Thompson discusses the case of Olive 8 - "a swanky hotel/condo complex planned for downtown Seattle" - that was allowed to build beyond the 300-foot height limit allowed by zoning in exchange for the purchase of development rights out of King County's TDR bank. "When used this way," says Thompson, "TDRs encourage more of the kind of density essential for creating walkable cities with lower carbon footprints, while allowing cash-poor landowners to get some money out of their property without subdividing."
For Thompson, the attraction of a TDR program, versus other means of land protection such as conservation easements, is that it's market-based, meaning it doesn't rely on the generosity of individuals or non-profits, or increasingly imperiled public funds.
"'TDR creates this revolving funding source, where if we buy those [development] rights and then sell them, we recoup the initial outlay, and we can use that money to buy additional land,' explains Michael Murphy, manager of King County's TDR program. And, he says, there's the fact that 'it's voluntary and incentive-based, rather than a mandate so it's appealing to a broad spectrum of people.'"