TRAVERSE CITY, Mich. (AP) -- State officials approved a significant expansion of a northern Michigan commercial fish hatchery's operations Tuesday after requiring additional measures to protect the cherished Au Sable River.
The Michigan Department of Environmental Quality granted a pollutant discharge permit to Harrietta Hills Trout Farm LLC to increase production from about 20,000 pounds of rainbow trout a year to 300,000 pounds, which owner Dan Vogler says is essential to make the business profitable.
Sport angler groups had raised questions about the proposal because the hatchery would flush water containing phosphorus and solid particles -- including fish excrement and uneaten food -- into the Au Sable, known for its clean waters and abundant wild trout population.
DEQ spokesman Brad Wurfel said the agency strengthened requirements in the permit after hearing from the public. If the aquaculture operation abides by the conditions, there should be no degradation of water quality, he said.
"What we've established has unusually tight controls and unusually high monitoring standards," Wurfel said. "We'll be watching this very carefully moving forward. We stand by the permit we issued today as being durable and effective protection for the Au Sable River."
Built a century ago, the hatchery once was owned and operated by the state Department of Natural Resources. Crawford County now owns the facility and leases it to Harrietta Hills, which also has a fish farm near Cadillac.
The Grayling hatchery is a tourist attraction that draws thousands of visitors each year to see the fish swimming in concrete runways. Vogler said the revenue it generates isn't enough to cover costs of running the operation.
"I think the DEQ has developed a permit that is adequately protective," Vogler said. "We understand the sensitivity of the resource and we're not going to do anything to damage it."
Even with the expansion, the hatchery would be small by national standards, he added. "In Idaho, a small producer is a million-pound farm."
Vogler said his company plans to improve the discharge system, which presently sends water into two lagoon areas, then into the Au Sable.
Under the permit, if discharge standards are violated, the hatchery can be prohibited from boosting the number of fish until the problems are fixed.
The hatchery will be required to submit a plan for best management practices and conduct additional water quality monitoring. The permit also sets additional phosphorus limits during the April-through-September growing season.