An odd red raft, rigged with a 10-foot pole topped with cameras, will be cruising the Baltimore Harbor and Patapsco River over the next few weeks.

The Chesapeake Conservancy and a Virginia technology company are using the pontoon boat to create a virtual portrait of the harbor and river as part of a multiyear project to photo-map more than 3,000 miles of the bay and its rivers — think Google Street View, but on the water.

The maps, available on the Annapolis-based environmental group's website or its free mobile app, will offer people a virtual tour of waterways most can't see — about 98 percent of the coast along the trail is private property.

The initiative is one way the Chesapeake Conservancy is trying to build public interest in the Chesapeake Bay and the Captain John Smith Chesapeake National Historic Trail, designated in 2006 as the first national waterway trail.

“Virtual tours of the Chesapeake rivers, the Baltimore Harbor and the John Smith Trail are one way we're using technology to inspire people to care for the Chesapeake, to encourage them to get outside and get on the water,” said Joel Dunn, the conservancy's CEO. “Because once you're on the water, you'll fall in love with the Chesapeake Bay, and once you fall in love with the Chesapeake Bay, you'll vote for it, you'll donate to it, you might even commit your career to it.”

The John Smith Trail follows the route explorer John Smith forged and mapped around the bay in the early 1600s.

Chesapeake Conservancy and Richmond-based Terrain360 began mapping the river trail, which reaches from Virginia to New York, last year. So far, they've mapped the James, Nanticoke and Susquehanna rivers, and Mallows Bay, part of the Potomac River.

In addition to Baltimore Harbor and the Patapsco River, they plan to map the rest of the Potomac River, and the Elk, Northeast, Rappahannock, Sassafras and York rivers.

The group will have mapped about two-thirds of the trail by the end of this year. They hope to complete the project next year, assuming funding comes through. The project has been paid for by a donation from a private organization. The group declined to name the donor and the amount.

To map the waterways, Chesapeake Conservancy and Terrain360 outfitted a pontoon boat with a 10-foot-tall pole topped with six cameras. The cameras take panoramic pictures every 40 feet, as the boat travels along the shore, moving at about 6 miles an hour.

Photos from the camera are later integrated to create a 360-degree view, similar to Google Street View.

Mapping Baltimore's harbor and the Patapsco will take a few weeks. The boat can't go out in the rain, because it would distort images and possibly damage the cameras. Obstacles such as trash, mud or seaweed can interfere with the boat's motor.

Ryan Krenshaw, a data collector for Terrain360 who has been operating the pontoon boat this summer, likes to get as close to the shore as possible, usually within 50 feet, which means keeping an eye out for shallow spots.

With the virtual map, the Chesapeake Conservancy is attempting to connect with digital-focused millennials, who, Dunn said, can shape how future generations address environmental issues. The group is especially interested in reaching young parents who want to expose their children to the outdoors, he said.

“We're riding the internet wave,” Dunn said.

The environmental group also wants businesses to get more involved, especially in Baltimore, where the harbor needs lots of help.

The harbor is polluted with millions of gallons of sewage, trash and stormwater runoff. In its annual Healthy Harbor report card, the Waterfront Partnership of Baltimore gave the harbor an F on four out of six quality measures, including fecal bacteria levels.

“The harbor is a beautiful place to stand and look out on, but people are smart — they know if you can swim in the harbor, fish and eat the fish, the local economy will be strengthened. They'll be able to attract more customers, residents,” said Laurie Schwartz, president of the Waterfront Partnership of Baltimore.

A usable waterfront could be a major draw for prospective employees of downtown Baltimore businesses, which is why businesses should have an interest in seeing Baltimore's harbor improved, Schwartz said.

Michael D. Hankin, CEO of Baltimore investment firm Brown Advisory and chairman of the partnership's board, said businesses often help behind the scenes, pushing issues with politicians, donating to environmental groups and supporting new initiatives.

“Businesses can play a bigger role by speaking up more and saying these things matter to everyone and they matter to us as businesses,” said Hankin, who also serves on Chesapeake Conservancy's board. “That's what we've tried to do.”

While in many areas, the group's photos will highlight sparking water and lush forests that users will — in theory — be eager to go explore, those for the Baltimore Harbor, while visually interesting, also will depict its polluted state.

That's not necessarily a bad thing, Schwartz said. As part of its effort to clean up the harbor, the partnership has made a point to highlight the harbor's problems and progress, with its annual report card and trash wheel, which collects trash where the Jones Falls enters the Inner Harbor.

The Chesapeake Conservancy's photo-map could have the same effect, she said.

“If they see trash floating in the water, we're hopeful that they'll see it as a crime, as a shame, and want to make our area as pristine as some other parts of the chesapeake,” Schwartz said.

sarah.gantz@baltsun.com

twitter.com/sarahgantz