNR) operates 10 provincial fish culture stations to culture fish for stocking. The stations are geographically distributed across the province. Lake trout, brook trout, and splake are the primary species but rainbow trout, brown trout, coho salmon, chinook salmon, Atlantic salmon, whitefish, and walleye are also produced. OMNR facilities produce between 8 and 10 million fish per year.

More than 12 federal and provincial agencies and 30 pieces of legislation potentially impact on the aquaculture industry. OMNR is the main licensing and permitting agency. OMNR issues the Aquaculture Licence which regulates where aquaculture can occur and which species can be cultured at any given location. Other licence conditions include a requirement to report specified disease agents, a requirement to maintain escape-prevention devices, and a requirement to report escapes above a specified number. For cage culture operations, there is also a licence condition to monitor and report on specified water quality parameters. Although there is a requirement to report the presence of specified disease agents, there is no requirement to monitor for those agents. The water quality monitoring and reporting requirements are being developed by the Ontario Ministry of the Environment (OMOE). OMNR also administers the Public Lands Act which governs the use of Crown or public lands in Ontario. A Land Use Permit is issued to provide a degree of tenure to cage culture operations on public waters.

Land-based fish culture operations that use more than 50,000 liters of water per day must obtain a Permit to Take Water from OMOE. OMOE is also responsible for issuing the Certificate of Approval to Discharge which regulates the quality of water being discharged from a culture facility. Neither the Permit to Take Water nor the Certificate of Approval to Discharge apply to cage culture operations.

Fisheries and Oceans Canada reviews proposals for cage culture operations to ensure that fisheries habitat concerns are protected. Canada Coast Guard must also review and approve cage culture operations from a navigation safety perspective.

Drug and chemical use at fish culture facilities is regulated by Agriculture and Agri-Food Canada through the Feeds Act and Pest Control Products Act and by Health Canada through the Food and Drug Act. A survey of commercial aquaculture operations suggests that very little drug and chemical use is occurring.

OMNR fish culture facilities approached the problem of improving effluent water quality by focusing on feed quality and diet design, as well as feeding practices. Substantial improvements in effluent water quality were achieved by reducing the phosphorus content and using highly digestible feedstuffs in the fish feed and by reducing feed wastage. Also, OMNR has modeled fish growth, feed and oxygen requirements, and waste production for critical water quality parameters. A computer program, Fish-PrFEQ, is under development for use as a hatchery management tool, to assist with controlling waste outputs from fish hatchery operations. A test version of this model is available on the Internet at

Furthermore, all OMNR fish hatcheries monitor effluent water quality. Most stations constructed or substantially modified since 1988 have had effluent treatment facilities installed and are required to report this information to the OMOE as a condition of their Certificates of Approval to Operate Sewage Treatment Works. All stations are expected to meet OMOE compliance limits for phosphorus and solids as the minimum standard of effluent water quality.

OMNR, in collaboration with the University of Guelph and cooperating institutions in other countries, has co-hosted a number of international symposia concerning the development of environmentally-responsible aquaculture. Industry approaches to mitigation are discussed elsewhere.

Suggestions for improving the ability to improve water quality protection include:


Cho, C.Y. and D.P. Bureau. 1998. Development of bioenergetic models and the Fish-PrFEQ software to estimate the production, feeding ration and waste output in aquaculture. Aquat. Living Resour. 11(4) 199-210.

Cho, C.Y. and D.P. Bureau. 1997. Reduction in the waste output from salmonid aquaculture through feeds and feeding. Progress. Fish Cult. 59 155-160.

Cho, C.Y. J.D. Hynes, K.R. Wood, H.K. Yoshida. 1991. Quantitation of fish cultures wastes by biological (nutritional) and chemical (limnological) methods: the development of high nutrient dense (HND) diets, IN Cowey C.B., Cho, C.Y., (Eds.). Nutritional Strategies and Aquaculture Waste, Proceedings of the 1st International Symposium on Nutritional Strategies and Management of Aquaculture Waste, University of Guelph, Ontario, Canada. pp. 37-50.

Cho, C.Y. J.D. Hynes, K.R. Wood, H.K. Yoshida. 1994. Development of high nutrient-dense, low pollution diets and prediction of aquaculture wastes using biological approaches. Aquaculture 124 293-305.

Moccia, R.D. and D.J. Bevan. 1996. Aquaculture legislation in Ontario. University of Guelph, Aquaculture Extension Centre. AEC Order No. 96-002.

Thornburn, M.A. and R.D. Moccia. 1993. Use of chemotherapeutants on trout farms in Ontario. Journal of Aquatic Animal Health 5: 85-91.