Of the six cruise ships currently permitted to discharge treated wastewater while anchored in Alaskan ports, two are making a total of 14 dockings in Haines this summer.

Holland America’s Zaandam, scheduled for nine dockings this summer, is allowed to dump treated human waste, known as “blackwater,” into Portage Cove while it is tied up at the Port Chilkoot Dock. Compagnie du Ponant’s L’Austral, set for five dockings this year, also can discharge blackwater at the dock.

Princess Cruises’ Golden Princess, which will dock here twice this summer, can’t discharge treated human waste, but can dump shower, sink, kitchen and laundry runoff called “graywater” while moored at the dock.

Department of Environmental Conservation environmental program specialist Ed White said the agency uses a computer modeling program to determine which ships get the permits. The program uses information from the ship – volume of water discharged, at what rate – to predict whether the discharged material will exceed water quality standards once it is diluted in a “mixing zone.”

The mixing zone in harbors is about 83 meters from the point where the discharge is dumped, White said. That means instead of the water having to meet standards at the “end of pipe,” or once it comes out of the ship, a sample taken from a maximum of 83 meters away from the ship must meet the requirements.

Haines resident Gershon Cohen, a water quality consultant, said he takes issue with the “mixing zone” theory and the computer-modeling system. Cohen worked as a consultant under multiple administrations, including for the Water Quality Standards Advisory Group and a task force on cruise ship discharge.

Cohen said the computer-modeling system is flawed because it isn’t verified by actual samples; it’s just a prediction of how the discharge will dilute in water. “They model what the mixing zone should be and they just assume that the model works,” Cohen said.

Factors like salinity, temperature, underwater topography and other variables can affect how discharge mixes into the water, Cohen said. “You might not be getting that level of dilution and level of safety,” he said.

White acknowledged the model isn’t specific to individual ports and samples haven’t yet been taken to verify the mixing zone computer-modeling system. This year DEC hopes to start sampling in Juneau and Skagway, and the agency will get to Haines “eventually,” White said.

“It’s a multi-year project,” he said.

Another problem with the system, Cohen said, is it doesn’t take into account multiple ships dumping into the same area multiple times. “There is a presumption that you are discharging into clean water. If you are discharging into an area that has just been dumped into, that affects it,” Cohen said. “The fact that you are diluting (discharge) with a larger body of water, you are still loading that body of water with metals day after day after day.”

John Binkley, president of Alaska’s Cruise Lines International Association chapter, said the treatment systems aboard cruise ships are so state-of-the-art he drinks the discharge water. “It’s a very, very high quality,” Binkley said.

Binkley said if he was a member of a small community like Haines, he would be more concerned about what municipal treatment systems are discharging into local waters, rather than “the high quality of wastewater discharged from cruise ships.”

In an ideal world, municipalities would hook up to cruise ships while they are in port and have their wastewater treated on board, Binkley said. “It would certainly improve the wastewater that the community is putting into the bay.”

Southeast Alaska Conservation Council’s communications director Daven Hafey said the organization is concerned about stationary discharge because of the proximity to urban centers and fishing grounds.

Materials of concern are copper, ammonia and zinc, Hafey said.