Harris Steinberg

is an architect and director of PennPraxis

Philadelphia is at a crossroads, and the road ahead runs along the Delaware River.

Cities around the world understand that public investment in parks, streets and boulevards should be guided by smart planning and land-use regulations. They understand the relationship between first-rate public design and quality of life.

What's more, from New York's 19th-century Central Park to Chicago's recent Millennium Park, we can see how targeted public investment in open space and infrastructure attracts private investment - more than paying for itself in the long run.

Indeed, Ed Uhlir, head of architecture, landscape architecture and design for Millennium Park, reports that the $350 million investment in public space (equal to one South Philly stadium) has yielded more than $4 billion in private investment in the surrounding area.

If Philadelphia is going to compete with New York, Chicago, Boston, Seattle and San Francisco for jobs, people, tax revenues and economic innovation, we must build public/private partnerships to invest in high-quality public spaces and infrastructure.

The Delaware riverfront is one of the key places where that needs to happen.

A civic vision for the central Delaware is starting to take shape - a thrilling road map of ideas both accessible and bold. These range from creating a series of neighborhood parks to investigating the sinking of Interstate 95 as it passes through Center City.

In early March, PennPraxis' public-design workshop generated excitement about the future of the riverfront. Convened to give form to the citywide civic vision for the central Delaware that Mayor Street has asked PennPraxis to help pull together, the workshop drew upon the talents of teams of international and local planners, landscape architects and designers alongside citizens, government officials and academics.

More than 500 people packed the Independence Seaport Museum on a sunny Saturday to see what the design teams produced as they worked from a set of publicly generated principles for the riverfront.

The teams inspired us with visions of what is possible along the nearly seven miles of Philadelphia's waterfront that stretch from Allegheny Avenue to Oregon Avenue and from the river to I-95.

The workshop surfaced important concepts:

Turning Delaware Avenue/Columbus Boulevard into an elegant boulevard with pedestrian paths, bike ways and new public transportation that would link a string of high-quality urban-development projects and open spaces.

Strengthening connections to the riverfront communities by building parks and open spaces along the water's edge every 2,000 feet.

Turning former 19th- and 20th-century industrial brownfields into model 21st-century live, work and play communities.

Naturalizing parts of the river's edge while uncovering long-buried streams to collect rainwater runoff.

Sinking parts of I-95, literally reconnecting the city with the Delaware while creating acres of new real estate. (You can watch the workshop presentations at www.planphilly.com.)

The design and planning experts urged Philadelphians to look beyond the present conditions along the river's edge, which include scores of haphazardly planned new construction projects (including two 5,000-slot casinos) and traffic jams caused by unchecked big-box development, along with largely inaccessible public spaces across the aching chasm of I-95.

The steps they recommended ranged from the swiftly doable (turning the city-owned former incinerator site at the foot of Spring Garden Street into a public park) to the generational (putting I-95 below ground).

The concepts are now being vetted and refined in collaboration with the Philadelphia City Planning Commission and the Pennsylvania Department of Transportation.

We are working closely with a 46-member advisory group that includes politicians, government officials, civic-group leaders and the public. The group meets the first Monday of each month on the 18th floor of 1515 Arch St. at 8 a.m; the sessions are open to the public.

You can keep tabs on the project and find out about future public forums by checking out www.planphilly.com.

It's important to note that the design ideas are based on a set of civic-design principles created by more than 1,700 Philadelphians who attended forums last fall and winter that were led by PennPraxis and the Penn Project on Civic Engagement.

The civic principles are:

Reconnect the city with the river by extending the small-scale Philadelphia street grid to the large parcels along the water's edge.

Make sure the river is taken seriously as both a working river and a significant natural resource.

Ensure that all new development includes ecologically sound planning, transportation and design principles.

Guarantee that the central Delaware offers a healthy balance of residential and commercial uses that support a vibrant urban community.

Most important, the principles admonish Philadelphia to take the long view and protect the public good by quelling the crush of pell-mell development that threatens to cut off the river behind a wall of private development.

Taking the long view is also critical to creating a sound, inspiring civic vision for the central Delaware.

If we want to play with the big boys - New York, San Francisco and Chicago - we need to invest in our future the way that they do.

It's our time, Philadelphia. Let's go down this road together.