When planners consider whether a proposed development warrants the destruction of a swath of seagrass or a stand of mangroves, they typically hear about how many jobs the project will create and how many dollars it will generate for the local economy. But the monetary value of the natural ecosystem itself is rarely discussed, usually because there’s no authoritative estimate.

“We’re trying to place functional rates and values on all that the different habitat types provide to humans.” — EPA research ecologist Marc Russell

In hopes of coming up with figures that will make sense to both sides of the development debate, the Environmental Protection Agency, as part of a five-year pilot study, is trying to quantify the economic value of Tampa Bay’s natural resources. The study presents a new way of looking at the existence value of natural habitats, which until now have only been given a price tag if resources are harvested and sold.

The EPA became interested in a study following Hurricane Katrina, when some argued that the loss of wetlands south of New Orleans contributed to flooding within the city. The study will look at storm surge issues here, as well as other potential benefits of the bay’s natural habitats — from wetlands filtering pollution to the role that seagrass beds play in nurturing the food chain and subsequently supporting the commercial fishing industry. “We’re trying to place functional rates and values on all that the different habitat types provide to humans,” says Marc Russell, an EPA research ecologist who is leading the Tampa Bay study.

Researchers don’t expect any answers until 2013. The key will be coming up with numbers that everyone can accept, says Suzanne Cooper, a principal planner with the Tampa Bay Regional Planning Council, which is aiding the study. “If the science community buys into it first and signs off on how we arrived at the numbers, then we can get local governments and state government to buy into the concept,” Cooper says. “Then we can talk in monetary terms about natural resources in ways that we never have before. The whole idea is to put it in a common language that can be put in a calculator.”