The state Department of Transportation today released an environmental impact statement on improvements at four harbors to support large-capacity ferry vessel operations.

The EIS was ordered under Act 2, approved late in 2007 to allow Hawaii Superferry and other "large-capacity" ferries to operate before environmental studies are conducted.

The study does not evaluate Superferry operations. However, since the improvements would allow large ferries to the use the harbors, it does consider the consequences of ferry operations, in general, as secondary impacts.

Direct impacts cited in the EIS include displacement of fishing, surfing and other cultural activities near the west breakwater of Kahului Harbor on Maui, where a new ferry berth is proposed.

The report also said a ferry pier at Kawaihae Harbor on the Big Island may result in potentially significant and adverse impacts on nearby Pu'ukohola Heiau National Historic Park. These impacts include construction noise and vibrations, and intrusion on views from the heiau.

Indirect impacts cited in the EIS include increased road traffic as a result of ferry visits and the potential loss of natural resources.

Cumulative impacts from increased ferry operations in Hawai'i include the potential for vessel collisions with humpback whales and the interisland dispersal of invasive species, according to the study.

The report notes that agricultural inspections, road improvements and other measures could mitigate most of the impacts.

The EIS said the benefits of ferry services include assisting response efforts in the event of a natural disaster or other emergency.

Copies of the document are available at public libraries statewide. Electronic copies are available online on the Department of Transportation Web site at: www.hawaii.gov/dot/harbors.

The public has 45 days — in this case, until Feb. 23 — to submit comments on the EIS. Written comments should be mailed or faxed to: Katherine Kealoha, Director, Office of Environmental Quality Control, 235 S. Beretania St., Suite 702, Honolulu , HI 96813, fax 808-586-4186; and Michael D. Formby, Deputy Director, Department of Transportation Harbors Division, 79 S. Nimitz Highway, Honolulu, HI 96813, fax 808-587-3652.