With excitement and many waves -- the emotional human kind as well as the watery kind -- RiverQuest's new flagship, Explorer, traveled through the Emsworth Lock and Dam yesterday, then cruised briskly up the Ohio River to make its grand arrival at the Point.

"Welcome to Pittsburgh," one person on the four-boat welcoming flotilla said over the airwaves about 10 a.m. as the vessel left the dam behind and proceeded on the final two miles of its 1,600-mile journey, which began 10 days earlier at the Steiner Boatyard in Bayou La Batre, Ala.

The $3.5 million "green" vessel, the first ever built, was built in Florida, then traveled up the Mississippi and Ohio rivers to Pittsburgh. The crew of seven lived aboard the boat and cruised upriver at an 8-mph clip for 24 hours a day, and it handled "like a dream."

It soon will replace Discovery, an old naval vessel that has served as RiverQuest's flagship vessel for years.

"It was most exciting to come through the locks and dam and see the Discovery and our staff with their fresh new RiverQuest shirts and the yachts with friends and family cheering us on," RiverQuest Executive Director Karl Thomas said. "We made a victory tour up the rivers. A vision becoming a reality is very satisfying."

RiverQuest, formerly Pittsburgh Voyager, is a not-for-profit education organization that offers river-based educational programs for students, teachers and the community. It also provides cruises and private charters for businesses, organizations and the public.

Its program goal is to connect people to their environment through educational adventures. Since its launch in 1995, RiverQuest has had 80,000 people on board its vessels, including 64,000 students from 239 schools and 66 school districts.

Explorer's arrival will allow the program to expand.

Discovery carries only 39 passengers and a crew of three, but Explorer will carry 150 passengers and a crew of 20. The result will be "an order of magnitude shift in our program," Mr. Thomas said.

Once the Coast Guard inspects the 90-foot vessel, Explorer will be used as a "floating laboratory" and "floating classroom," RiverQuest President Jim Roddey said. The boat is expected to go into service sometime in mid-September.

Explorer's foremost feature is its green design, which makes it environmentally friendly.

It features a hydrid biodiesel-blended fuel/electric engine designed by Siemens Energy & Automation, with special lighting, windows, construction materials and other features that meet or exceed the Leadership in Energy and Environmental Design, or LEED, green-building standards. Explorer is the first boat ever designed and built according to the standards, RiverQuest officials said.

Explorer's carbon footprint -- the measurement of all greenhouse gases it produces -- still must be calculated, but Mr. Thomas expects it to be much smaller than Discovery's.

In 2006, Explorer was named by Work Boat magazine as one of the 10 most significant boats built in the United States that year, due to its green technology, which comes at a steep price. But the boat is expected to save money and have less environmental impact over the long haul.

"Making it a green boat added a million to the cost," Mr. Roddey said, noting, however, that the boat exemplifies the importance of environmental awareness and the rivers' importance to the region.

With Explorer now docked outside the Carnegie Science Center on the North Side, Discovery soon will be retired, he said.

Pittsburgh has a larger natural water supply than any other city in the United States, and RiverQuest encourages people to preserve that resource, Mr. Roddey said. Availability of water soon could become as strategic a political issue as oil, he said.

Mr. Thomas said Explorer gives focus to Pittsburgh's three rivers. For now, Downtown lacks places for people to dock. The city could become a river tourist destination.

"I think the boat is symbolic of the transformation of Pittsburgh, and I hope the community embraces it and sees Pittsburgh in a way the world sees it," Mr. Thomas said, noting the boat symbolizes Pittsburgh's transformation from old to new. That transition should include a reinterpretation and better use of local rivers.

"We just have to realize it ourselves," he said.