Wednesday, November 20, 2013

Seeking high ground: Rising sea levels may affect future development

Published in the Portland Phoenix; sidebar to a larger feature by Deirdre Fulton on development in the Bayside area of Portland

As developers, residents, and city officials plan the future of Bayside, they’ll have to wrestle with some very difficult questions. A sense of the flavor of those discussions was on display at the Portland Society for Architecture “Waterfront Visions 2050” community workshop, held a couple weeks back at SPACE Gallery.
The first several minutes were spent defining common terms, such as what the phrase “100-year storm” means. (Confusing but true: It’s not a storm that happens every 100 years, but rather a storm that has a one percent chance of occurring in any given year. They can happen in back-to-back years, or with far more than 100 years between them.)
The basics are hard enough in a room of 50 people paying close attention; when dealing with public policy, it’s important to ensure the wider public is accurately informed, which also means ensuring journalists covering the process understand variations in terminology.
For example, maps and scientific disciplines discuss sea level in different terms, such as  measuring distance above the normal high-tide line or calculating a mean sea level that equals out tides and waves. So when one person talks about sea level rising four or five feet, another might need to translate that to as many as nine or 10 feet, depending on how each is measuring the changing water level.
But even after that is sorted out, it’s not enough to think about just the parcel of land being developed. In some cases, high ground may seem safe enough to build on, but a look at the surrounding land will reveal that new shopping center will one day be on an island with no road access.
And when multiple interconnected and interrelated properties are under consideration, owners’ differences can cause tension. One small group at the PSA event seemed focused on what to do about the piers on Commercial Street — raise them, protect them, convert them to floating platforms? — while another group simply moved their projected waterfront back far enough to surrender some property to the ocean. But that would mean consigning the piers to the deep, something the other group didn’t even discuss.
Of course, expense is a problem. Developers have to determine how much they’re willing to invest in a property — which, in places near sea level, means calculating how much it costs to raise the street levels, or how much profit can be squeezed from a development in the few remaining years or decades before it’s underwater . Public officials have to figure out what’s cost-effective to use taxpayer dollars for. (See “How Wet Will Portland Get?” by Jeff Inglis, October 4.)
Also making discussions challenging is the fact that some waterfront land is contaminated (or just plain made of trash used to fill in wetlands 150 years ago both on Commercial Street and the area around Back Cove) — if that land is submerged, the contaminants may leak out into the global seas.
And beyond that is a whole host of state and federal regulations about what can be built, with what restrictions, near the shoreline.
Even if an individual project seems straightforward (and they rarely do!), each new proposal will stir up these and other important questions, as we determine how to adapt to our changing planet.