Here's one of those good news, bad news stories.
    The other day I told you about how human-powered outdoor recreation generates some $730 billion for the U.S. economy each year. Well, today there's a report that says national park visits generate $10 billion annually for their local economies and support 236,000 jobs.
    That news comes straight from the National Park Service. According to the economic report, California benefits most from having national parks within its borders, with $1.2 billion in economic impact and nearly 27,000 related jobs generated during 2005.
    When it comes to individual parks, Great Smoky Mountains had the greatest economic impact on its surround communities, generating $652.5 in business last year and supporting 14238 jobs. Grand Canyon was second, with 416.4 million in business and nearly 10,000 jobs, while Yosemite was third, with $371 million in business and 8,948 jobs. You can see the entire list of parks and their economic impacts here.
    That's the good news. The bad news is that our national park system has many needs, ranging from attending to long-deferred maintenance to hiring more rangers for interpretation and law enforcement. Whether we as a nation -- and Congress specifically -- commit to addressing those needs will go a long way toward determining whether the national park system's economic impact continues to improve, or begins to falter.
    "If national parks are indeed an economic engine, that engine is way overdue for a tune-up," says Jeff Ruch, executive director of Public Employees for Environmental Responsibility. "To some extent, our national parks are becoming victims of their own success, drawing more development and traffic which risks turning the 'crown jewels' into smog bowls."
    Of course, another, equally important, question we should ponder is how much of an economic engine do we want our parks to be? After all, any boost in economic activity likely will carry a related toll on the parks, whether that be longer traffic jams, more pollution, more impact on the resources.
    As the saying goes, we need to be careful for what we ask.