Since it opened 21 years ago, the National Aquarium in Baltimore has explored the "world of water" from a fundamentally global perspective, treating visitors to re-creations of such exotic spots as an Amazon rain forest, an Atlantic coral reef and, soon, the Australian Outback.

Now a new waterfront project planned by the aquarium board promises to take the institution in a different direction, focusing on local habitats rather than faraway climes.

It also has the potential to give back to the community - and particularly, the local waterfront - in ways the original facility never could.

The Center for Aquatic Life and Conservation is the name of a multimillion-dollar facility that the aquarium wants to build on a six-acre "brownfields" site along the Middle Branch of the Patapsco River.

The building is being constructed to give the aquarium up to 70,000 square feet of space for its animal care and breeding programs, which currently occupy leased space in Fells Point, and a new location for the marine animal hospital now on Pier 4, including areas for quarantine, medical care and observation.

Directors also want it to contain space for the aquarium's education and conservation programs, including classrooms for school groups and meeting space for the community. They want to set it in a park-like environment that could help teach visitors about the fragile wetlands of the Chesapeake Bay and expose them to the Middle Branch shoreline.

No other American aquarium has a facility like this. What sets it apart are the setting and the design, which are intended to reaffirm the aquarium's position as a conservation-minded organization.

The Middle Branch is in many ways the opposite of the Inner Harbor - a green, natural waterfront as opposed to a manmade urban waterfront. City planners have taken steps to make sure it is never developed as intensively as the Inner Harbor has been, but they do want it to get more use as a recreational setting.

Even more so than with the buildings on Piers 3 and 4, aquarium directors are seeking an environmentally sensitive design that will provide for low energy consumption and reduced operating costs. They want a "green" building, incorporating ideas that will make the center a model for ecologically sound, energy-efficient urban development.

"It all goes back to [architect] Peter Chermayeff's vision of the aquarium as a place that can promote conservation," said Glenn Page, the aquarium's director of conservation. "If the Inner Harbor buildings represent our effort to think globally, this is a way to act locally."

"We want this to be an exhibit in itself," said Tawna Mertz, project director for the aquarium. "It will be a place where people can touch and feel the wetlands. It's an opportunity that doesn't exist in Baltimore or many other urban centers today."

The land, at 101 W. Cromwell St., is part of the Middle Branch Park and next to the Department of Public Works' central garage at 101 W. Dickson St. Although it qualifies as a "brownfields" parcel - an undeveloped or abandoned site where real or perceived contamination complicates redevelopment - it's a prominent site at the north end of the Hanover Street bridge. The aquarium wants to collaborate with the city and other partners to promote transformation of the Middle Branch waterfront, just as construction of its flagship building fueled the renewal of the Inner Harbor in the 1980s.

The building

A specific design has not been set. The aquarium has been working with Hord Coplan Macht of Baltimore to create a preliminary design that could give prospective donors an idea what it might be like. The design team, headed by Russ Robertson, proposed a center than consists of two parts: first, a greenhouse with natural light and solar heating and cooling, and second, a sod-roofed enclosure for natural insulation and filtration of storm water runoff. Inside the greenhouse would be marine animals that have exposure to ultraviolet light; beneath the earthen mound would be marine animals with temperature-sensitive needs.

The building would be an essentially private use - mostly off limits to the public but open for guided tours and other controlled events. The surrounding park would be for public use, open from dawn to dusk, with a fishing pier for the community. The landscape of restored wetlands, native plants, trees and marsh grasses would further help clean up storm water runoff and protect the site from erosion.

An innovative environmental technology, called "phytoremediation," may be used as a way to biologically eliminate low levels of pollutants in the soil.

"I view this site holistically as a series of contrasts, starting with the contrast between the developed urban waterfront of the Inner Harbor and the green, natural waterfront of the Middle Branch," Robertson said.

"Even if the public can't enter every part of the building, it will demonstrate bioretention, stormwater management and wetlands restoration. The site itself will be an exhibit of these and other activities."

Improving community

The preliminary design received awards this fall from the Baltimore chapter of the American Institute of Architects and the Maryland Society of the AIA. The aquarium itself was named the Client of the Year by the Baltimore chapter, for its commitment to conservation and community improvement.

As part of the design effort, the aquarium board and staff this fall enlisted national experts in "green design" to review the preliminary plans and recommend ways to make the building even more eco-friendly. The team was led by William Browning and Ben Shepherd of the Rocky Mountain Institute's Green Development Services, a leading consultant in the field of sustainable building design. Its past clients range from Wal-Mart, Monsanto and filmmaker George Lucas to the White House, the Pentagon and the 2000 Sydney Olympics.

Over a two-day period, the experts brainstormed with aquarium officials about ways to make the Middle Branch project one of the most environmentally sensitive structures in the country, and one of the first laboratory buildings to receive the top rating for Leadership in Environmental Engineering and Design (LEED) from the U.S. Green Building Council. Their recommendations will be used to draft the final building program and design guidelines.

The aquarium also is looking for ideas from the general public. It's holding a town meeting at 6:30 p.m. Wednesday to present plans for the project and get response from the community. The forum will be held at the Harbor Hospital Life Resources Center, 3001 S. Hanover St.

The construction timetable depends on the aquarium's ability to raise funds and obtain building permits. Officials hope to hire an architect and finish the design in time to begin construction in 2006 and open the building a year later. But even at this early stage, it's shaping up as an ideal "green" development for the Middle Branch.

The aquarium has always been a guardian of the environment and a champion of conservation. This project gives it the perfect opportunity to lead by example.