Wielechowski, an Anchorage Democrat, said the cruise ship industry dramatically outspent the initiative backers in 2006, but voters still backed the measure, the result of cruise ships' history of polluting in Alaska and elsewhere.

During Tuesday's floor debate, he listed a series of violations, starting with a 1998 case against Holland America for discharging oily bilge water in Alaska waters that resulted in a felony conviction, a $1 million fine and $1 million in restitution. To say that DEC can be trusted in enforcing the highest standards is misleading, he said. Permit requirements vary from ship to ship, based on the equipment aboard that ship, he said.

Egan, Juneau's sole senator and part of the GOP majority, said the travel industry is his district's biggest employer -- bigger than fishing, bigger than health care -- yet he opposed the bill because he wants the cruise industry to meet the highest standards.

A measure supporter, Sen. Lesil McGuire, R-Anchorage, said voters may have been confused by ballot language in 2006 that indicated the measure was just to make cruise ships meet the same standards as everyone else.

In 2009, the Legislature delayed the effective date of the voter-backed requirements until 2015 and created a science panel to determine whether treatment systems existed to meet those standards.

The panel issued a draft report in November that said while the technology was available in land-based treatment programs, such ship-board technology did not yet exist. The report said discharges below the water quality standards wouldn't cause environmental damage, though one dissenting member -- the sole independent scientist on the panel -- said the report minimized the potential for harm.

Officials with the state Department of Environmental Conversation assured the science panel its preliminary work wouldn't be used to craft legislation, but Gov. Sean Parnell's proposal explicitly cited the panel's work as its basis. Giessel told reporters Tuesday the DEC had told the panel its work would be used in developing legislation.

Fishing groups, environmentalists, Alaska Native organizations and residents of coastal communities spoke against the measure.

The bill was passed quickly in the House, where lawmakers spent about four hours debating it during hearings, said Democratic House Minority Leader Beth Kerttula.

The measure also extends wastewater discharge permits from the current three years to five years.

It is effective immediately.

Daily News reporter Rich Mauer contributed to this story. Reach Lisa Demer at ldemer@adn.com.